source: json: Add label to JSONSource

Signed-off-by: John Andersen <john.s.andersen@intel.com>

Author: sudharsana-kjl

CHANGELOG.md

@@ -28,6 +28,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   sources.
 - A temporary directory is used to replicate `mktemp -u` functionality so as to
   provide tests using a FileSource with a valid tempfile name.
+- Labels for JSON sources
 
 ## [0.2.1] - 2019-06-07
 ### Added

dffml/source/file.py

@@ -19,6 +19,7 @@
 
 class FileSourceConfig(BaseConfig, NamedTuple):
     filename: str
+    label: str = "unlabeled"
     readonly: bool = False
 
 
@@ -114,11 +115,15 @@ def args(cls, args, *above) -> Dict[str, Arg]:
             "readonly",
             Arg(type=bool, action="store_true", default=False),
         )
+        cls.config_set(
+            args, above, "label", Arg(type=str, default="unlabeled")
+        )
         return args
 
     @classmethod
     def config(cls, config, *above):
         return FileSourceConfig(
             filename=cls.config_get(config, above, "filename"),
             readonly=cls.config_get(config, above, "readonly"),
+            label=cls.config_get(config, above, "label"),
         )

dffml/source/json.py

@@ -17,16 +17,21 @@ class JSONSource(FileSource, MemorySource):
     stored in memory.
     """
 
+    def __init__(self, config):
+        super().__init__(config)
+        self.repos = {}
+
     async def load_fd(self, fd):
-        repos = json.load(fd)
+        self.repos = json.load(fd)
         self.mem = {
             src_url: Repo(src_url, data=data)
-            for src_url, data in repos.items()
+            for src_url, data in self.repos.get(self.config.label, {}).items()
         }
         LOGGER.debug("%r loaded %d records", self, len(self.mem))
 
     async def dump_fd(self, fd):
-        json.dump(
-            {repo.src_url: repo.dict() for repo in self.mem.values()}, fd
-        )
+        self.repos[self.config.label] = {
+            repo.src_url: repo.dict() for repo in self.mem.values()
+        }
+        json.dump(self.repos, fd)
         LOGGER.debug("%r saved %d records", self, len(self.mem))

tests/source/test_file.py

@@ -70,6 +70,10 @@ def test_args(self):
                                     ),
                                     "config": {},
                                 },
+                                "label": {
+                                    "arg": Arg(type=str, default="unlabeled"),
+                                    "config": {},
+                                },
                             },
                         }
                     },
@@ -82,19 +86,27 @@ def test_config_readonly_default(self):
             parse_unknown("--source-file-filename", "feedface")
         )
         self.assertEqual(config.filename, "feedface")
+        self.assertEqual(config.label, "unlabeled")
         self.assertFalse(config.readonly)
 
     def test_config_readonly_set(self):
         config = FileSource.config(
             parse_unknown(
-                "--source-file-filename", "feedface", "--source-file-readonly"
+                "--source-file-filename",
+                "feedface",
+                "--source-file-label",
+                "default-label",
+                "--source-file-readonly",
             )
         )
         self.assertEqual(config.filename, "feedface")
+        self.assertEqual(config.label, "default-label")
         self.assertTrue(config.readonly)
 
-    def config(self, filename, readonly=False):
-        return FileSourceConfig(filename=filename, readonly=readonly)
+    def config(self, filename, label="unlabeled", readonly=False):
+        return FileSourceConfig(
+            filename=filename, readonly=readonly, label=label
+        )
 
     async def test_open(self):
         m_open = mock_open()