re-structured meta operations

csst_common/io.py

@@ -69,7 +69,7 @@ REQUIRED_KEYS_IN_META = dict(
 )
 
 
-def generate_meta(**kwargs) -> fits.Header:
+def generate_meta(**kwargs) -> dict:
     """
     Generate metadata.
 
@@ -101,16 +101,10 @@ def generate_meta(**kwargs) -> fits.Header:
     meta["build"] = os.getenv("BUILD", default="__unset__")
     meta["prc_date"] = now()
     meta["data_uuid"] = str(uuid.uuid4())
-    # convert meta to fits header
-    meta_card = fits.Card(
-        keyword="META",
-        value=json.dumps(meta, separators=(",", ":"), ensure_ascii=False),
-    )
-    meta_header = reformat_header(fits.Header(cards=[meta_card]), comment="METADATA")
-    return meta_header
+    return meta
 
 
-def append_meta(hdulist: fits.HDUList, **kwargs) -> fits.HDUList:
+def append_meta(hdulist: fits.HDUList, meta: dict) -> fits.HDUList:
     """
     Append meta to hdulist.
 
@@ -118,8 +112,8 @@ def append_meta(hdulist: fits.HDUList, **kwargs) -> fits.HDUList:
     ----------
     hdulist : fits.HDUList
         HDUList.
-    kwargs : Any
-        Meta data.
+    meta : dict
+        Meta data dict.
 
     Returns
     -------
@@ -127,7 +121,13 @@ def append_meta(hdulist: fits.HDUList, **kwargs) -> fits.HDUList:
         HDUList with meta.
 
     """
-    meta_header = generate_meta(**kwargs)
+    # convert meta to fits header
+    meta_card = fits.Card(
+        keyword="META",
+        value=json.dumps(meta, separators=(",", ":"), ensure_ascii=False),
+    )
+    meta_header = reformat_header(fits.Header(cards=[meta_card]), comment="METADATA")
+    # append meta_header to hdulist[0].header
     hdulist[0].header = append_header(hdulist[0].header, meta_header)
     return hdulist
 

tests/test_io.py

@@ -134,11 +134,12 @@ class TestFitsHeaderOps(unittest.TestCase):
 
     def test_generate_meta(self):
         h = generate_meta()
-        self.assertIsInstance(h, fits.Header)
+        self.assertIsInstance(h, dict)
 
     def test_append_meta(self):
         hdulist = fits.HDUList([fits.PrimaryHDU()])
-        hdulist = append_meta(hdulist, obs_id="123456")
+        meta = generate_meta(obs_id="123456")
+        hdulist = append_meta(hdulist, meta)
         self.assertIn("META", set(hdulist[0].header.keys()))
         meta = extract_meta(hdulist)
         self.assertEqual(meta["obs_id"], "123456")