validating schema in discovery mode

Nick McCoy · Nick McCoy · commit 9cbdfa25bf48 · 2017-11-22T16:14:29.000-05:00
Added write_catalog function
diff --git a/singer/catalog.py b/singer/catalog.py
@@ -4,6 +4,7 @@
 import sys
 
 from singer.schema import Schema
+from jsonschema import ValidationError, Draft4Validator, FormatChecker
 
 # pylint: disable=too-many-instance-attributes
 class CatalogEntry(object):
@@ -109,3 +110,29 @@ def get_stream(self, tap_stream_id):
             if stream.tap_stream_id == tap_stream_id:
                 return stream
         return None
+
+
+CATALOG_SCHEMA = {'type': 'object',
+                  'required': ['streams'],
+                  'properties': {
+                      'streams' : {
+                          'type': 'array',
+                          'items': {
+                              'type': 'object',
+                              'required': ['stream', 'tap_stream_id', 'schema'],
+                              'properties': {
+                                  'stream': {'type': 'string'},
+                                  'tap_stream_id': {'type': 'string'},
+                                  'schema': {'type': 'object'}
+                              }
+                          }
+                      }
+                  }
+              }
+
+CATALOG_VALIDATOR = Draft4Validator(CATALOG_SCHEMA,
+                                    format_checker=FormatChecker())
+
+def write_catalog(streams):
+    CATALOG_VALIDATOR.validate(streams)
+    json.dump(streams, sys.stdout, indent=2)
diff --git a/tests/test_catalog.py b/tests/test_catalog.py
@@ -1,11 +1,10 @@
 import unittest
+import singer.catalog 
 
 from singer.schema import Schema
 from singer.catalog import Catalog, CatalogEntry
 
-class TestToDictAndFromDict(unittest.TestCase):
-
-    dict_form = {
+dict_form = {
         'streams': [
             {
                 'stream': 'users',
@@ -38,7 +37,7 @@ class TestToDictAndFromDict(unittest.TestCase):
             ]
         }
 
-    obj_form = Catalog(streams=[
+obj_form = Catalog(streams=[
         CatalogEntry(
             stream='users',
             tap_stream_id='prod_users',
@@ -62,11 +61,15 @@ class TestToDictAndFromDict(unittest.TestCase):
                     'id': Schema(type='integer', selected=True),
                     'amount': Schema(type='number', selected=True)}))])
 
+
+
+
+class TestToDictAndFromDict(unittest.TestCase):
     def test_from_dict(self):
-        self.assertEqual(self.obj_form, Catalog.from_dict(self.dict_form))
+        self.assertEqual(obj_form, Catalog.from_dict(dict_form))
 
     def test_to_dict(self):
-        self.assertEqual(self.dict_form, self.obj_form.to_dict())
+        self.assertEqual(dict_form, obj_form.to_dict())
         
 
 class TestGetStream(unittest.TestCase):
@@ -77,3 +80,7 @@ def test(self):
              CatalogEntry(tap_stream_id='c')])
         entry = catalog.get_stream('b')
         self.assertEquals('b', entry.tap_stream_id)
+
+class TestWriteCatalog(unittest.TestCase):
+    def test(self):
+        singer.catalog.write_catalog(dict_form)
