Search Results

Search found 66085 results on 2644 pages for 'response time'.

Page 95/2644 | < Previous Page | 91 92 93 94 95 96 97 98 99 100 101 102  | Next Page >

  • Windows 8: 100% disk active time, no actual data transferred

    - by fingerbangpalateclick
    Occasionally, like several times an hour, my hard drive will appear to lock up: Task Manager will show 100% active time with read and write speeds of 0. I can still switch between open windows, but anything that requires a disk access will stall for around a minute until the hard disk starts working properly again. It happens at apparently random intervals, and only happens in Windows 8. Not 7, nor Linux. It is probably not a problem with the disk itself: This is a relatively new hard drive, and S.M.A.R.T. is showing no errors. Only happens in Windows 8: not any other OS that has used the same partition, or different partitions. So, what is going on? How can I fix this? Note: this is a different problem then this one: Extremely high disk activity without any real usage My task manager would look similar, but Average Response Time, Read Speed, and Write Speed would all be 0.

    Read the article

  • An Introduction to ASP.NET Web API

    - by Rick Strahl
    Microsoft recently released ASP.NET MVC 4.0 and .NET 4.5 and along with it, the brand spanking new ASP.NET Web API. Web API is an exciting new addition to the ASP.NET stack that provides a new, well-designed HTTP framework for creating REST and AJAX APIs (API is Microsoft’s new jargon for a service, in case you’re wondering). Although Web API ships and installs with ASP.NET MVC 4, you can use Web API functionality in any ASP.NET project, including WebForms, WebPages and MVC or just a Web API by itself. And you can also self-host Web API in your own applications from Console, Desktop or Service applications. If you're interested in a high level overview on what ASP.NET Web API is and how it fits into the ASP.NET stack you can check out my previous post: Where does ASP.NET Web API fit? In the following article, I'll focus on a practical, by example introduction to ASP.NET Web API. All the code discussed in this article is available in GitHub: https://github.com/RickStrahl/AspNetWebApiArticle [republished from my Code Magazine Article and updated for RTM release of ASP.NET Web API] Getting Started To start I’ll create a new empty ASP.NET application to demonstrate that Web API can work with any kind of ASP.NET project. Although you can create a new project based on the ASP.NET MVC/Web API template to quickly get up and running, I’ll take you through the manual setup process, because one common use case is to add Web API functionality to an existing ASP.NET application. This process describes the steps needed to hook up Web API to any ASP.NET 4.0 application. Start by creating an ASP.NET Empty Project. Then create a new folder in the project called Controllers. Add a Web API Controller Class Once you have any kind of ASP.NET project open, you can add a Web API Controller class to it. Web API Controllers are very similar to MVC Controller classes, but they work in any kind of project. Add a new item to this folder by using the Add New Item option in Visual Studio and choose Web API Controller Class, as shown in Figure 1. Figure 1: This is how you create a new Controller Class in Visual Studio   Make sure that the name of the controller class includes Controller at the end of it, which is required in order for Web API routing to find it. Here, the name for the class is AlbumApiController. For this example, I’ll use a Music Album model to demonstrate basic behavior of Web API. The model consists of albums and related songs where an album has properties like Name, Artist and YearReleased and a list of songs with a SongName and SongLength as well as an AlbumId that links it to the album. You can find the code for the model (and the rest of these samples) on Github. To add the file manually, create a new folder called Model, and add a new class Album.cs and copy the code into it. There’s a static AlbumData class with a static CreateSampleAlbumData() method that creates a short list of albums on a static .Current that I’ll use for the examples. Before we look at what goes into the controller class though, let’s hook up routing so we can access this new controller. Hooking up Routing in Global.asax To start, I need to perform the one required configuration task in order for Web API to work: I need to configure routing to the controller. Like MVC, Web API uses routing to provide clean, extension-less URLs to controller methods. Using an extension method to ASP.NET’s static RouteTable class, you can use the MapHttpRoute() (in the System.Web.Http namespace) method to hook-up the routing during Application_Start in global.asax.cs shown in Listing 1.using System; using System.Web.Routing; using System.Web.Http; namespace AspNetWebApi { public class Global : System.Web.HttpApplication { protected void Application_Start(object sender, EventArgs e) { RouteTable.Routes.MapHttpRoute( name: "AlbumVerbs", routeTemplate: "albums/{title}", defaults: new { symbol = RouteParameter.Optional, controller="AlbumApi" } ); } } } This route configures Web API to direct URLs that start with an albums folder to the AlbumApiController class. Routing in ASP.NET is used to create extensionless URLs and allows you to map segments of the URL to specific Route Value parameters. A route parameter, with a name inside curly brackets like {name}, is mapped to parameters on the controller methods. Route parameters can be optional, and there are two special route parameters – controller and action – that determine the controller to call and the method to activate respectively. HTTP Verb Routing Routing in Web API can route requests by HTTP Verb in addition to standard {controller},{action} routing. For the first examples, I use HTTP Verb routing, as shown Listing 1. Notice that the route I’ve defined does not include an {action} route value or action value in the defaults. Rather, Web API can use the HTTP Verb in this route to determine the method to call the controller, and a GET request maps to any method that starts with Get. So methods called Get() or GetAlbums() are matched by a GET request and a POST request maps to a Post() or PostAlbum(). Web API matches a method by name and parameter signature to match a route, query string or POST values. In lieu of the method name, the [HttpGet,HttpPost,HttpPut,HttpDelete, etc] attributes can also be used to designate the accepted verbs explicitly if you don’t want to follow the verb naming conventions. Although HTTP Verb routing is a good practice for REST style resource APIs, it’s not required and you can still use more traditional routes with an explicit {action} route parameter. When {action} is supplied, the HTTP verb routing is ignored. I’ll talk more about alternate routes later. When you’re finished with initial creation of files, your project should look like Figure 2.   Figure 2: The initial project has the new API Controller Album model   Creating a small Album Model Now it’s time to create some controller methods to serve data. For these examples, I’ll use a very simple Album and Songs model to play with, as shown in Listing 2. public class Song { public string AlbumId { get; set; } [Required, StringLength(80)] public string SongName { get; set; } [StringLength(5)] public string SongLength { get; set; } } public class Album { public string Id { get; set; } [Required, StringLength(80)] public string AlbumName { get; set; } [StringLength(80)] public string Artist { get; set; } public int YearReleased { get; set; } public DateTime Entered { get; set; } [StringLength(150)] public string AlbumImageUrl { get; set; } [StringLength(200)] public string AmazonUrl { get; set; } public virtual List<Song> Songs { get; set; } public Album() { Songs = new List<Song>(); Entered = DateTime.Now; // Poor man's unique Id off GUID hash Id = Guid.NewGuid().GetHashCode().ToString("x"); } public void AddSong(string songName, string songLength = null) { this.Songs.Add(new Song() { AlbumId = this.Id, SongName = songName, SongLength = songLength }); } } Once the model has been created, I also added an AlbumData class that generates some static data in memory that is loaded onto a static .Current member. The signature of this class looks like this and that's what I'll access to retrieve the base data:public static class AlbumData { // sample data - static list public static List<Album> Current = CreateSampleAlbumData(); /// <summary> /// Create some sample data /// </summary> /// <returns></returns> public static List<Album> CreateSampleAlbumData() { … }} You can check out the full code for the data generation online. Creating an AlbumApiController Web API shares many concepts of ASP.NET MVC, and the implementation of your API logic is done by implementing a subclass of the System.Web.Http.ApiController class. Each public method in the implemented controller is a potential endpoint for the HTTP API, as long as a matching route can be found to invoke it. The class name you create should end in Controller, which is how Web API matches the controller route value to figure out which class to invoke. Inside the controller you can implement methods that take standard .NET input parameters and return .NET values as results. Web API’s binding tries to match POST data, route values, form values or query string values to your parameters. Because the controller is configured for HTTP Verb based routing (no {action} parameter in the route), any methods that start with Getxxxx() are called by an HTTP GET operation. You can have multiple methods that match each HTTP Verb as long as the parameter signatures are different and can be matched by Web API. In Listing 3, I create an AlbumApiController with two methods to retrieve a list of albums and a single album by its title .public class AlbumApiController : ApiController { public IEnumerable<Album> GetAlbums() { var albums = AlbumData.Current.OrderBy(alb => alb.Artist); return albums; } public Album GetAlbum(string title) { var album = AlbumData.Current .SingleOrDefault(alb => alb.AlbumName.Contains(title)); return album; }} To access the first two requests, you can use the following URLs in your browser: http://localhost/aspnetWebApi/albumshttp://localhost/aspnetWebApi/albums/Dirty%20Deeds Note that you’re not specifying the actions of GetAlbum or GetAlbums in these URLs. Instead Web API’s routing uses HTTP GET verb to route to these methods that start with Getxxx() with the first mapping to the parameterless GetAlbums() method and the latter to the GetAlbum(title) method that receives the title parameter mapped as optional in the route. Content Negotiation When you access any of the URLs above from a browser, you get either an XML or JSON result returned back. The album list result for Chrome 17 and Internet Explorer 9 is shown Figure 3. Figure 3: Web API responses can vary depending on the browser used, demonstrating Content Negotiation in action as these two browsers send different HTTP Accept headers.   Notice that the results are not the same: Chrome returns an XML response and IE9 returns a JSON response. Whoa, what’s going on here? Shouldn’t we see the same result in both browsers? Actually, no. Web API determines what type of content to return based on Accept headers. HTTP clients, like browsers, use Accept headers to specify what kind of content they’d like to see returned. Browsers generally ask for HTML first, followed by a few additional content types. Chrome (and most other major browsers) ask for: Accept: text/html, application/xhtml+xml,application/xml; q=0.9,*/*;q=0.8 IE9 asks for: Accept: text/html, application/xhtml+xml, */* Note that Chrome’s Accept header includes application/xml, which Web API finds in its list of supported media types and returns an XML response. IE9 does not include an Accept header type that works on Web API by default, and so it returns the default format, which is JSON. This is an important and very useful feature that was missing from any previous Microsoft REST tools: Web API automatically switches output formats based on HTTP Accept headers. Nowhere in the server code above do you have to explicitly specify the output format. Rather, Web API determines what format the client is requesting based on the Accept headers and automatically returns the result based on the available formatters. This means that a single method can handle both XML and JSON results.. Using this simple approach makes it very easy to create a single controller method that can return JSON, XML, ATOM or even OData feeds by providing the appropriate Accept header from the client. By default you don’t have to worry about the output format in your code. Note that you can still specify an explicit output format if you choose, either globally by overriding the installed formatters, or individually by returning a lower level HttpResponseMessage instance and setting the formatter explicitly. More on that in a minute. Along the same lines, any content sent to the server via POST/PUT is parsed by Web API based on the HTTP Content-type of the data sent. The same formats allowed for output are also allowed on input. Again, you don’t have to do anything in your code – Web API automatically performs the deserialization from the content. Accessing Web API JSON Data with jQuery A very common scenario for Web API endpoints is to retrieve data for AJAX calls from the Web browser. Because JSON is the default format for Web API, it’s easy to access data from the server using jQuery and its getJSON() method. This example receives the albums array from GetAlbums() and databinds it into the page using knockout.js.$.getJSON("albums/", function (albums) { // make knockout template visible $(".album").show(); // create view object and attach array var view = { albums: albums }; ko.applyBindings(view); }); Figure 4 shows this and the next example’s HTML output. You can check out the complete HTML and script code at http://goo.gl/Ix33C (.html) and http://goo.gl/tETlg (.js). Figu Figure 4: The Album Display sample uses JSON data loaded from Web API.   The result from the getJSON() call is a JavaScript object of the server result, which comes back as a JavaScript array. In the code, I use knockout.js to bind this array into the UI, which as you can see, requires very little code, instead using knockout’s data-bind attributes to bind server data to the UI. Of course, this is just one way to use the data – it’s entirely up to you to decide what to do with the data in your client code. Along the same lines, I can retrieve a single album to display when the user clicks on an album. The response returns the album information and a child array with all the songs. The code to do this is very similar to the last example where we pulled the albums array:$(".albumlink").live("click", function () { var id = $(this).data("id"); // title $.getJSON("albums/" + id, function (album) { ko.applyBindings(album, $("#divAlbumDialog")[0]); $("#divAlbumDialog").show(); }); }); Here the URL looks like this: /albums/Dirty%20Deeds, where the title is the ID captured from the clicked element’s data ID attribute. Explicitly Overriding Output Format When Web API automatically converts output using content negotiation, it does so by matching Accept header media types to the GlobalConfiguration.Configuration.Formatters and the SupportedMediaTypes of each individual formatter. You can add and remove formatters to globally affect what formats are available and it’s easy to create and plug in custom formatters.The example project includes a JSONP formatter that can be plugged in to provide JSONP support for requests that have a callback= querystring parameter. Adding, removing or replacing formatters is a global option you can use to manipulate content. It’s beyond the scope of this introduction to show how it works, but you can review the sample code or check out my blog entry on the subject (http://goo.gl/UAzaR). If automatic processing is not desirable in a particular Controller method, you can override the response output explicitly by returning an HttpResponseMessage instance. HttpResponseMessage is similar to ActionResult in ASP.NET MVC in that it’s a common way to return an abstract result message that contains content. HttpResponseMessage s parsed by the Web API framework using standard interfaces to retrieve the response data, status code, headers and so on[MS2] . Web API turns every response – including those Controller methods that return static results – into HttpResponseMessage instances. Explicitly returning an HttpResponseMessage instance gives you full control over the output and lets you mostly bypass WebAPI’s post-processing of the HTTP response on your behalf. HttpResponseMessage allows you to customize the response in great detail. Web API’s attention to detail in the HTTP spec really shows; many HTTP options are exposed as properties and enumerations with detailed IntelliSense comments. Even if you’re new to building REST-based interfaces, the API guides you in the right direction for returning valid responses and response codes. For example, assume that I always want to return JSON from the GetAlbums() controller method and ignore the default media type content negotiation. To do this, I can adjust the output format and headers as shown in Listing 4.public HttpResponseMessage GetAlbums() { var albums = AlbumData.Current.OrderBy(alb => alb.Artist); // Create a new HttpResponse with Json Formatter explicitly var resp = new HttpResponseMessage(HttpStatusCode.OK); resp.Content = new ObjectContent<IEnumerable<Album>>( albums, new JsonMediaTypeFormatter()); // Get Default Formatter based on Content Negotiation //var resp = Request.CreateResponse<IEnumerable<Album>>(HttpStatusCode.OK, albums); resp.Headers.ConnectionClose = true; resp.Headers.CacheControl = new CacheControlHeaderValue(); resp.Headers.CacheControl.Public = true; return resp; } This example returns the same IEnumerable<Album> value, but it wraps the response into an HttpResponseMessage so you can control the entire HTTP message result including the headers, formatter and status code. In Listing 4, I explicitly specify the formatter using the JsonMediaTypeFormatter to always force the content to JSON.  If you prefer to use the default content negotiation with HttpResponseMessage results, you can create the Response instance using the Request.CreateResponse method:var resp = Request.CreateResponse<IEnumerable<Album>>(HttpStatusCode.OK, albums); This provides you an HttpResponse object that's pre-configured with the default formatter based on Content Negotiation. Once you have an HttpResponse object you can easily control most HTTP aspects on this object. What's sweet here is that there are many more detailed properties on HttpResponse than the core ASP.NET Response object, with most options being explicitly configurable with enumerations that make it easy to pick the right headers and response codes from a list of valid codes. It makes HTTP features available much more discoverable even for non-hardcore REST/HTTP geeks. Non-Serialized Results The output returned doesn’t have to be a serialized value but can also be raw data, like strings, binary data or streams. You can use the HttpResponseMessage.Content object to set a number of common Content classes. Listing 5 shows how to return a binary image using the ByteArrayContent class from a Controller method. [HttpGet] public HttpResponseMessage AlbumArt(string title) { var album = AlbumData.Current.FirstOrDefault(abl => abl.AlbumName.StartsWith(title)); if (album == null) { var resp = Request.CreateResponse<ApiMessageError>( HttpStatusCode.NotFound, new ApiMessageError("Album not found")); return resp; } // kinda silly - we would normally serve this directly // but hey - it's a demo. var http = new WebClient(); var imageData = http.DownloadData(album.AlbumImageUrl); // create response and return var result = new HttpResponseMessage(HttpStatusCode.OK); result.Content = new ByteArrayContent(imageData); result.Content.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg"); return result; } The image retrieval from Amazon is contrived, but it shows how to return binary data using ByteArrayContent. It also demonstrates that you can easily return multiple types of content from a single controller method, which is actually quite common. If an error occurs - such as a resource can’t be found or a validation error – you can return an error response to the client that’s very specific to the error. In GetAlbumArt(), if the album can’t be found, we want to return a 404 Not Found status (and realistically no error, as it’s an image). Note that if you are not using HTTP Verb-based routing or not accessing a method that starts with Get/Post etc., you have to specify one or more HTTP Verb attributes on the method explicitly. Here, I used the [HttpGet] attribute to serve the image. Another option to handle the error could be to return a fixed placeholder image if no album could be matched or the album doesn’t have an image. When returning an error code, you can also return a strongly typed response to the client. For example, you can set the 404 status code and also return a custom error object (ApiMessageError is a class I defined) like this:return Request.CreateResponse<ApiMessageError>( HttpStatusCode.NotFound, new ApiMessageError("Album not found") );   If the album can be found, the image will be returned. The image is downloaded into a byte[] array, and then assigned to the result’s Content property. I created a new ByteArrayContent instance and assigned the image’s bytes and the content type so that it displays properly in the browser. There are other content classes available: StringContent, StreamContent, ByteArrayContent, MultipartContent, and ObjectContent are at your disposal to return just about any kind of content. You can create your own Content classes if you frequently return custom types and handle the default formatter assignments that should be used to send the data out . Although HttpResponseMessage results require more code than returning a plain .NET value from a method, it allows much more control over the actual HTTP processing than automatic processing. It also makes it much easier to test your controller methods as you get a response object that you can check for specific status codes and output messages rather than just a result value. Routing Again Ok, let’s get back to the image example. Using the original routing we have setup using HTTP Verb routing there's no good way to serve the image. In order to return my album art image I’d like to use a URL like this: http://localhost/aspnetWebApi/albums/Dirty%20Deeds/image In order to create a URL like this, I have to create a new Controller because my earlier routes pointed to the AlbumApiController using HTTP Verb routing. HTTP Verb based routing is great for representing a single set of resources such as albums. You can map operations like add, delete, update and read easily using HTTP Verbs. But you cannot mix action based routing into a an HTTP Verb routing controller - you can only map HTTP Verbs and each method has to be unique based on parameter signature. You can't have multiple GET operations to methods with the same signature. So GetImage(string id) and GetAlbum(string title) are in conflict in an HTTP GET routing scenario. In fact, I was unable to make the above Image URL work with any combination of HTTP Verb plus Custom routing using the single Albums controller. There are number of ways around this, but all involve additional controllers.  Personally, I think it’s easier to use explicit Action routing and then add custom routes if you need to simplify your URLs further. So in order to accommodate some of the other examples, I created another controller – AlbumRpcApiController – to handle all requests that are explicitly routed via actions (/albums/rpc/AlbumArt) or are custom routed with explicit routes defined in the HttpConfiguration. I added the AlbumArt() method to this new AlbumRpcApiController class. For the image URL to work with the new AlbumRpcApiController, you need a custom route placed before the default route from Listing 1.RouteTable.Routes.MapHttpRoute( name: "AlbumRpcApiAction", routeTemplate: "albums/rpc/{action}/{title}", defaults: new { title = RouteParameter.Optional, controller = "AlbumRpcApi", action = "GetAblums" } ); Now I can use either of the following URLs to access the image: Custom route: (/albums/rpc/{title}/image)http://localhost/aspnetWebApi/albums/PowerAge/image Action route: (/albums/rpc/action/{title})http://localhost/aspnetWebAPI/albums/rpc/albumart/PowerAge Sending Data to the Server To send data to the server and add a new album, you can use an HTTP POST operation. Since I’m using HTTP Verb-based routing in the original AlbumApiController, I can implement a method called PostAlbum()to accept a new album from the client. Listing 6 shows the Web API code to add a new album.public HttpResponseMessage PostAlbum(Album album) { if (!this.ModelState.IsValid) { // my custom error class var error = new ApiMessageError() { message = "Model is invalid" }; // add errors into our client error model for client foreach (var prop in ModelState.Values) { var modelError = prop.Errors.FirstOrDefault(); if (!string.IsNullOrEmpty(modelError.ErrorMessage)) error.errors.Add(modelError.ErrorMessage); else error.errors.Add(modelError.Exception.Message); } return Request.CreateResponse<ApiMessageError>(HttpStatusCode.Conflict, error); } // update song id which isn't provided foreach (var song in album.Songs) song.AlbumId = album.Id; // see if album exists already var matchedAlbum = AlbumData.Current .SingleOrDefault(alb => alb.Id == album.Id || alb.AlbumName == album.AlbumName); if (matchedAlbum == null) AlbumData.Current.Add(album); else matchedAlbum = album; // return a string to show that the value got here var resp = Request.CreateResponse(HttpStatusCode.OK, string.Empty); resp.Content = new StringContent(album.AlbumName + " " + album.Entered.ToString(), Encoding.UTF8, "text/plain"); return resp; } The PostAlbum() method receives an album parameter, which is automatically deserialized from the POST buffer the client sent. The data passed from the client can be either XML or JSON. Web API automatically figures out what format it needs to deserialize based on the content type and binds the content to the album object. Web API uses model binding to bind the request content to the parameter(s) of controller methods. Like MVC you can check the model by looking at ModelState.IsValid. If it’s not valid, you can run through the ModelState.Values collection and check each binding for errors. Here I collect the error messages into a string array that gets passed back to the client via the result ApiErrorMessage object. When a binding error occurs, you’ll want to return an HTTP error response and it’s best to do that with an HttpResponseMessage result. In Listing 6, I used a custom error class that holds a message and an array of detailed error messages for each binding error. I used this object as the content to return to the client along with my Conflict HTTP Status Code response. If binding succeeds, the example returns a string with the name and date entered to demonstrate that you captured the data. Normally, a method like this should return a Boolean or no response at all (HttpStatusCode.NoConent). The sample uses a simple static list to hold albums, so once you’ve added the album using the Post operation, you can hit the /albums/ URL to see that the new album was added. The client jQuery code to call the POST operation from the client with jQuery is shown in Listing 7. var id = new Date().getTime().toString(); var album = { "Id": id, "AlbumName": "Power Age", "Artist": "AC/DC", "YearReleased": 1977, "Entered": "2002-03-11T18:24:43.5580794-10:00", "AlbumImageUrl": http://ecx.images-amazon.com/images/…, "AmazonUrl": http://www.amazon.com/…, "Songs": [ { "SongName": "Rock 'n Roll Damnation", "SongLength": 3.12}, { "SongName": "Downpayment Blues", "SongLength": 4.22 }, { "SongName": "Riff Raff", "SongLength": 2.42 } ] } $.ajax( { url: "albums/", type: "POST", contentType: "application/json", data: JSON.stringify(album), processData: false, beforeSend: function (xhr) { // not required since JSON is default output xhr.setRequestHeader("Accept", "application/json"); }, success: function (result) { // reload list of albums page.loadAlbums(); }, error: function (xhr, status, p3, p4) { var err = "Error"; if (xhr.responseText && xhr.responseText[0] == "{") err = JSON.parse(xhr.responseText).message; alert(err); } }); The code in Listing 7 creates an album object in JavaScript to match the structure of the .NET Album class. This object is passed to the $.ajax() function to send to the server as POST. The data is turned into JSON and the content type set to application/json so that the server knows what to convert when deserializing in the Album instance. The jQuery code hooks up success and failure events. Success returns the result data, which is a string that’s echoed back with an alert box. If an error occurs, jQuery returns the XHR instance and status code. You can check the XHR to see if a JSON object is embedded and if it is, you can extract it by de-serializing it and accessing the .message property. REST standards suggest that updates to existing resources should use PUT operations. REST standards aside, I’m not a big fan of separating out inserts and updates so I tend to have a single method that handles both. But if you want to follow REST suggestions, you can create a PUT method that handles updates by forwarding the PUT operation to the POST method:public HttpResponseMessage PutAlbum(Album album) { return PostAlbum(album); } To make the corresponding $.ajax() call, all you have to change from Listing 7 is the type: from POST to PUT. Model Binding with UrlEncoded POST Variables In the example in Listing 7 I used JSON objects to post a serialized object to a server method that accepted an strongly typed object with the same structure, which is a common way to send data to the server. However, Web API supports a number of different ways that data can be received by server methods. For example, another common way is to use plain UrlEncoded POST  values to send to the server. Web API supports Model Binding that works similar (but not the same) as MVC's model binding where POST variables are mapped to properties of object parameters of the target method. This is actually quite common for AJAX calls that want to avoid serialization and the potential requirement of a JSON parser on older browsers. For example, using jQUery you might use the $.post() method to send a new album to the server (albeit one without songs) using code like the following:$.post("albums/",{AlbumName: "Dirty Deeds", YearReleased: 1976 … },albumPostCallback); Although the code looks very similar to the client code we used before passing JSON, here the data passed is URL encoded values (AlbumName=Dirty+Deeds&YearReleased=1976 etc.). Web API then takes this POST data and maps each of the POST values to the properties of the Album object in the method's parameter. Although the client code is different the server can both handle the JSON object, or the UrlEncoded POST values. Dynamic Access to POST Data There are also a few options available to dynamically access POST data, if you know what type of data you're dealing with. If you have POST UrlEncoded values, you can dynamically using a FormsDataCollection:[HttpPost] public string PostAlbum(FormDataCollection form) { return string.Format("{0} - released {1}", form.Get("AlbumName"),form.Get("RearReleased")); } The FormDataCollection is a very simple object, that essentially provides the same functionality as Request.Form[] in ASP.NET. Request.Form[] still works if you're running hosted in an ASP.NET application. However as a general rule, while ASP.NET's functionality is always available when running Web API hosted inside of an  ASP.NET application, using the built in classes specific to Web API makes it possible to run Web API applications in a self hosted environment outside of ASP.NET. If your client is sending JSON to your server, and you don't want to map the JSON to a strongly typed object because you only want to retrieve a few simple values, you can also accept a JObject parameter in your API methods:[HttpPost] public string PostAlbum(JObject jsonData) { dynamic json = jsonData; JObject jalbum = json.Album; JObject juser = json.User; string token = json.UserToken; var album = jalbum.ToObject<Album>(); var user = juser.ToObject<User>(); return String.Format("{0} {1} {2}", album.AlbumName, user.Name, token); } There quite a few options available to you to receive data with Web API, which gives you more choices for the right tool for the job. Unfortunately one shortcoming of Web API is that POST data is always mapped to a single parameter. This means you can't pass multiple POST parameters to methods that receive POST data. It's possible to accept multiple parameters, but only one can map to the POST content - the others have to come from the query string or route values. I have a couple of Blog POSTs that explain what works and what doesn't here: Passing multiple POST parameters to Web API Controller Methods Mapping UrlEncoded POST Values in ASP.NET Web API   Handling Delete Operations Finally, to round out the server API code of the album example we've been discussin, here’s the DELETE verb controller method that allows removal of an album by its title:public HttpResponseMessage DeleteAlbum(string title) { var matchedAlbum = AlbumData.Current.Where(alb => alb.AlbumName == title) .SingleOrDefault(); if (matchedAlbum == null) return new HttpResponseMessage(HttpStatusCode.NotFound); AlbumData.Current.Remove(matchedAlbum); return new HttpResponseMessage(HttpStatusCode.NoContent); } To call this action method using jQuery, you can use:$(".removeimage").live("click", function () { var $el = $(this).parent(".album"); var txt = $el.find("a").text(); $.ajax({ url: "albums/" + encodeURIComponent(txt), type: "Delete", success: function (result) { $el.fadeOut().remove(); }, error: jqError }); }   Note the use of the DELETE verb in the $.ajax() call, which routes to DeleteAlbum on the server. DELETE is a non-content operation, so you supply a resource ID (the title) via route value or the querystring. Routing Conflicts In all requests with the exception of the AlbumArt image example shown so far, I used HTTP Verb routing that I set up in Listing 1. HTTP Verb Routing is a recommendation that is in line with typical REST access to HTTP resources. However, it takes quite a bit of effort to create REST-compliant API implementations based only on HTTP Verb routing only. You saw one example that didn’t really fit – the return of an image where I created a custom route albums/{title}/image that required creation of a second controller and a custom route to work. HTTP Verb routing to a controller does not mix with custom or action routing to the same controller because of the limited mapping of HTTP verbs imposed by HTTP Verb routing. To understand some of the problems with verb routing, let’s look at another example. Let’s say you create a GetSortableAlbums() method like this and add it to the original AlbumApiController accessed via HTTP Verb routing:[HttpGet] public IQueryable<Album> SortableAlbums() { var albums = AlbumData.Current; // generally should be done only on actual queryable results (EF etc.) // Done here because we're running with a static list but otherwise might be slow return albums.AsQueryable(); } If you compile this code and try to now access the /albums/ link, you get an error: Multiple Actions were found that match the request. HTTP Verb routing only allows access to one GET operation per parameter/route value match. If more than one method exists with the same parameter signature, it doesn’t work. As I mentioned earlier for the image display, the only solution to get this method to work is to throw it into another controller. Because I already set up the AlbumRpcApiController I can add the method there. First, I should rename the method to SortableAlbums() so I’m not using a Get prefix for the method. This also makes the action parameter look cleaner in the URL - it looks less like a method and more like a noun. I can then create a new route that handles direct-action mapping:RouteTable.Routes.MapHttpRoute( name: "AlbumRpcApiAction", routeTemplate: "albums/rpc/{action}/{title}", defaults: new { title = RouteParameter.Optional, controller = "AlbumRpcApi", action = "GetAblums" } ); As I am explicitly adding a route segment – rpc – into the route template, I can now reference explicit methods in the Web API controller using URLs like this: http://localhost/AspNetWebApi/rpc/SortableAlbums Error Handling I’ve already done some minimal error handling in the examples. For example in Listing 6, I detected some known-error scenarios like model validation failing or a resource not being found and returning an appropriate HttpResponseMessage result. But what happens if your code just blows up or causes an exception? If you have a controller method, like this:[HttpGet] public void ThrowException() { throw new UnauthorizedAccessException("Unauthorized Access Sucka"); } You can call it with this: http://localhost/AspNetWebApi/albums/rpc/ThrowException The default exception handling displays a 500-status response with the serialized exception on the local computer only. When you connect from a remote computer, Web API throws back a 500  HTTP Error with no data returned (IIS then adds its HTML error page). The behavior is configurable in the GlobalConfiguration:GlobalConfiguration .Configuration .IncludeErrorDetailPolicy = IncludeErrorDetailPolicy.Never; If you want more control over your error responses sent from code, you can throw explicit error responses yourself using HttpResponseException. When you throw an HttpResponseException the response parameter is used to generate the output for the Controller action. [HttpGet] public void ThrowError() { var resp = Request.CreateResponse<ApiMessageError>( HttpStatusCode.BadRequest, new ApiMessageError("Your code stinks!")); throw new HttpResponseException(resp); } Throwing an HttpResponseException stops the processing of the controller method and immediately returns the response you passed to the exception. Unlike other Exceptions fired inside of WebAPI, HttpResponseException bypasses the Exception Filters installed and instead just outputs the response you provide. In this case, the serialized ApiMessageError result string is returned in the default serialization format – XML or JSON. You can pass any content to HttpResponseMessage, which includes creating your own exception objects and consistently returning error messages to the client. Here’s a small helper method on the controller that you might use to send exception info back to the client consistently:private void ThrowSafeException(string message, HttpStatusCode statusCode = HttpStatusCode.BadRequest) { var errResponse = Request.CreateResponse<ApiMessageError>(statusCode, new ApiMessageError() { message = message }); throw new HttpResponseException(errResponse); } You can then use it to output any captured errors from code:[HttpGet] public void ThrowErrorSafe() { try { List<string> list = null; list.Add("Rick"); } catch (Exception ex) { ThrowSafeException(ex.Message); } }   Exception Filters Another more global solution is to create an Exception Filter. Filters in Web API provide the ability to pre- and post-process controller method operations. An exception filter looks at all exceptions fired and then optionally creates an HttpResponseMessage result. Listing 8 shows an example of a basic Exception filter implementation.public class UnhandledExceptionFilter : ExceptionFilterAttribute { public override void OnException(HttpActionExecutedContext context) { HttpStatusCode status = HttpStatusCode.InternalServerError; var exType = context.Exception.GetType(); if (exType == typeof(UnauthorizedAccessException)) status = HttpStatusCode.Unauthorized; else if (exType == typeof(ArgumentException)) status = HttpStatusCode.NotFound; var apiError = new ApiMessageError() { message = context.Exception.Message }; // create a new response and attach our ApiError object // which now gets returned on ANY exception result var errorResponse = context.Request.CreateResponse<ApiMessageError>(status, apiError); context.Response = errorResponse; base.OnException(context); } } Exception Filter Attributes can be assigned to an ApiController class like this:[UnhandledExceptionFilter] public class AlbumRpcApiController : ApiController or you can globally assign it to all controllers by adding it to the HTTP Configuration's Filters collection:GlobalConfiguration.Configuration.Filters.Add(new UnhandledExceptionFilter()); The latter is a great way to get global error trapping so that all errors (short of hard IIS errors and explicit HttpResponseException errors) return a valid error response that includes error information in the form of a known-error object. Using a filter like this allows you to throw an exception as you normally would and have your filter create a response in the appropriate output format that the client expects. For example, an AJAX application can on failure expect to see a JSON error result that corresponds to the real error that occurred rather than a 500 error along with HTML error page that IIS throws up. You can even create some custom exceptions so you can differentiate your own exceptions from unhandled system exceptions - you often don't want to display error information from 'unknown' exceptions as they may contain sensitive system information or info that's not generally useful to users of your application/site. This is just one example of how ASP.NET Web API is configurable and extensible. Exception filters are just one example of how you can plug-in into the Web API request flow to modify output. Many more hooks exist and I’ll take a closer look at extensibility in Part 2 of this article in the future. Summary Web API is a big improvement over previous Microsoft REST and AJAX toolkits. The key features to its usefulness are its ease of use with simple controller based logic, familiar MVC-style routing, low configuration impact, extensibility at all levels and tight attention to exposing and making HTTP semantics easily discoverable and easy to use. Although none of the concepts used in Web API are new or radical, Web API combines the best of previous platforms into a single framework that’s highly functional, easy to work with, and extensible to boot. I think that Microsoft has hit a home run with Web API. Related Resources Where does ASP.NET Web API fit? Sample Source Code on GitHub Passing multiple POST parameters to Web API Controller Methods Mapping UrlEncoded POST Values in ASP.NET Web API Creating a JSONP Formatter for ASP.NET Web API Removing the XML Formatter from ASP.NET Web API Applications© Rick Strahl, West Wind Technologies, 2005-2012Posted in Web Api   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

    Read the article

  • Reading a Serial Port - Ignore portion of data written to serial port for certain time

    - by farmerjoe
    I would like to read data coming and Arduino on a serial port on intervals. So essentially something like Take a reading Wait Take a reading Wait Take ... etc. The problem I am facing is that the port will buffer its information so as soon as I call a wait function the data on the serial port will start buffering. Once the wait function finishes I try and read the data again but I am reading from the beginning of the buffer and the data is not current anymore, but instead is the reading taken at roughly the time the wait function began. My question is whether there is a way that I am unaware of to ignore the portion of data read in during that wait period and only read what is currently being delivered on the serial port? I have this something analogous to this so far: import serial s = serial.Serial(path_to_my_serial_port,9600) while True: print s.readline() time.sleep(.5) For explanation purposes I have the Arduino outputting the time since it began its loop. By the python code, the time of each call should be a half second apart. By the serial output the time is incrementing in less than a millisecond. These values do not change regardless of the sleep timing. Sample output: 504 504 504 504 505 505 505 ... As an idea of my end goal, I would like to measure the value of the port, wait a time delay, see what the value is then, wait again, see what the value is then, wait again. I am currently using Python for this but am open to other languages.

    Read the article

  • Measuring execution time of selected loops

    - by user95281
    I want to measure the running times of selected loops in a C program so as to see what percentage of the total time for executing the program (on linux) is spent in these loops. I should be able to specify the loops for which the performance should be measured. I have tried out several tools (vtune, hpctoolkit, oprofile) in the last few days and none of them seem to do this. They all find the performance bottlenecks and just show the time for those. Thats because these tools only store the time taken that is above a threshold (~1ms). So if one loop takes lesser time than that then its execution time won't be reported. The basic block counting feature of gprof depends on a feature in older compilers thats not supported now. I could manually write a simple timer using gettimeofday or something like that but for some cases it won't give accurate results. For ex: for (i = 0; i < 1000; ++i) { for (j = 0; j < N; ++j) { //do some work here } } Now here I want to measure the total time spent in the inner loop and I will have to put a call to gettimeofday inside the first loop. So gettimeofday itself will get called a 1000 times which introduces its own overhead and the result will be inaccurate.

    Read the article

  • Time complexity to fill hash table (homework)?

    - by Heathcliff
    This is a homework question, but I think there's something missing from it. It asks: Provide a sequence of m keys to fill a hash table implemented with linear probing, such that the time to fill it is minimum. And then Provide another sequence of m keys, but such that the time fill it is maximum. Repeat these two questions if the hash table implements quadratic probing I can only assume that the hash table has size m, both because it's the only number given and because we have been using that letter to address a hash table size before when describing the load factor. But I can't think of any sequence to do the first without knowing the hash function that hashes the sequence into the table. If it is a bad hash function, such that, for instance, it hashes every entry to the same index, then both the minimum and maximum time to fill it will take O(n) time, regardless of what the sequence looks like. And in the average case, where I assume the hash function is OK, how am I suppossed to know how long it will take for that hash function to fill the table? Aren't these questions linked to the hash function stronger than they are to the sequence that is hashed? As for the second question, I can assume that, regardless of the hash function, a sequence of size m with the same key repeated m-times will provide the maximum time, because it will cause linear probing from the second entry on. I think that will take O(n) time. Is that correct? Thanks

    Read the article

  • real time stock quotes, StreamReader performance optimization

    - by sean717
    I am working on a program that extracts real time quote for 900+ stocks from a website. I use HttpWebRequest to send HTTP request to the site and store the response to a stream and open a stream using the following code: HttpWebResponse response = (HttpWebResponse)request.GetResponse(); Stream stream = response.GetResponseStream (); StreamReader reader = new StreamReader( stream ) the size of the received HTML is large (5000+ lines), so it takes a long time to parse it and extract the price. For 900 files, It takes about 6 mins for parsing and extracting. Which my boss isn't happy with, he told me he'd want the whole process to be done in TWO mins. I've identified the part of the program that takes most of time to finish is parsing and extracting. I've tried to optimize the code to make it faster, the following is what I have now after some optimization: // skip lines at the top for(int i=0;i<1500;++i) reader.ReadLine(); // read the line that contains the price string theLine = reader.ReadLine(); // ... extract the price from the line now it takes about 4 mins to process all the files, there is still a significant gap to what my boss's expecting. So I am wondering, is there other way that I can further speed up the parsing and extracting and have everything done within 2 mins?

    Read the article

  • Can I get the amount of time for which a key is pressed on a keyboard

    - by Adi
    Dear all, I am working on a project in which I have to develop bio-passwords based on user's keystroke style. Suppose a user types a password for 20 times, his keystrokes are recorded, like holdtime : time for which a particular key is pressed. digraph time : time it takes to press a different key. suppose a user types a password " COMPUTER". I need to know the time for which every key is pressed. something like : holdtime for the above password is C-- 200ms O-- 130ms M-- 150ms P-- 175ms U-- 320ms T-- 230ms E-- 120ms R-- 300ms The rational behind this is , every user will have a different holdtime. Say a old person is typing the password, he will take more time then a student. And it will be unique to a particular person. To do this project, I need to record the time for each key pressed. I would greatly appreciate if anyone can guide me in how to get these times. Editing from here.. Language is not important, but I would prefer it in C. I am more interested in getting the dataset.

    Read the article

  • PHP date returning wrong time

    - by gargantaun
    The following script is returning the wrong time after I call date_default_timezone_set("UTC") <?PHP $timestamp = time(); echo "<p>Timestamp: $timestamp</p>"; // This returns the correct time echo "<p>". date("Y-m-d H:i:s", $timestamp) ."</p>"; echo "<p>Now I call 'date_default_timezone_set(\"UTC\")' and echo out the same timestamp.</p>"; echo "Set timezone = " . date_default_timezone_set("UTC"); // This returns a time 5 hours in the past echo "<p>". date("Y-m-d H:i:s", $timestamp) ."</p>"; ?> The timezone on the server is BST. So what should happen is that the second call to 'date' should return a time 1 hour behind the first call. It's actually returning a time 5 hours behind the first one. I should note that the server was originally set up with the EDT timezone (UTC -4). That was changed to BST (UTC +1) and the server was restarted. I can't figure out if this is a PHP problem or a problem with the server.

    Read the article

  • How to make freelance clients understand the costs of developing and maintaining mature products?

    - by John
    I have a freelance web application project where the client requests new features every two weeks or so. I am unable to anticipate the requirements of upcoming features. So when the client requests a new feature, one of several things may happen: I implement the feature with ease because it is compatible with the existing platform I implement the feature with difficulty because I have to rewrite a significant portion of the platform's foundation Client withdraws request because it costs too much to implement against existing platform At the beginning of the project, for about six months, all feature requests fell under category 1) because the system was small and agile. But for the past six months, most feature implementation fell under category 2). The system is mature, forcing me to refactor and test everytime I want to add new modules. Additionally, I find myself breaking things that use to work, and fixing it (I don't get paid for this). The client is starting to express frustration at the time and cost for me to implement new features. To them, many of the feature requests are of the same scale as the features they requested six months ago. For example, a client would ask, "If it took you 1 week to build a ticketing system last year, why does it take you 1 month to build an event registration system today? An event registration system is much simpler than a ticketing system. It should only take you 1 week!" Because of this scenario, I fear feature requests will soon land in category 3). In fact, I'm already eating a lot of the cost myself because I volunteer many hours to support the project. The client is often shocked when I tell him honestly the time it takes to do something. The client always compares my estimates against the early months of a project. I don't think they're prepared for what it really costs to develop, maintain and support a mature web application. When working on a salary for a full time company, managers were more receptive of my estimates and even encouraged me to pad my numbers to prepare for the unexpected. Is there a way to condition my clients to think the same way? Can anyone offer advice on how I can continue to work on this web project without eating too much of the cost myself? Additional info - I've only been freelancing full time for 1 year. I don't yet have the high end clients, but I'm slowly getting there. I'm getting better quality clients as time goes by.

    Read the article

  • Don&rsquo;t Miss &ldquo;Transform Field Service Delivery with Oracle Real-Time Scheduler&rdquo;

    - by ruth.donohue
    Field resources are an expensive element in the service equation. Maximizing the scheduling and routing of these resources is critical in reducing costs, increasing profitability, and improving the customer experience. Oracle Real-Time Scheduler creates cost-optimized plans and schedules for service technicians that increase operational efficiencies and improve margins. It enhances Oracle’s Siebel Field Service with real-time scheduling and dispatch capabilities that ensure service requests are allocated efficiently and service levels are honored. Join our live Webcast to learn how your organization can leverage Oracle Real-Time Scheduler to: Increase operational efficiency with real-time scheduling that enables field service technicians to handle more calls per day and reduce travel mileage Resolve issues faster with dynamic work flows that ensure you have the right technician with the right skill set for the right job Improve the customer experience with real-time planning that optimizes field technician routing, reduces customer wait times, and minimizes missed SLAs Date: Thursday, March 10, 2011 Time: 8:30 am PT / 11:30 am ET / 4:30 pm UK / 5:30 pm CET Click here to register now.   Technorati Tags: Siebel Field Service,Oracle Real-Time Scheduler

    Read the article

  • What time function do I need to use with pthread_cond_timedwait?

    - by Vincent
    The pthread_cond_timedwait function needs an absolute time in a time timespec structure. What time function I'm suppose to use to obtain the absolute time. I saw a lot of example on the web and I found almost all time function used. (ftime, clock, gettimeofday, clock_gettime (with all possible CLOCK_...). The pthread_cond_timedwait uses an absolute time. Will this waiting time affected by changing the time of the machine? Also if I get the absolute time with one of the time function, if the time of the machine change between the get and the addition of the delta time this will affect the affect the wait time? Is there a possibility to wait for an event with a relative time instead?

    Read the article

  • Salesforce/PHP - Bulk Outbound message (SOAP), Time out issue - See update #2

    - by Phill Pafford
    Salesforce can send up to 100 requests inside 1 SOAP message. While sending this type of Bulk Ooutbound message request my PHP script finishes executing but SF fails to accept the ACK used to clear the message queue on the Salesforce side of things. Looking at the Outbound message log (monitoring) I see all the messages in a pending state with the Delivery Failure Reason "java.net.SocketTimeoutException: Read timed out". If my script has finished execution, why do I get this error? I have tried these methods to increase the execution time on my server as I have no access on the Salesforce side: set_time_limit(0); // in the script max_execution_time = 360 ; Maximum execution time of each script, in seconds max_input_time = 360 ; Maximum amount of time each script may spend parsing request data memory_limit = 32M ; Maximum amount of memory a script may consume I used the high settings just for testing. Any thoughts as to why this is failing the ACK delivery back to Salesforce? Here is some of the code: This is how I accept and send the ACK file for the imcoming SOAP request $data = 'php://input'; $content = file_get_contents($data); if($content) { respond('true'); } else { respond('false'); } The respond function function respond($tf) { $ACK = <<<ACK <?xml version = "1.0" encoding = "utf-8"?> <soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <soapenv:Body> <notifications xmlns="http://soap.sforce.com/2005/09/outbound"> <Ack>$tf</Ack> </notifications> </soapenv:Body> </soapenv:Envelope> ACK; print trim($ACK); } These are in a generic script that I include into the script that uses the data for a specific workflow. I can process about 25 requests (That are in 1 SOAP response) but once I go over that I get the timeout error in the Salesforce queue. for 50 requests is usually takes my PHP script 86.77 seconds. Could it be Apache? PHP? I have also tested just accepting the 100 request SOAP response and just accepting and sending the ACK the queue clears out, so I know it's on my side of things. I show no errors in the apache log, the script runs fine. I did find some info on the Salesforce site but still no luck. Here is the link. Also I'm using the PHP Toolkit 11 (From Salesforce). Other forum with good SF help Thanks for any insight into this, --Phill UPDATE: If I receive the incoming message and print the response, should this happen first regardless if I do anything else after? Or does it wait for my process to finish and then print the response? UPDATE #2: okay I think I have the problem: PHP uses the single thread processing approach and will not send back the ACK file until the thread has completed it's processing. Is there a way to make this a mutli thread process? Thread #1 - accept the incoming SOAP request and send back the ACK Thread #2 - Process the SOAP request I know I could break it up into like a DB table or flat file, but is there a way to accomplish this without doing that? I'm going to try to close the socket after the ACK submission and continue the processing, cross my fingers it will work.

    Read the article

  • How to catch an expected (and intended) 302 response code with generic XmlHttpRequest?

    - by Anthony
    So, if you look back at my previous question about Exchange Autodiscover, you'll see that the easiet way to get the autodiscover URL is to send a non-secure, non-authenticated GET request to the server, ala: http://autodiscover.exchangeserver.org/autodiscover/autodiscover.xml The server will respond with a 302 redirect with the correct url in the Location header. I'm trying out something really simple at first with a Chrome extension, where I have: if (req.readyState==4 && req.status==302) { return req.getResponseHeader("Location"); } With another ajax call set up with the full XML Post and the user credentials, But instead Chrome hangs at this point, and a look at the developer panel shows that it is not returning back the response but instead is acting like no response was given, meanwhile showing a Uncaught Error: NETWORK_ERR: XMLHttpRequest Exception 101 in the error log. The way I see it, refering to the exact response status is about the same as "catching" it, but I'm not sure if the problem is with Chrome/WebKit or if this is how XHR requests always handle redirects. I'm not sure how to catch this so that I can get still get the headers from the response. Or would it be possible to set up a secondary XHR such that when it gets the 302, it sends a totally different request? Quick Update I just changed it so that it doesn't check the response code: if (req.readyState==4) { return req.getResponseHeader("Location"); } and instead when I alert out the value it's null. and there is still the same error and no response in the dev console. SO it seems like it either doesn't track 302 responses as responses, or something happens after that wipes that response out?

    Read the article

  • Getting a nicely formatted timestamp without lots of overhead?

    - by Brad Hein
    In my app I have a textView which contains real-time messages from my app, as things happen, messages get printed to this text box. Each message is time-stamped with HH:MM:SS. Up to now, I had also been chasing what seemed to be a memory leak, but as it turns out, it's just my time-stamp formatting method (see below), It apparently produces thousands of objects that later get gc'd. For 1-10 messages per second, I was seeing 500k-2MB of garbage collected every second by the GC while this method was in place. After removing it, no more garbage problem (its back to a nice interval of about 30 seconds, and only a few k of junk typically) So I'm looking for a new, more lightweight method for producing a HH:MM:SS timestamp string :) Old code: /** * Returns a string containing the current time stamp. * @return - a string. */ public static String currentTimeStamp() { String ret = ""; Date d = new Date(); SimpleDateFormat timeStampFormatter = new SimpleDateFormat("hh:mm:ss"); ret = timeStampFormatter.format(d); return ret; }

    Read the article

  • How to catch an expected (and intended) 302 Ajax response?

    - by Anthony
    So, if you look back at my previous question about Exchange Autodiscover, you'll see that the easiet way to get the autodiscover URL is to send a non-secure, non-authenticated GET request to the server, ala: http://autodiscover.exchangeserver.org/autodiscover/autodiscover.xml The server will respond with a 302 redirect with the correct url in the Location header. I'm trying out something really simple at first with a Chrome extension, where I have: if (req.readyState==4 && req.status==302) { return req.getResponseHeader("Location"); } With another ajax call set up with the full XML Post and the user credentials, But instead Chrome hangs at this point, and a look at the developer panel shows that it is not returning back the response but instead is acting like no response was given, meanwhile showing a Uncaught Error: NETWORK_ERR: XMLHttpRequest Exception 101 in the error log. The way I see it, refering to the exact response status is about the same as "catching" it, but I'm not sure if the problem is with Chrome/WebKit or if this is how XHR requests always handle redirects. I'm not sure how to catch this so that I can get still get the headers from the response. Or would it be possible to set up a secondary XHR such that when it gets the 302, it sends a totally different request? Quick Update I just changed it so that it doesn't check the response code: if (req.readyState==4) { return req.getResponseHeader("Location"); } and instead when I alert out the value it's null. and there is still the same error and no response in the dev console. SO it seems like it either doesn't track 302 responses as responses, or something happens after that wipes that response out?

    Read the article

  • Android while getting HTTP response to file how to know it wasn't fully loaded?

    - by Stan
    I'm using this approach to store a big-sized response from server to parse it later: final HttpClient client = new DefaultHttpClient(new BasicHttpParams()); final HttpGet mHttpGetRequest = new HttpGet(strUrl); mHttpGetRequest.setHeader("Content-Type", "application/x-www-form-urlencoded"); FileOutputStream fos = null; try { final HttpResponse response = client.execute(mHttpGetRequest); final StatusLine statusLine = response.getStatusLine(); lastHttpErrorCode = statusLine.getStatusCode(); lastHttpErrorMsg = statusLine.getReasonPhrase(); if (lastHttpErrorCode == 200) { HttpEntity entity = response.getEntity(); fos = new FileOutputStream(reponseFile); entity.writeTo(fos); entity.consumeContent(); fos.flush(); } } catch (ClientProtocolException e) { e.printStackTrace(); lastHttpErrorMsg = e.toString(); return null; } catch (final ParseException e) { e.printStackTrace(); lastHttpErrorMsg = e.toString(); return null; } catch (final UnknownHostException e) { e.printStackTrace(); lastHttpErrorMsg = e.toString(); return null; } catch (IOException e) { e.printStackTrace(); lastHttpErrorMsg = e.toString(); } finally{ if (fos!=null) try{ fos.close(); } catch (IOException e){} } now how could I ensure the response was completely received and thus saved to file? Assume client's device lost Internet connection while this code was running. So the app received only some part of real response. And I'm pretty sure it happens cuz I got parsing exceptions like "tag not closed", "unexpected end of file" etc. So I need to detect somehow this situation to prevent code from parsing partial response but can't see how. Is it possible at all and how to do it? Or has it has to raise IOException in such cases?

    Read the article

  • svchost consuming more than 50% CPU all the time in windows 7

    - by claws
    Hello, I'm using windows 7 ultimate. svchost containing DCOM Server Process Launcher Plug and Play Power services is consuming more than 50% of CPU for most of the time. I found this blog post: http://blog.hansmelis.be/2007/06/17/windows-vista-long-delay-when-switching-songs-in-media-player/ That process is associated with two services: DCOM Server Process Launcher and Plug and Play. For the Vulcans among us, all logic stops there for a second. What do those two services have to do with WMP? The answer is provided by Vista's new audio engine. The new engine supports several audio "enhancements". But for the enhancements to work, the engine needs to determine if your hardware is up to the task. And when does it check that? Each time a sound output device is accessed. That's pretty nice if you can do a hot swap of sound hardware, but I don't see me doing that anytime soon. Anyways, it does provide us with the link to the correct service because checking hardware is done by the "Plug and Play" service. One might think that deactivating each enhancement would solve the problem, but that's wishful thinking. The configuration of the enhancements is located in the properties of the sound hardware. When opening the tab, I found out that no enhancements were active. Hmmm... so why does it check the hardware? Well, it does that in case you actually enable an enhancement. To completely stop the hardware checking, you have to tick the box labelled Disable all enhancements. As soon as you do that, Vista finally understands you don't want to use them buts thats for vista. Is it the same case with windows 7 too? and I couldn't find any "Disable all enhancements" in my controlpanelsounds (mmsys.cpl). Where can I find this option in windows 7? How to solve this?

    Read the article

  • time sync with ntpd

    - by guthrie
    I run Debian on several systems, and their times do not seem to stay in sync. I can run ntpdate manually, but I thought that I should have an ntpd running that would automate that. I did check with apt and apt-cache but don't find any ntpd (or associated ntpq), not any such names in my system (locate...), but ntp-doc does still describe them. Looking around I see that there is an ntpdate-debian command, and it uses /etc/default/ntpdate for servers (instead of the standard /etc/ntp.conf), but even thought that file is there and has "yes" indicated to use ntp.conf, it fails with "no servers can be used", although ntpdate works fine. Is this just a layer over ntpdate, any reason to use it instead? So, why are they missing, do I need them, how do I automate time updates? Associated, two of my machines are virtualized on a MSoft VM, how is it that their clocks drift, and both to different values? (The underlying Windows machine clock seems stable). I see a few old notes about time & ntp problems on VMware, didn't find anything either current or relating to MSoft VMs. Anything I did see says just to use ntpd, but as above, ...?!

    Read the article

  • It takes a long time until Windows XP recognize I connected USB drive

    - by Pavol G
    I have a problem with my new USB disk. When I connect it to my laptop with Windows XP SP2 it takes about 4-5min until Windows recognizes it and shows it as a new disk. I can also see (disk's LED is blinking) that something is scanning the disk when I connect it; when this is done Windows immediately recognize it. Also when I'm copying data to this disk the speed is about 3.5MB/sec. It's connected using USB2.0. I tried to check for spyware (using Spybot), also tried running Windows in safe mode. But still have the same problems. Do you have any idea what could help to solve this problem? On Windows Vista (another laptop) everything is ok, disk loads in about 15sec and speed is about 20-30MB/sec. Edit: I tried to update to SP3 - no change Edit2: When this "strange" scanning occurs I can see that DPCs process is taking about 50% of CPU. When the scan ends (after 5min) this process take 0% again. Edit3: About the scan time, currently it's taking about 5min, but this time is growing as I'm adding more data to the disk, currently its about 40GB and I don't want to see how long it will take with 1000GB. Thanks a lot for every advice!

    Read the article

  • Apache LDAP auth: denied all time

    - by Dmytro
    There is my config (httpd 2.4): <AuthnProviderAlias ldap zzzldap> LDAPReferrals Off AuthLDAPURL "ldaps://ldap.zzz.com:636/o=zzz.com?uid?sub?(objectClass=*)" AuthLDAPBindDN "uid=zzz,ou=Applications,o=zzz.com" AuthLDAPBindPassword "zzz" </AuthnProviderAlias> <Location /svn> DAV svn SVNParentPath /DATA/svn AuthType Basic AuthName "Subversion repositories" SSLRequireSSL AuthBasicProvider zzzldap <RequireAll> Require valid-user Require ldap-attribute employeeNumber=12345 Require ldap-group cn=yyy,ou=Groups,o=zzz.com </RequireAll> </Location> The Require valid-user is work. But ldap-attribite, ldap-filter, ldap-group does not work - denied in logs all time. I spent a lot of time but can't understand what's going on. This is the example of my logs: [Tue Sep 25 16:42:26.772006 2012] [authz_core:debug] [pid 23087:tid 139684003014400] mod_authz_core.c(802): [client 1.1.1.1:52624] AH01626: authorization result of Require valid-user : granted [Tue Sep 25 16:42:26.772014 2012] [authz_core:debug] [pid 23087:tid 139684003014400] mod_authz_core.c(802): [client 1.1.1.1:52624] AH01626: authorization result of Require ldap-attribute employeeNumber=12345: denied I checked all info with ldapsearch: there is a valid username, employee ID and other...

    Read the article

  • Snow Leopard takes a long time to connect to Windows/Samba server

    - by hood
    We run a very heterogeneous network here: There is some XP, Vista, 7, Leopard, Snow Leopard clients, and Windows 2003 (one remaining legacy app), 2008, and Linux servers. The main file server runs Ubuntu Linux and has been added to the Windows Domain and has been used for many years; SBS 2008 is the PDC (the 2003 and 2008 are on the domain also). In Leopard there were no problems at all authenticating to the file servers. We've upgraded one of the Leopard iMacs to Snow Leopard, though the same problem occurs in a new MBP which came with the newer OS as well as a clean install on another iMac. It does not matter whether connected through wired or wireless. In the Finder when clicking on the server - whether on first boot or after it is connected - it will display "Connecting..." for up to a few minutes before either generally working (if username/password in keychain) or displaying "Connection Failed" - at which time clicking "Connect As" and typing in the username/password will take some more time and eventually work. Sometimes it will display "Connecting..." indefinitely. (I've left it as long as 15 minutes before trying something else) Accessing shares on the the 2003 and SBS servers have the problem (so I don't think it's a Samba server issue). The Server 2008 Standard is connecting instantly at the moment. Accessing the share through an alias/stacks doesn't have this problem. Leopard and Windows clients still have no problem. I've searched Google but hasn't yielded any working result. How do I get rid of this delay?

    Read the article

  • Long access time for static web page on virtual machine

    - by Karol
    My setup Windows 7 on workstation that I use at work (with domain) and home (no domain) Virtual machine (VMWare) that runs Arch Linux (I will call it just "Linux") with network interface in bridged mode. Linux serves web pages with Nginx. IP address of Linux machine is 192.168.0.16 and is added to C:\windows\system32\drivers\etc\hosts: 192.168.0.16 bridged bri IP address of Windows workstation is added to /etc/hosts: 192.168.0.10 workstation I can add more details to my setup description (I am not sure what is relevant). The question Often (but not always) it takes long time for a web browser (Firefox) to open static web page served by Linux. I am sure it is not a performance issue. To be more specific: it takes about ~20 seconds to resolve(?) the address http://bridged for a web browser. Additionally I have just installed samba service and noticed similar problem, so it is not specific to browser & http. Initial access for samba shares also takes long time.

    Read the article

  • Very long (>300s) request processing time on Apache Server serving static content from particular IP

    - by Ron Bieber
    We are running an Apache 2.2 server for a very large web site. Over the past few months we have been having some users reporting slow response times, while others (including our resources, both on the internal network and our home networks) do not see any degradation in performance. After a ton of investigation, we finally found a "Deny from none" statement in our configuration that was causing reverse DNS lookups (which were timing out) that solved the bulk of our issues, but we still have some customers that we are seeing in the Apache logs (using %D in the log format) with request processing times of 300s for images, css, javascript and other static content. We've checked all Deny / Allow statements for reoccurrence of "none", as well as all other things we know of that would cause reverse DNS lookups (such as using "REMOTE_HOST" in rewrite rules, using %a instead of %h in our log format configuration) as well as verified that HostnameLookups is set to "Off". As an aside, we've also validated that reverse DNS lookups for folks having this problem do not time out - so I'm fairly certain DNS is not an issue in this case. I've run out of ideas. Are there any Apache configuration scenarios that someone can point me to that I might be missing that would cause request times for static content to take so long only for certain users? Thank you in advance.

    Read the article

  • How to use multiple variables in time calculator c#

    - by Peter O'Dwyer
    I am building a video time calculator and need to use the number of frames instead of milliseconds. e.g 25FPS HH:MM:SS:FR 00:00:10:24 <-- Last frame of 10 seconds 00:00:11:00 <-- First frame of 11 seconds My problem is that if the start frames are lower than my end frames it can't calculate the time. 00:00:10:05 <-- Start 01:00:10:10 <-- End 00:59:59:05 <-- Answer which I can't get!! HERE'S MY CODE string Startdate = Dur_txtStart.Text; string Enddate = Dur_txtEnd.Text; string Startdate1 = Startdate.Substring(0, 8); int Startframe1 = Convert.ToInt32(Startdate.Substring(9, 2)); string Startdate2 = Enddate.Substring(0, 8); int Startframe2= Convert.ToInt32(Enddate.Substring(9, 2)); TimeSpan diff = DateTime.Parse(Startdate2).Subtract(DateTime.Parse(Startdate1)); int frameDiff = Startframe2 - Startframe1; int Hour = Convert.ToInt32(diff.Hours); int Min = Convert.ToInt32(diff.Minutes); int Sec = Convert.ToInt32(diff.Seconds); if (frameDiff < 0 && Sec > 0) { Sec -= 1; string frameDiffBuild = string.Format("{0}:{1}:{2}:{3}",Hour.ToString("D2"), Min.ToString("D2"), Sec.ToString("D2"), (Convert.ToInt32(Dur_txtFPS.Text + frameDiff)).ToString("D2")); Dur_txtOutTime.Text = frameDiffBuild; } else { string frameDiffBuild = string.Format("{0}:{1}:{2}:{3}",Hour.ToString("D2"), Min.ToString("D2"), Sec.ToString("D2"), frameDiff.ToString("D2")); Dur_txtOutTime.Text = frameDiffBuild; } Hope you can help guys my head is mashed!

    Read the article

< Previous Page | 91 92 93 94 95 96 97 98 99 100 101 102  | Next Page >