Implement dump command.

src/zc/buildout/buildout.py

@@ -39,6 +39,7 @@ import distutils.errors
 import errno
 import glob
 import itertools
+import json
 import logging
 import os
 import pkg_resources
@@ -916,6 +917,19 @@ class Buildout(DictMixin):
                 self._logger.warning(
                     "Unexpected entry, %r, in develop-eggs directory.", f)
 
+    def _dump(self):
+        d = {}
+        for section, data in sorted(self._annotated.items()):
+            for k, v in sorted(data.items()):
+                if section == 'buildout' and k == 'directory':
+                    continue
+                elif v[1] == 'DEFAULT_VALUE':
+                    continue
+                elif k == '_profile_base_location_':
+                    continue
+                d.setdefault(section, {}).update({k: v[0]})
+        return json.dumps(d, sort_keys=True, indent=2)
+
     def _compute_part_signatures(self, parts):
         # Compute recipe signature and add to options
         for part in parts:
@@ -1260,6 +1274,9 @@ class Buildout(DictMixin):
     def annotate(self, args=None):
         _print_annotate(self._annotated)
 
+    def dump(self, args=None):
+        print_(self._dump())
+
     def print_options(self):
         for section in sorted(self._data):
             if section == 'buildout' or section == self['buildout']['versions']:
@@ -2098,6 +2115,11 @@ Commands:
     sorted alphabetically, along with the origin of the value (file name or
     COMPUTED_VALUE, DEFAULT_VALUE, COMMAND_LINE_VALUE).
 
+  dump
+
+    Display sections without buildout:directory and default values in
+    JSON format.
+
 """
 
 def _help():
@@ -2198,7 +2220,7 @@ def main(args=None):
         command = args.pop(0)
         if command not in (
             'install', 'bootstrap', 'runsetup', 'setup', 'init',
-            'annotate',
+            'annotate', 'dump',
             ):
             _error('invalid command:', command)
     else: