added load_config and try_load_config functions

changelog.md

@@ -3,7 +3,8 @@
 ## [1.1.0] - work in progress
 
 ### Added 
-   
+    - utils.try_load_config
+    - utils.load_config
     - Endpoint module move in (from pmworker)
 
 ## [1.0.0] - 25 Apr 2020

mglib/utils.py

@@ -1,5 +1,8 @@
 import os
 import logging
+import importlib.machinery
+import importlib.util
+
 
 logger = logging.getLogger(__name__)
 
@@ -84,3 +87,46 @@ def get_assigns_after_delete(total_pages, deleted_pages):
     page_numbers = range(1, len(pages) + 1)
 
     return list(zip(page_numbers, pages))
+
+
+def load_config(config_file):
+
+    loader_ = importlib.machinery.SourceFileLoader(
+        "config",
+        config_file
+    )
+    spec = importlib.util.spec_from_file_location(
+        "config", config_file, loader=loader_
+    )
+    mod = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(mod)
+    # and stop looking for ther configs.
+    cfg_papermerge = vars(mod)
+    cfg_file_found = True
+
+    return cfg_papermerge, cfg_file_found
+
+
+def try_load_config(config_locations, config_env_var_name):
+
+    cfg_file_found = False
+    cfg_papermerge = {}
+
+    for config_file in config_locations:
+        if os.path.exists(config_file):
+            cfg_papermerge, cfg_file_found = load_config(config_file)
+            if cfg_file_found:
+                break
+
+    if not cfg_file_found:
+        config_file = os.environ.get(config_env_var_name, False)
+        if config_file:
+            try:
+                cfg_papermerge, cfg_file_found = load_config(config_file)
+            except FileNotFoundError:
+                err_msg = f"Failed attempted to read" +\
+                    f" configuration file '{config_file}'" +\
+                    f" pointed by environment variable '{config_env_var_name}'"
+                raise FileNotFoundError(err_msg)
+
+    return cfg_papermerge

setup.py

@@ -6,7 +6,7 @@ with open("README.md", "r") as fh:
 
 setup(
     name="mglib",
-    version="1.1.0",
+    version="1.1.1",
     author="Eugen Ciur",
     author_email="eugen@papermerge.com",
     url="https://github.com/papermerge/mglib",