Allow parser from any reachable module

2 files changed, 15 insertions, 3 deletions

diff --git a/README.md b/README.md
index af1f8ea..572e169 100644
--- a/README.md
+++ b/README.md
@@ -63,6 +63,14 @@ to either Ganglia or Graphite.
 
     $ sudo /usr/sbin/logster --dry-run --output=graphite --graphite-host=graphite.example.com:2003 SampleLogster /var/log/httpd/access_log
 
+You can use the provided parsers, or you can use your own parsers by passing
+the complete module and parser name. In this case, the name of the parser does
+not have to match the name of the module (you can have a logster.py file with a
+MyCustomParser parser). Just make sure the module is in your Python path - via
+a virtualenv, for example.
+
+    $ /env/my_org/bin/logster --dry-run --output=stdout my_org_package.logster.MyCustomParser /var/log/my_custom_log
+
 Additional usage details can be found with the -h option:
 
     $ ./logster -h
diff --git a/bin/logster b/bin/logster
index bd77b43..12edb38 100755
--- a/bin/logster
+++ b/bin/logster
@@ -112,6 +112,9 @@ if 'graphite' in options.output and not options.graphite_host:
     cmdline.error("You must supply --graphite-host when using 'graphite' as an output type.")
 
 class_name = arguments[0]
+if class_name.find('.') == -1:
+    # If it's a single name, find it in the base logster package
+    class_name = 'logster.parsers.%s.%s' % (class_name, class_name)
 log_file   = arguments[1]
 state_dir  = options.state_dir
 logtail    = options.logtail
@@ -251,9 +254,10 @@ def main():
     logger.info("Executing parser %s on logfile %s" % (class_name, log_file))
     logger.debug("Using state file %s" % logtail_state_file)
 
-    # Import and instantiate the class from the module passed in.  Files and Class names must be the same.
-    module = __import__('logster.parsers.' + class_name, globals(), locals(), [class_name])
-    parser = getattr(module, class_name)(option_string=options.parser_options)
+    # Import and instantiate the class from the module passed in.
+    module_name, parser_name = class_name.rsplit('.', 1)
+    module = __import__(module_name, globals(), locals(), [parser_name])
+    parser = getattr(module, parser_name)(option_string=options.parser_options)
 
     # Check for lock file so we don't run multiple copies of the same parser 
     # simultaneuosly. This will happen if the log parsing takes more time than