Merge pull request #2 from berndverst/master

Minimal Flask app

Author: Cory Fowler

README.md

@@ -1,3 +1,11 @@
+# Python Flask app on Azure App Service Web
+
+This is a minimal sample app that demonstrates how to run a Python Flask application on Azure App Service Web.
+
+This repository can directly be deployed to Azure App Service.
+
+For more information, please see the [Python on App Service Quickstart docs](https://docs.microsoft.com/en-us/azure/app-service-web/app-service-web-get-started-python).
+
 # Contributing
 
 This project has adopted the [Microsoft Open Source Code of Conduct](https://opensource.microsoft.com/codeofconduct/). For more information see the [Code of Conduct FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or contact [opencode@microsoft.com](mailto:opencode@microsoft.com) with any additional questions or comments.

main.py

@@ -0,0 +1,9 @@
+from flask import Flask
+app = Flask(__name__)
+
+@app.route('/')
+def hello_world():
+  return 'Hello, World!'
+
+if __name__ == '__main__':
+  app.run()

requirements.txt

@@ -0,0 +1 @@
+Flask==0.12.1

virtualenv_proxy.py

@@ -0,0 +1,95 @@
+import datetime
+import os
+import sys
+import traceback
+
+if sys.version_info[0] == 3:
+    def to_str(value):
+        return value.decode(sys.getfilesystemencoding())
+
+    def execfile(path, global_dict):
+        """Execute a file"""
+        with open(path, 'r') as f:
+            code = f.read()
+        code = code.replace('\r\n', '\n') + '\n'
+        exec(code, global_dict)
+else:
+    def to_str(value):
+        return value.encode(sys.getfilesystemencoding())
+
+def log(txt):
+    """Logs fatal errors to a log file if WSGI_LOG env var is defined"""
+    log_file = os.environ.get('WSGI_LOG')
+    if log_file:
+        f = open(log_file, 'a+')
+        try:
+            f.write('%s: %s' % (datetime.datetime.now(), txt))
+        finally:
+            f.close()
+
+def get_wsgi_handler(handler_name):
+    if not handler_name:
+        raise Exception('WSGI_ALT_VIRTUALENV_HANDLER env var must be set')
+
+    if not isinstance(handler_name, str):
+        handler_name = to_str(handler_name)
+
+    module_name, _, callable_name = handler_name.rpartition('.')
+    should_call = callable_name.endswith('()')
+    callable_name = callable_name[:-2] if should_call else callable_name
+    name_list = [(callable_name, should_call)]
+    handler = None
+    last_tb = ''
+
+    while module_name:
+        try:
+            handler = __import__(module_name, fromlist=[name_list[0][0]])
+            last_tb = ''
+            for name, should_call in name_list:
+                handler = getattr(handler, name)
+                if should_call:
+                    handler = handler()
+            break
+        except ImportError:
+            module_name, _, callable_name = module_name.rpartition('.')
+            should_call = callable_name.endswith('()')
+            callable_name = callable_name[:-2] if should_call else callable_name
+            name_list.insert(0, (callable_name, should_call))
+            handler = None
+            last_tb = ': ' + traceback.format_exc()
+
+    if handler is None:
+        raise ValueError('"%s" could not be imported%s' % (handler_name, last_tb))
+
+    return handler
+
+activate_this = os.getenv('WSGI_ALT_VIRTUALENV_ACTIVATE_THIS')
+if not activate_this:
+    raise Exception('WSGI_ALT_VIRTUALENV_ACTIVATE_THIS is not set')
+
+def get_virtualenv_handler():
+    log('Activating virtualenv with %s\n' % activate_this)
+    execfile(activate_this, dict(__file__=activate_this))
+
+    log('Getting handler %s\n' % os.getenv('WSGI_ALT_VIRTUALENV_HANDLER'))
+    handler = get_wsgi_handler(os.getenv('WSGI_ALT_VIRTUALENV_HANDLER'))
+    log('Got handler: %r\n' % handler)
+    return handler
+
+def get_venv_handler():
+    log('Activating venv with executable at %s\n' % activate_this)
+    import site
+    sys.executable = activate_this
+    old_sys_path, sys.path = sys.path, []
+
+    site.main()
+
+    sys.path.insert(0, '')
+    for item in old_sys_path:
+        if item not in sys.path:
+            sys.path.append(item)
+
+    log('Getting handler %s\n' % os.getenv('WSGI_ALT_VIRTUALENV_HANDLER'))
+    handler = get_wsgi_handler(os.getenv('WSGI_ALT_VIRTUALENV_HANDLER'))
+    log('Got handler: %r\n' % handler)
+    return handler

web.2.7.config

@@ -0,0 +1,9 @@
+<configuration>
+  <appSettings>
+    <add key="WSGI_ALT_VIRTUALENV_HANDLER" value="main.app" />
+    <add key="WSGI_ALT_VIRTUALENV_ACTIVATE_THIS"
+         value="D:\home\site\wwwroot\env\Scripts\activate_this.py" />
+    <add key="pythonpath" value="%SystemDrive%\home\site\wwwroot" />
+    <add key="WSGI_HANDLER" value="virtualenv_proxy.get_virtualenv_handler()" />
+  </appSettings>
+</configuration>

web.3.4.config

@@ -0,0 +1,9 @@
+<configuration>
+  <appSettings>
+    <add key="WSGI_ALT_VIRTUALENV_HANDLER" value="main.app" />
+    <add key="WSGI_ALT_VIRTUALENV_ACTIVATE_THIS"
+         value="D:\home\site\wwwroot\env\Scripts\python.exe" />
+    <add key="pythonpath" value="%SystemDrive%\home\site\wwwroot" />
+    <add key="WSGI_HANDLER" value="virtualenv_proxy.get_venv_handler()" />
+  </appSettings>
+</configuration>