contrib/darcs_buildbot.py

   1 #! /usr/bin/python
   2
   3 # This is a script which delivers Change events from Darcs to the buildmaster
   4 # each time a patch is pushed into a repository. Add it to the 'apply' hook
   5 # on your canonical "central" repository, by putting something like the
   6 # following in the _darcs/prefs/defaults file of that repository:
   7 #
   8 #  apply posthook /PATH/TO/darcs_buildbot.py BUILDMASTER:PORT
   9 #  apply run-posthook
  10 #
  11 # (the second command is necessary to avoid the usual "do you really want to
  12 # run this hook" prompt. Note that you cannot have multiple 'apply posthook'
  13 # lines: if you need this, you must create a shell script to run all your
  14 # desired commands, then point the posthook at that shell script.)
  15 #
  16 # Note that both Buildbot and Darcs must be installed on the repository
  17 # machine. You will also need the Python/XML distribution installed (the
  18 # "python2.3-xml" package under debian).
  19
  20 import os, sys, commands
  21 from buildbot.clients import sendchange
  22 from twisted.internet import defer, reactor
  23 import xml
  24 from xml.dom import minidom
  25
  26 def getText(node):
  27     return "".join([cn.data
  28                     for cn in node.childNodes
  29                     if cn.nodeType == cn.TEXT_NODE])
  30 def getTextFromChild(parent, childtype):
  31     children = parent.getElementsByTagName(childtype)
  32     if not children:
  33         return ""
  34     return getText(children[0])
  35
  36 def makeChange(p):
  37
  38     author = p.getAttribute("author")
  39     revision = p.getAttribute("hash")
  40     comments = (getTextFromChild(p, "name") + "\n" +
  41                 getTextFromChild(p, "comment"))
  42
  43     summary = p.getElementsByTagName("summary")[0]
  44     files = []
  45     for filenode in summary.childNodes:
  46         if filenode.nodeName in ("add_file", "modify_file", "remove_file"):
  47             filename = getText(filenode).strip()
  48             files.append(filename)
  49         elif filenode.nodeName == "move":
  50             from_name = filenode.getAttribute("from")
  51             to_name = filenode.getAttribute("to")
  52             files.append(to_name)
  53
  54     # note that these are all unicode. Because PB can't handle unicode, we
  55     # encode them into ascii, which will blow up early if there's anything we
  56     # can't get to the far side. When we move to something that *can* handle
  57     # unicode (like newpb), remove this.
  58     author = author.encode("ascii")
  59     comments = comments.encode("ascii")
  60     files = [f.encode("ascii") for f in files]
  61     revision = revision.encode("ascii")
  62
  63     change = {
  64         # note: this is more likely to be a full email address, which would
  65         # make the left-hand "Changes" column kind of wide. The buildmaster
  66         # should probably be improved to display an abbreviation of the
  67         # username.
  68         'username': author,
  69         'revision': revision,
  70         'comments': comments,
  71         'files': files,
  72         }
  73     return change
  74
  75
  76
  77 def getChangesFromCommand(cmd, count):
  78     out = commands.getoutput(cmd)
  79     try:
  80         doc = minidom.parseString(out)
  81     except xml.parsers.expat.ExpatError, e:
  82         print "failed to parse XML"
  83         print str(e)
  84         print "purported XML is:"
  85         print "--BEGIN--"
  86         print out
  87         print "--END--"
  88         sys.exit(1)
  89
  90     c = doc.getElementsByTagName("changelog")[0]
  91     changes = []
  92     for i,p in enumerate(c.getElementsByTagName("patch")):
  93         if i >= count:
  94             break
  95         changes.append(makeChange(p))
  96     return changes
  97
  98 def getSomeChanges(count):
  99     cmd = "darcs changes --last=%d --xml-output --summary" % count
 100     return getChangesFromCommand(cmd, count)
 101
 102
 103 LASTCHANGEFILE = ".darcs_buildbot-lastchange"
 104
 105 def findNewChanges():
 106     if os.path.exists(LASTCHANGEFILE):
 107         f = open(LASTCHANGEFILE, "r")
 108         lastchange = f.read()
 109         f.close()
 110     else:
 111         return getSomeChanges(1)
 112     lookback = 10
 113     while True:
 114         changes = getSomeChanges(lookback)
 115         # getSomeChanges returns newest-first, so changes[0] is the newest.
 116         # we want to scan the newest first until we find the changes we sent
 117         # last time, then deliver everything newer than that (and send them
 118         # oldest-first).
 119         for i,c in enumerate(changes):
 120             if c['revision'] == lastchange:
 121                 newchanges = changes[:i]
 122                 newchanges.reverse()
 123                 return newchanges
 124         if 2*lookback > 100:
 125             raise RuntimeError("unable to find our most recent change "
 126                                "(%s) in the last %d changes" % (lastchange,
 127                                                                 lookback))
 128         lookback = 2*lookback
 129
 130 def sendChanges(master):
 131     changes = findNewChanges()
 132     s = sendchange.Sender(master, None)
 133
 134     d = defer.Deferred()
 135     reactor.callLater(0, d.callback, None)
 136
 137     if not changes:
 138         print "darcs_buildbot.py: weird, no changes to send"
 139     elif len(changes) == 1:
 140         print "sending 1 change to buildmaster:"
 141     else:
 142         print "sending %d changes to buildmaster:" % len(changes)
 143
 144     def _send(res, c):
 145         branch = None
 146         print " %s" % c['revision']
 147         return s.send(branch, c['revision'], c['comments'], c['files'],
 148                       c['username'])
 149     for c in changes:
 150         d.addCallback(_send, c)
 151
 152     d.addCallbacks(s.printSuccess, s.printFailure)
 153     d.addBoth(s.stop)
 154     s.run()
 155
 156     if changes:
 157         lastchange = changes[-1]['revision']
 158         f = open(LASTCHANGEFILE, "w")
 159         f.write(lastchange)
 160         f.close()
 161
 162 if __name__ == '__main__':
 163     MASTER = sys.argv[1]
 164     sendChanges(MASTER)