fix(postprocess): Allow input as file, string, or list

pollination_handlers/inputs/postprocess.py

@@ -1,15 +1,17 @@
 """Handlers for post-processing options."""
+import os
 import json
 from jsonschema import validate
 
 from .helper import get_tempfile
 
 
-def grid_metrics(json_file):
+def grid_metrics(gm_obj):
     """Validate the file for custom grid metrics.
 
         Args:
-            json_file: A JSON file with custom grid metrics.
+            gm_obj: An object with custom grid metrics. This can be either a
+                JSON file, a string, or a list of grid metrics.
 
         Returns:
             str -- Path to a the custom grid metrics file.
@@ -42,8 +44,20 @@ def grid_metrics(json_file):
         }
     }
 
-    with open(json_file) as file:
-        grid_metrics = json.load(file)
+    if isinstance(gm_obj, str):
+        if os.path.isfile(gm_obj):
+            with open(gm_obj) as file:
+                grid_metrics = json.load(file)
+        else:
+            grid_metrics = json.loads(gm_obj)
+    elif isinstance(gm_obj, list):
+        grid_metrics = [_gm for _gm in gm_obj]
+    else:
+        raise TypeError(
+            'Unexpected type of input gm_obj. Valid types are str and list. '
+            'Type of input is: %s.' % type(gm_obj)
+            )
+
     validate(grid_metrics, schema)
 
     file_path = get_tempfile('json', 'grid_metrics')