feat: add argparse

config.toml

@@ -122,8 +122,8 @@ scripts = [
 reload = ['echo', 'this is my reload command']
 
 #########################
-settings for some
+# settings for some
-commonly used apps
+# commonly used apps
 #########################
 
 [task.niri]

userctx.py

@@ -1,9 +1,10 @@
 #!/usr/bin/env python3
-import os, sys, subprocess, tomllib
+import os, sys, subprocess, tomllib, argparse
 
 COMMAND_LIST = 'list'
 COMMAND_LOAD = 'load'
 COMMAND_SAVE = 'save'
+COMMAND_CTX_NAME = 'context_name'
 COMMANDS_ALL = [COMMAND_LIST, COMMAND_LOAD, COMMAND_SAVE]
 
 SECTION_GENERAL = 'general'
@@ -27,15 +28,8 @@ ENV_CONTEXT_NAME = 'CONTEXT_NAME'
 ENV_CONTEXT_SRC = 'CONTEXT_SRC'
 ENV_CONTEXT_DST = 'CONTEXT_DST'
 
-HELP_MESSAGE = f'''Usage: {os.path.basename(sys.argv[0])} <command> [context_name]
+APP_NAME = os.path.basename(sys.argv[0])
-
+APP_DESC = 'A simple configuration switcher for various usage scenarios.'
-Commands are: 
-    {COMMAND_LIST} - to list installed contexts (from $HOME/.config/userctx)
-    {COMMAND_LOAD} - to load context "context_name" 
-    {COMMAND_SAVE} - to save current configs of managed apps as context
-
-"context_name" - must be a directory name present in $HOME/.config/userctx'''
-
 HOME = os.path.expanduser('~')
 XDG_CONFIG_HOME = os.getenv('XDG_CONFIG_HOME', os.path.join(HOME, '.config'))
 
@@ -223,8 +217,8 @@ class ContextManager(object):
     def __init__(self, config: ContextManagerConfig):
         self.config = config
 
-    def get_contexts_list(self) -> str:
+    def print_contexts_list(self) -> str:
-        return '\n'.join(self.config.get_contexts_list())
+        print('\n'.join(self.config.get_contexts_list()))
 
     def apply_context(self, context_name: str) -> None:
         print(f'loading and applying context: "{context_name}"')
@@ -252,37 +246,37 @@ class ContextManager(object):
 
 
 class Runner(object):
-    def __init__(self):
-        self.cmd = sys.argv[1] if len(sys.argv) > 1 else ''
-        self.context_name = ' '.join(sys.argv[2:]) if len(sys.argv) > 2 else ''
-        self.config_file_path = os.path.join(XDG_CONFIG_HOME, 'userctx', 'config.toml')
-
     def run(self) -> int:
-        if self.cmd == '':
+        p = argparse.ArgumentParser(prog=APP_NAME, description=APP_DESC)
-            print(HELP_MESSAGE)
+        p.add_argument('-c', '--config', help='path to config file, default: %(default)s',
-            return 0
+                       default=os.path.join(XDG_CONFIG_HOME, 'userctx', 'config.toml'))
-        if self.cmd not in COMMANDS_ALL:
+        subp = p.add_subparsers(help='command to execute', dest='command')
-            print(f'invalid command. valid commands are: {", ".join(COMMANDS_ALL)}')
+        loadp = subp.add_parser(COMMAND_LOAD, help='load context (provide name of context)')
+        loadp.add_argument(COMMAND_CTX_NAME, help='name of context to load')
+        listp = subp.add_parser(COMMAND_LIST, help='list available contexts')
+        savep = subp.add_parser(COMMAND_SAVE, help='save current context (provide name of context)')
+        savep.add_argument(COMMAND_CTX_NAME, help='name of context to save')
+        try: # just in case
+            args = p.parse_args()
+        except Exception as e:
+            print("error parsing command-line arguments:", e)
             return 1
-        if self.cmd in [COMMAND_LOAD, COMMAND_SAVE]  and self.context_name == '':
-            print('invalid command. please provide name of context to apply')
-            return 2
         try:
-            config = ContextManagerConfig(self.config_file_path)
+            config = ContextManagerConfig(args.config)
         except Exception as e:
             print("error loading config:", e)
-            return 3
+            return 2
         try:
             ctxmgr = ContextManager(config)
-            if self.cmd == COMMAND_LIST:
+            if args.command == COMMAND_LIST:
-                print(ctxmgr.get_contexts_list())
+                ctxmgr.print_contexts_list()
-            elif self.cmd == COMMAND_LOAD:
+            elif args.command == COMMAND_LOAD:
-                ctxmgr.apply_context(self.context_name)
+                ctxmgr.apply_context(args.__dict__[COMMAND_CTX_NAME]) # guaranteed to be present by argparse
-            elif self.cmd == COMMAND_SAVE:
+            elif args.command == COMMAND_SAVE:
-                print('save not implemented')
+                raise Exception('"save" not implemented')
         except Exception as e:
-            print(f'error executing command "{self.cmd}":', e)
+            print(f'error executing command:', e)
-            return 4
+            return 3
         return 0