switch from Step.run() recursion to Step.run()-in-a-loop to avoid too-deep call stacks

TODO.md

@@ -2,5 +2,4 @@
 
 * Improve documentation, especially on the contents of `pyruse.json`.
 * Maybe switch from storing the daily journal in a file, to storing it in a database.
-* Maybe switch from Step.run() recursion to Step.run()-in-a-loop to avoid too-deep call stacks.
 * Eventually make the code more elegant, as I learn more about Python…

pyruse/base.py

@@ -36,8 +36,7 @@ class Filter(Step):
         except Exception as e:
             nextStep = self.altStep
             log.error("Error while executing %s: %s." % (type(self), str(e)))
-        if nextStep:
+        return nextStep
-            nextStep.run(entry)
 
 class Action(Step):
     def __init__(self):
@@ -54,5 +53,4 @@ class Action(Step):
         except Exception as e:
             nextStep = None
             log.error("Error while executing %s: %s." % (type(self), str(e)))
-        if nextStep:
+        return nextStep
-            nextStep.run(entry)

pyruse/main.py

@@ -17,7 +17,7 @@ def _setPyrusePaths():
             sys.path.insert(1, p)
     PYRUSE_PATHS.insert(0, os.curdir)
 
-def _doForEachJournalEntry(fct):
+def _doForEachJournalEntry(workflow):
     j = journal.Reader(journal.SYSTEM_ONLY)
     j.seek_tail()
     j.get_previous()
@@ -25,7 +25,9 @@ def _doForEachJournalEntry(fct):
         event = j.wait(None)
         if event == journal.APPEND:
             for entry in j:
-                fct(entry)
+                step = workflow.firstStep
+                while step is not None:
+                    step = step.run(entry)
 
 def boot(modName):
     if "action_" in modName:
@@ -39,7 +41,7 @@ def main():
     _setPyrusePaths()
     conf = config.Config(PYRUSE_PATHS).asMap().get("actions", {})
     wf = workflow.Workflow(conf)
-    _doForEachJournalEntry(wf.run)
+    _doForEachJournalEntry(wf)
 
 if __name__ == '__main__':
     main()

pyruse/workflow.py

@@ -18,10 +18,7 @@ class Workflow:
                     for setter in dangling:
                         setter(entryPoint)
                 dangling = newDangling
-        self.run = firstStep.run if firstStep else self._noRun
+        self.firstStep = firstStep
-
-    def _noRun(self, whatever):
-        pass
 
     def _initChain(self, actions, label, seen):
         dangling = []

tests/main.py

@@ -53,9 +53,9 @@ def main():
     ]
     _clean()
     for e in test:
-        wf.run(e)
+        run(wf, e)
     actions.action_dailyReport.Action._hour = 25
-    wf.run(entry("bck", "login", "Failed password for root from ::1", 11))
+    run(wf, entry("bck", "login", "Failed password for root from ::1", 11))
     for f in ['acted_on.log', 'email.dump', 'nftBan.cmd', 'unfiltered.log']:
         assert os.path.exists(f), "file should exist: " + f
         try:
@@ -83,5 +83,10 @@ def entry(host, service, message, microsecond = None):
         "MESSAGE": message
     }
 
+def run(workflow, logEntry):
+    step = workflow.firstStep
+    while step is not None:
+        step = step.run(logEntry)
+
 if __name__ == '__main__':
     main()