Merge pull request #266 from lekang9/master

Update publish_with_cache_flush in common.py

pubtools/_pulp/step.py

@@ -4,13 +4,16 @@
 from more_executors.futures import f_sequence, f_return
 
 LOG = logging.getLogger("pubtools.pulp")
+UNSET = object()
 
 
 class StepDecorator(object):
     """Implementation of PulpTask.step decorator. See that method for more info."""
 
-    def __init__(self, name):
+    def __init__(self, name, depends_on, skipped_value):
         self._name = name
+        self._depends_on = depends_on or []
+        self._skipped_value = skipped_value
 
     @property
     def human_name(self):
@@ -28,7 +31,11 @@ def new_fn(instance, *args, **kwargs):
                     self.human_name,
                     extra={"event": {"type": "%s-skip" % self.machine_name}},
                 )
-                return args[0] if args else None
+                return (
+                    self._skipped_value
+                    if self._skipped_value is not UNSET
+                    else args[0] if args else None
+                )
 
             logger = StepLogger(self)
             args = logger.log_start(args)
@@ -53,7 +60,8 @@ def new_fn(instance, *args, **kwargs):
 
     def should_skip(self, instance):
         skip = (getattr(instance.args, "skip", None) or "").split(",")
-        return self.machine_name in skip
+        deps_and_self = self._depends_on + [self.machine_name]
+        return any([name in skip for name in deps_and_self])
 
 
 # helpers used in implementation of decorator

pubtools/_pulp/task.py

@@ -4,7 +4,7 @@
 
 from pubtools.pluggy import task_context
 
-from .step import StepDecorator
+from .step import StepDecorator, UNSET
 
 
 LOG = logging.getLogger("pubtools.pulp")
@@ -68,13 +68,17 @@ def args(self):
         return self._args
 
     @classmethod
-    def step(cls, name):
+    def step(cls, name, depends_on=None, skipped_value=UNSET):
         """A decorator to mark an instance method as a discrete workflow step.
 
         Marking a method as a step has effects:
 
         - Log messages will be produced when entering and leaving the method
         - The method can be skipped if requested by the caller (via --skip argument)
+        - Methods that depend on other methods are implicitly skipped if depends_on
+          is supplied and that dependant is being skipped
+        - If the method is skipped, it returns either `skipped_value` (if that has
+          been set), or the method's first argument.
 
         Steps may be written as plain blocking functions, as non-blocking
         functions which accept or return Futures, or as generators.
@@ -94,7 +98,7 @@ def step(cls, name):
         - The step is considered *failed* if it raised an exception.
         - The step is considered *finished* once all items have been yielded.
         """
-        return StepDecorator(name)
+        return StepDecorator(name, depends_on, skipped_value)
 
     def _basic_args(self):
         # minimum args required for a pulp CLI task

pubtools/_pulp/tasks/common.py

@@ -36,7 +36,7 @@
 class CDNCache(FastPurgeClientService, CdnClientService):
     """Provide features to interact with CDN cache."""
 
-    @step("Flush CDN cache")
+    @step("Flush CDN cache", depends_on=["publish"], skipped_value=[])
     def flush_cdn(self, repos):
         """Clears the CDN cache for the repositories provided
 

tests/logs/clear_repo/test_clear_repo/test_clear_file_skip_publish.jsonl

@@ -7,5 +7,4 @@
 {"event": {"type": "publish-skip"}}
 {"event": {"type": "flush-ud-cache-start"}}
 {"event": {"type": "flush-ud-cache-end"}}
-{"event": {"type": "flush-cdn-cache-start"}}
-{"event": {"type": "flush-cdn-cache-end"}}
+{"event": {"type": "flush-cdn-cache-skip"}}

tests/logs/clear_repo/test_clear_repo/test_clear_file_skip_publish.txt

@@ -9,6 +9,4 @@
 [    INFO] Flush UD cache: started
 [    INFO] UD cache flush is not enabled.
 [    INFO] Flush UD cache: finished
-[    INFO] Flush CDN cache: started
-[    INFO] CDN cache flush is not enabled.
-[    INFO] Flush CDN cache: finished
+[    INFO] Flush CDN cache: skipped