Switch from argparse to click

This patch switches from argparse to click for handling command line
arguments in preparation to introducing multiple command line argument
groups.

This patch does not change the functionality. The CLI still only handles
DNS modifications. But this is now in its own group and we can easily
add another one, for example, to handle IP address registration.

README.md

@@ -36,25 +36,32 @@ This can be useful if, for example, all your domains also have an alternate doma
 
 ```
 ❯ proteuscmd
-usage: proteuscmd [-h] [--view {all,intern,extern}] {get,set,delete} domain [target]
+Usage: python -m proteuscmd [OPTIONS] COMMAND [ARGS]...
+
+Options:
+  --help  Show this message and exit.
+
+Commands:
+  dns  Get information about or update DNS entries.
+  ip   Register IP addresses.
 ```
 
 Get information about a DNS record:
 ```
-❯ proteuscmd get lktest.uni-osnabrueck.de
+❯ proteuscmd dns get lktest.uni-osnabrueck.de
 ```
 
 Set an alias record:
 ```
-❯ proteuscmd set lktest.uni-osnabrueck.de vm123.rz.uni-osnabrueck.de
+❯ proteuscmd dns set lktest.uni-osnabrueck.de vm123.rz.uni-osnabrueck.de
 ```
 
 Set a host record:
 ```
-❯ proteuscmd set lktest.uni-osnabrueck.de 131.12.65.123
+❯ proteuscmd dns set lktest.uni-osnabrueck.de 131.12.65.123
 ```
 
 Delete a record:
 ```
-❯ proteuscmd delete lktest.uni-osnabrueck.de
+❯ proteuscmd dns delete lktest.uni-osnabrueck.de
 ```

proteuscmd/__main__.py

@@ -1,43 +1,83 @@
-import argparse
+import click
+import json
 
+from functools import wraps
 from proteuscmd.config import proteus_from_config
 
-__config = None
+__views = click.Choice(('intern', 'extern', 'all'), case_sensitive=False)
 
 
-def main():
-    parser = argparse.ArgumentParser(description='Proteus DNS command line')
-    parser.add_argument('--view',
-                        choices=('all', 'intern', 'extern'),
-                        default='all',
-                        help='View to operate on')
-    parser.add_argument('operation',
-                        choices=('get', 'set', 'delete'),
-                        help='Operation to perform on domain')
-    parser.add_argument('domain',
-                        help='Domain to operate on')
-    parser.add_argument('target',
-                        nargs='?',
-                        help='Target of the DNS record')
+def with_proteus(f):
+    '''Provide a Proteus client as first parameter of the wraped function.
+    Print the result if one exists.
+    '''
+    @wraps(f)
+    def decorated(*args, **kwargs):
+        with proteus_from_config() as proteus:
+            data = f(proteus, *args, **kwargs)
+        if data:
+            print(json.dumps(data, indent=2))
+    return decorated
 
-    args = parser.parse_args()
 
-    if args.operation == 'set' and not args.target:
-        parser.error("set requires a target.")
+@click.group()
+def cli():
+    pass
 
-    # Interaction with Proteus
-    with proteus_from_config() as proteus:
-        views = proteus.get_requested_views(args.view)
 
-        for name, view in views:
-            print(name)
-            if args.operation == 'get':
-                print('\n'.join(proteus.get_record(view, args.domain)))
-            elif args.operation == 'set':
-                print(proteus.set_record(view, args.domain, args.target))
-            elif args.operation == 'delete':
-                print(proteus.delete_record(view, args.domain))
+@cli.group()
+def dns():
+    '''Get information about or update DNS entries.
+    '''
+    pass
+
+
+@cli.group()
+def ip():
+    '''Register IP addresses.
+    Not implemented yet.
+    '''
+    pass
+
+
+@dns.command()
+@click.option('--view', default='all', type=__views)
+@click.argument('domain')
+@with_proteus
+def get(proteus, view, domain):
+    '''Get information about a DNS entry.
+    '''
+    views = proteus.get_requested_views(view)
+    return {name: proteus.get_record(view, domain) for name, view in views}
+
+
+@dns.command()
+@click.option('--view', default='all', type=__views)
+@click.argument('domain')
+@click.argument('target')
+@with_proteus
+def set(proteus, view, domain, target):
+    '''Set DNS entry in Proteus
+    '''
+    views = proteus.get_requested_views(view)
+    result = {}
+    for name, view in views:
+        proteus.set_record(view, domain, target)
+        result[name] = proteus.get_record(view, domain)
+    return result
+
+
+@dns.command()
+@click.option('--view', default='all', type=__views)
+@click.argument('domain')
+@with_proteus
+def delete(proteus, view, domain):
+    '''Delete DNS record in Proteus
+    '''
+    views = proteus.get_requested_views(view)
+    for name, view in views:
+        proteus.delete_record(view, domain)
 
 
 if __name__ == '__main__':
-    main()
+    cli()

proteuscmd/api.py

@@ -171,8 +171,9 @@ def get_record(self, view, domain):
             + self.get_entities_by_name(host, parent, 'AliasRecord')
         for record in data:
             properties = record['properties'].split('|')
-            return [prop for prop in filter(bool, properties)]
-        return []
+            properties = [prop.split('=', 1) for prop in properties if prop]
+            return {prop[0]: prop[1] for prop in properties}
+        return {}
 
     def set_record(self, view, domain, target):
 

requirements.txt

@@ -1 +1,2 @@
 requests
+Click