Migration from Subversion to Mercurial

1. Migration
from
Subversion to Mercurial
Ladislav Prskavec
http://blog.prskavec.net
ladislav.prskavec@gmail.com
OpenMeeting 27.9.2009

2. Why Mercurial ?
Bitbucket.org (php-frameworks.net)
Google Code (php4hudson, phpchangelogs)
Keywords (phpdoc, git not support)
Revisions (git not support)
Netbeans (native support)
Eclipse plugin (Zend Studio)
http://www.vectrace.com/mercurialeclipse/
Many extensions
Negatives
partial rebase (extension)
experimental subrepos in Mercurial 1.3.1 (svn:externals)

3. Why Mercurial ?
Bitbucket.org (private rep, issues)

4. SVN xml logs to Hg
Question: How make svn log --xml
Answer: hglog.sh
echo '<?xml version="1.0"?>n<log>n' >$1.xml
hg log --template '<logentry revision="{rev}">
<author>{author|obfuscate}</author>
<date>{date|isodate}</date>
<msg>{desc|escape}n</msg>
<paths><path>{files}</path></paths>
</logentry>n' $1/ >>$1.xml
echo '</log>n' >>$1.xml

5. RCS keywords
Question: How make keywords?
Answer: Keywords extension (part from .hgrc)
[extensions]
hgext.keyword =
keyword=/usr/share/python-support/mercurial-common/hgext/keyword.py
[keyword]
**.php =
**.xml =
[keywordmaps]
RCSFile = {file|basename},v
Author = {author|user}
Header = {root}/{file},v {node|short} {date|utcdate} {author|user}
Source = {root}/{file},v
Date = {date|utcdate}
Id = {file|basename},v {node|short} {date|utcdate} {author|user}
Revision = {node|short}

6. Deployment
SVN deployment script
svn --force export http://svn.rep.cz/svn/project/trunk/ /srv/www/project.cz/
/usr/bin/svn2cl --strip-prefix=trunk --break-before-msg=2 --group-by-day --separate-daylogs -i --
authors=/srv/www/project.cz/application/configs/authors.xml http://svn.rep.cz/svn/project/trunk -o /srv/www/project.
cz/changelog
sed -i 's/development/production/g' /srv/www/project.cz/public/.htaccess
chown -Rf www-data:www-data /srv/www/project.cz/
Mercurial deployment script
cd ~/hg-ws/project.cz/
hg pull
hg up
hg archive /srv/www/project.cz/
sed -i 's/development/production/g' /srv/www/project.cz/public/.htaccess
chown -Rf www-data:www-data /srv/www/project.cz/

7. Hooks scripts
Subversion (server, repos/hooks/pre-commit)
#!/bin/sh
REPOS="$1"
TXN="$2"
# check php
CHANGED=`svnlook changed -t "$TXN" "$REPOS" | awk '{print $2}' | grep .php$`
for FILE in $CHANGED
do
MESSAGE=`svnlook cat -t "$TXN" "$REPOS" "$FILE" | $PHP -l `
if [ $? -ne 0 ]
then
exit 1
fi
done
exit 0
Mercurial (in .hg/hgrc)
[hooks]
precommit = test `find -name *.php -exec php -l {} ; | wc -l` -eq 1

8. Summary
Evolution not revolution
Some workflow for my projects in Mercurial and Svn
Local commits
hg backout
hg rollback (working only localy)
Check extensions
http://mercurial.selenic.com/wiki/UsingExtensions
Convert (from others SCM: cvs, svn, git, darcs, bzr, arch, mnt)
Fetch
Keyword
Notify
Rebase
Record (staging area)

9. Thanks for your attention
http://slideshare.net/ladislavprskavec
Ladislav Prskavec
http://blog.prskavec.net
ladislav.prskavec@gmail.com