More fixes for dotenv compatibility

- Handle env files with empty and malformed lines. Just skip those and
  ignore them.

supervisor/options.py

@@ -1992,30 +1992,38 @@ def load_external_environment_definition_for_config(cls, config):
 
  for line in envdata.splitlines():
  line = line.strip()
- if line.startswith('#'): # ignore comments
+ if not line or line.startswith('#'): # ignore comments and empty lines
  continue
 
- key, val = [s.strip() for s in line.split("=", 1)]
- if key:
- # for compatibility with .env files and the npm dotenv library, if the value is quoted let's
- # unquote it. Also, double quoted strings get embedded '\\n' chars expanded to real newlines.
-  # Don't strip whitespace inside quoted values.
-  if val.startswith("\""):
-  val = val.strip("\"")
+ line_parts = line.split("=", 1) # ignore malformed lines
+ if len(line_parts) != 2:
+ continue
+
+ key, val = [s.strip() for s in line_parts]
+ if not key or not val:
+ continue
 
- # expand embedded '\n' chars into actual newlines
- val.replace("\\n", "\n")
+ # for compatibility with .env files and the npm dotenv library, if the value is quoted let's
+ # unquote it. Also, double quoted strings get embedded '\\n' chars expanded to real newlines.
+ # Don't strip whitespace inside quoted values.
+ if val.startswith("\""):
+ val = val.strip("\"")
 
- elif val.startswith("'"):
- val = val.strip("'")
- elif val.startswith("`"):
- val = val.strip("`")
+ # expand embedded '\n' chars into actual newlines
+ val.replace("\\n", "\n")
 
- extra_env[key.upper()] = val
+ elif val.startswith("'"):
+ val = val.strip("'")
+ elif val.startswith("`"):
+ val = val.strip("`")
+
+ extra_env[key.upper()] = val
 
  if extra_env:
+ print(f"updating process env with: {extra_env}")
  env.update(extra_env)
 
+
  return env
 
 class EventListenerConfig(ProcessConfig):