Make the main command boilerplate available to library users.

2 files changed, 57 insertions, 18 deletions

diff --git a/lesana/command.py b/lesana/command.py
index 407544a..85ed73b 100644
--- a/lesana/command.py
+++ b/lesana/command.py
@@ -1,3 +1,4 @@
+import argparse
 import logging
 import os
 import subprocess
@@ -58,9 +59,35 @@ def edit_file_in_external_editor(filepath):
         return True
 
 
-class Command:
-    help = ''
+def _get_first_docstring_line(obj):
+    try:
+        return obj.__doc__.split('\n')[1].strip()
+    except (AttributeError, IndexError):
+        return None
+
+
+class MainCommand:
+    commands = ()
+
+    def _main(self, args):
+        self.parser.print_help()
+
+    def main(self):
+        desc = _get_first_docstring_line(self)
+        self.parser = argparse.ArgumentParser(description=desc)
+        self.parser.set_defaults(func=self._main)
+        self.subparsers = self.parser.add_subparsers()
+        for name, sub in self.commands:
+            sub_help = _get_first_docstring_line(sub)
+            s_parser = self.subparsers.add_parser(name, help=sub_help)
+            for arg in sub.arguments:
+                s_parser.add_argument(*arg[0], **arg[1])
+            s_parser.set_defaults(func=sub._main)
+        self.args = self.parser.parse_args()
+        self.args.func(self.args)
 
+
+class Command:
     def __init__(self, collection_class=Collection, entry_class=Entry):
         self.collection_class = collection_class
         self.entry_class = entry_class
@@ -71,6 +98,9 @@ class Command:
 
 
 class New(Command):
+    """
+    Create a new entry
+    """
     arguments = [
         (
             ['--collection', '-c'],
@@ -100,6 +130,9 @@ class New(Command):
 
 
 class Edit(Command):
+    """
+    Edit a lesana entry
+    """
     arguments = [
         (
             ['--collection', '-c'],
@@ -136,6 +169,9 @@ class Edit(Command):
 
 
 class Show(Command):
+    """
+    Show a lesana entry
+    """
     arguments = [
         (
             ['--collection', '-c'],
@@ -169,6 +205,9 @@ class Show(Command):
 
 
 class Index(Command):
+    """
+    Index entries in a lesana collection
+    """
     arguments = [
         (
             ['--collection', '-c'],
@@ -195,6 +234,9 @@ class Index(Command):
 
 
 class Search(Command):
+    """
+    Search for entries
+    """
     arguments = [
         (
             ['--collection', '-c'],
@@ -252,6 +294,9 @@ class Search(Command):
 
 
 class Export(Command):
+    """
+    Export entries to a different collection
+    """
     arguments = [
         (
             ['--collection', '-c'],
@@ -292,6 +337,9 @@ class Export(Command):
 
 
 class Init(Command):
+    """
+    Initialize a lesana collection
+    """
     arguments = [
         (
             ['--collection', '-c'],
@@ -316,6 +364,9 @@ class Init(Command):
 
 
 class Remove(Command):
+    """
+    Remove an entry from a collection
+    """
     arguments = [
         (
             ['--collection', '-c'],
@@ -330,6 +381,9 @@ class Remove(Command):
 
 
 class Update(Command):
+    """
+    Update a field in multiple entries
+    """
     arguments = [
         (
             ['--collection', '-c'],
diff --git a/scripts/lesana b/scripts/lesana
index c8e6b7f..8e34179 100755
--- a/scripts/lesana
+++ b/scripts/lesana
@@ -8,7 +8,7 @@ import argparse
 import lesana.command
 
 
-class Lesana:
+class Lesana(lesana.command.MainCommand):
     """
     Manage collections
     """
@@ -25,21 +25,6 @@ class Lesana:
         ("rm", lesana.command.Remove()),
     )
 
-    def _main(self, args):
-        self.parser.print_help()
-
-    def main(self):
-        self.parser = argparse.ArgumentParser()
-        self.parser.set_defaults(func=self._main)
-        self.subparsers = self.parser.add_subparsers()
-        for name, sub in self.commands:
-            s_parser = self.subparsers.add_parser(name, help=sub.help)
-            for arg in sub.arguments:
-                s_parser.add_argument(*arg[0], **arg[1])
-            s_parser.set_defaults(func=sub._main)
-        self.args = self.parser.parse_args()
-        self.args.func(self.args)
-
 
 if __name__ == "__main__":
     Lesana().main()