CLI shows help without args (broadinstitute#100)

* Lint.

* Add vscode configs to the ignore file.

* Update build badges.

* Show help when no arguments provided.

* Make it work.

Author: rexwangcc

.gitignore

@@ -5,6 +5,9 @@ __pycache__/
 docker/cromwell-metadata/cromwell_credentials.txt
 docker/cromwell-metadata/caas_key.json
 
+# IDE
+.vscode/
+
 # Sphinx documentation
 docs/_build/
 

README.rst

@@ -5,8 +5,8 @@ Cromwell-tools
     :target: https://quay.io/repository/broadinstitute/cromwell-tools
     :alt: Container Build Status
 
-.. image:: https://github.com/broadinstitute/cromwell-tools/workflows/Tests%20on%20Pull%20Requests%20and%20Master/badge.svg?branch=master
-    :target: https://github.com/broadinstitute/cromwell-tools/actions?query=workflow%3A%22Tests+on+Pull+Requests+and+Master%22+branch%3Arex-switch-to-GithubActions
+.. image:: https://github.com/broadinstitute/cromwell-tools/workflows/Tests%20on%20Pull%20Requests%20and%20Master/badge.svg
+    :target: https://github.com/broadinstitute/cromwell-tools/actions?query=workflow%3A%22Tests+on+Pull+Requests+and+Master%22+branch%3Amaster
     :alt: Unit Test Status
 
 .. image:: https://img.shields.io/readthedocs/cromwell-tools/latest.svg?label=ReadtheDocs%3A%20Latest&logo=Read%20the%20Docs&style=flat-square

cromwell_tools/cli.py

@@ -4,15 +4,23 @@
 from cromwell_tools.cromwell_auth import CromwellAuth
 from cromwell_tools.diag import task_runtime
 from cromwell_tools import __version__
+import sys
 
 
 diagnostic_index = {'task_runtime': task_runtime.run}
 
 
+class DefaultHelpParser(argparse.ArgumentParser):
+    def error(self, message):
+        sys.stderr.write('error: %s\n' % message)
+        self.print_help()
+        sys.exit(2)
+
+
 def parser(arguments=None):
     # TODO: dynamically walk through the commands and automatcally create parsers here
 
-    main_parser = argparse.ArgumentParser()
+    main_parser = DefaultHelpParser()
 
     # Check the installed version of Cromwell-tools
     main_parser.add_argument(
@@ -249,6 +257,10 @@ def add_auth_args(subcommand_parser):
     # group all of the arguments
     args = vars(main_parser.parse_args(arguments))
 
+    # Return help messages if no arguments provided
+    if not args['command']:
+        main_parser.error("No commands/arguments provided!")
+
     # TODO: see if this can be moved or if the commands can be populated from above
     if args['command'] in (
         'submit',

cromwell_tools/cromwell_api.py

@@ -613,5 +613,5 @@ def _check_and_raise_status(response: requests.Response) -> None:
         if not response.ok:
             raise requests.exceptions.HTTPError(
                 'Error Code {0}: {1}'.format(response.status_code, response.text),
-                response=response
+                response=response,
             )