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• Logging WebSocket Frames using Chrome Developer Tools, Net-internals and Wireshark (TOTD #184)

  - by arungupta

  TOTD #183 explained how to build a WebSocket-driven application using GlassFish 4. This Tip Of The Day (TOTD) will explain how do view/debug on-the-wire messages, or frames as they are called in WebSocket parlance, over this upgraded connection. This blog will use the application built in TOTD #183. First of all, make sure you are using a browser that supports WebSocket. If you recall from TOTD #183 then WebSocket is combination of Protocol and JavaScript API. A browser supporting WebSocket, or not, means they understand your web pages with the WebSocket JavaScript. caniuse.com/websockets provide a current status of WebSocket support in different browsers. Most of the major browsers such as Chrome, Firefox, Safari already support WebSocket for the past few versions. As of this writing, IE still does not support WebSocket however its planned for a future release. Viewing WebSocket farmes require special settings because all the communication happens over an upgraded HTTP connection over a single TCP connection. If you are building your application using Java, then there are two common ways to debug WebSocket messages today. Other language libraries provide different mechanisms to log the messages. Lets get started! Chrome Developer Tools provide information about the initial handshake only. This can be viewed in the Network tab and selecting the endpoint hosting the WebSocket endpoint. You can also click on "WebSockets" on the bottom-right to show only the WebSocket endpoints. Click on "Frames" in the right panel to view the actual frames being exchanged between the client and server. The frames are not refreshed when new messages are sent or received. You need to refresh the panel by clicking on the endpoint again. To see more detailed information about the WebSocket frames, you need to type "chrome://net-internals" in a new tab. Click on "Sockets" in the left navigation bar and then on "View live sockets" to see the page. Select the box with the address to your WebSocket endpoint and see some basic information about connection and bytes exchanged between the client and the endpoint. Clicking on the blue text "source dependency ..." shows more details about the handshake. If you are interested in viewing the exact payload of WebSocket messages then you need a network sniffer. These tools are used to snoop network traffic and provide a lot more details about the raw messages exchanged over the network. However because they provide lot more information so they need to be configured in order to view the relevant information. Wireshark (nee Ethereal) is a pretty standard tool for sniffing network traffic and will be used here. For this blog purpose, we'll assume that the WebSocket endpoint is hosted on the local machine. These tools do allow to sniff traffic across the network though. Wireshark is quite a comprehensive tool and we'll capture traffic on the loopback address. Start wireshark, select "loopback" and click on "Start". By default, all traffic information on the loopback address is displayed. That includes tons of TCP protocol messages, applications running on your local machines (like GlassFish or Dropbox on mine), and many others. Specify "http" as the filter in the top-left. Invoke the application built in TOTD #183 and click on "Say Hello" button once. The output in wireshark looks like Here is a description of the messages exchanged: Message #4: Initial HTTP request of the JSP page Message #6: Response returning the JSP page Message #16: HTTP Upgrade request Message #18: Upgrade request accepted Message #20: Request favicon Message #22: Responding with favicon not found Message #24: Browser making a WebSocket request to the endpoint Message #26: WebSocket endpoint responding back You can also use Fiddler to debug your WebSocket messages. How are you viewing your WebSocket messages ? Here are some references for you: JSR 356: Java API for WebSocket - Specification (Early Draft) and Implementation (already integrated in GlassFish 4 promoted builds) TOTD #183 - Getting Started with WebSocket in GlassFish Subsequent blogs will discuss the following topics (not necessary in that order) ... Binary data as payload Custom payloads using encoder/decoder Error handling Interface-driven WebSocket endpoint Java client API Client and Server configuration Security Subprotocols Extensions Other topics from the API

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• Archiving SQLHelp tweets

  - by jamiet

  #SQLHelp is a Twitter hashtag that can be used by any Twitter user to get help from the SQL Server community. I think its fair to say that in its first year of being it has proved to be a very useful resource however Kendra Little (@kendra_little) made a very salient point yesterday when she tweeted: Is there a way to search the archives of #sqlhelp Trying to remember answer to a question I know I saw a couple months ago http://twitter.com/#!/Kendra_Little/status/15538234184441856 This highlights an inherent problem with Twitter’s search capability – it simply does not reach far enough back in time. I have made steps to remedy that situation by putting into place two initiatives to archive Tweets that contain the #sqlhelp hashtag. The Archivist http://archivist.visitmix.com/ is a free service that, quite simply, archives a history of tweets that contain a given search term by periodically polling Twitter’s search service with that search term and subsequently displaying a dashboard providing an aggregate view of those tweets for things like tweet volume over time, top users and top words (Archivist FAQ). I have set up an archive on The Archivist for “sqlhelp” which you can view at http://archivist.visitmix.com/jamiet/7. Here is a screenshot of the SQLHelp dashboard 36 minutes after I set it up: There is lots of good information in there, including the fact that Jonathan Kehayias (@SQLSarg) is the most active SQLHelp tweeter (I suspect as an answerer rather than a questioner ) and that SSIS has proven to be a rather (ahem) popular subject!! Datasift The Archivist has its uses though for our purposes it has a couple of downsides. For starters you cannot search through an archive (which is what Kendra was after) and nor can you export the contents of the archive for offline analysis. For those functions we need something a bit more heavyweight and for that I present to you Datasift. Datasift is a tool (currently an alpha release) that allows you to search for tweets and provide them through an object called a Datasift stream. That sounds very similar to normal Twitter search though it has one distinct advantage that other Twitter search tools do not – Datasift has access to Twitter’s Streaming API (aka the Twitter Firehose). In addition it has access to a lot of other rather nice features: It provides the Datasift API that allows you to consume the output of a Datasift stream in your tool of choice (bring on my favourite ultimate mashup tool J ) It has a query language (called Filtered Stream Definition Language – FSDL for short) A Datasift stream can consume (and filter) other Datasift streams Datasift can (and does) consume services other than Twitter If I refer to Datasift as “ETL for tweets” then you may get some sort of idea what it is all about. Just as I did with The Archivist I have set up a publicly available Datasift stream for “sqlhelp” at http://datasift.net/stream/1581/sqlhelp. Here is the FSDL query that provides the data: twitter.text contains "sqlhelp" Pretty simple eh? At the current time it provides little more than a rudimentary dashboard but as Datasift is currently an alpha release I think this may be worth keeping an eye on. The real value though is the ability to consume the output of a stream via Datasift’s RESTful API, observe: http://api.datasift.net/stream.xml?stream_identifier=c7015255f07e982afdeebdf1ae6e3c0d&username=jamiet&api_key=XXXXXXX (Note that an api_key is required during the alpha period so, given that I’m not supplying my api_key, this URI will not work for you) Just to prove that a Datasift stream can indeed consume data from another stream I have set up a second stream that further filters the first one for tweets containing “SSIS”. That one is at http://datasift.net/stream/1586/ssis-sqlhelp and here is the FSDL query: rule "414c9845685ff8d2548999cf3162e897" and (interaction.content contains "ssis") When Datasift moves beyond alpha I’ll re-assess how useful this is going to be and post a follow-up blog. @Jamiet

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• JavaOne Latin America 2012 Trip Report

  - by reza_rahman

  JavaOne Latin America 2012 was held at the Transamerica Expo Center in Sao Paulo, Brazil on December 4-6. The conference was a resounding success with a great vibe, excellent technical content and numerous world class speakers. Some notable local and international speakers included Bruno Souza, Yara Senger, Mattias Karlsson, Vinicius Senger, Heather Vancura, Tori Wieldt, Arun Gupta, Jim Weaver, Stephen Chin, Simon Ritter and Henrik Stahl. Topics covered included the JCP/JUGs, Java SE 7, HTML 5/WebSocket, CDI, Java EE 6, Java EE 7, JSF 2.2, JMS 2, JAX-RS 2, Arquillian and JavaFX. Bruno Borges and I manned the GlassFish booth at the Java Pavilion on Tuesday and Webnesday. The booth traffic was decent and not too hectic. We met a number of GlassFish adopters including perhaps one of the largest GlassFish deployments in Brazil as well as some folks migrating to Java EE from Spring. We invited them to share their stories with us. We also talked with some key members of the local Java community. Tuesday evening we had the GlassFish party at the Tribeca Pub. The party was definitely a hit and we could have used a larger venue (this was the first time we had the GlassFish party in Brazil). Along with GlassFish enthusiasts, a number of Java community leaders were there. We met some of the same folks again at the JUG leader's party on Wednesday evening. On Thursday Arun Gupta, Bruno Borges and I ran a hands-on-lab on JAX-RS, WebSocket and Server-Sent Events (SSE) titled "Developing JAX-RS Web Applications Utilizing Server-Sent Events and WebSocket". This is the same Java EE 7 lab run at JavaOne San Francisco. The lab provides developers a first hand glipse of how an HTML 5 powered Java EE application might look like. We had an overflow crowd for the lab (at one point we had about twenty people standing) and the lab went very well. The slides for the lab are here: Developing JAX-RS Web Applications Utilizing Server-Sent Events and WebSocket from Reza Rahman The actual contents for the lab is available here. Give me a shout if you need help getting it up and running. I gave two solo talks following the lab. The first was on JMS 2 titled "What’s New in Java Message Service 2". This was essentially the same talk given by JMS 2 specification lead Nigel Deakin at JavaOne San Francisco. I talked about the JMS 2 simplified API, JMSContext injection, delivery delays, asynchronous send, JMS resource definition in Java EE 7, standardized configuration for JMS MDBs in EJB 3.2, mandatory JCA pluggability and the like. The session went very well, there was good Q & A and someone even told me this was the best session of the conference! The slides for the talk are here: What’s New in Java Message Service 2 from Reza Rahman My last talk for the conference was on JAX-RS 2 in the keynote hall. Titled "JAX-RS 2: New and Noteworthy in the RESTful Web Services API" this was basically the same talk given by the specification leads Santiago Pericas-Geertsen and Marek Potociar at JavaOne San Francisco. I talked about the JAX-RS 2 client API, asyncronous processing, filters/interceptors, hypermedia support, server-side content negotiation and the like. The talk went very well and I got a few very kind complements afterwards. The slides for the talk are here: JAX-RS 2: New and Noteworthy in the RESTful Web Services API from Reza Rahman On a more personal note, Sao Paulo has always had a special place in my heart as the incubating city for Sepultura and Soulfy -- two of my most favorite heavy metal musical groups of all time! Consequently, the city has a perpertually alive and kicking metal scene pretty much any given day of the week. This time I got to check out a solid performance by local metal gig Republica at the legendary Manifesto Bar. I also wanted to see a Dio Tribute at the Blackmore but ran out of time and energy... Overall I enjoyed the conference/Sao Paulo and look forward to going to Brazil again next year!

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• How to prepare for a programming competition? Graphs, Stacks, Trees, oh my! [closed]

  - by Simucal

  Last semester I attended ACM's (Association for Computing Machinery) bi-annual programming competition at a local University. My University sent 2 teams of 3 people and we competed amongst other schools in the mid-west. We got our butts kicked. You are given a packet with about 11 problems (1 problem per page) and you have 4 hours to solve as many as you can. They'll run your program you submit against a set of data and your output must match theirs exactly. In fact, the judging is automated for the most part. In any case.. I went there fairly confident in my programming skills and I left there feeling drained and weak. It was a terribly humbling experience. In 4 hours my team of 3 people completed only one of the problems. The top team completed 4 of them and took 1st place. The problems they asked were like no problems I have ever had to answer before. I later learned that in order to solve them some of them effectively you have to use graphs/graph algorithms, trees, stacks. Some of them were simply "greedy" algo's. My question is, how can I better prepare for this semesters programming competition so I don't leave there feeling like a complete moron? What tips do you have for me to be able to answer these problems that involve graphs, trees, various "well known" algorithms? How can I easily identify the algorithm we should implement for a given problem? I have yet to take Algorithm Design in school so I just feel a little out of my element. Here are some examples of the questions asked at the competitions: ACM Problem Sets Update: Just wanted to update this since the latest competition is over. My team placed 1st for our small region (about 6-7 universities with between 1-5 teams each school) and ~15th for the midwest! So, it is a marked improvement over last years performance for sure. We also had no graduate students on our team and after reviewing the rules we found out that many teams had several! So, that would be a pretty big advantage in my own opinion. Problems this semester ranged from about 1-2 "easy" problems (ie bit manipulation, string manipulation) to hard (graph problems involving fairly complex math and network flow problems). We were able to solve 4 problems in our 5 hours. Just wanted to thank everyone for the resources they provided here, we used them for our weekly team practices and it definitely helped! Some quick tips that I have that aren't suggested below: When you are seated at your computer before the competition starts, quickly type out various data structures that you might need that you won't have access to in your languages libraries. I typed out a Graph data-structure complete with floyd-warshall and dijkstra's algorithm before the competition began. We ended up using it in our 2nd problem that we solved and this is the main reason why we solved this problem before anyone else in the midwest. We had it ready to go from the beginning. Similarly, type out the code to read in a file since this will be required for every problem. Save this answer "template" someplace so you can quickly copy/paste it to your IDE at the beginning of each problem. There are no rules on programming anything before the competition starts so get any boilerplate code out the way. We found it useful to have one person who is on permanent whiteboard duty. This is usually the person who is best at math and at working out solutions to get a head start on future problems you will be doing. One person is on permanent programming duty. Your fastest/most skilled "programmer" (most familiar with the language). This will save debugging time also. The last person has several roles between assessing the packet of problems for the next "easiest" problem, helping the person on the whiteboard work out solutions and helping the person programming work out bugs/issues. This person needs to be flexible and be able to switch between roles easily.

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• Tyrus 1.8

  - by Pavel Bucek

  Another version of Tyrus, the reference implementation of JSR 356 – Java API for WebSocket is out! Complete list of fixes and features is below, but let me describe some of the new features in more detail. All information presented here is also available in Tyrusdocumentation. What’s new? First to mention is that JSR 356 Maintenance review Ballot is over and the change proposed for 1.1 release was accepted. More details about changes in the API can be found in this article. Important part is that Tyrus 1.8 implements this API, meaning you can use Lambda expressions and some features of Nashorn without the need for any workarounds. Almost all other features are related to client side support, which was significantly improved in this release. Firstly – I have to admit, that Tyrus client contained security issue – SSL Hostname verification was not performed when connecting to “wss” endpoints. This was fixed as part of TYRUS-339 and resulted in some changes in the client configuration API. Now you can control whether HostnameVerification should be performed (SslEngineConfigurator#setHostnameVerificationEnabled(boolean)) or even set your own HostnameVerifier (please use carefully): #setHostnameVerifier(…). Detailed description can be found in Host verification chapter. Another related enhancement is support for Http Basic and Digest authentication schemes. Tyrus client now enables users to provide credentials and underlying implementation will take care of everything else. Our implementation is strictly non pre-emptive, so the login information is sent always as a response to 401 Http Status Code. If the Basic and Digest are not good enough and there is a need to use some custom scheme or something which is not yet supported in Tyrus, custom Authenticator can be registered and the authentication part of the handshake process will be handled by it. Please seeClient HTTP Authentication chapter in the user guide for more details. There are other features, like fine-grain threadpool configuration for JDK client container, build-in Http redirect support and some reshuffling related to unifying the location of client configuration classes and properties definition – every property should be now part of ClientProperties class. All new features are described in the user guide – in chapterTyrus proprietary configuration. Update – Tyrus 1.8.1 There was another slightly late reported issue related to running in environments with SecurityManager enabled, so this version fixes that. Another noteworthy fixes are TYRUS-355 and TYRUS-361; the first one is about incorrect thread factory used for shared container timeout, which resulted in JVM waiting for that thread and not exiting as it should. The other issue enables relative URIs in Location header when using redirect feature. Links Tyrus homepage mailing list JIRA Complete list of changes: Bug [TYRUS-333] – Multiple endpoints on one client [TYRUS-334] – When connection is closed by a peer, periodic heartbeat pong is not stopped [TYRUS-336] – ReaderBuffer.getNextChars() keeps blocking a server thread after client has closed the session [TYRUS-338] – JDK client SSL filter needs better synchronization during handshake phase [TYRUS-339] – SSL hostname verification is missing [TYRUS-340] – Test PathParamTest are not stable with JDK client [TYRUS-341] – A control frame inside a stream of continuation frames is treated as the part of the stream [TYRUS-343] – ControlFrameInDataStreamTest does not pass on GF [TYRUS-345] – NPE is thrown, when shared container timeout property in JDK client is not set [TYRUS-346] – IllegalStateException is thrown, when using proxy in JDK client [TYRUS-347] – Introduce better synchronization in JDK client thread pool [TYRUS-348] – When a client and server close connection simultaneously, JDK client throws NPE [TYRUS-356] – Tyrus cannot determine the connection port for a wss URL [TYRUS-357] – Exception thrown in MessageHandler#OnMessage is not caught in @OnError method [TYRUS-359] – Client based on Java 7 Asynchronous IO makes application unexitable Improvement [TYRUS-328] – JDK 1.7 AIO Client container – threads – (setting threadpool, limits, …) [TYRUS-332] – Consolidate shared client properties into one file. [TYRUS-337] – Create an SSL version of Basic Servlet test New Feature [TYRUS-228] – Add client support for HTTP Basic/Digest Task [TYRUS-330] – create/run tests/servlet/basic via wss [TYRUS-335] – [clustering] – introduce RemoteSession and expose them via separate method (not include remote sessions in the getOpenSessions()) [TYRUS-344] – Introduce Client support for HTTP Redirect

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• Is this Hybrid of Interface / Composition kosher?

  - by paul

  I'm working on a project in which I'm considering using a hybrid of interfaces and composition as a single thing. What I mean by this is having a contain*ee* class be used as a front for functionality implemented in a contain*er* class, where the container exposes the containee as a public property. Example (pseudocode): class Visibility(lambda doShow, lambda doHide, lambda isVisible) public method Show() {...} public method Hide() {...} public property IsVisible public event Shown public event Hidden class SomeClassWithVisibility private member visibility = new Visibility(doShow, doHide, isVisible) public property Visibility with get() = visibility private method doShow() {...} private method doHide() {...} private method isVisible() {...} There are three reasons I'm considering this: The language in which I'm working (F#) has some annoyances w.r.t. implementing interfaces the way I need to (unless I'm missing something) and this will help avoid a lot of boilerplate code. The containee classes could really be considered properties of the container class(es); i.e. there seems to be a fairly strong has-a relationship. The containee classes will likely implement code which would have been pretty much the same when implemented in all the container classes, so why not do it once in one place? In the above example, this would include managing and emitting the Shown/Hidden events. Does anyone see any isseus with this Composiface/Intersition method, or know of a better way? EDIT 2012.07.26 - It seems a little background information is warranted: Where I work, we have a bunch of application front-ends that have limited access to system resources -- they need access to these resources to fully function. To remedy this we have a back-end application that can access the needed resources, with which the front-ends can communicate. (There is an API written for the front-ends for accessing back-end functionality as though it were part of the front-end.) The back-end program is out of date and its functionality is incomplete. It has made the transition from company to company a couple of times and we can't even compile it anymore. So I'm trying to rewrite it in my spare time. I'm trying to update things to make a nice(r) interface/API for the front-ends (while allowing for backwards compatibility with older front-ends), hopefully something full of OOPy goodness. The thing is, I don't want to write the front-end API after I've written pretty much the same code in F# for implementing the back-end; so, what I'm planning on doing is applying attributes to classes/methods/properties that I would like to have code for in the API then generate this code from the F# assembly using reflection. The method outlined in this question is a possible alternative I'm considering instead of implementing straight interfaces on the classes in F# because they're kind of a bear: In order to access something of an interface that has been implemented in a class, you have to explicitly cast an instance of that class to the interface type. This would make things painful when getting calls from the front-ends. If you don't want to have to do this, you have to call out all of the interface's methods/properties again in the class, outside of the interface implementation (which is separate from regular class members), and call the implementation's members. This is basically repeating the same code, which is what I'm trying to avoid!

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• Custom Text and Binary Payloads using WebSocket (TOTD #186)

  - by arungupta

  TOTD #185 explained how to process text and binary payloads in a WebSocket endpoint. In summary, a text payload may be received as public void receiveTextMessage(String message) {    . . . } And binary payload may be received as: public void recieveBinaryMessage(ByteBuffer message) {    . . .} As you realize, both of these methods receive the text and binary data in raw format. However you may like to receive and send the data using a POJO. This marshaling and unmarshaling can be done in the method implementation but JSR 356 API provides a cleaner way. For encoding and decoding text payload into POJO, Decoder.Text (for inbound payload) and Encoder.Text (for outbound payload) interfaces need to be implemented. A sample implementation below shows how text payload consisting of JSON structures can be encoded and decoded. public class MyMessage implements Decoder.Text<MyMessage>, Encoder.Text<MyMessage> {     private JsonObject jsonObject;    @Override    public MyMessage decode(String string) throws DecodeException {        this.jsonObject = new JsonReader(new StringReader(string)).readObject();               return this;    }     @Override    public boolean willDecode(String string) {        return true;    }     @Override    public String encode(MyMessage myMessage) throws EncodeException {        return myMessage.jsonObject.toString();    } public JsonObject getObject() { return jsonObject; }} In this implementation, the decode method decodes incoming text payload to MyMessage, the encode method encodes MyMessage for the outgoing text payload, and the willDecode method returns true or false if the message can be decoded. The encoder and decoder implementation classes need to be specified in the WebSocket endpoint as: @WebSocketEndpoint(value="/endpoint", encoders={MyMessage.class}, decoders={MyMessage.class}) public class MyEndpoint { public MyMessage receiveMessage(MyMessage message) { . . . } } Notice the updated method signature where the application is working with MyMessage instead of the raw string. Note that the encoder and decoder implementations just illustrate the point and provide no validation or exception handling. Similarly Encooder.Binary and Decoder.Binary interfaces need to be implemented for encoding and decoding binary payload. Here are some references for you: JSR 356: Java API for WebSocket - Specification (Early Draft) and Implementation (already integrated in GlassFish 4 promoted builds) TOTD #183 - Getting Started with WebSocket in GlassFish TOTD #184 - Logging WebSocket Frames using Chrome Developer Tools, Net-internals and Wireshark TOTD #185: Processing Text and Binary (Blob, ArrayBuffer, ArrayBufferView) Payload in WebSocket Subsequent blogs will discuss the following topics (not necessary in that order) ... Error handling Interface-driven WebSocket endpoint Java client API Client and Server configuration Security Subprotocols Extensions Other topics from the API

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• ??????????? - Java SE Embedded 8

  - by kshimizu-Oracle

  Java?OS??????1?????????????????????????????????3?????????????? HEAP: Java????????????????????????????????? NON-HEAP: NON-HEAP????JVM???????????????????Code Cache?Metaspace???2????????????? Code Cache: ????JIT??????????????????????????? Metaspace: HEAP??????????????????????????   JavaVM??????????: VM?????????????????? ??????????????? ????????????????????????????????????????????????????????????????????????? HEAP?Java Mission Control???????????????????? (????)? ????Java SE?????????????API????????????????????????????????????? Mission Control?????API?????????????????????????????????API??????????????? HEAP???????????? VM????????"-Xmx"???????????????? java.lang.Runtime.maxMemory(); ?????HEAP????????? ?????VM????????"-Xms"? ????????????? "-Xms"???????"-Xmx"?????????? java.lang.Runtime.totalMemory(); ???????????HEAP????????????? java.lang.Runtime.freeMemory(); ??NON-HEAP???????????? API??????????? Java Mission Control?????????? ????????????Java Mission Control??????????????????????? ????"NON_HEAP"?????????NON-HEAP?????? ???? HEAP????NON-HEAP?????????????? Java VM???????????????????????????????????????? ?????????????????????????????????? ????HEAP/NON-HEAP?????????????????????????? OS?????????????? Linux???????procfs?Java??????????????????? (VmHWM or VmRSS) ????? ????HEAP/NON-HEAP??????????????????????????? ?????????????????? ??????JVM?????????????????? ?????????????????JVM???????????????????? ???JVM?????? ????????????? Embedded??JVM?????????? ??Embedded???Oracle JVM??????CPU????????????????????????????????????????? ??????CPU??????????????????????????????????????? Minimal/Client/Server??JVM???????????????? ????JVM??????????????????? ??????Compact????????????????? ? 2 - 3?????? Concept Guide (http://docs.oracle.com/javase/8/embedded/embedded-concepts/basic-concepts.htm) ???????? ??JVM??????????? ????????????????????? -Xms: ??????????? ?????????? ?????????????????????????????????????????????????? -Xmx: ??????????? -XX:ReservedCodeCacheSize: Code Cache??????? ?) JIT??????????????Code Cache????????????0???????? -Xint: JIT??????????? ????????????? JIT?????????????????????? ????????????????? -Xss: ???????????????????? ????????????????????????? ????????????????????????????? -XX:CompileThreshold: JIT?????????????????????????????????? ?????????????????????? ????????? ?????????????????? Code Cache?????????? ?????????? ????????????????????? ????????????????????????? ??????????????????????? ?????????????????????

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• best-practices to block social sites

  - by adopilot

  In our company we have around 100 workstation with internet access, And day by day situation getting more worst and worst from perspective of using internet access for the purpose of doing private jobs, and wasting time on social sites. Open hearted I am not for blocking sites like Facebook, Youtube, and others similar but day by day my colleagues do not finishing his tasks and while I looking at their monitor all time they are ruining IE or Mozilla and chat and things like that. In other way Ill like to block youtube sometime when We have very poor internet access speed, Here is my questions: Do other companies blocking social sites ? Do I need dedicated device for that like hardware firewall, super expensive router Or I can do that whit my existing FreeBSD 6.1 self made router with two lan cards and configured nat to act like router. I was trying do that using ipfw and routerfirewall but without success, My code looks like ipfw add 25 deny tcp from 192.168.0.0/20 to www.facebook.com ipfw add 25 deny udp from 192.168.0.0/20 to www.facebook. ipfw add 25 deny tcp from 192.168.0.0/20 to www.dernek. ipfw add 25 deny udp from 192.168.0.0/20 to www.dernek. ipfw add 25 deny tcp from 192.168.0.0/20 to www.youtube. ipfw add 25 deny udp from 192.168.0.0/20 to www.youtube.com

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• Redirect specific domains with DNS

  - by user66377

  Currently we filter internet content using OpenDNS, our internal Windows DC/DNS servers point to the router's DNS, which then points to the OpenDNS servers. This works well to block all computer's on the network equally. New issue. We now need to separate what computers can go to what sites. So facebook is blocked for everyone right now, but I need to open it up to the 3 community computers now. The 3 community computers will be on an untrusted network seperate from the company computers so they can have their own DNS server, from their own router. The issue is though they still must connect to the internet using the same IP address. So OpenDNS sees the same IP and blocks them the same way. We are looking into getting a second IP, but it's not likely an option without going up to the next major level with our ISP which we don't want to do. My thought is this. Can I setup a DNS server on the untrusted network, and then depending on the request that comes in, have it send it to either OpenDNS or our ISP's DNS? Example www.facebook.com and www.youtube.com are both on the OpenDNS blacklist. So if they go to www.youtube.com, the local DNS server goes to the ISP's DNS to get the IP and thus the client gets the right IP and can go to the site. This would be manually entered for each allowed site thus creating a white list. Then if they go to www.facebook.com, since the local DNS server does not find an entry, it sends the request to OpenDNS, which then sees the site is on the blacklist, and thus sends the it's blocked webpage. The local DNS server can be either Bind on Linux or MS DNS on Window 2008. If this can be done, can you give some direction as well as I've never setup a DNS such as this before. Thanks

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• PHP crashing during oAuth scripts

  - by FunkyChicken

  I just installed Nginx 1.2.4 and PHP 5.4.0 (from svn) (php fpm). CentOs 5.8 64 The problem I have is that PHP crashes the moment I run any social oAuth scripts. I have tried to log into Facebook, Twitter and Google with various scripts that I know work on my other servers. When I load the scripts I get a 502 error from Nginx. And I find these errors in the log: in php-fpm log: WARNING: [pool www] child 23821 exited on signal 11 (SIGSEGV) after 1132.862984 seconds from start in nginx log: ERROR: recv() failed (104: Connection reset by peer) while reading response header from upstream From what I can see, it goes wrong when PHP tries to make a request to any of the oAuth servers. https://github.com/mahmudahsan/PHP-SDK-3.0---Graph-API-base-Facebook-Connect-Tutorial-Source for example is one of the scripts that works perfectly on my other machines, but causes PHP to crash. I found: http://stackoverflow.com/questions/3616191/nginx-php-fpm-502-bad-gateway which seems to be a similar problem, but I cannot find a way to solve it. +++ UPDATE +++ Now I have been doing some debugging in 1 of the scripts that is playing up. If you go to line 808 http://pastebin.com/gSnzRtXb it runs the curl_exec() command. When that is ran, it crashes. If i echo'test';exit; just above that line, it echo's correctly, if i do it below that line, php crashes. Which means it's that line 808 which causes the crash. So I made a very simple script to do some testing: http://pastebin.com/Rshnyhcm which also uses curl_exec, but that runs just fine. So I started to dig deeper into that query from the facebook script to see what values the $opts array contains from line 806. Output of that array is: http://pastebin.com/Cq9ffd3R What the problem is, I still have no clue :(

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• Website Use Monitoring for 3 People

  - by linkedlinked

  I work in an IT startup with 2 partners, and I'm the programmer/IT guy -- in other words, the work horse. To make a long story short, I'm doing most of the work right now, while they spend all day on Facebook. That's OK, because they're paying my salary, but if the project fails, I'm sure they'll blame me for it (I'm doing my best to make sure that doesn't happen!), and I want some sort of recourse. I already have an app that blocks time-wasters on my local PC, and keeps logs of when the app is enabled (so I can say "I had Facebook blocked from 9am-5pm today.") Is there any way I can get a brief summary of the most heavily visited sites, split up by client PC? At the end of the month, I want to be able to say "You both load Facebook, on average, every 10 minutes. You spend hours a day on Youtube, and haven't opened up our bugtracker in weeks" and maybe have a nifty chart or graph to match it. We have a crappy D-Link router, and no IT budget. They are both on Windows Vista, I run Ubuntu Linux. I don't want to install any monitoring software on their PC, but I'm totally fine with, say, routing all the network traffic through my machine. I guess I can think of lots of ways to accomplish this (telnet into JSSH and list open tabs? log all the DNS requests, per-domain? even thinking of setting up a webcam on my desk and just keeping 5-minute snapshots...), I just don't really know where to start. Any advice is appreciated, thanks!

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• SBS2011 Standard DNS suddenly not resolving some domains

  - by Matt

  Suddenly today I am unable to resolve common domains like serverfault.com, facebook.com; but other domains like google.com, cnn.com work fine. This is on a client machine (Win7 Pro) connected to an SBS2011 Standard domain. The only DNS server is the SBS2011 server. The same domains work fine on all client PCs I have tried, and the same ones do not work. Using nslookup, I get 'no such domain' errors for facebook.com, and the correct DNS entries for the ones that do work. When I add Google's Public DNS to my client PC as a backup (primary = local SBS server, secondary = 8.8.8.8), everything works fine for my client PC, but querying from the SBS server directly or from other client PCs are broken (so I don't believe it's a firewall issue). My main question is how can I see what servers the SBS2011 server queries if it doesn't know about a domain? There is nothing in our firewall logs that say it blocked any DNS-based packets, but I also wanted to query based on the IP/FQDN on the servers that the SBS server was likely to contact to find out about facebook.com for example. Update 23/05/2012: It appears DNS is working again this morning for the affected websites. Both the DC on its own and all client PCs can once again access the websites that were not loading last night, as well as the websites that were working. I haven't changed anything overnight, so it appears that there was some kind of temporary glitch, but I can't understand what would have caused it on the network.

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• DRY Validation with MVC2

  - by Matthew

  Hi All, I'm trying to figure out how I can define validation rules for my domain objects in one single location within my application but have run in to a snag... Some background: My location has several parts: - Database - DAL - Business Logic Layer - SOAP API Layer - MVC website The MVC website accesses the database via the SOAP API, just as third parties would. We are using server and and client side validation on the MVC website as well as in the SOAP API Layer. To avoid having to manually write client side validation we are implementing strongly typed views in conjunction with the Html.TextBoxFor and Html.ValidationMessageFor HTML helpers, as shown in Step 3 here. We also create custom models for each form where one form takes input for multiple domain objects. This is where the problem begins, the HTML helpers read from the model for the data annotation validation attributes. In most cases our forms deal with multiple domain objects and you can't specify more than one type in the <%@Page ... Inherits="System.Web.Mvc.ViewPage" % page directive. So we are forced to create a custom model class, which would mean duplicating validation attributes from the domain objects on to the model class. I've spent quite some time looking for workarounds to this, such has referencing the same MetadataType from both the domain class and the custom MVC models, but that won't work for several reasons: You can only specify one MetadataType attribute per class, so its a problem if a model references multiple domain objects, each with their own metadata type. The data annotation validation code throws an exception if the model class doesn't contain a property that is specified in the referenced MetadataType which is a problem with the model only deals with a subset of the properties for a given domain object. I've looked at other solutions as well but to no avail. If anyone has any ideas on how to achieve a single source for validation logic that would work across MVC client and server side validation functionality and other locations (such as my SOAP API) I would love to hear it! Thanks in advance, Matthew

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• In Asp.Net MVC 2 is there a better way to return 401 status codes without getting an auth redirect

  - by Greg Roberts

  I have a portion of my site that has a lightweight xml/json REST API. Most of my site is behind forms auth but only some of my API actions require authentication. I have a custom AuthorizeAttribute for my API that I use to check for certain permissions and when it fails it results in a 401. All is good, except since I'm using forms auth, Asp.net conveniently converts that into a 302 redirect to my login page. I've seen some previous questions that seem a bit hackish to either return a 403 instead or to put some logic in the global.asax protected void Application_EndRequest() that will essentially convert 302 to 401 where it meets whatever criteria. Previous Question Previous Question 2 What I'm doing now is sort of like one of the questions, but instead of checking the Application_EndRequest() for a 302 I make my authorize attribute return 666 which indicates to me that I need to set this to a 401. Here is my code: protected void Application_EndRequest() { if (Context.Response.StatusCode == MyAuthAttribute.AUTHORIZATION_FAILED_STATUS) { //check for 666 - status code of hidden 401 Context.Response.StatusCode = 401; } } Even though this works, my question is there something in Asp.net MVC 2 that would prevent me from having to do this? Or, in general is there a better way? I would think this would come up a lot for anyone doing REST api's or just people that do ajax requests in their controllers. The last thing you want is to do a request and get the content of a login page instead of json.

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• Synchronizing Asynchronous request handlers in Silverlight environment

  - by Eric Lifka

  For our senior design project my group is making a Silverlight application that utilizes graph theory concepts and stores the data in a database on the back end. We have a situation where we add a link between two nodes in the graph and upon doing so we run analysis to re-categorize our clusters of nodes. The problem is that this re-categorization is quite complex and involves multiple queries and updates to the database so if multiple instances of it run at once it quickly garbles data and breaks (by trying to re-insert already used primary keys). Essentially it's not thread safe, and we're trying to make it safe, and that's where we're failing and need help :). The create link function looks like this: private Semaphore dblock = new Semaphore(1, 1); // This function is on our service reference and gets called // by the client code. public int addNeed(int nodeOne, int nodeTwo) { dblock.WaitOne(); submitNewNeed(createNewNeed(nodeOne, nodeTwo)); verifyClusters(nodeOne, nodeTwo); dblock.Release(); return 0; } private void verifyClusters(int nodeOne, int nodeTwo) { // Run analysis of nodeOne and nodeTwo in graph } All copies of addNeed should wait for the first one that comes in to finish before another can execute. But instead they all seem to be running and conflicting with each other in the verifyClusters method. One solution would be to force our front end calls to be made synchronously. And in fact, when we do that everything works fine, so the code logic isn't broken. But when it's launched our application will be deployed within a business setting and used by internal IT staff (or at least that's the plan) so we'll have the same problem. We can't force all clients to submit data at different times, so we really need to get it synchronized on the back end. Thanks for any help you can give, I'd be glad to supply any additional information that you could need!

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• Getting Response from TIdHttp with Error Code 400

  - by Robert Love

  I have been writing a Delphi library for StackApps API. I have run into a problem with Indy. I am using the version that ships with Delphi 2010. If you pass invalid parameters to one of the StackApps API it will return a HTTP Error Code 400 and then in the response it will contain a JSON object with more details. By visiting http://api.stackoverflow.com/0.8/stats/?Key=BadOnPurpose in Chrome Browser you can see an Example. I.E. and Firefox hide the JSON. Using WireShark I can see that the JSON object is returned using the code below, but I am unable to access it using Indy. For this test code I dropped a TIdHttp component on the form and placed the following code in a button click. procedure TForm10.Button2Click(Sender: TObject); var SS : TStringStream; begin SS := TStringStream.Create; IdHTTP1.Get('http://api.stackoverflow.com/0.8/stats/?Key=BadOnPurpose',SS,[400]); Memo1.Lines.Text := SS.DataString; SS.Free; end; I passed [400] so that it would not raise the 400 exception. It is as if Indy stopped reading the response. As the contents of Memo1 are empty. I am looking for a way to get the JSON Details.

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• EJB3 JNDI Lookup Failure in JEE application client

  - by Hank

  I'm trying to access an EJB3 from a JEE client-application, but keep getting nothing but lookup failures. My JEE Application 'CoreServer' is exposing a number of beans with remote interfaces. I have no problem accessing them from a Web Application deployed on the same Glassfish v3.0.1. Now I'm trying to access it from a client-application: public class Main { public static void main(String[] args) { CampaignControllerRemote bean = null; try { InitialContext ctx = new InitialContext(); bean = (CampaignControllerRemote) ctx.lookup("java:global/CoreServer/CampaignController"); } catch (Exception e) { System.out.println(e.getMessage()); } if (bean != null) { Campaign campaign = bean.get(361); if (campaign != null) { System.out.println("Got "+ campaign); } } } } When I run deploy it to Glassfish and run it from the appclient, I get this error: Lookup failed for 'java:global/CoreServer/CampaignController' in SerialContext targetHost=localhost,targetPort=3700,orb'sInitialHost=localhost,orb'sInitialPort=3700 However, that's exactly the same JNDI-name I use when I lookup the bean from the WebApplication (via SessionContext, not InitialContext - does that matter?). Also, when I deploy 'CoreServer', Glassfish reports: Portable JNDI names for EJB CampaignController : [java:global/CoreServer/CampaignController!mvs.api.CampaignControllerRemote, java:global/CoreServer/CampaignController] Glassfish-specific (Non-portable) JNDI names for EJB CampaignController : [mvs.api.CampaignControllerRemote, mvs.api.CampaignControllerRemote#mvs.api.CampaignControllerRemote] I tried all four names, none worked. Is the appclient unable to access beans with (only) Remote interfaces?

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• How to upload images from iPhone app developed using Titanium

  - by Karthik.K

  Hi, I finally landed up in developing an iPhone app using Titanium Mobile. Now the problem I face is, Im able to run the app, and the app also sends the image to the server. But Im not able to see the file that got uploaded to the server. I have pasted the iPhone app's code to send image to the server and also, the PHP file that would receive the file from the app. var win = Titanium.UI.currentWindow; var ind=Titanium.UI.createProgressBar({ width:200, height:50, min:0, max:1, value:0, style:Titanium.UI.iPhone.ProgressBarStyle.PLAIN, top:10, message:'Uploading Image', font:{fontSize:12, fontWeight:'bold'}, color:'#888' }); win.add(ind); ind.show(); Titanium.Media.openPhotoGallery({ success:function(event) { Ti.API.info("success! event: " + JSON.stringify(event)); var image = event.media; var xhr = Titanium.Network.createHTTPClient(); xhr.onerror = function(e) { Ti.API.info('IN ERROR ' + e.error); }; xhr.onload = function() { Ti.API.info('IN ONLOAD ' + this.status + ' readyState ' + this.readyState); }; xhr.onsendstream = function(e) { ind.value = e.progress ; Ti.API.info('ONSENDSTREAM - PROGRESS: ' + e.progress+' '+this.status+' '+this.readyState); }; // open the client xhr.open('POST','http://www.myserver.com/tmp/upload2.php'); xhr.setRequestHeader("Connection", "close"); // send the data xhr.send({media:image}); }, cancel:function() { }, error:function(error) { }, allowImageEditing:true }); And here is the PHP code on the server: http://www.pastie.org/891050 I'm not sure where I'm going wrong. Please help me out in this issue. Would love to provide if you need some more information.

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• Java Appengine APPSTATS causing java out of memory error

  - by aloo

  I have several servlets in my java appengine app that do in memory sorting and take on the order of seconds to complete. These complete error free. However, I recently enabled appstats for appengine and started receiving the following error: java.lang.OutOfMemoryError: Java heap space at java.util.Arrays.copyOf(Unknown Source) at java.lang.AbstractStringBuilder.expandCapacity(Unknown Source) at java.lang.AbstractStringBuilder.append(Unknown Source) at java.lang.StringBuilder.append(Unknown Source) at java.lang.StringBuilder.append(Unknown Source) at java.lang.StringBuilder.append(Unknown Source) at com.google.appengine.repackaged.com.google.protobuf.TextFormat$TextGenerator.write(TextFormat.java:344) at com.google.appengine.repackaged.com.google.protobuf.TextFormat$TextGenerator.print(TextFormat.java:332) at com.google.appengine.repackaged.com.google.protobuf.TextFormat.printUnknownFields(TextFormat.java:249) at com.google.appengine.repackaged.com.google.protobuf.TextFormat.print(TextFormat.java:47) at com.google.appengine.repackaged.com.google.protobuf.TextFormat.printToString(TextFormat.java:73) at com.google.appengine.tools.appstats.Recorder.makeSummary(Recorder.java:157) at com.google.appengine.tools.appstats.Recorder.makeSyncCall(Recorder.java:239) at com.google.apphosting.api.ApiProxy.makeSyncCall(ApiProxy.java:98) at com.google.appengine.api.datastore.DatastoreApiHelper.makeSyncCall(DatastoreApiHelper.java:54) at com.google.appengine.api.datastore.PreparedQueryImpl.runQuery(PreparedQueryImpl.java:127) at com.google.appengine.api.datastore.PreparedQueryImpl.asQueryResultList(PreparedQueryImpl.java:81) at org.datanucleus.store.appengine.query.DatastoreQuery.fulfillEntityQuery(DatastoreQuery.java:379) at org.datanucleus.store.appengine.query.DatastoreQuery.executeQuery(DatastoreQuery.java:289) at org.datanucleus.store.appengine.query.DatastoreQuery.performExecute(DatastoreQuery.java:239) at org.datanucleus.store.appengine.query.JDOQLQuery.performExecute(JDOQLQuery.java:89) at org.datanucleus.store.query.Query.executeQuery(Query.java:1489) at org.datanucleus.store.query.Query.executeWithArray(Query.java:1371) at org.datanucleus.jdo.JDOQuery.execute(JDOQuery.java:243) at com.poo.pooserver.dataaccess.DataAccessHelper.getPooStream(DataAccessHelper.java:204) at com.poo.pooserver.GetPooStreamServlet.doPost(GetPooStreamServlet.java:58) at javax.servlet.http.HttpServlet.service(HttpServlet.java:713) at javax.servlet.http.HttpServlet.service(HttpServlet.java:806) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166) at com.google.appengine.tools.appstats.AppstatsFilter.doFilter(AppstatsFilter.java:92) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)

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• Using section header in Sendgrid

  - by Zefiryn

  I am trying to send emails through sendgrid in Zend application. I copy the php code from the sendgrid documentation (smtapi class and swift). I create a template with places that should be substituted with %variable%. Now I create headers for sendgrid as defined here: http://docs.sendgrid.com/documentation/api/smtp-api/developers-guide/ In result I get something looking like this: { "to": ["[email protected]", "[email protected]", "[email protected]", "[email protected]", "[email protected]"], "sub": {"%firstname%": ["Benny", "Chaim", "Ephraim", "Yehuda", "will"]}, "section": {"%postername%": "Rabbi Yitzchak Lieblich", "%postermail%": "[email protected]", "%categoryname%": "General", "%threadname%": "Completely new thread", "%post%": "This thread is to inform you about something very important", "%threadurl%": "http:\/\/hb.local\/forums\/general\/thread\/143", "%replyto%": "http:\/\/hb.local\/forums\/general\/thread\/143", "%unsubscribeurl%": "http:\/\/hb.local\/forums\/settings\/", "%subscribeurl%": "http:\/\/hb.local\/forums\/subscribe-thread\/id\/143\/token\/1b20eb7799829e22ba2d48ca0867d3ce"} } Now while all data defined in "sub" changes I cannot make section work. In the final email I still got %postername%. When I move this data to sub and repeat them for each email everything is working fine. Has anyone a clue what I am doing wrong? Docs for section are here: http://docs.sendgrid.com/documentation/api/smtp-api/developers-guide/section-tags/

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• Remove duplicates from a list of nested dictionaries

  - by user2924306

  I'm writing my first python program to manage users in Atlassian On Demand using their RESTful API. I call the users/search?username= API to retrieve lists of users, which returns JSON. The results is a list of complex dictionary types that look something like this: [ { "self": "http://www.example.com/jira/rest/api/2/user?username=fred", "name": "fred", "avatarUrls": { "24x24": "http://www.example.com/jira/secure/useravatar?size=small&ownerId=fred", "16x16": "http://www.example.com/jira/secure/useravatar?size=xsmall&ownerId=fred", "32x32": "http://www.example.com/jira/secure/useravatar?size=medium&ownerId=fred", "48x48": "http://www.example.com/jira/secure/useravatar?size=large&ownerId=fred" }, "displayName": "Fred F. User", "active": false }, { "self": "http://www.example.com/jira/rest/api/2/user?username=andrew", "name": "andrew", "avatarUrls": { "24x24": "http://www.example.com/jira/secure/useravatar?size=small&ownerId=andrew", "16x16": "http://www.example.com/jira/secure/useravatar?size=xsmall&ownerId=andrew", "32x32": "http://www.example.com/jira/secure/useravatar?size=medium&ownerId=andrew", "48x48": "http://www.example.com/jira/secure/useravatar?size=large&ownerId=andrew" }, "displayName": "Andrew Anderson", "active": false } ] I'm calling this multiple times and thus getting duplicate people in my results. I have been searching and reading but cannot figure out how to deduplicate this list. I figured out how to sort this list using a lambda function. I realize I could sort the list, then iterate and delete duplicates. I'm thinking there must be a more elegant solution. Thank you!

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• RESTful WCF Data Service Authentication

  - by Adrian Grigore

  Hi, I'd like to implement a REST api to an existing ASP.NET MVC website. I've managed to set up WCF Data services so that I can browse my data, but now the question is how to handle authentication. Right now the data service is secured via the site's built in forms authentication, and that's ok when accessing the service from AJAX forms. However, It's not ideal for a RESTful api. What I would like as an alternative to forms authentication is for the users to simply embed the user name and password into the url to the web service or as request parameters. For example, if my web service is usually accessible as http://localhost:1234/api.svc I'd like to be able to access it using the url http://localhost:1234/api.svc/{login}/{password} So, my questions are as follows: Is this a sane approach? If yes, how can I implement this? It seems trivial redirecting GET requests so that the login and password are attached as GET parameters. I also know how to inspect the http context and use those parameters to filter the results. But I am not sure if / how the same approach could be applied to POST, PUT and DELETE requests. Thanks, Adrian

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• Blackberry how to display message in app if device got no internet connection?

  - by Johannes

  Hello I've just started with programming for the Blackberry device. I'm using version 5 of the API. I'm building a very simple application which is just a browserfield. So far it's all working great. I can display my browserfield with the content I need. The problem I'm having now is if the device doesn't have an active internet connection I get the ugly "Error requesting content for" message. I would need to someone display my own message if the device doesn't have an active connection. Something like "You need to have an active internet connection to use this application" with an Exit button which closes the app. I've tried to find this for hours but no luck. Hopefully it's something relatively easy so I can get help here. Here's my code so far: package com.mycompany.webview; import net.rim.device.api.browser.field2.*; import net.rim.device.api.ui.*; import net.rim.device.api.ui.container.*; public class webview extends UiApplication { public static void main(String[] args) { webview app = new webview(); app.enterEventDispatcher(); } public webview() { pushScreen(new webviewScreen()); } } class webviewScreen extends MainScreen { public webviewScreen() { BrowserField myBrowserField = new BrowserField(); add(myBrowserField); myBrowserField.requestContent("http://www.google.com"); } } Would really appreciate some help please. Thanks

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• Using Traveling Salesman Solver to Decide Hamiltonian Path

  - by Firas Assaad

  This is for a project where I'm asked to implement a heuristic for the traveling salesman optimization problem and also the Hamiltonian path or cycle decision problem. I don't need help with the implementation itself, but have a question on the direction I'm going in. I already have a TSP heuristic based on a genetic algorithm: it assumes a complete graph, starts with a set of random solutions as a population, and works to improve the population for a number of generations. Can I also use it to solve the Hamiltonian path or cycle problems? Instead of optimizing to get the shortest path, I just want to check if there is a path. Now any complete graph will have a Hamiltonian path in it, so the TSP heuristic would have to be extended to any graph. This could be done by setting the edges to some infinity value if there is no path between two cities, and returning the first path that is a valid Hamiltonian path. Is that the right way to approach it? Or should I use a different heuristic for Hamiltonian path? My main concern is whether it's a viable approach since I can be somewhat sure that TSP optimization works (because you start with solutions and improve them) but not if a Hamiltonian path decider would find any path in a fixed number of generations. I assume the best approach would be to test it myself, but I'm constrained by time and thought I'd ask before going down this route... (I could find a different heuristic for Hamiltonian path instead)

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