Implement first two subcommands with argparse

gl-sak

@@ -11,9 +11,9 @@ Usage
 
 E.g., 
 
-  $ ./gl-sak --gitlab=https://code.librehq.com --project foo/bar/myproj baz qux quux
+  $ ./gl-sak --authn-token-file=./seekrit --gitlab=https://code.librehq.com --project foo/bar/myproj get-issue 6
 
-TBD: Document some commands, some of which take further arguments.
+Run with '--help' to see subcommands and their arguments.
 
 GitLab authentication and authorization
 ---------------------------------------
@@ -31,15 +31,18 @@ You could also pass the token directly via the command line with the
 
   $ ./gl-sak --authn-token TOKEN [...]
 
-However, be careful about that: the token could then leak via 'ps'
-listings, shell history, etc.  Only you can decide whether using
-'--authn-token' is a reasonable choice given the security properties
-of your runtime environment, but if you are in any doubt, just use
-'--authn-token-file' instead.
+However, be careful about using the latter way: the token could then
+leak via 'ps' listings, shell history, etc.  Only you can decide
+whether using '--authn-token' is a reasonable choice given the
+security properties of your runtime environment; if you are in any
+doubt, choose '--authn-token-file' instead.
+
 """
 
 import argparse
+import json
 import sys
+
 try:
     import gitlab
 except ImportError:
@@ -68,18 +71,18 @@ for more about the Python GitLab API package.""")
 # Read https://docs.python.org/dev/library/argparse.html#sub-commands
 # when it's time for subcommands.
 
-def list_instance(gl):
+def list_instance(args):
     """Print general information about GitLab server GL.
     This is not really for practical usage; it's more meant to help
     a developer explore what's available via the API."""
-    projects = gl.projects.list(iterator=True)
+    projects = args.gitlab.projects.list(iterator=True)
     for project in projects:
         print(f"*** {project.name_with_namespace} ({project.id}):")
         issues = project.issues.list(get_all=True)
         # for issue in issues:
         #     print(f"{issue}")
         print("")
-    groups = gl.groups.list(iterator=True)
+    groups = args.gitlab.groups.list(iterator=True)
     for group in groups:
         print(f"{group}")
     # This isn't quite right yet:
@@ -88,6 +91,16 @@ def list_instance(gl):
     # for board in boards:
     #     print(f"*** {board} ({board.id}):")
 
+
+def get_issue(args):
+    """TBD: doc string for get_issue()"""
+    issue = args.project.issues.get(vars(args)['issue-id'])
+    print(f"{json.dumps(vars(issue)['_attrs'], indent=2)}")
+    # issues = args.project.issues.list(get_all=True)
+    # for issue in issues:
+    #     print(f"{issue}\n")
+
+
 def main():
     # Set up options and arguments
     arg_parser = argparse.ArgumentParser(
@@ -111,6 +124,20 @@ def main():
         '-F', '--authn-token-file',
         help="File containing the GitLab access token to use for this operation")
 
+    # Set up subcommands.
+    subcommand_parsers = arg_parser.add_subparsers(title="subcommands")
+
+    get_issue_parser = subcommand_parsers.add_parser(
+        'get-issue', help=get_issue.__doc__)
+
+    get_issue_parser.set_defaults(func=get_issue)
+    get_issue_parser.add_argument('issue-id', type=int)
+
+    list_instance_parser = subcommand_parsers.add_parser(
+        'list-instance', help=list_instance.__doc__)
+    list_instance_parser.set_defaults(func=list_instance)
+
+    # Parse command line.
     args = arg_parser.parse_args()
 
     if args.authn_token_file is not None:
@@ -119,27 +146,27 @@ def main():
 
     # Set up the GitLab instance.
     gl = gitlab.Gitlab(url=args.gitlab,
-                        private_token=args.authn_token)
+                       private_token=args.authn_token)
     gl.auth()
 
     ## WARNING: Turning on debugging can cause credentials and other
     ## sensitive data to be printed on the console.
     # gl.enable_debug()
 
-    ## Uncomment for exploration.
-    # list_instance(gl)
-
     # Instantiate specified project, if any.
-    project = None
+    proj = None
     try:
-        project = gl.projects.get(args.project, None)
+        proj = gl.projects.get(args.project, None)
     except gitlab.exceptions.GitlabGetError as e:
         sys.stderr.write(f"ERROR: No such project '{args.project}'\n")
         sys.exit(1)
 
-    issues = project.issues.list(get_all=True)
-    for issue in issues:
-        print(f"{issue}\n")
+    # Replace identifiers with now-instantiated objects.
+    args.gitlab = gl
+    args.project = proj
+
+    # Call the subcommand.
+    args.func(args)
 
 
 if __name__ == '__main__':

run.sh.tmpl

@@ -2,4 +2,5 @@
 
 ./gl-sak --authn-token-file="XXX" \
          --gitlab="https://code.librehq.com" \
-         --project="ots/clients/YYY/ZZZ"
+         --project="ots/clients/YYY/ZZZ" \
+         get-issue 6