Search Results

Search found 2074 results on 83 pages for 'arbitrary precision'.

Page 72/83 | < Previous Page | 68 69 70 71 72 73 74 75 76 77 78 79  | Next Page >

• Managing server instance identity on EC2

  - by kikibobo

  I recently brought up a cluster on EC2, and I felt like I had to invent a lot of things. I'm wondering what kinds of tools, patterns, ideas are out there for how to deal with this. Some context: I had 3 different kinds of servers, so first I created AMIs for each of them. The first AMI had zookeeper, so step one in deploying the system was to get the zookeeper server running. My script then made a note of the mapping between EC2's completely arbitrary and unpredictable hostnames, and the zookeeper server. Then as I brought up new instances of the other 2 kinds of servers, the first thing I would do is ssh to the new server, and add the zookeeper server to its /etc/hosts file. Then as the server software on each instance starts up, it can find zookeeper. Obviously this is a problem that lots of people have to solve, and it probably works a little bit differently in different clouds. Are there products that address this concept? I was pretty surprised that EC2 didn't provide some kind of way to tie your own name to its name. Thanks for any ideas.

  Read the article

• Full and Partial Matching of Sets

  - by jeffrey

  I have several sets of the same type [Y, M, D] and am trying to write a function to search these sets and return an array of the available sets that fit my parameters. ReturnedSets = return_matches(Y,M,D); I want the three parameters of the function return_matches to be optional. Which means any combination of values can be used to return the sets. For example, one could write - return_matches(13,null,2); - and the function would look for all sets that contain [13, anyValue, 2]; I'm writing this in PHP, to allow users to manage dated files on my website, but I'd like to be able to use this function again for other uses. Thanks! edit: (This, or variations of this, is all I can come up with so far... There is something extra that I don't understand, because this function ends up / would not work to return sets that contain y and d, but leaving m arbitrary. if(y == s[0]){ if(m == s[1]){ if(d == s[2]){ print "day match"; } } else {print "month match";} } else {print "year match";} } else {print "no match";}

  Read the article

• Looping through a method without for/foreach/while

  - by RichK

  Is there a way of calling a method/lines of code multiple times not using a for/foreach/while loop? For example, if I were to use to for loop: int numberOfIterations = 6; for(int i = 0; i < numberOfIterations; i++) { DoSomething(); SomeProperty = true; } The lines of code I'm calling don't use 'i' and in my opinion the whole loop declaration hides what I'm trying to do. This is the same for a foreach. I was wondering if there's a looping statement I can use that looks something like: do(6) { DoSomething(); SomeProperty = true; } It's really clear that I just want to execute that code 6 times and there's no noise involving index instantiating and adding 1 to some arbitrary variable. As a learning exercise I have written a static class and method: Do.Multiple(int iterations, Action action) Which works but scores very highly on the pretentious scale and I'm sure my peers wouldn't approve. I'm probably just being picky and a for loop is certainly the most recognisable, but as a learning point I was just wondering if there (cleaner) alternatives. Thanks. (I've had a look at this thread, but it's not quite the same) http://stackoverflow.com/questions/2248985/using-ienumerable-without-foreach-loop

  Read the article

• why does django-registration use an "activation window" for activating accounts?

  - by bharal

  i'm using django-registration, which is a django lib that helps with users registering on a django-built website. All well and dandy, except that it insists i have an "activation email" associated with all new users. It defaults to a 7 day window, after which, if someone signed up (and we then sent an email to confirm their email address) but didn't click on the link in the sent email within the 7 days, then they cannot sign up. Instead, they need to do the whole process all over again. I'm sure this is a concept that exists generally in web design, because why would django-registration make its own arbitrary signup process up? Anyway, the question is why? What do i gain by having the peace of mind knowing that all the users of my site are the kind of go-getters that click on registration emails with 7 days of receiving them? Why should i sleep easier knowing that my database isn't filled with users who, for whatever reason, clicked through to sign up but didn't actually want to sign up? cheers!

  Read the article

• C# properties: How are they instantiated?

  - by Pedery

  Hi! This might be a pretty straightforward question, but I'm trying to understand some of the internal workings of the compilation. Very simply put, imagine an arbitrary object being instantiated. This object is then allocated on the heap. The object has a property of type PointF (which is value type), with a get and a set method. Imagine the get and the set method containing a few calculations for doing their work. How and where (stack/heap) and when is this code instantiated? This is the background for this question: I'm writing get and set methods for an object and these methods need to be accessed very frequently. The get and set code in itself is rather massive so I feared that in a worst case scenario the methods would be instantiated as an object or a value type with all internal code for every access of the property. On the other hand the code is probably instantiated when the main object is created and the CPU is simply told to jmp to the property code start. Anyway, this is what I want to have clarified.

  Read the article

• A good way to write unit tests

  - by bobobobo

  So, I previously wasn't really in the practice of writing unit tests - now I kind of am and I need to check if I'm on the right track. Say you have a class that deals with math computations. class Vector3 { public: // Yes, public. float x,y,z ; // ... ctors ... } ; Vector3 operator+( const Vector3& a, const Vector3 &b ) { return Vector3( a.x + b.y /* oops!! hence the need for unit testing.. */, a.y + b.y, a.z + b.z ) ; } There are 2 ways I can really think of to do a unit test on a Vector class: 1) Hand-solve some problems, then hard code the numbers into the unit test and pass only if equal to your hand and hard-coded result bool UnitTest_ClassVector3_operatorPlus() { Vector3 a( 2, 3, 4 ) ; Vector3 b( 5, 6, 7 ) ; Vector3 result = a + b ; // "expected" is computed outside of computer, and // hard coded here. For more complicated operations like // arbitrary axis rotation this takes a bit of paperwork, // but only the final result will ever be entered here. Vector3 expected( 7, 9, 11 ) ; if( result.isNear( expected ) ) return PASS ; else return FAIL ; } 2) Rewrite the computation code very carefully inside the unit test. bool UnitTest_ClassVector3_operatorPlus() { Vector3 a( 2, 3, 4 ) ; Vector3 b( 5, 6, 7 ) ; Vector3 result = a + b ; // "expected" is computed HERE. This // means all you've done is coded the // same thing twice, hopefully not having // repeated the same mistake again Vector3 expected( 2 + 5, 6 + 3, 4 + 7 ) ; if( result.isNear( expected ) ) return PASS ; else return FAIL ; } Or is there another way to do something like this?

  Read the article

• Permuting output of a tree of closures

  - by yan

  This a conceptual question on how one would implement the following in Lisp (assuming Common Lisp in my case, but any dialect would work). Assume you have a function that creates closures that sequentially iterate over an arbitrary collection (or otherwise return different values) of data and returns nil when exhausted, i.e. (defun make-counter (up-to) (let ((cnt 0)) (lambda () (if (< cnt up-to) (incf cnt) nil)))) CL-USER> (defvar gen (make-counter 3)) GEN CL-USER> (funcall gen) 1 CL-USER> (funcall gen) 2 CL-USER> (funcall gen) 3 CL-USER> (funcall gen) NIL CL-USER> (funcall gen) NIL Now, assume you are trying to permute a combinations of one or more of these closures. How would you implement a function that returns a new closure that subsequently creates a permutation of all closures contained within it? i.e.: (defun permute-closures (counters) ......) such that the following holds true: CL-USER> (defvar collection (permute-closures (list (make-counter 3) (make-counter 3)))) CL-USER> (funcall collection) (1 1) CL-USER> (funcall collection) (1 2) CL-USER> (funcall collection) (1 3) CL-USER> (funcall collection) (2 1) ... and so on. The way I had it designed originally was to add a 'pause' parameter to the initial counting lambda such that when iterating you can still call it and receive the old cached value if passed ":pause t", in hopes of making the permutation slightly cleaner. Also, while the example above is a simple list of two identical closures, the list can be an arbitrarily-complicated tree (which can be permuted in depth-first order, and the resulting permutation set would have the shape of the tree.). I had this implemented, but my solution wasn't very clean and am trying to poll how others would approach the problem. Thanks in advance.

  Read the article

• Optimize Duplicate Detection

  - by Dave Jarvis

  Background This is an optimization problem. Oracle Forms XML files have elements such as: <Trigger TriggerName="name" TriggerText="SELECT * FROM DUAL" ... /> Where the TriggerText is arbitrary SQL code. Each SQL statement has been extracted into uniquely named files such as: sql/module=DIAL_ACCESS+trigger=KEY-LISTVAL+filename=d_access.fmb.sql sql/module=REP_PAT_SEEN+trigger=KEY-LISTVAL+filename=rep_pat_seen.fmb.sql I wrote a script to generate a list of exact duplicates using a brute force approach. Problem There are 37,497 files to compare against each other; it takes 8 minutes to compare one file against all the others. Logically, if A = B and A = C, then there is no need to check if B = C. So the problem is: how do you eliminate the redundant comparisons? The script will complete in approximately 208 days. Script Source Code The comparison script is as follows: #!/bin/bash echo Loading directory ... for i in $(find sql/ -type f -name \*.sql); do echo Comparing $i ... for j in $(find sql/ -type f -name \*.sql); do if [ "$i" = "$j" ]; then continue; fi # Case insensitive compare, ignore spaces diff -IEbwBaq $i $j > /dev/null # 0 = no difference (i.e., duplicate code) if [ $? = 0 ]; then echo $i :: $j >> clones.txt fi done done Question How would you optimize the script so that checking for cloned code is a few orders of magnitude faster? System Constraints Using a quad-core CPU with an SSD; trying to avoid using cloud services if possible. The system is a Windows-based machine with Cygwin installed -- algorithms or solutions in other languages are welcome. Thank you!

  Read the article

• C# assign values of array to separate variables in one line

  - by Sarah Vessels

  Can I assign each value in an array to separate variables in one line in C#? Here's an example in Ruby code of what I want: irb(main):001:0> str1, str2 = ["hey", "now"] => ["hey", "now"] irb(main):002:0> str1 => "hey" irb(main):003:0> str2 => "now" I'm not sure if what I'm wanting is possible in C#. Edit: for those suggesting I just assign the strings "hey" and "now" to variables, that's not what I want. Imagine the following: irb(main):004:0> val1, val2 = get_two_values() => ["hey", "now"] irb(main):005:0> val1 => "hey" irb(main):006:0> val2 => "now" Now the fact that the method get_two_values returned strings "hey" and "now" is arbitrary. In fact it could return any two values, they don't even have to be strings.

  Read the article

• How to queue and call actual methods (rather than immediately eval) in java?

  - by alleywayjack

  There are a list of tasks that are time sensitive (but "time" in this case is arbitrary to what another program tells me - it's more like "ticks" rather than time). However, I do NOT want said methods to evaluate immediately. I want one to execute after the other finished. I'm using a linked list for my queue, but I'm not really sure how/if I can access the actual methods in a class without evaluating them immediate. The code would look something like... LinkedList<Method> l = new LinkedList<Method>(); l.add( this.move(4) ); l.add( this.read() ); l.removeFirst().call(); //wait 80 ticks l.removeFirst().call(); move(4) would execute immediately, then 80 ticks later, I would remove it from the list and call this.read() which would then be executed. I'm assuming this has to do with the reflection classes, and I've poked around a bit, but I can't seem to get anything to work, or do what I want. If only I could use pointers...

  Read the article

• Trouble getting QMainWindow to scroll

  - by random

  A minimal example: class MainWindow(QtGui.QMainWindow): def __init__(self, parent = None): QtGui.QMainWindow.__init__(self, parent) winWidth = 683 winHeight = 784 screen = QtGui.QDesktopWidget().availableGeometry() screenCenterX = (screen.width() - winWidth) / 2 screenCenterY = (screen.height() - winHeight) / 2 self.setGeometry(screenCenterX, screenCenterY, winWidth, winHeight) layout = QtGui.QVBoxLayout() layout.addWidget(FormA()) mainWidget = QtGui.QWidget() mainWidget.setLayout(layout) self.setCentralWidget(mainWidget) FormA is a QFrame with a VBoxLayout that can expand to an arbitrary number of entries. In the code posted above, if the entries in the forms can't fit in the window then the window itself grows. I'd prefer for the window to become scrollable. I've also tried the following... replacing mainWidget = QtGui.QWidget() mainWidget.setLayout(layout) self.setCentralWidget(mainWidget) with mainWidget = QtGui.QScrollArea() mainWidget.setLayout(layout) self.setCentralWidget(mainWidget) results in the forms and entries shrinking if they can't fit in the window. Replacing it with mainWidget = QtGui.QWidget() mainWidget.setLayout(layout) scrollWidget = QtGui.QScrollArea() scrollWidget.setWidget(mainWidget) self.setCentralWidget(scrollWidget) results in the mainwidget (composed of the forms) being scrunched in the top left corner of the window, leaving large blank areas on the right and bottom of it, and still isn't scrollable. I can't set a limit on the size of the window because I wish for it to be resizable. How can I make this window scrollable?

  Read the article

• C# Generic Generics (A Serious Question)

  - by tahirhassan

  In C# I am trying to write code where I would be creating a Func delegate which is in itself generic. For example the following (non-Generic) delegate is returning an arbitrary string: Func<string> getString = () => "Hello!"; I on the other hand want to create a generic which acts similarly to generic methods. For example if I want a generic Func to return default(T) for a type T. I would imagine that I write code as follows: Func<T><T> getDefaultObject = <T>() => default(T); Then I would use it as getDefaultObject<string>() which would return null and if I were to write getDefaultObject<int>() would return 0. This question is not merely an academic excercise. I have found numerous places where I could have used this but I cannot get the syntax right. Is this possible? Are there any libraries which provide this sort of functionality?

  Read the article

• Boolean comparison of array of strings in Ruby

  - by Kyle Kaitan

  I've got an array in Ruby that essentially represents a square boolean matrix. Dots represent zeroes, while any other character represents ones. Example: irb(main):044:0> g => [".b", "m."] # This grid has two '1' values and two '0' values. I'd like to perform a specified logical operation (say, OR) on this array with another similar array to get a third result. For example, if h is ["q.", "r."], then something akin to g.perform_or(h) should yield a new array ["qb", "r."]. (The choice of r to represent the result of 'm' || 'r' is arbitrary and not relevant; any other non-'.' character can be there.) How might I do this? Edit: I made an error in my example. Apologies!

  Read the article

• Java: Efficient Equivalent to Removing while Iterating a Collection

  - by Claudiu

  Hello everyone. We all know you can't do this: for (Object i : l) if (condition(i)) l.remove(i); ConcurrentModificationException etc... this apparently works sometimes, but not always. Here's some specific code: public static void main(String[] args) { Collection<Integer> l = new ArrayList<Integer>(); for (int i=0; i < 10; ++i) { l.add(new Integer(4)); l.add(new Integer(5)); l.add(new Integer(6)); } for (Integer i : l) { if (i.intValue() == 5) l.remove(i); } System.out.println(l); } This, of course, results in: Exception in thread "main" java.util.ConcurrentModificationException ...even though multiple threads aren't doing it... Anyway. What's the best solution to this problem? "Best" here means most time and space efficient (I realize you can't always have both!) I'm also using an arbitrary Collection here, not necessarily an ArrayList, so you can't rely on get.

  Read the article

• Conceptual data modeling: Is RDF the right tool? Other solutions?

  - by paprika

  I'm planning a system that combines various data sources and lets users do simple queries on these. A part of the system needs to act as an abstraction layer that knows all connected data sources: the user shouldn't [need to] know about the underlying data "providers". A data provider could be anything: a relational DBMS, a bug tracking system, ..., a weather station. They are hooked up to the query system through a common API that defines how to "offer" data. The type of queries a certain data provider understands is given by its "offer" (e.g. I know these entities, I can give you aggregates of type X for relationship Y, ...). My concern right now is the unification of the data: the various data providers need to agree on a common vocabulary (e.g. the name of the entity "customer" could vary across different systems). Thus, defining a high level representation of the entities and their relationships is required. So far I have the following requirements: I need to be able to define objects and their properties/attributes. Further, arbitrary relations between these objects need to be represented: a verb that defines the nature of the relation (e.g. "knows"), the multiplicity (e.g. 1:n) and the direction/navigability of the relation. It occurs to me that RDF is a viable option, but is it "the right tool" for this job? What other solutions/frameworks do exist for semantic data modeling that have a machine readable representation and why are they better suited for this task? I'm grateful for every opinion and pointer to helpful resources.

  Read the article

• How to structure Javascript programs in complex web applications?

  - by mixedpickles

  Hi there. I have a problem, which is not easily described. I'm writing a web application that makes heavy usage of jquery and ajax calls. Now I don't have experience in designing the architecture for javascript programms, but I realize that my program has not a good structure. I think I have to many identifiers referring to the same (at least more or less) thing. Let's have an exemplary look at an arbitrary UI widget: The eventhandlers use DOM elements as parameters. The DOM element represents a widget in the browser. A lot of times I use jQuery objects (I think they are basically a wrapper around DOM elements) to do something with the widget. Sometimes they are used transiently, sometimes they are stored in a variable for later purposes. The ajax function calls use strings identifiers for these widgets. They are processed server side. Beside that I have a widget class whose instances represents a widget. It is instantiated through the new operator. Now I have somehow four different object identifiers for the same thing, which needs to be kept in sync until the page is loaded anew. This seems not to be a good thing. Any advice?

  Read the article

• Prevent cached objects to end up in the database with Entity Framework

  - by Dirk Boer

  We have an ASP.NET project with Entity Framework and SQL Azure. A big part of our data only needs to be updated a few times a day, other data is very volatile. The data that barely changes we cache in memory at startup, detach from the context and than use it mainly for reading, drastically lowering the amount of database requests we have to do. The volatile data is requested everytime by a DbContext per Http request. When we do an update to the cached data, we send a message to all instances to catch a fresh version of all the data from the SQL server. So far, so good. Until we introduced a bug that linked one of these 'cached' objects to the 'volatile' data, and did a SaveChanges. Well, that was quite a mess. The whole data tree was added again and again by every update, corrupting the whole database with a whole lot of duplicated data. As a complete hack I added a completely arbitrary column with a UniqueConstraint and some gibberish data on one of the root tables; hopefully failing the SaveChanges() next time we introduce such a bug because it will violate the Unique Constraint. But it is of course hacky, and I'm still pretty scared ;P Are there any better ways to prevent whole tree's of cached objects ending up in the database? More information Project is ASP.NET MVC I cache this data, because it is mainly read only, and this saves a tons of extra database calls per http request

  Read the article

• CSS 100% height with padding/margin

  - by Toji

  This has been driving me crazy for a couple of days now, but in reality it's a problem that I've hit off and on for the last few years: With HTML/CSS how can I make an element that has a width and/or height that is 100% of it's parent element and still has proper padding or margins? By "proper" I mean that if my parent element is 200px tall and I specify 100% height with 5px padding I would expect that I should get a 190px high element with 5px "border" on all sides, nicely centered in the parent element. Now, I know that that's not how the standard box model specifies it should work (although I'd like to know why, exactly...), so the obvious answer doesn't work: #myDiv { width: 100% height: 100%; padding: 5px; } But it would seem to me that there must be SOME way of reliably producing this effect for a parent of arbitrary size. Does anyone know of a way of accomplishing this (seemingly simple) task? Oh, and for the record I'm not terribly interested in IE compatibility so that should (hopefully) make things a bit easier. EDIT: Since an example was asked for, here's the simplest one I can think of: <html style="height: 100%"> <body style="height: 100%"> <div style="background-color: black; height: 100%; padding: 25px"></div> </body> </html> The challenge is then to get the black box to show up with a 25 pixel padding on all edges without the page growing big enough to require scrollbars.

  Read the article

• Migrate from MySQL to PostgreSQL on Linux (Kubuntu)

  - by Dave Jarvis

  Storyline Trying to migrate a database from MySQL to PostgreSQL. All the documentation I have read covers, in great detail, how to migrate the structure. I have found very little documentation on migrating the data. The schema has 13 tables (which have been migrated successfully) and 9 GB of data. MySQL version: 5.1.x PostgreSQL version: 8.4.x I want to use the R programming language to analyze the data using SQL select statements; PostgreSQL has PL/R, but MySQL has nothing (as far as I can tell). A long time ago in a galaxy far, far away... Create the database location (/var has insufficient space; also dislike having the PostgreSQL version number everywhere -- upgrading would break scripts!): sudo mkdir -p /home/postgres/main sudo cp -Rp /var/lib/postgresql/8.4/main /home/postgres sudo chown -R postgres.postgres /home/postgres sudo chmod -R 700 /home/postgres sudo usermod -d /home/postgres/ postgres All good to here. Next, restart the server and configure the database using these installation instructions: sudo apt-get install postgresql pgadmin3 sudo /etc/init.d/postgresql-8.4 stop sudo vi /etc/postgresql/8.4/main/postgresql.conf Change data_directory to /home/postgres/main sudo /etc/init.d/postgresql-8.4 start sudo -u postgres psql postgres \password postgres sudo -u postgres createdb climate pgadmin3 Use pgadmin3 to configure the database and create a schema. A New Hope The episode began in a remote shell known as bash, with both databases running, and the installation of a command with a most unusual logo: SQL Fairy. perl Makefile.PL sudo make install sudo apt-get install perl-doc (strangely, it is not called perldoc) perldoc SQL::Translator::Manual Extract a PostgreSQL-friendly DDL and all the MySQL data: sqlt -f DBI --dsn dbi:mysql:climate --db-user user --db-password password -t PostgreSQL > climate-pg-ddl.sql mysqldump --skip-add-locks --complete-insert --no-create-db --no-create-info --quick --result-file="climate-my.sql" --databases climate --skip-comments -u root -p The Database Strikes Back Recreate the structure in PostgreSQL as follows: pgadmin3 (switch to it) Click the Execute arbitrary SQL queries icon Open climate-pg-ddl.sql Search for TABLE " replace with TABLE climate." (insert the schema name climate) Search for on " replace with on climate." (insert the schema name climate) Press F5 to execute This results in: Query returned successfully with no result in 122 ms. Replies of the Jedi At this point I am stumped. Where do I go from here (what are the steps) to convert climate-my.sql to climate-pg.sql so that they can be executed against PostgreSQL? How to I make sure the indexes are copied over correctly (to maintain referential integrity; I don't have constraints at the moment to ease the transition)? How do I ensure that adding new rows in PostgreSQL will start enumerating from the index of the last row inserted (and not conflict with an existing primary key from the sequence)? Resources A fair bit of information was needed to get this far: https://help.ubuntu.com/community/PostgreSQL http://articles.sitepoint.com/article/site-mysql-postgresql-1 http://wiki.postgresql.org/wiki/Converting_from_other_Databases_to_PostgreSQL#MySQL http://pgfoundry.org/frs/shownotes.php?release_id=810 http://sqlfairy.sourceforge.net/ Thank you!

  Read the article

• Using nginx's proxy_redirect when the response location's domain varies

  - by Chalky

  I am making an web app using SoundCloud's API. Requesting an MP3 to stream involves two requests. I'll give an example. Firstly: http://api.soundcloud.com/tracks/59815100/stream This returns a 302 with a temporary link to the actual MP3 (which varies each time), for example: http://ec-media.soundcloud.com/xYZk0lr2TeQf.128.mp3?ff61182e3c2ecefa438cd02102d0e385713f0c1faf3b0339595667fd0907ea1074840971e6330e82d1d6e15dd660317b237a59b15dd687c7c4215ca64124f80381e8bb3cb5&AWSAccessKeyId=AKIAJ4IAZE5EOI7PA7VQ&Expires=1347621419&Signature=Usd%2BqsuO9wGyn5%2BrFjIQDSrZVRY%3D The issue I had was that I am attempting to load the MP3 via JavaScript's XMLHTTPRequest, and for security reasons the browser can't follow the 302, as ec-media.soundcloud.com does not set a header saying it is safe for the browser to access via XMLHTTPRequest. So instead of using the SoundCloud URL, I set up two locations in nginx, so the browser only interacts with the server my app is hosted on and no security errors come up: location /soundcloud/tracks/ { # rewrite URL to match api.soundcloud.com's URL structure rewrite \/soundcloud\/tracks\/(\d*) /tracks/$1/stream break; proxy_set_header Host api.soundcloud.com; proxy_pass http://api.soundcloud.com; # the 302 will redirect to /soundcloud/media instead of the original domain proxy_redirect http://ec-media.soundcloud.com /soundcloud/media; } location /soundcloud/media/ { rewrite \/soundcloud\/media\/(.*) /$1 break; proxy_set_header Host ec-media.soundcloud.com; proxy_pass http://ec-media.soundcloud.com; } So myserver/soundcloud/tracks/59815100 returns a 302 to /myserver/soundcloud/media/xYZk0lr2TeQf.128.mp3...etc, which then forwards the MP3 on. This works! However, I have hit a snag. Sometimes the 302 location is not ec-media.soundcloud.com, it's ak-media.soundcloud.com. There are possibly even more servers out there and presumably more could appear at any time. Is there any way I can handle an arbitrary 302 location without having to manually enter each possible variation? Or is it possible for nginx to handle the redirect and return the response of the second step? So myserver/soundcloud/tracks/59815100 follows the 302 behind the scenes and returns the MP3? The browser automatically follows the redirect, so I can't do anything with the initial response on the client side. I am new to nginx and in a bit over my head so apologies if I've missed something obvious, or it's beyond the scope of nginx. Thanks a lot for reading.

  Read the article

• How do I parse file paths separated by a space in a string?

  - by user1130637

  Background: I am working in Automator on a wrapper to a command line utility. I need a way to separate an arbitrary number of file paths delimited by a single space from a single string, so that I may remove all but the first file path to pass to the program. Example input string: /Users/bobby/diddy dum/ding.mp4 /Users/jimmy/gone mia/come back jimmy.mp3 ... Desired output: /Users/bobby/diddy dum/ding.mp4 Part of the problem is the inflexibility on the Automator end of things. I'm using an Automator action which returns unescaped POSIX filepaths delimited by a space (or comma). This is unfortunate because: 1. I cannot ensure file/folder names will not contain either a space or comma, and 2. the only inadmissible character in Mac OS X filenames (as far as I can tell) is :. There are options which allow me to enclose the file paths in double or single quotes, or angle brackets. The program itself accepts the argument of the aforementioned input string, so there must be a way of separating the paths. I just do not have a keen enough eye to see how to do it with sed or awk. At first I thought I'll just use sed to replace every [space]/ with [newline]/ and then trim all but the first line, but that leaves the loophole open for folders whose names end with a space. If I use the comma delimiter, the same happens, just for a comma instead. If I encapsulate in double or single quotation marks, I am opening another can of worms for filenames with those characters. The image/link is the relevant part of my Automator workflow. -- UPDATE -- I was able to achieve what I wanted in a rather roundabout way. It's hardly elegant but here is working generalized code: path="/Users/bobby/diddy dum/ding.mp4 /Users/jimmy/gone mia/come back jimmy.mp3" # using colon because it's an inadmissible Mac OS X # filename character, perfect for separating # also, unlike [space], multiple colons do not collapse IFS=: # replace all spaces with colons colpath=$(echo "$path" | sed 's/ /:/g') # place words from colon-ized file path into array # e.g. three spaces -> three colons -> two empty words j=1 for word in $colpath do filearray[$j]="$word" j=$j+1 done # reconstruct file path word by word # after each addition, check file existence # if non-existent, re-add lost [space] and continue until found name="" for seg in "${filearray[@]}" do name="$name$seg" if [[ -f "$name" ]] then echo "$name" break fi name="$name " done All this trouble because the default IFS doesn't count "emptiness" between the spaces as words, but rather collapses them all.

  Read the article

• PPTP VPN Not Working - Peer failed CHAP authentication, PTY read or GRE write failed

  - by armani

  Brand-new install of CentOS 6.3. Followed this guide: http://www.members.optushome.com.au/~wskwok/poptop_ads_howto_1.htm And I got PPTPd running [v1.3.4]. I got the VPN to authenticate users against our Active Directory using winbind, smb, etc. All my tests to see if I'm still authenticated to the AD server pass ["kinit -V [email protected]", "smbclient", "wbinfo -t"]. VPN users were able to connect for like . . . an hour. I tried connecting from my Android phone using domain credentials and saw that I got an IP allocated for internal VPN users [which I've since changed the range, but even setting it back to the initial doesn't work]. Ever since then, no matter what settings I try, I pretty much consistently get this in my /var/log/messages [and the VPN client fails]: [root@vpn2 ~]# tail /var/log/messages Aug 31 15:57:22 vpn2 pppd[18386]: pppd 2.4.5 started by root, uid 0 Aug 31 15:57:22 vpn2 pppd[18386]: Using interface ppp0 Aug 31 15:57:22 vpn2 pppd[18386]: Connect: ppp0 <--> /dev/pts/1 Aug 31 15:57:22 vpn2 pptpd[18385]: GRE: Bad checksum from pppd. Aug 31 15:57:24 vpn2 pppd[18386]: Peer armaniadm failed CHAP authentication Aug 31 15:57:24 vpn2 pppd[18386]: Connection terminated. Aug 31 15:57:24 vpn2 pppd[18386]: Exit. Aug 31 15:57:24 vpn2 pptpd[18385]: GRE: read(fd=6,buffer=8059660,len=8196) from PTY failed: status = -1 error = Input/output error, usually caused by unexpected termination of pppd, check option syntax and pppd logs Aug 31 15:57:24 vpn2 pptpd[18385]: CTRL: PTY read or GRE write failed (pty,gre)=(6,7) Aug 31 15:57:24 vpn2 pptpd[18385]: CTRL: Client 208.54.86.242 control connection finished Now before you go blaming the firewall [all other forum posts I find seem to go there], this VPN server is on our DMZ network. We're using a Juniper SSG-5 Gateway, and I've assigned a WAN IP to the VPN box itself, zoned into the DMZ zone. Then, I have full "Any IP / Any Protocol" open traffic rules between DMZ<--Untrust Zone, and DMZ<--Trust Zone. I'll limit this later to just the authenticating traffic it needs, but for now I think we can rule out the firewall blocking anything. Here's my /etc/pptpd.conf [omitting comments]: option /etc/ppp/options.pptpd logwtmp localip [EXTERNAL_IP_ADDRESS] remoteip [ANOTHER_EXTERNAL_IP_ADDRESS, AND HAVE TRIED AN ARBITRARY GROUP LIKE 5.5.0.0-100] Here's my /etc/ppp/options.pptpd.conf [omitting comments]: name pptpd refuse-pap refuse-chap refuse-mschap require-mschap-v2 require-mppe-128 ms-dns 192.168.200.42 # This is our internal domain controller ms-wins 192.168.200.42 proxyarp lock nobsdcomp novj novjccomp nologfd auth nodefaultroute plugin winbind.so ntlm_auth-helper "/usr/bin/ntlm_auth --helper-protocol=ntlm-server-1" Any help is GREATLY appreciated. I can give you any more info you need to know, and it's a new test server, so I can perform any tests/reboots required to get it up and going. Thanks a ton.

  Read the article

• iptables management tools for large scale environment

  - by womble

  The environment I'm operating in is a large-scale web hosting operation (several hundred servers under management, almost-all-public addressing, etc -- so anything that talks about managing ADSL links is unlikely to work well), and we're looking for something that will be comfortable managing both the core ruleset (around 12,000 entries in iptables at current count) plus the host-based rulesets we manage for customers. Our core router ruleset changes a few times a day, and the host-based rulesets would change maybe 50 times a month (across all the servers, so maybe one change per five servers per month). We're currently using filtergen (which is balls in general, and super-balls at our scale of operation), and I've used shorewall in the past at other jobs (which would be preferable to filtergen, but I figure there's got to be something out there that's better than that). The "musts" we've come up with for any replacement system are: Must generate a ruleset fairly quickly (a filtergen run on our ruleset takes 15-20 minutes; this is just insane) -- this is related to the next point: Must generate an iptables-restore style file and load that in one hit, not call iptables for every rule insert Must not take down the firewall for an extended period while the ruleset reloads (again, this is a consequence of the above point) Must support IPv6 (we aren't deploying anything new that isn't IPv6 compatible) Must be DFSG-free Must use plain-text configuration files (as we run everything through revision control, and using standard Unix text-manipulation tools are our SOP) Must support both RedHat and Debian (packaged preferred, but at the very least mustn't be overtly hostile to either distro's standards) Must support the ability to run arbitrary iptables commands to support features that aren't part of the system's "native language" Anything that doesn't meet all these criteria will not be considered. The following are our "nice to haves": Should support config file "fragments" (that is, you can drop a pile of files in a directory and say to the firewall "include everything in this directory in the ruleset"; we use configuration management extensively and would like to use this feature to provide service-specific rules automatically) Should support raw tables Should allow you to specify particular ICMP in both incoming packets and REJECT rules Should gracefully support hostnames that resolve to more than one IP address (we've been caught by this one a few times with filtergen; it's a rather royal pain in the butt) The more optional/weird iptables features that the tool supports (either natively or via existing or easily-writable plugins) the better. We use strange features of iptables now and then, and the more of those that "just work", the better for everyone.

  Read the article

• Generating/managing config files for hosted application

  - by mfinni

  I asked a question about config management, and haven't seen a reply. It's possible my question was too vague, so let's get down to brass tacks. Here's the process we follow when onboarding a new customer instance into our hosted application : how would you manage this? I'm leaning towards a Perl script to populate templates to generate shell scripts, config files, XML config files, etc. Looking briefly at CFengine and Chef, it seems like they're not going to reduce the amount of work, because I'd still have to manually specify all of the changes/edits within the tool. Doesn't seem to be much of a gain over touching the config files directly. We add a stanza to the main config file for the core (3rd-party) application. This stanza has values that defines the instance (customer) name the TCP listener port for this instance (not one currently used) the DB2 database name (serial numeric identifier, already exists, they get prestaged for us by the DBAs) three sub-config files, by name - they need to be created from 3 templates and be named after the instance The sub-config files define: The filepath for the DB2 volumes The filepath for the storage of objects The filepath for just one of the DB2 volumes (yes, redundant to the first item. We run some application commands, start the instance We do some LDAP thingies (make an OU for the instance, etc.) We add a stanza to the config file for our security listener that acts as a passthrough to LDAP instance name LDAP OU TCP port for instance DB2 database name We restart the security listener (off-hours), change the main config file from item 1, stop and restart the instance. It is now authenticating via LDAP. We add the stop and start commands for this instance to the HA failover scripts. We import an XML config file into the instance that defines things for the actual application for the customer - user names, groups, permissions, and business rules. The XML is supplied by the implementation team. Now, we configure the dataloading application We add a stanza to the existing top-level config file that points to a new customer-level config file. The new customer-level config file includes: the instance (customer) name the DB2 database name arbitrary number of sub-config files, by name Each of the sub-config files defines: filepaths to the directories for ingestion, feedback, backup, and failure those filepaths have a common path to a customer-specific folder, and then one folder for each sub-config file Each of those filepaths needs to be created We need to add this customer instance to our monitoring scripts that confirm the proper processes are running and can be logged into. Of course, those monitoring config files include the instance name, the TCP port, the DB2 database name, etc. There's also a reporting application that needs to be configured for the new instance. You get the idea. There's also XML that is loaded into WAS by the middleware team. We give them the values for them to plug into the XML - they could very easily hand us the template and we could give them back completed XML.

  Read the article

• Diff 2 files while ignoring parts of lines

  - by Millianz

  I would like to diff a file system. Currently my bash script prints out the file system recursively into a file (ls -l -R) and diffs it with an expected output. An example for a line in this file would be: drw---- 100000f3 00000400 0 ./foo/ My current diff command is diff "$TEMP_LOG" "$DIFF_FILE_OUT" --strip-trailing-cr --changed-group-format='%' --unchanged-group-format='' "$SubLog" As you can see I ignore additional lines in the current output file, I only care about lines that match with the master output. I now have the problem though that some files may differ in size, or a folder might even have a different name, but due to it's location I know what access rights it should have. For example: Output: ------- 00000000 00000000 528 ./foo/bar.txt Master: ------- 00000000 00000000 200 ./foo/bar.txt Only the size differs here, and it doesn't matter, I would like to just ignore certain parts of the diff, kind of like an ansi c comment. Master: ------- 00000000 00000000 /*200*/ ./foo/bar.txt -- OR -- Master: d------ 00000000 00000000 /*10*/ ./foo//*123123*///*76456546*//bar.txt Output: d------ 00000000 00000000 0 ./foo/asd/sdf/bar.txt And still have it diff correctly. Is this even possible with diff, or will I have to write a custom script for it? Since I'm fairly new to cygwin I might be using the completely wrong tool all together, I'm happy for any suggestions. Update: Taking a step back, here is the general task at hand that I want to achieve. I want to write a script that checks the file system to see if the read/write permissions are set up correctly. The structure of the file system is under my control, so I don't have to worry about it changing too much. Sometimes folders/files might not be present, but if they are their permissions must be checked. For Example assume that the following is a snapshot of the current file system structure drw ./foo drw ./foo/bar -rw ./foow/bar/bar.txt drw ./foo/baz -rw ./foo/baz/baz.txt And this is what the file system structure might dictate, i.e. if these folders / files are present, the permissions must match. drw ./foo drw ./foo/bar -rw ./foo/bar/bar.txt --- ./foo/bar/foobar.txt drw ./foo/baz -rw ./foo/baz/foobaz.txt In this case the file system checked out ok, since all files present match their expected values. The situation becomes more complicated as soon as certain folders might have any arbitrary name, only due to their location I know what their permissions should be. Assume that the directory ./foo/bar in the above example might be such a case, i.e. instead of bar the folder could have any name, but still match the -rw permissions. This seems like a very complicated situation, and I'm not even sure if I can solve it with bash scripting alone. I might have to write an actual application.

  Read the article

< Previous Page | 68 69 70 71 72 73 74 75 76 77 78 79  | Next Page >