5 Vi du ve htaccess

Xin chào các bạn, nhất là những bạn đã đang và sẽ là một webmaster 

Bạn là một WM ắt hẳn phải chú trọng đến việc quảng bá website để thu hút traffic. Có rất nhiều yếu tố để đạt được yêu cầu đó mà trong khuôn khổ bài viết hạn hẹp này Việt Coding không thể nói hết. Việt Coding chỉ nói đến việc “viết lại” (rewrite) đường dẫn web (url) của bạn cho đẹp, cho dễ nhớ, nói chung là thân thiện. Thân thiện với cả visitor và các search engine. Bạn nghĩ sao nếu phải gõ tay hoặc copy dòng địa chỉ này paste vào trình duyệt :

/index.php?option=com_content&view=article&id=25:bai-hc-t-cuc-sng&catid=1:news-tonghop&joscclean=1&comment_id=473#josc473

hay bạn chỉ muốn gõ đơn giản như vầy:

/article/25/bai-hoc-tu-cuoc-song/

Tôi có cần trả lời giùm bạn không nhỉ ? 

Bài viết dưới đây sẽ hướng dẫn các bạn sử dụng sức mạnh của tập tin .htaccess, qua đó viết lại đường dẫn website của bạn một cách thân thiện (friendly url).

Hy vọng bạn chưa quên một bài viết khác của Việt Coding cũng nói về .htaccess : Bảo vệ băng thông webblog của bạn bằng htaccess ?

URL Rewriting - Một kỹ thuật quan trọng giúp cho SEO - (Nguồn : Internet)

Đây là 5 ví dụ thông dụng nhất:

1. product.php?id=12 —> product-12.html

Đây là một ví dụ cực kỳ cơ bản của rewrite url, thường dùng để che dấu đuôi PHP:

RewriteEngine on
RewriteRule ^product-([0-9]+).html$ product.php?id=$1

2. product.php?id=12 —> product/ipod-nano/12.html

Một SEO chuyên nghiệp luôn biết khéo léo hiển thị từ khoá chính trên URL. Như trong ví dụ sau, URL hiển thị tên của sản phẩm chính:

RewriteEngine on
RewriteRule ^product/([a-zA-Z0-9_-]+)/([0-9]+).html$ product.php?id=$2

3. Non www URL —> www URL

Nếu bạn muốn khi visitor gõ vào trình duyệt vietcoding.com thì được chuyển thẳng vào www.vietcoding.com thì cấu hình như sau:

RewriteEngine On
RewriteCond %{HTTP_HOST} ^vietcoding.com$
RewriteRule (.*) http://www.vietcoding.com/$1 [R=301,L]

4) vietcoding.com/user.php?username=xyz —> vietcoding.com/xyz

Nếu website của bạn có một lượng lớn thành viên (như mạng xã hội, diễn đàn), đây là một cách rất hay để rút gọn liên kết cho thành viên dễ nhớ

RewriteEngine On
RewriteRule ^([a-zA-Z0-9_-]+)$ user.php?username=$1
RewriteRule ^([a-zA-Z0-9_-]+)/$ user.php?username=$1

5) Chuyển domain vào cấp thư mục:

Trong quá trình phát triển website, luôn luôn có sự thay đổi (về mã nguồn, cơ sở dữ liệu, cấu trúc site,…). Ví dụ vietcoding.com trước giờ vẫn chạy ở thư mục gốc (root), giả sử vì một lý do nào đó, Việt Coding cần dùng root cho việc khác và muốn chuyển webblog hiện tại vào thư mục /blog/ thì sao ?


RewriteEngine On
RewriteCond %{HTTP_HOST} ^vietcoding.com$ [OR]
RewriteCond %{HTTP_HOST} ^www.vietcoding.com$
RewriteCond %{REQUEST_URI} !^/blog/
RewriteRule (.*) /blog/$1

Thế là xong ! Từ nay mọi truy vấn đến vietcoding.com hoặc www.vietcoding.com đều được redirect vào vietcoding.com/blog

Tất nhiên, URL rewriting rất đa dạng và phong phú, tuỳ sự sáng tạo của từng webmaster mà sẽ cho ra những url độc đáo không đụng hàng, ví dụ như:

http://abc.com/Music/#List_Album2,-1,1

http://abc.com/Products/#IPhone|3GS|32G

SVN command

Subversion Commands:

Subversion command summary cheat sheet:

Command	Description
svn --help	List Subversion commands
svn help command Also: ? or h	Help on given "command"
svn add filename svn add directory	Add a file or directory to Subversion CM control. Must also perform: svn ci filename (or svn commit) to upload the file or directory. File will not be available in the repository until a "commit" is performed. If adding a directory, the directory and all of its contents recursively are added. i.e.: svn ci directory svn commit directory svn commit .
svn blame filename svn blame -r RevisionNumber filename Also: praise, annotate, ann	Show file contents with revisions annotated with author information.
svn cat filename	List contents of file under Subversion control.
svn checkout http://node-name/repos/svn/trunk/parentPath/path This creates: path/file1 path/file2 ... svn checkout http://node-name/repos/svn/trunk/parentPath . This creates: path/file1 path/file2 ... Note the difference a "." makes. svn checkout file:///repos/svn/trunk/path/ svn co -r 497 http://node-name/repos/svn/trunk/path file-name Also: svn co https://..., svn://..., and svn+ssh:// MS/Windows: svn co file:///c:/repository/project/trunk	Checkout every file from the path and subdirectories specified below. Creates "working" copy of files and directories. Checkout a repository. Use option "-r" to specify a specific revision other than the latest. The URL "svn://" communicates with an SVN server (port 3690) The URL "http://" comunicates with the Apache server and module mod_dav_svn (port 80) [more common server]
svn cleanup	Cleanup subversion files resulting from escaped processes and crashed.
svn commit filename svn commit --message "Message goes here." filename svn commit -m "Message goes here." filename svn ci filename1 filename2 filename3 svn ci .	Check-in (commit) local "working" file, files or directory and contents (recursively) into Subversion repository. Atomic, i.e. all committed or none, no incomplete check-in.
svn copy source destination_clone Also: svn cp ...	Copy file or directory tree. One can copy from one local working copy to another or to repository server URL's. The sources and destinations can be working copies or URLs.
svn copy http://host/repos/project/trunk http://host/repos/project/tags/TagName-1.4.5 -m "Tag Release 1.4.5"	Tag a release. Takes a snapshot of the repository and assigns a name. This can be performed at any directory branch.
svn copy . http://host/repos/project/tags/TagName-1.4.5 -m "Tag Release 1.4.5"	Tag a release. Takes a snapshot of your local working copy and assigns a name. This can be performed at any directory branch.
svn delete filename svn delete directory Also: del, remove or rm svn rm http://host/repos/project/trunk/file-or-directory	Delete file from repository. The UNIX command rm file-name. Must perform a "commit" to update the repository and local working directory with the changes. i.e.: svn commit .
svn diff filename svn di filename	Show file diffs between SVN repository and your file changes using GNU file diff format. Use GUI diff tools as shown below.
svn diff -r rev1:rev2 filename	Show file diffs between specified versions. Example: svn diff -r 456:459 subfn.cpp Using GUI diff tool: svn diff -r 457:459 --diff-cmd kdiff3 file-name
svn diff filename > patch-file	Generate patch file used by the patch command.
svn export directory	Export directory tree to your file system but it will not be a "working directory" under SVN control.
svn export -r Rev-Number http://node-name/path	Export directory tree of specified version and create local directory tree and files not under SVN control.
svn import local-directory http://node/repos/svn/trunk/directory	Add directory (and files in it recursively) to path in repository specified.
svn info filename	Display information about file or directory. (Date modified, author, revision, path in repository.) Can not specify a URL.
svn list directory svn list file-name	List file or directory of files in repository. Used to browse repository before checkout. If current directory is given (svn list ./), then Subversion will list the repository URL of the current directory.
svn list -r RevisionNumber directory	List directory of files in repository in specified revision.
svn lock filename -m "comment as to why its locked or by whom" (Comment is not required but is often useful)	Lock file to grant exclusive access to one and forbid all others. A commit will unlock the file (unless the "--no-unlock" option is used). A lock can be removed with the commands: svn unlock filename, svnlook and the svnadmin comands (i.e. List: svnadmin lslocks and remove: svnadmin rmlocks filename).
svn log filename svn log . svn log http://URL/path/file svn log -v . svn log -r RevisionNumber http://URL/path/file	Show the Subversion log messages for a set of revision(s) and/or file(s) and/or all directory contents in repository. List verbose. Includes list of all files in change Shows the file changes associated with revision number.
svn merge http://url/path/branch1 http://url/path/branch2 working-local-dir svn merge file1@revJ file2@revK svn merge -r 414:411 http://url/path working-dir svn merge -r 413:HEAD file-name	Merge directory changes into your current working directory or merge a file in Subversion into the file in your working directory. If target is not specified, the identical basename or current directory is assumed. Used to incorporate changes checked in which are not accounted for in your file or to merge branches. Example using GUI merge tool: svn diff -r 459:454 --diff-cmd kdiff3 --extensions '-m' file-name Next, tell subversion that the conflicts have been resolved: svn resolve file-name Finally, check-in file: svn ci file-name or abort changes: svn revert file-name
svn merge --dry-run -r 414:413 http://url/path	Test merge. No changes are made to your local working copy but shows Subversion feedback as if merge was performed.
svn merge -r 414:413 http://url/path svn merge -r 414:413 .	Undo changes committed in revision 414.
svn mkdir directory svn mkdir http://URL/directory	Create a new directory under version control.
svn move directory1 directory2 svn mv directory1 directory2 svn mv file-old-name file-new-name	Rename or move a file or directory. Moves/renames file/directory in repository and in local work area. Must perform svn ci file-new-name after the move for changes to to take place in repository.
svn revert filename	Undo changes in local work files. Throw away local changes.
svn resolved filename	Run this command after resolving merge conflicts. Next "commit" your changes.
svn status svn status -u svn status -u . svn status -uq .	Show status of file changes in current directory and recursively in directories below. Show out of date file info: svn status --show-updates (equivalent: svn status -u) -u: Determines status by comparing your local repository with the server repository. Without this option, the status shown will only be the changes you have made in your local repository. -q: Quiet. Do not print "?: File/directory not under version control" or "!: File/directory missing" extraneous information. First collumn: A: File to be added C: Conflicting changes D: File to be deleted G: File to be merged with updates from server M: File has been modified R: File to be replaced G: File to be merged X: Resource is external to repository (svn:externals) ?: File/directory not under version control !: File/directory missing ~: Versioned item obstructed by some item of a different kind. Second collumn: Modification of properties ' ' no modifications. Working copy is up to date. 'C' Conflicted 'M' Modified '*' Local file different than repository. A newer revision exists on the server. Update will result in merge or possible conflict. Third collumn: Locks ' ' not locked 'L' locked 'S' switched to a branch
svn switch http://server/new-branch svn switch --relocate http://server/old-path http://server/new-path	Switch your local working copy to mirror a new repository branch instead of main trunk or previous branch. Also allows you to point your repository to a new path on the server if the server path changes since you performed a check-out.
svn update svn update filename svn update -r458 filename svn update --ignore-externals ./	Migrate all updates from Subversion repository to your local copy (recusively for all files in the current directory and all below it). If there have been updates to the svn repository since you downloaded the files, subversion will give you the opportunity to merge. Status of files will use the coding as stated above for "status". Files marked with a "C" (conflict) should be merged of reverted. If merged then one can perform a "resolve" and then a "check-in". If a file name is specified, only that file is updated. Can also syncronize to a specified revision given by -r. Use --ignore-externals to avoid the slow processing of externals to a potentially slow distant internet server.

Where RevisionNumber is:

• HEAD: The latest revision in the repository.
• BASE: The "pristine" revision of an item in a working copy. Matches checked out version before any modifications.
• COMMITTED: The last revision in which an item changed before (or at) BASE.
• PREV: The revision just before the last revision in which an item changed. (Technically, COMMITTED - 1.)

---

Example Session:

(Assumes that the repository has already been created. For Subversion repository creation and Subversion server configuration, see the (YoLinux Subversion and Trac tutorial)

• Checkout: svn checkout http://svnserver/repos/svn/trunk/Project1
• Go to source code directory: cd Project1/src
• Edit files:
  • vi file1.cpp
  • vi file2.cpp
• Verify and test: make
  We are ready to check-in the files into the Subversion repository.
• Check repository and report on new revisions and changes others have checked in: svn status -u .
• After many long hours or days of editing and work, get updates others have made: svn update

      U file.h
      C file1.cpp
      G file2.cpp
      ? a.out 

  You will see:
  • U: File was updated with a newer version checked-in since your checkout.
  • G: Automatically merged with no conflicts.
  • C: Not merged due to conflicts. You made changes to the same section of code as the update made by someone else since your checkout.
• For each "conflicted" file there will be three new local files generated by "update":
  • file1.cpp.mine (File - post editing)
  • file1.cpp.rold (BASE - pre editing)
  • file1.cpp.rnew (HEAD - Updated file from repository)
  The file file1.cpp still exists but with svn conflict marker strings added in the file.
  At this point, a check-in will fail until the merge is resolved.
• Merge options:
  • Edit the file file1.cpp
    Text markers are placed in the file to show the conflicts between the "HEAD" and "mine" versions.
    OR
  • tkdiff -conflict file1.cpp
    OR
  • Use a GUI merge tool: kdiff3 file1.cpp.mine file1.cpp.rnew -o file1.cpp
    OR
  • Throw out your changes/abort: svn revert file1.cpp
    No resolve or check-in necessary if file is reverted.
• Verify and test, again: make
• Notify Subversion that conflicts have been resolved: svn resolved file1.cpp
  Note: This also removes the temporary files ".mine" and ".r###".
• Check-in to Subversion repository: svn ci -m "Add comments here" file1.cpp

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Subversion Peg revisions:

Peg revisions are used so Subversion can find a previous version of a resource (file or directory) if its' location was different than it is now. Peg revisions are that extra hint Subversion needs to clear up ambiguity.
$ svn command -r OPERATIVE-REV item@PEG-REV
The default peg revision is BASE for working copy items and HEAD for repository URLs. When no operative revision is provided, it defaults to being the same revision as the peg revision.
The PEG-REV is specified if the resource (file/directory) in question use to appear in a directory which is no longer in the same place or no longer exists. The "peg-revision" must be specified so subversion can look at the directory in that revision so it can find the resource.
If a peg revision is specified without an operative revision, then the operative revision is assumed to be the same as the peg revision.
For more see: http://svnbook.red-bean.com/en/1.5/svn.advanced.pegrevs.html

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Subversion Properties:

Files under revision control can include Subversion keywords which properties can be set with the "propset" command. Keywords are substituted with the Subversion properties and will not appear in the file until a commit is performed. Other properties are used to modify the behavior of Subversion.
The following properties can be set on entities stored in Subversion:

Property	Description
svn:ignore	A newline separated list of file patterns to ignore. List of files/directories to be ignored by svn status
svn:keywords	Valid RCS style keywords are: HeadURL - The URL for the head version of the object. Also: $URL$ LastChangedBy - The last person to modify the file. Also: $Author$ LastChangedDate - The date/time the object was last modified. Will appear as: $LastChangedDate: 2005-07-22 22:02:37 -0700 (Fri, 22 Jul 2005) $ Also: $Date$ LastChangedRevision - Describes the last known revision. Will appear as: $LastChangedRevision: XXX $ where "XXX" is the revision number. Also: $Rev$, Revision $Id$ - A compressed summary of the previous 4 keywords. Example RCS style comment Example Output /* $URL$ $Rev$ $Author$ $Date$ $Id$ */ /* $URL:http://server/svn/path/file.cpp $ $ Rev:2 $ $ Author:Greg $ $ Date:2006-10-12 14:31:84 -0400 (Thu,12 Oct 2006)$ $ Id:file.cpp 3 2006-10-12 18:31:84Z Greg $ */ To turn on keyword processing for $URL$ and $Rev$ set the property svn:keywords and commit the file. The property is not assigned until a commit is performed. Subsequent check-outs and updates will have substitution performed on the working file: svn propset svn:keywords "URL Rev" source-file.cpp To turn this substitution off so that one can edit the original keywords. This also requires a check-in: svn propdel svn:keywords source-file.cpp
svn:executable	Ensure file attribute is executable. Possible values: ON, OFF Example: svn propset svn:executable ON app.exe
svn:eol-style	One of 'native', 'LF', 'CR', 'CRLF'. Specify and maintain specified line ending for text file. LF: Unix, Linux, standards based OS, proprietary legacy systems, etc. CRLF: DOS and Microsoft OSs CR: Response input scripts, etc Example: find ./ -name "*.h" -exec svn propset svn:eol-style LF {} \;
svn:mime-type	The mime type of the file: text/html text/css text/plain image/jpeg ... See file /etc/mime.types for a list of mime types. Examples: svn propset svn:mime-type text/plain file.cpp svn propset svn:mime-type text/html file.html Web pages rendered from subversion will display as HTML source rather than as a web page unless this mime type is applied.
svn:needs-lock	Prevents conflicts for files which can not be contextually merged. i.e. photos, binaries, object libraries.
svn:externals	List of files or directories pointed to. Locate repository where directory specified should be retrieved. The directive propset is not required: svn propedit svn:externals local-target-dir local-target-dir http://server/svn/dir-remote local-target-dir/subdir -r### http://server/svn/dir-remote2 svn update svn commit svn propget svn:externals ./ The property applies to the directory. Subversion can not list or web browse svn:externals. Check-out ("co"), "export" and "log" can be performed. Must set environment variable "EDITOR", "SVN_EDITOR", "VISUAL" or set the Subversion configuration file (~/.subversion/config) attribute editor-cmd. i.e.: export EDITOR=vi Note: Subversion 1.6 introduces file externals in addition to directory externals. The files however must reside in the same repository. Also, the file must point to a location which exists in your local working directory. [Potential Pitfall]: Apply svn externals to directories and not files. (version 1.4) [Potential Pitfall]: If generating a tag (branch), one should assign the revision number to the external link to truly snapshot the repository for that tag. This revision number should be specified in the tagged branch version of the svn external. [Potential Pitfall]: The revision numbers shown by svn info will reflect the version numbers of the repository in which the files are stored. If the files are imported via an svn external directory, the revision numbers will reflect that of the external repository which the external points to and thus from where the files were imported.

Command	Description
svn propdel PropertyName file-name svn propdel --revprop -r RevisionName http://url/path Also: pdel, pd	Remove property name from files or directories. Remove properties on file in repository.
svn propedit PropertyName file-name svn propedit --revprop -r RevisionName http://url/path Also: pedit, pe	Edit property name of files or directories. Edit properties on file in repository.
svn propget PropertyName file-name svn propget --revprop -r RevisionName http://url/path Also: pget, pg	Print value of property name of files or directories. Print properties on file in repository.
svn proplist file-name svn proplist * svn proplist --revprop -r RevisionName http://url/path Also: plist, pl	List properties of file, files or directory.
svn propset PROPNAME PropertyValue file-name svn propset PROPNAME --revprop -r RevisionName PropertyValue http://url/path svn propset svn:mime-type text/html file-name.dat Also: pset, ps	Set properties of file or directory. Set mime type for a file in the repository. Must perform a commit to upload changes to the repository. Set file properties so that "^M"'s are removed upon check-in: svn propset svn:eol-style LF file-name.txt See YoLinux Subversion server configuration tutorial: No ctrl-M.

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Subversion and Graphical diffs for Linux:

Three types of file differences are covered in this section:

1. Show file differences made since checkout was made. This shows the changes you have made. It is usefull to perform this before an update.
2. Show file differences between two files versions stored in Subversion.
3. Show differences / conflicts, choose and merge. Use our bash script svndiffwrapper which integrates into Subversion's file check-in process.

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1) File differences since checkout:

The following scripts will allow you to view the changes you have made since checkout. Use the script before running "svn update" as an update will alter the file with diff chevron (>>>>) markers. After performing a "svn update", use tkdiff, gtkdiff or kdiff3 as described below instead of the scripts:
Use the following bash shell script to use the graphical diff tool "mgdiff" with Subversion.

svndiff:

01 #!/bin/bash 02 # svndiff 1.0 03 # usage: svndiff file 04   05 if [[ ! -d .svn ]] 06 then 07    echo ERROR: You are not working in an SVN directory. 08    exit 1 09 fi 10   11 rev="--revision HEAD" 12   13 if [[ ! -n $1 ]] 14 then 15    echo "Usage: svndiff [option] file" 16    echo "Options:" 17    echo "  -h         Diff with latest in repository (HEAD) - Default" 18    echo "  -b         Diff with what you had checked out (BASE)" 19    echo "  -c         Diff with COMMITTED, the version before BASE" 20    echo "  -p         Diff with PREV, the version before COMMITTED" 21    echo "  -r revnum  Diff with specified revision (specify integer)" 22    exit 1 23 fi 24   25 while getopts ":r:hbcp" Option 26 do 27    case $Option in 28      h) rev="--revision HEAD";; 29      b) rev="--revision BASE";; 30      c) rev="--revision COMMITTED";; 31      p) rev="--revision PREV";; 32      r) rev="--revision $OPTARG";; 33      *) echo "Incorrect option specified. Use -h or -b or -r #";; 34     esac 35 done 36 shift $(($OPTIND -1)) 37   38 # Define graphical diff tool 39 # 40   41 # The geometry option used by Motif, Tcl and X based programs 42 geometry="-geometry 1280x800+0+0" 43   44 # The following is for Motif diff 45 # -w: ignore white space 46 dif="mgdiff -args -w" 47   48 file=$1 49 prev=${file}_PREV 50   51 # Trap bash command signals 52 # SIGINT   2 53 # SIGQUIT  3 54 # SIGTERM 15 55 trap "rm -f $prev" 2 3 15 56 svn cat $rev $file > $prev 2>/dev/null 57 $dif $geometry $prev $file 58   59 sleep 1 60 rm -f $prev

Compares your current local copy with the latest in the repository (Default "-h").

OR
Use the following bash shell script to use the graphical diff tool "gvimdiff:" with Subversion:

svndiff:

01 #!/bin/bash 02 # usage: svndiff file 03   04 if [[ ! -d .svn ]] 05 then 06    echo ERROR: You are not working in an SVN directory. 07    exit 1 08 fi 09   10 # Define graphical diff tool 11 # 12   13 dif="gvimdiff \"+colo morning\" -R" 14   15 file=$1 16 prev=PREV_${file} 17   18 # Trap bash command signals 19 # SIGINT   2 20 # SIGQUIT  3 21 # SIGTERM 15 22 trap "rm -f $prev" 2 3 15 23 svn cat $file > $prev 2>/dev/null 24 $dif $prev $file 25   26 # Sleep for non-blocking apps like gvimdiff. 27 # Allow gvimdiff to read file before it is deleted. 28 sleep 2 29 rm -f $prev

Compare your current local copy with the original copy you checked out.

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2) File differences between two revisions:

This configuration supports the use of GUI diff tools with Subversion by using the command: svn diff -r 457:459 --diff-cmd
Some diff tools are supported with native svn. i.e.: svn diff -r 457:459 --diff-cmd kdiff3 file-name while others require a wrapper script to arrange the arguments correctly.
Subversion configurations and defaults are specified in the file: $HOME/.subversion/config

.. ... [helpers] editor-cmd = gedit diff-cmd = /opt/bin/diffScript diff3-cmd = /opt/bin/diff3Script ... ..

This configuration configures Subversion to execute the script /opt/bin/diffScript to launch your own diff toolwith the command: svn diff -r Old:New URL.
File: /opt/bin/diffScript

01 #!/bin/bash 02   03 LeftLabel=$3 04 RightLabel=$5 05 LeftFile=$6 06 RightFile=$7 07   08 #gtkdiff $LeftFile $RightFile 09 tkdiff $LeftFile $RightFile -L "$LeftLabel" -L "$RightLabel" & 10   11 # wait for command to finish 12 wait

Note: To debug what is passed as a command line argument to the diff tool, set the diff-cmd to "echo":

.. ... [helpers] diff-cmd = echo ... ..

This configuration echos to the screen the command line arguments being passed to the diff tool when the following command is executed: svn diff ..... i.e. -u -L d0/f01.cpp (revision 1) -L d0/f01.cpp (working copy) d0/.svn/text-base/f01.cpp.svn-base d0/.svn/empty-file

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3) Conflicts, file differences and merge:

• tkdiff: Subversion conflict resolution merge: tkdiff -conflict file1.cpp
  Select from tkdiff toolbar: "Merge" + "Show Merge Window" to open third results window.
  
• kdiff3 diff and merge: svn diff -r 457:459 --diff-cmd kdiff3 --extensions '-m' file-name
  
• svndiffwrapper: Bash script to add options to Merge|Ignore|Accept|Revert etc as a result of a check-in. This script does it all!!

  Edit file: $HOME/.subversion/config

  ... [helpers] diff-cmd = svndiffwrapper diff3-cmd = svndiffwrapper ...

  Use our bash script svndiffwrapper to perform this integrated task. By default, uses kdiff3 for diff tool. Can also specify your own choice of diff tool.
  Place the script in /opt/bin/ for global use or $HOME/bin/ for private user access and set permissions so that script execution is allowed: chmod ugo+x /opt/bin/svndiffwrapper

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List of graphical diff and merge tools:

• tkdiff: [download] Comes with tkcvs Subversion GUI front-end.
  Examples of Subversion diffs with tkdiff: (See: tkdiff --help)
  • tkdiff old-URL@revA new-URL@revB
  • tkdiff -r457 -r459 file-name
  Note: Use command "svn log file-name" to view valid revision numbers for the file. Referencing invalid revision numbers as input to tkdiff will not work.
• gtkdiff: Has diff3 and merge features. Written with GTK+. After gtkdiff-0.8.0, GNOME desktop required.
• diffUse: Diff/merge GUI tool. Good line matching features. Supports Unicode.
• kdiff3: Graphical directory and file diff, merge and edit. KDE3/Qt based. Supports drag and drop. Comes with S.u.S.E. distro. (Cross platform) MS/Windows download available. A very good directory and file diff and merge tool.
  • Difference: kdiff3 file1 file2
  • Difference: kdiff3 file1 file2 file3
  • Difference of two files: kdiff3 directory1/file directory2
  • Difference: kdiff3 directory1 directory2
  • Merge: kdiff3 directory1 directory2 -o dest-directory
  • Merge: kdiff3 file1 file2 -m
  • Merge: kdiff3 file1 file2 -o output-file
  • Diff with SVN: svn diff -r 457:459 --diff-cmd kdiff3 file-name
• Kompare: Ships with (RHEL5/RHEL4/FC3+) KDE SDK. [manual]
  Included in RPM package "kdesdk".
  [Potential Pitfall]: RPM installation error:

  error: Failed dependencies:
          perl(DCOP) is needed by kdesdk-3.5.4-3.el5.i386 

  Solution: Install the dependency package "kdebindings".
• mgdiff: [download] Motif-based graphical file difference browser and merge. Comes with S.u.S.E. distro.
• Meld: Compare, edit and merge.
• fldiff: Graphical file and directory diff. (Cross platform)
• xxdiff: Compare 2 or 3 files and merge. Also compares directories.
• gvim and gvimdiff
• Beyond Compare - commercial tool (cross platform)

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Subversion GUI interfaces for Linux:

• TkSVN / TkCVS: Tcl/Tk based GUI. A very good Unix/Linux and MS/Windows GUI front-end to Subversion. Simple to install (requires tk). Supports GUI diff/merge, branching, tagging, editing, check-in/check-out, ...
  Installation to /usr/local/bin and lib (Add to your path.): (requires RPM: tk version 8.4+)
  • tar xzf tkcvs_8_0_3.tar.gz
  • cd tkcvs_8_0_3
  • ./doinstall.tcl -nox /opt
  Configuration: (See: ~/.tkcvs)

  Set default editor and diff tool:

  ... set cvscfg(editor) "xterm -e vim" set cvscfg(tkdiff) "tkdiff"

  Also see default config file: /opt/lib/tkcvs/tkcvs_def.tcl
  Sets default editors for various file types. Set editor to "gedit" for rookies.

  If you want to run TkSVN / TkCVS on MS/Windows, download Tk for MS/Windows. It can also be run from the Cygwin environment using Tk provided in the Cygwin shell.
• Tigris.org: RapidSVN: Dependent on wxWidgets cross platform C++ GUI API.
  Download RPMs from RpmForge.org:
  • rapidsvn-0.7.2-1.2.el4.rf.i386.rpm
  • wxGTK-2.4.2-5.2.el4.rf.i386.rpm
• pysvn: Python subversion front-end. (cross platform) [download]
• eSVN: qt based GUI. Mediocre.
• KdeSvn: KDE front-end.
• Subcommander: Subversion GUI client with visual diff and merge tool with support for different text encodings
• Subview: GTK based subversion (1.3+) client.
• JSVN: Java SVN client
• Syncro SVN Client - Commercial product. Editor, diff tool and SVN client in one integrated tool.

Web Clients:

• Kamikaze-qscm: Web based front-end similar to Mozilla Bonsai.
• WebClient for SVN: Implemented in JSP for Tomcat 4
• ViewSVN: PHP4
• Easy SVN: PERL cgi

Plug-ins:

• Rabbitvcs: GNOME Nautilus file browser SVN plug-in. Google code project to develop TortoiseSVN clone in Linux Nautilus file manager. Best prospect for my next favorite SVN client. Will also support other Gnome applications.
  YoLinux RabbitVCS tutorial
• NaughtySVN: GNOME Nautilus file browser SVN plug-in.
• Ksvn: Subversion client plugin for the KDE Konqueror browser.
• Eclipse plug-ins:
  • Tigris.org: subclipse
    Also see: C/C++ development environment and Eclipse
  • Subversive

Note: A Subversion client is built into many of today's development IDEs such as NetBeans. Comparison chart of Subversion clients

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Subversion Security Tips:

One should be aware of a possible Subversion client security hole. The Subversion client authentication will cache your login and password in your home directory in non-encrypted clear text. It will have file system security so others can not read the file however, it still is visible by root or by a root user of the file server if one is used for home directories.
Here are three solutions to reduce this potential security vulnerability:

1. Don't allow Subversion to cache the password: svn commit -F file.txt --no-auth-cache
   This will request a username and password but will not store it.
2. Set the Subversion configuration file on server to not cache:

   [auth] store-auth-creds = no

3. Delete cached files when you logout. Reduces risk but does not eliminate it. This uses the bash shell logout script to perform a clean-up of the authentication files.

   File: ~/.bash_logout

   1 rm ~/.subversion/auth/svn.simple/*

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Subversion utility commands and scripts:

Command	Description
svnversion local-path	This svn admin command will produce a compact version number for a working copy. Lists range of versions, adds "S" if switched, "M" modified.
svnchangesince	Shows the changes to the subversion repository since the local copy was last updated.
svnlastlog	Displays the last log message that pertains to the current working copy. Simplified svnlastchange.
svnlastchange	Displays the last log message and a unified diff of the changes made in the last commit.
svn-clean	Removes all the files and directories that are not in Subversion.

List of KDE scripts (See scripts which start with "svn")

Get 4 position bound a position

Get 4 position bound a position
/**
     * @author phuc.duong
     * @todo G
     */
   public function getFourPosition($long, $lat, $distance) {
        $earthRadius = 6371;
        //latitude in radians
        $lat = ($lat * pi()) / 180;

        //longitude in radians
        $lon = ($long * pi()) / 180;

        //angular distance covered on earth's surface
        $d = floatval($distance) / $earthRadius;
        $arrTemp = array();
        $bearing = array(0, 90, 180, 270);
        foreach ($bearing as $key => $value) {
            $bearing = $value * pi() / 180; //rad
            $arrTemp[$key]['Lat'] = asin(sin($lat) * cos($d) + cos($lat) * sin($d) * cos($bearing));
            $arrTemp[$key]['Long'] = (($lon + atan2(sin($bearing) * sin($d) * cos($lat), cos($d) - sin($lat) * sin($arrTemp[$key]['Lat']))) * 180) / pi();
            $arrTemp[$key]['Lat'] = ($arrTemp[$key]['Lat'] * 180) / pi();
        }
        return $arrTemp;
    }

Get Latitude/Longitude from an address (or Geocoding ) using PHP

$geocode=file_get_contents('http://maps.google.com/maps/api/

geocode/json?address=573/1,+Jangli+Maharaj+Road,

+Deccan+Gymkhana,+Pune,+Maharashtra,+India&sensor=false');

$output= json_decode($geocode);

$lat = $output->results[0]->geometry->location->lat;
$long = $output->results[0]->geometry->location->lng;