The nova.api.openstack.compute.limits Module

Module dedicated functions/classes dealing with rate limiting requests.

class Limit(verb, uri, regex, value, unit)

Bases: object

Stores information about a limit for HTTP requests.

UNITS = {3600: 'HOUR', 1: 'SECOND', 86400: 'DAY', 60: 'MINUTE'}

UNIT_MAP = {'SECOND': 1, 'MINUTE': 60, 'DAY': 86400, 'HOUR': 3600}

display()

Return a useful representation of this class.

display_unit()

Display the string name of the unit.

k = 60

v = 'MINUTE'

class Limiter(limits, **kwargs)

Bases: object

Rate-limit checking class which handles limits in memory.

check_for_delay(verb, url, username=None)

Check the given verb/user/user triplet for limit.

@return: Tuple of delay (in seconds) and error message (or None, None)

get_limits(username=None)

Return the limits for a given user.

static parse_limits(limits)

Convert a string into a list of Limit instances. This implementation expects a semicolon-separated sequence of parenthesized groups, where each group contains a comma-separated sequence consisting of HTTP method, user-readable URI, a URI reg-exp, an integer number of requests which can be made, and a unit of measure. Valid values for the latter are “SECOND”, “MINUTE”, “HOUR”, and “DAY”.

@return: List of Limit instances.

class LimitsController

Bases: object

Controller for accessing limits in the OpenStack API.

create(req, body)

Create a new limit.

delete(req, id)

Delete the limit.

detail(req)

Return limit details.

index(req)

Return all global and rate limit information.

show(req, id)

Show limit information.

update(req, id, body)

Update existing limit.

class LimitsTemplate

Bases: nova.api.openstack.xmlutil.TemplateBuilder

construct()

class RateLimitingMiddleware(application, limits=None, limiter=None, **kwargs)

Bases: nova.wsgi.Middleware

Rate-limits requests passing through this middleware. All limit information is stored in memory for this implementation.

class WsgiLimiter(limits=None)

Bases: object

Rate-limit checking from a WSGI application. Uses an in-memory Limiter.

To use, POST /<username> with JSON data such as:

{
    "verb" : GET,
    "path" : "/servers"
}

and receive a 204 No Content, or a 403 Forbidden with an X-Wait-Seconds header containing the number of seconds to wait before the action would succeed.

class WsgiLimiterProxy(limiter_address)

Bases: object

Rate-limit requests based on answers from a remote source.

check_for_delay(verb, path, username=None)

static parse_limits(limits)

Ignore a limits string–simply doesn’t apply for the limit proxy.

@return: Empty list.

create_resource()