The nova.wsgi Module

Utility methods for working with WSGI servers.

class Application

Bases: object

Base WSGI application wrapper. Subclasses need to implement __call__.

classmethod factory(global_config, **local_config)

Used for paste app factories in paste.deploy config files.

Any local configuration (that is, values under the [app:APPNAME] section of the paste config) will be passed into the __init__ method as kwargs.

A hypothetical configuration would look like:

[app:wadl] latest_version = 1.3 paste.app_factory = nova.api.fancy_api:Wadl.factory

which would result in a call to the Wadl class as

import nova.api.fancy_api fancy_api.Wadl(latest_version=‘1.3’)

You could of course re-implement the factory method in subclasses, but using the kwarg passing it shouldn’t be necessary.

class Debug(application)

Bases: nova.wsgi.Middleware

Helper class for debugging a WSGI application.

Can be inserted into any WSGI application chain to get information about the request and response.

static print_generator(app_iter)

Iterator that prints the contents of a wrapper string.

class Loader(config_path=None)

Bases: object

Used to load WSGI applications from paste configurations.

load_app(name)

Return the paste URLMap wrapped WSGI application.

Parameters:name – Name of the application to load. Returns:Paste URLMap object wrapping the requested application. Raises:nova.exception.PasteAppNotFound

class Middleware(application)

Bases: nova.wsgi.Application

Base WSGI middleware.

These classes require an application to be initialized that will be called next. By default the middleware will simply call its wrapped app, or you can override __call__ to customize its behavior.

classmethod factory(global_config, **local_config)

Used for paste app factories in paste.deploy config files.

Any local configuration (that is, values under the [filter:APPNAME] section of the paste config) will be passed into the __init__ method as kwargs.

A hypothetical configuration would look like:

[filter:analytics] redis_host = 127.0.0.1 paste.filter_factory = nova.api.analytics:Analytics.factory

which would result in a call to the Analytics class as

import nova.api.analytics analytics.Analytics(app_from_paste, redis_host=‘127.0.0.1’)

You could of course re-implement the factory method in subclasses, but using the kwarg passing it shouldn’t be necessary.

process_request(req)

Called on each request.

If this returns None, the next application down the stack will be executed. If it returns a response then that response will be returned and execution will stop here.

process_response(response)

Do whatever you’d like to the response.

class Request(environ, *args, **kwargs)

Bases: webob.request.Request

class Router(mapper)

Bases: object

WSGI middleware that maps incoming requests to WSGI apps.

class Server(name, app, host='0.0.0.0', port=0, pool_size=None, protocol=<class eventlet.wsgi.HttpProtocol at 0x7f32efb52e20>, backlog=128, use_ssl=False, max_url_len=None)

Bases: oslo_service.service.ServiceBase

Server class to manage a WSGI server, serving a WSGI application.

default_pool_size = 1000

reset()

Reset server greenpool size to default.

Returns:None

start()

Start serving a WSGI application.

Returns:None

stop()

Stop this server.

This is not a very nice action, as currently the method by which a server is stopped is by killing its eventlet.

Returns:None

wait()

Block, until the server has stopped.

Waits on the server’s eventlet to finish, then returns.

Returns:None