[Add] version command option

Author: jizhouli

setup.py

@@ -5,7 +5,7 @@
 
 _version_re = re.compile(r'__version__\s+=\s+(.*)')
 
-with open('swagger_py_codegen/__init__.py', 'rb') as f:
+with open('swagger_py_codegen/_version.py', 'rb') as f:
     version = str(ast.literal_eval(_version_re.search(
         f.read().decode('utf-8')).group(1)))
 

swagger_py_codegen/__init__.py

@@ -1,5 +1,4 @@
 from __future__ import absolute_import
 
+from ._version import __version__
 from .command import generate
-
-__version__ = '0.2.2'

swagger_py_codegen/_version.py

@@ -0,0 +1,4 @@
+"""Version information."""
+
+# The following line *must* be the last in the module, exactly as formatted:
+__version__ = "0.2.2"

swagger_py_codegen/command.py

@@ -11,6 +11,7 @@
 import yaml
 import click
 
+from ._version import __version__
 from .flask import FlaskGenerator
 from .parser import Swagger
 from .base import Template
@@ -55,6 +56,13 @@ def _copy_ui_dir(ui_dest, ui_src):
     return status
 
 
+def print_version(ctx, param, value):
+    if not value or ctx.resilient_parsing:
+        return
+    click.echo('current version: %s' % __version__)
+    ctx.exit()
+
+
 @click.command()
 @click.argument('destination', required=True)
 @click.option('-s', '--swagger', '--swagger-doc',
@@ -73,6 +81,9 @@ def _copy_ui_dir(ui_dest, ui_src):
               help='Generate swagger ui.')
 @click.option('-j', '--jobs',
               default=4, help='Parallel jobs for processing.')
+@click.option('--version', is_flag=True, callback=print_version,
+              expose_value=False, is_eager=True,
+              help='Show current version.')
 def generate(destination, swagger_doc, force=False, package=None,
              template_dir=None, specification=False, ui=False, jobs=4):
     pool = Pool(processes=int(jobs))