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  • Python/Django: log to console under runserver, log to file under Apache

    - by Justin Grant
    How can I send trace messages to the console (like print) when I'm running my Django app under manage.py runserver, but have those messages sent to a log file when I'm running the app under Apache? I reviewed Django logging and although I was impressed with its flexibility and configurability for advanced uses, I'm still stumped with how to handle my simple use-case. My apologies for not being able to find the answer elsewhere-- this is a newbie question I know.

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  • Optimizing Transaction Log Throughput

    As a DBA, it is vital to manage transaction log growth explicitly, rather than let SQL Server auto-growth events "manage" it for you. If you undersize the log, and then let SQL Server auto-grow it in small increments, you'll end up with a very fragmented log. Examples in the article, extracted from SQL Server Transaction Log Management by Tony Davis and Gail Shaw, demonstrate how this can have a significant impact on the performance of any SQL Server operations that need to read the log.

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  • rails test.log is always empty

    - by Raiden
    All the log entries generated when running tests with 'rake' are written to my development.log instead of test.log file Do I have to explicitly enable logging for test in enviornments/test.config?? (I'm using 'turn' gem to format test output, Can that cause an issue?) I'm running rails 2.3.5, ruby 1.8.7 I've all these gems installed for RAILS_ENV=test. Any help is appreciated. -[I] less -[I] treetop = 1.4.2 - [I] polyglot = 0.2.5 - [I] mutter = 0.4.2 - [I] mysql - [I] authlogic - [R] activesupport - [I] turn - [I] ansi = 1.1.0 - [I] facets = 2.8.0 - [I] rspec = 1.2.0 - [I] rspec-rails = 1.2.0 - [I] rspec = 1.3.0 - [R] rack = 1.0.0 - [I] webrat = 0.4.3 - [I] nokogiri = 1.2.0 - [R] rack = 1.0 - [I] rack-test = 0.5.3 - [R] rack = 1.0 - [I] cucumber = 0.2.2 - [I] term-ansicolor = 1.0.4 - [I] treetop = 1.4.2 - [I] polyglot = 0.2.5 - [I] polyglot = 0.2.9 - [R] builder = 2.1.2 - [I] diff-lcs = 1.1.2 - [R] json_pure = 1.2.0 - [I] cucumber-rails - [I] cucumber = 0.6.2 - [I] term-ansicolor = 1.0.4 - [I] treetop = 1.4.2 - [I] polyglot = 0.2.5 - [I] polyglot = 0.2.9 - [R] builder = 2.1.2 - [I] diff-lcs = 1.1.2 - [R] json_pure = 1.2.0 - [I] database_cleaner = 0.2.3 - [I] launchy - [R] rake = 0.8.1 - [I] configuration = 0.0.5 - [I] faker - [I] populator - [R] flog = 2.1.0 - [R] flay - [I] rcov - [I] reek - [R] ruby_parser ~ 2.0 - [I] ruby2ruby ~ 1.2 - [R] sexp_processor ~ 3.0 - [R] ruby_parser ~ 2.0 - [R] sexp_processor ~ 3.0 - [I] roodi - [R] ruby_parser - [I] gruff - [I] rmagick - [I] ruby-prof - [R] jscruggs-metric_fu = 1.1.5 - [I] factory_girl - [I] notahat-machinist

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  • Log 2 N generic comparison tree

    - by Morano88
    Hey! I'm working on an algorithm for Redundant Binary Representation (RBR) where every two bits represent a digit. I designed the comparator that takes 4 bits and gives out 2 bits. I want to make the comparison in log 2 n so If I have X and Y .. I compare every 2 bits of X with every 2 bits of Y. This is smooth if the number of bits of X or Y equals n where (n = 2^X) i.e n = 2,4,8,16,32,... etc. Like this : However, If my input let us say is 6 or 10 .. then it becomes not smooth and I have to take into account some odd situations like this : I have a shallow experience in algorithms .. is there a generic way to do it .. so at the end I get only 2 bits no matter what the input is ? I just need hints or pseudo-code. If my question is not appropriate here .. so feel free to flag it or tell me to remove it. I'm using VHDL by the way!

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  • Command to find the source package of a binary?

    - by Delan Azabani
    I know there's a which command, that echoes the full name of a binary (e.g. which sh). However, I'm fairly sure there's a command that echoes the package that provides a particular binary. Is there such a command? If so, what is it? I'd like to be able to run this: commandName ls and get coreutils for example.

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  • Handling log-in / log-out via Objective-c

    - by squeezemylime
    Having a real problem with this one...Tried using cookies to store variables, etc. but no luck. Writing an iPhone app where the User has to log in. There is an HTTPS call to get the person's userid, which is used practically everywhere else in the app, so that either has to be stored in a global variable or a cookie (for sending messages to other users, etc.) I tried the cookie route, but am having great difficulty storing (and retriving) a user ID in a cookie. The User should be able to then close out of the app and then reboot it and have the app retain their User ID as well, so I'm not sure global variables are necessarily the solution to this. Are there any best practices or suggestions?

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  • SQL Server 2008 log issue

    - by George2
    Hello everyone, I am using SQL Server 2008 Enterprise. Under logs folder, in my machine it is C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\Log, there are three kinds of files, ERRORLOG, ERRORLOG.1, ERRORLOG.2 ... ERRORLOG.6; FDLAUNCHERRORLOG, FDLAUNCHERRORLOG.1, FDLAUNCHERRORLOG.2, ... FDLAUNCHERRORLOG.6; log_207.trc, log_208.trc, ... My question is what are the differnet function of such log files? And why there are files ends with .1, .2, etc? thanks in advance, George

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  • hundreds of databases sql server log shipping

    - by Oliver
    SQL Server 2005 Standard 64x, with 300+ tiny databases currently (5MB each), user base adds databases as needed. Want to implement log shipping for warm standby, but not via the wizard, since that looks like it adds 3 jobs (1 on primary, 2 on secondary) for each log-shipped database. Do I try to write my own or use something like Quest's LiteSpeed? Or am I being too squeamish about having hundreds of SQL Server Agent jobs and all of them firing off (or worse, would I have to try to time them)? All advice welcome.

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  • log4net: log information into different log files

    - by Daoming Yang
    I have the following configurations in my web.config file, but how can I log the information into data.txt and general.txt separately in C#? Could anyone provide some sample code for me? <appender name="GeneralLog" type="log4net.Appender.RollingFileAppender"> <file value="App_Data/Logs/general.txt" /> <appendToFile value="true" /> <maximumFileSize value="2MB" /> <rollingStyle value="Size" /> <maxSizeRollBackups value="5" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%d{HH:mm:ss.fff} [%t] %-5p %c - %m%n" /> </layout> </appender> <appender name="DataLog" type="log4net.Appender.RollingFileAppender"> <file value="App_Data/Logs/data.txt" /> <appendToFile value="true" /> <maximumFileSize value="2MB" /> <rollingStyle value="Size" /> <maxSizeRollBackups value="5" /> <layout type="log4net.Layout.PatternLayout"> <conversionPattern value="%d{HH:mm:ss.fff} [%t] %-5p %c - %m%n" /> </layout> </appender>

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  • Which is best Postfix Log analyzer?

    - by Anto Binish Kaspar
    Which is best Postfix Log analyzer? We are looking for good log analyzer for postfix. We need to analyze the following How many mails queued ? How many mails not delivered ? Why mails are not delivered ? And is it possible to view the subject for the all mail status instead of message id? I mean to review the status of the single mail. We are using Sawmill analyzer now. But the management is not satisfied with the report from the sawmaill, since its missing single message status and subject.

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  • How To see keyboard log of 3 computer from another computer?

    - by NT
    Hello, I have a small office with 3 computers + my own laptop without any network between these computers. I would like to see keyboard log of each worker computer from my laptop without disturbing my workers. I should be able to see each keyboard log from my laptop (from GUI or e-mail message) Also, is it possible to limit the logging? For example I would not to see log of msn messenger, but I should see log of IE,Outlook etc...?

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  • Understanding Application binary interface (ABI)

    - by Tim
    I am trying to understand the concept of Application binary interface (ABI). From The Linux Kernel Primer: An ABI is a set of conventions that allows a linker to combine separately compiled modules into one unit without recompilation, such as calling conventions, machine interface, and operating-system interface. Among other things, an ABI defines the binary interface between these units. ... The benefits of conforming to an ABI are that it allows linking object files compiled by different compilers. From Wikipedia: an application binary interface (ABI) describes the low-level interface between an application (or any type of) program and the operating system or another application. ABIs cover details such as data type, size, and alignment; the calling convention, which controls how functions' arguments are passed and return values retrieved; the system call numbers and how an application should make system calls to the operating system; and in the case of a complete operating system ABI, the binary format of object files, program libraries and so on. I was wondering whether ABI depends on both the instruction set and the OS. Are the two all that ABI depends on? What kinds of role does ABI play in different stages of compilation: preprocessing, conversion of code from C to Assembly, conversion of code from Assembly to Machine code, and linking? From the first quote above, it seems to me that ABI is needed for only linking stage, not the other stages. Is it correct? When is ABI needed to be considered? Is ABI needed to be considered during programming in C, Assembly or other languages? If yes, how are ABI and API different? Or is it only for linker or compiler? Is ABI specified for/in machine code, Assembly language, and/or of C?

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  • Getting really weird entries in Apache log from Baidu.com?

    - by Undo
    I was looking through my server logs today, and I noticed this: (it's all one row) 118.244.179.250 - - [16/Oct/2013:20:59:25 +0000] "GET http://www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttphttp/www.baidu.comhttphttphttphttphttp/www.baidu.comhttphttphttphttp/www.baidu.comhttphttphttp/www.baidu.comhttphttp/www.baidu.comhttp/www.baidu.com/ HTTP/1.1" 301 4605 "http://www.baidu.com/" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E)" "GET http://www.baidu.comhttphttphttphttphttp...? Am I doing something wrong? Am I hosting someone else's website without knowing it? Is a guy named baidu trying to drive me crazy?

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  • SQL SERVER – Detect Virtual Log Files (VLF) in LDF

    - by pinaldave
    In one of the recent training engagements, I was asked if it true that there are multiple small log files in the large log file (LDF). I found this question very interesting as the answer is yes. Multiple small Virtual Log Files commonly known as VLFs together make an LDF file. The writing of the VLF is sequential and resulting in the writing of the LDF file is sequential as well. This leads to another talk that one does not need more than one log file in most cases. However, in short, you can use following DBCC command to know how many Virtual Log Files or VLFs are present in your log file. DBCC LOGINFO You can find the result of above query to something as displayed in following image. You can see the column which is marked as 2 which means it is active VLF and the one with 0 which is inactive VLF. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • using egrep to find missing @ in log

    - by jols
    I am using the following command to find log entries that are the result of a log in to the email server: egrep '_login[^ ]' /var/log/exim_mainlog That works fine to find entries that contain content like this: P=esmtpa A=courier_login:[email protected] S=1573 id=f1cd08396,... But what I need to do is to change my grep statement, so that it finds single word logins that do not use the @ sign, like so: P=esmtpa A=courier_login:name S=1573 id=f1cd08396,... Where the log in before was "[email protected]", but in the second log entry, the log in used was only "name". Is this possible using grep or egrep, perhaps in some kind of a compound statement? Thanks much.

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  • Are log records removed from ldf file for rollbacks?

    - by TiborKaraszi
    Seems like a simple enough question, right? This question (but more targeted, read on) was raised in an MCT forum. While the discussion was on-going and and I tried to come up with answers, I realized that this question are really several questions. First, what is a rollback? I can see three different types of rollbacks (there might be more, of course): Regular rollback, as in ROLLBACK TRAN (or lost/terminated connection) Rollback done by restore recovery. I.e., end-time of backup included some transaciton...(read more)

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  • log parser error

    - by Preetham
    Hi Guys, I have never used log parser before.. well I am getting this error now.. i don't know the reason.. Retrieving the COM class factory for component with CLSID {8CFEBA94-3FC2-45CA-B9A5-9EDACF704F66} failed due to the following error: 80040154. can ya help me out with this.. :)

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  • Log MySQL Query In Kohana 3

    - by Asif
    Hi All, I am using Kohana 3. I want to log the MySQL queries being executed by an application. The reason to determine the query of type INSERT,UPDATE and DELETE which are being executed in a process and store them in another MySQL table with date-time for further reference. Can anybody tell how can I achieve this?

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  • Seeing release markers in svn log

    - by chuanose
    Whenever we make a release of a project we'll create a tag to capture the snapshot. It will be very helpful to be able to see which revisions in the trunk history were used in certain releases. I know the TortoiseSVN revision graph shows this information, but I'm wondering if there's a way to see it in the command-line svn log? I'm coming from a Clearcase background where we'll be able to see the release labels in the history.

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  • SQL SERVER – Backing Up and Recovering the Tail End of a Transaction Log – Notes from the Field #042

    - by Pinal Dave
    [Notes from Pinal]: The biggest challenge which people face is not taking backup, but the biggest challenge is to restore a backup successfully. I have seen so many different examples where users have failed to restore their database because they made some mistake while they take backup and were not aware of the same. Tail Log backup was such an issue in earlier version of SQL Server but in the latest version of SQL Server, Microsoft team has fixed the confusion with additional information on the backup and restore screen itself. Now they have additional information, there are a few more people confused as they have no clue about this. Previously they did not find this as a issue and now they are finding tail log as a new learning. Linchpin People are database coaches and wellness experts for a data driven world. In this 42nd episode of the Notes from the Fields series database expert Tim Radney (partner at Linchpin People) explains in a very simple words, Backing Up and Recovering the Tail End of a Transaction Log. Many times when restoring a database over an existing database SQL Server will warn you about needing to make a tail end of the log backup. This might be your reminder that you have to choose to overwrite the database or could be your reminder that you are about to write over and lose any transactions since the last transaction log backup. You might be asking yourself “What is the tail end of the transaction log”. The tail end of the transaction log is simply any committed transactions that have occurred since the last transaction log backup. This is a very crucial part of a recovery strategy if you are lucky enough to be able to capture this part of the log. Most organizations have chosen to accept some amount of data loss. You might be shaking your head at this statement however if your organization is taking transaction logs backup every 15 minutes, then your potential risk of data loss is up to 15 minutes. Depending on the extent of the issue causing you to have to perform a restore, you may or may not have access to the transaction log (LDF) to be able to back up those vital transactions. For example, if the storage array or disk that holds your transaction log file becomes corrupt or damaged then you wouldn’t be able to recover the tail end of the log. If you do have access to the physical log file then you can still back up the tail end of the log. In 2013 I presented a session at the PASS Summit called “The Ultimate Tail Log Backup and Restore” and have been invited back this year to present it again. During this session I demonstrate how you can back up the tail end of the log even after the data file becomes corrupt. In my demonstration I set my database offline and then delete the data file (MDF). The database can’t become more corrupt than that. I attempt to bring the database back online to change the state to RECOVERY PENDING and then backup the tail end of the log. I can do this by specifying WITH NO_TRUNCATE. Using NO_TRUNCATE is equivalent to specifying both COPY_ONLY and CONTINUE_AFTER_ERROR. It as its name says, does not try to truncate the log. This is a great demo however how could I achieve backing up the tail end of the log if the failure destroys my entire instance of SQL and all I had was the LDF file? During my demonstration I also demonstrate that I can attach the log file to a database on another instance and then back up the tail end of the log. If I am performing proper backups then my most recent full, differential and log files should be on a server other than the one that crashed. I am able to achieve this task by creating new database with the same name as the failed database. I then set the database offline, delete my data file and overwrite the log with my good log file. I attempt to bring the database back online and then backup the log with NO_TRUNCATE just like in the first example. I encourage each of you to view my blog post and watch the video demonstration on how to perform these tasks. I really hope that none of you ever have to perform this in production, however it is a really good idea to know how to do this just in case. It really isn’t a matter of “IF” you will have to perform a restore of a production system but more of a “WHEN”. Being able to recover the tail end of the log in these sever cases could be the difference of having to notify all your business customers of data loss or not. If you want me to take a look at your server and its settings, or if your server is facing any issue we can Fix Your SQL Server. Note: Tim has also written an excellent book on SQL Backup and Recovery, a must have for everyone. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: Notes from the Field, PostADay, SQL, SQL Authority, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • Collaborative Whiteboard using WebSocket in GlassFish 4 - Text/JSON and Binary/ArrayBuffer Data Transfer (TOTD #189)

    - by arungupta
    This blog has published a few blogs on using JSR 356 Reference Implementation (Tyrus) as its 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 TOTD #186: Custom Text and Binary Payloads using WebSocket One of the typical usecase for WebSocket is online collaborative games. This Tip Of The Day (TOTD) explains a sample that can be used to build such games easily. The application is a collaborative whiteboard where different shapes can be drawn in multiple colors. The shapes drawn on one browser are automatically drawn on all other peer browsers that are connected to the same endpoint. The shape, color, and coordinates of the image are transfered using a JSON structure. A browser may opt-out of sharing the figures. Alternatively any browser can send a snapshot of their existing whiteboard to all other browsers. Take a look at this video to understand how the application work and the underlying code. The complete sample code can be downloaded here. The code behind the application is also explained below. The web page (index.jsp) has a HTML5 Canvas as shown: <canvas id="myCanvas" width="150" height="150" style="border:1px solid #000000;"></canvas> And some radio buttons to choose the color and shape. By default, the shape, color, and coordinates of any figure drawn on the canvas are put in a JSON structure and sent as a message to the WebSocket endpoint. The JSON structure looks like: { "shape": "square", "color": "#FF0000", "coords": { "x": 31.59999942779541, "y": 49.91999053955078 }} The endpoint definition looks like: @WebSocketEndpoint(value = "websocket",encoders = {FigureDecoderEncoder.class},decoders = {FigureDecoderEncoder.class})public class Whiteboard { As you can see, the endpoint has decoder and encoder registered that decodes JSON to a Figure (a POJO class) and vice versa respectively. The decode method looks like: public Figure decode(String string) throws DecodeException { try { JSONObject jsonObject = new JSONObject(string); return new Figure(jsonObject); } catch (JSONException ex) { throw new DecodeException("Error parsing JSON", ex.getMessage(), ex.fillInStackTrace()); }} And the encode method looks like: public String encode(Figure figure) throws EncodeException { return figure.getJson().toString();} FigureDecoderEncoder implements both decoder and encoder functionality but thats purely for convenience. But the recommended design pattern is to keep them in separate classes. In certain cases, you may even need only one of them. On the client-side, the Canvas is initialized as: var canvas = document.getElementById("myCanvas");var context = canvas.getContext("2d");canvas.addEventListener("click", defineImage, false); The defineImage method constructs the JSON structure as shown above and sends it to the endpoint using websocket.send(). An instant snapshot of the canvas is sent using binary transfer with WebSocket. The WebSocket is initialized as: var wsUri = "ws://localhost:8080/whiteboard/websocket";var websocket = new WebSocket(wsUri);websocket.binaryType = "arraybuffer"; The important part is to set the binaryType property of WebSocket to arraybuffer. This ensures that any binary transfers using WebSocket are done using ArrayBuffer as the default type seem to be blob. The actual binary data transfer is done using the following: var image = context.getImageData(0, 0, canvas.width, canvas.height);var buffer = new ArrayBuffer(image.data.length);var bytes = new Uint8Array(buffer);for (var i=0; i<bytes.length; i++) { bytes[i] = image.data[i];}websocket.send(bytes); This comprehensive sample shows the following features of JSR 356 API: Annotation-driven endpoints Send/receive text and binary payload in WebSocket Encoders/decoders for custom text payload In addition, it also shows how images can be captured and drawn using HTML5 Canvas in a JSP. How could this be turned in to an online game ? Imagine drawing a Tic-tac-toe board on the canvas with two players playing and others watching. Then you can build access rights and controls within the application itself. Instead of sending a snapshot of the canvas on demand, a new peer joining the game could be automatically transferred the current state as well. Do you want to build this game ? I built a similar game a few years ago. Do somebody want to rewrite the game using WebSocket APIs ? :-) Many thanks to Jitu and Akshay for helping through the WebSocket internals! Here are some references for you: JSR 356: Java API for WebSocket - Specification (Early Draft) and Implementation (already integrated in GlassFish 4 promoted builds) 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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