handlers: improve documentation

Add docstrings to part, londiste, qtable, qsplitter, vtable handlers.

4 files changed, 26 insertions, 5 deletions

diff --git a/python/londiste/handler.py b/python/londiste/handler.py
index 252bf2de..87a16b62 100644
--- a/python/londiste/handler.py
+++ b/python/londiste/handler.py
@@ -120,7 +120,12 @@ class BaseHandler:
         return True
 
 class TableHandler(BaseHandler):
-    """Default Londiste handler, inserts events into tables with plain SQL."""
+    """Default Londiste handler, inserts events into tables with plain SQL.
+    
+    Parameters:
+      encoding=ENC - Validate and fix incoming data from encoding.
+                     Only 'utf8' is supported at the moment.
+    """
     handler_name = 'londiste'
 
     sql_command = {
diff --git a/python/londiste/handlers/part.py b/python/londiste/handlers/part.py
index 6530d03d..8f0eb378 100644
--- a/python/londiste/handlers/part.py
+++ b/python/londiste/handlers/part.py
@@ -1,7 +1,10 @@
-"""Event filtering by hash.
+"""Event filtering by hash, for partitioned databases.
 
 Parameters:
-
+  key=COLUMN: column name to use for hashing
+  hashfunc=FUNCNAME: function to use for hashing. (default: partconf.get_hash_raw)
+  hashexpr=EXPR: full expression to use for hashing (deprecated)
+  encoding=ENC: validate and fix incoming data (only utf8 supported atm)
 
 On root node:
 * Hash of key field will be added to ev_extra3.
@@ -10,10 +13,12 @@ On root node:
         ev_extra3='hash='||partconf.get_hash_raw(key_column)
 
 On branch/leaf node:
-
 * On COPY time, the SELECT on provider side gets filtered by hash.
 * On replay time, the events gets filtered by looking at hash in ev_extra3.
 
+Local config:
+* Local hash value and mask are loaded from partconf.conf table.
+
 """
 
 import skytools
@@ -22,6 +27,7 @@ from londiste.handler import TableHandler
 __all__ = ['PartHandler']
 
 class PartHandler(TableHandler):
+    __doc__ = __doc__
     handler_name = 'part'
 
     DEFAULT_HASHFUNC = "partconf.get_hash_raw"
diff --git a/python/londiste/handlers/qtable.py b/python/londiste/handlers/qtable.py
index cd8cb03d..b93543e9 100644
--- a/python/londiste/handlers/qtable.py
+++ b/python/londiste/handlers/qtable.py
@@ -20,7 +20,11 @@ __all__ = ['QueueTableHandler', 'QueueSplitterHandler']
 
 
 class QueueTableHandler(BaseHandler):
-    """Queue table handler. Do nothing"""
+    """Queue table handler. Do nothing.
+    
+    Trigger: before-insert, skip trigger.
+    Event-processing: do nothing.
+    """
     handler_name = 'qtable'
 
     def add(self, trigger_arg_list):
@@ -37,6 +41,11 @@ class QueueTableHandler(BaseHandler):
         return False
 
 class QueueSplitterHandler(BaseHandler):
+    """Send events for one table to another queue.
+
+    Parameters:
+      queue=QUEUE   Queue name.
+    """
     handler_name = 'qsplitter'
 
     def __init__(self, table_name, args, dest_table):
diff --git a/python/londiste/handlers/vtable.py b/python/londiste/handlers/vtable.py
index 2f5fd551..19e5df0f 100644
--- a/python/londiste/handlers/vtable.py
+++ b/python/londiste/handlers/vtable.py
@@ -8,6 +8,7 @@ __all__ = ['VirtualTableHandler', 'FakeLocalHandler']
 class VirtualTableHandler(BaseHandler):
     """Virtual Table.
 
+    Hack to get local=t for a table, but without processing any events.
     """
     handler_name = 'vtable'