master/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
  21 import sys
  22 import commands
  23 import xml
  24
  25 from buildbot.clients import sendchange
  26 from twisted.internet import defer, reactor
  27 from xml.dom import minidom
  28
  29
  30 def getText(node):
  31     return "".join([cn.data
  32                     for cn in node.childNodes
  33                     if cn.nodeType == cn.TEXT_NODE])
  34
  35
  36 def getTextFromChild(parent, childtype):
  37     children = parent.getElementsByTagName(childtype)
  38     if not children:
  39         return ""
  40     return getText(children[0])
  41
  42
  43 def makeChange(p):
  44     author = p.getAttribute("author")
  45     revision = p.getAttribute("hash")
  46     comments = (getTextFromChild(p, "name") + "\n" +
  47                 getTextFromChild(p, "comment"))
  48
  49     summary = p.getElementsByTagName("summary")[0]
  50     files = []
  51     for filenode in summary.childNodes:
  52         if filenode.nodeName in ("add_file", "modify_file", "remove_file"):
  53             filename = getText(filenode).strip()
  54             files.append(filename)
  55         elif filenode.nodeName == "move":
  56             from_name = filenode.getAttribute("from")
  57             to_name = filenode.getAttribute("to")
  58             files.append(to_name)
  59
  60     # note that these are all unicode. Because PB can't handle unicode, we
  61     # encode them into ascii, which will blow up early if there's anything we
  62     # can't get to the far side. When we move to something that *can* handle
  63     # unicode (like newpb), remove this.
  64     author = author.encode("ascii", "replace")
  65     comments = comments.encode("ascii", "replace")
  66     files = [f.encode("ascii", "replace") for f in files]
  67     revision = revision.encode("ascii", "replace")
  68
  69     change = {
  70         # note: this is more likely to be a full email address, which would
  71         # make the left-hand "Changes" column kind of wide. The buildmaster
  72         # should probably be improved to display an abbreviation of the
  73         # username.
  74         'username': author,
  75         'revision': revision,
  76         'comments': comments,
  77         'files': files,
  78         }
  79     return change
  80
  81
  82 def getChangesFromCommand(cmd, count):
  83     out = commands.getoutput(cmd)
  84     try:
  85         doc = minidom.parseString(out)
  86     except xml.parsers.expat.ExpatError, e:
  87         print "failed to parse XML"
  88         print str(e)
  89         print "purported XML is:"
  90         print "--BEGIN--"
  91         print out
  92         print "--END--"
  93         sys.exit(1)
  94
  95     c = doc.getElementsByTagName("changelog")[0]
  96     changes = []
  97     for i, p in enumerate(c.getElementsByTagName("patch")):
  98         if i >= count:
  99             break
 100         changes.append(makeChange(p))
 101     return changes
 102
 103
 104 def getSomeChanges(count):
 105     cmd = "darcs changes --last=%d --xml-output --summary" % count
 106     return getChangesFromCommand(cmd, count)
 107
 108
 109 LASTCHANGEFILE = ".darcs_buildbot-lastchange"
 110
 111
 112 def findNewChanges():
 113     if os.path.exists(LASTCHANGEFILE):
 114         f = open(LASTCHANGEFILE, "r")
 115         lastchange = f.read()
 116         f.close()
 117     else:
 118         return getSomeChanges(1)
 119     lookback = 10
 120     while True:
 121         changes = getSomeChanges(lookback)
 122         # getSomeChanges returns newest-first, so changes[0] is the newest.
 123         # we want to scan the newest first until we find the changes we sent
 124         # last time, then deliver everything newer than that (and send them
 125         # oldest-first).
 126         for i, c in enumerate(changes):
 127             if c['revision'] == lastchange:
 128                 newchanges = changes[:i]
 129                 newchanges.reverse()
 130                 return newchanges
 131         if 2*lookback > 100:
 132             raise RuntimeError("unable to find our most recent change "
 133                                "(%s) in the last %d changes" % (lastchange,
 134                                                                 lookback))
 135         lookback = 2*lookback
 136
 137
 138 def sendChanges(master):
 139     changes = findNewChanges()
 140     s = sendchange.Sender(master)
 141
 142     d = defer.Deferred()
 143     reactor.callLater(0, d.callback, None)
 144
 145     if not changes:
 146         print "darcs_buildbot.py: weird, no changes to send"
 147         return
 148     elif len(changes) == 1:
 149         print "sending 1 change to buildmaster:"
 150     else:
 151         print "sending %d changes to buildmaster:" % len(changes)
 152
 153     # the Darcs Source class expects revision to be a context, not a
 154     # hash of a patch (which is what we have in c['revision']).  For
 155     # the moment, we send None for everything but the most recent, because getting
 156     # contexts is Hard.
 157
 158     # get the context for the most recent change
 159     latestcontext = commands.getoutput("darcs changes --context")
 160     changes[-1]['context'] = latestcontext
 161
 162     def _send(res, c):
 163         branch = None
 164         print " %s" % c['revision']
 165         return s.send(branch, c.get('context'), c['comments'], c['files'],
 166                       c['username'])
 167     for c in changes:
 168         d.addCallback(_send, c)
 169
 170     d.addCallbacks(s.printSuccess, s.printFailure)
 171     d.addBoth(s.stop)
 172     s.run()
 173
 174     if changes:
 175         lastchange = changes[-1]['revision']
 176         f = open(LASTCHANGEFILE, "w")
 177         f.write(lastchange)
 178         f.close()
 179
 180
 181 if __name__ == '__main__':
 182     MASTER = sys.argv[1]
 183     sendChanges(MASTER)