bitbake: add option to write offline event log file

This patch adds a "-w/--write-log" option to bitbake
that writes an event log file for the current build.

The name of the file is passed as a parameter to the "-w"
argument. If the parameter is the empty string '', the file
name is generated in the form bitbake_eventlog_DATE.json,
where DATE is the current date and time, with second precision.

The "-w" option can also be supplied as the BBEVENTLOG
environment variable.

We add a script, toater-eventreplay, that reads an event
log file and loads the data into a Toaster database, creating
a build entry.

We modify the toasterui to fix minor issues with reading
events from an event log file.

Performance impact is undetectable under no-task executed builds.

(Bitbake rev: 1befb4a783bb7b7b387d4b5ee08830d9516f1ac2)

Signed-off-by: Alexandru DAMIAN <alexandru.damian@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/cooker.py

@@ -205,6 +205,75 @@ class BBCooker:
         self.data = self.databuilder.data
         self.data_hash = self.databuilder.data_hash
 
+
+        # we log all events to a file if so directed
+        if self.configuration.writeeventlog:
+            import json, pickle
+            DEFAULT_EVENTFILE = self.configuration.writeeventlog
+            class EventLogWriteHandler():
+
+                class EventWriter():
+                    def __init__(self, cooker):
+                        self.file_inited = None
+                        self.cooker = cooker
+                        self.event_queue = []
+
+                    def init_file(self):
+                        try:
+                            # delete the old log
+                            os.remove(DEFAULT_EVENTFILE)
+                        except:
+                            pass
+
+                        # write current configuration data
+                        with open(DEFAULT_EVENTFILE, "w") as f:
+                            f.write("%s\n" % json.dumps({ "allvariables" : self.cooker.getAllKeysWithFlags(["doc", "func"])}))
+
+                    def write_event(self, event):
+                        with open(DEFAULT_EVENTFILE, "a") as f:
+                            try:
+                                f.write("%s\n" % json.dumps({"class":event.__module__ + "." + event.__class__.__name__, "vars":json.dumps(pickle.dumps(event)) }))
+                            except Exception as e:
+                                import traceback
+                                print(e, traceback.format_exc(e))
+
+
+                    def send(self, event):
+                        event_class = event.__module__ + "." + event.__class__.__name__
+
+                        # init on bb.event.BuildStarted
+                        if self.file_inited is None:
+                            if  event_class == "bb.event.BuildStarted":
+                                self.init_file()
+                                self.file_inited = True
+
+                                # write pending events
+                                for e in self.event_queue:
+                                    self.write_event(e)
+
+                                # also write the current event
+                                self.write_event(event)
+
+                            else:
+                                # queue all events until the file is inited
+                                self.event_queue.append(event)
+
+                        else:
+                            # we have the file, just write the event
+                            self.write_event(event)
+
+                # set our handler's event processor
+                event = EventWriter(self)       # self is the cooker here
+
+
+            # set up cooker features for this mock UI handler
+
+            # we need to write the dependency tree in the log
+            self.featureset.setFeature(CookerFeatures.SEND_DEPENDS_TREE)
+            # register the log file writer as UI Handler
+            bb.event.register_UIHhandler(EventLogWriteHandler())
+
+
         #
         # Special updated configuration we use for firing events
         #
@@ -505,7 +574,7 @@ class BBCooker:
         taskdata, runlist, pkgs_to_build = self.buildTaskData(pkgs_to_build, task, False)
 
         return runlist, taskdata
-    
+
     ######## WARNING : this function requires cache_extra to be enabled ########
 
     def generateTaskDepTreeData(self, pkgs_to_build, task):
@@ -1550,10 +1619,10 @@ class CookerCollectFiles(object):
         for p in pkgfns:
             realfn, cls = bb.cache.Cache.virtualfn2realfn(p)
             priorities[p] = self.calc_bbfile_priority(realfn, matched)
- 
+
         # Don't show the warning if the BBFILE_PATTERN did match .bbappend files
         unmatched = set()
-        for _, _, regex, pri in self.bbfile_config_priorities:        
+        for _, _, regex, pri in self.bbfile_config_priorities:
             if not regex in matched:
                 unmatched.add(regex)