Source code for zope.publisher.interfaces.http

# Copyright (c) 2001, 2002 Zope Foundation and Contributors.
# All Rights Reserved.
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
"""HTTP-related publisher interfaces.

__docformat__ = "reStructuredText"

from zope.interface import Interface
from zope.interface import Attribute
from zope.interface import implementer
from zope.interface.common.interfaces import IException

from zope.publisher.interfaces import IApplicationRequest
from zope.publisher.interfaces import IPublishTraverse
from zope.publisher.interfaces import IRequest
from zope.publisher.interfaces import IResponse
from zope.publisher.interfaces import IView

from .._compat import _u

[docs]class IVirtualHostRequest(Interface): """The support for virtual hosts in Zope is very important. In order to make virtual hosts working, we need to support several methods in our Request object. This interface defines the required methods. """ def setVirtualHostRoot(names): """Marks the currently traversed object as the root of a virtual host. Any path elements traversed up to that Set the names which compose the application path. These are the path elements that appear in the beginning of the generated URLs. Should be called during traversal. """ def getVirtualHostRoot(): """Returns the object which is the virtual host root for this request Return None if setVirtualHostRoot hasn't been called. """ def setApplicationServer(host, proto='http', port=None): """Override the host, protocol and port parts of generated URLs. This affects automatically inserted <base> tags and URL getters in the request, but not things like @@absolute_url views. """ def shiftNameToApplication(): """Add the name being traversed to the application name This is only allowed in the case where the name is the first name. A Value error is raised if the shift can't be performed. """
[docs]class IHTTPApplicationRequest(IApplicationRequest, IVirtualHostRequest): """HTTP request data. This object provides access to request data. This includes, the input headers, server data, and cookies. Request objects are created by the object publisher and will be passed to published objects through the argument name, REQUEST. The request object is a mapping object that represents a collection of variable to value mappings. In addition, variables are divided into four categories: - Environment variables These variables include input headers, server data, and other request-related data. The variable names are as <a href="">specified</a> in the <a href="">CGI specification</a> - Cookies These are the cookie data, if present. - Other Data that may be set by an application object. The request object may be used as a mapping object, in which case values will be looked up in the order: environment variables, other variables, cookies, and special. """ def __getitem__(key): """Return HTTP request data Request data sre retrieved from one of: - Environment variables These variables include input headers, server data, and other request-related data. The variable names are as <a href="">specified</a> in the <a href="">CGI specification</a> - Cookies These are the cookie data, if present. Cookies are searched before environmental data. """ def getCookies(): """Return the cookie data Data are returned as a mapping object, mapping cookie name to value. """ return IMapping(str, str) cookies = Attribute( """Request cookie data This is a read-only mapping from variable name to value. """) def getHeader(name, default=None, literal=False): """Get a header value Return the named HTTP header, or an optional default argument or None if the header is not found. Note that both original and CGI-ified header names are recognized, e.g. 'Content-Type', 'CONTENT_TYPE' and 'HTTP_CONTENT_TYPE' should all return the Content-Type header, if available. If the literal argument is passed, the header is searched 'as is', eg: only if the case matches. """ headers = Attribute( """Request header data This is a read-only mapping from variable name to value. It does *not* support iteration. """) URL = Attribute( """Request URL data When converted to a string, this gives the effective published URL. This object can also be used as a mapping object. The key must be an integer or a string that can be converted to an integer. A non-negative integer returns a URL n steps from the URL of the top-level application objects. A negative integer gives a URL that is -n steps back from the effective URL. For example, 'request.URL[-2]' is equivalent to the Zope 2 'request["URL2"]'. The notion is that this would be used in path expressions, like 'request/URL/-2'. """) def getURL(level=0, path_only=False): """Return the published URL with level names removed from the end. If path_only is true, then only a path will be returned. """ def getApplicationURL(depth=0, path_only=False): """Return the application URL plus depth steps If path_only is true, then only a path will be returned. """
[docs]class IHTTPPublisher(IPublishTraverse): """HTTP Publisher"""
class IHTTPRequest(IRequest): method = Attribute("Request method, normalized to upper case") def setPathSuffix(steps): """Add additional traversal steps to be taken after all other traversal This is used to handle HTTP request methods (except for GET and POST in the case of browser requests) and XML-RPC methods. """ locale = Attribute( "Return the locale object associated with this request.") def setupLocale(): """Setup the locale object based on languages returned by IUserPreferredLanguages adapter. """
[docs]class IHTTPView(IView): "HTTP View"
class IHTTPCredentials(Interface): # TODO: Eventially this will be a different method def _authUserPW(): """Return (login, password) if there are basic credentials; return None if there aren't.""" def unauthorized(challenge): """Issue a 401 Unauthorized error (asking for login/password). The challenge is the value of the WWW-Authenticate header."""
[docs]class IHTTPApplicationResponse(Interface): """HTTP Response""" def redirect(location, status=302, trusted=False): """Causes a redirection without raising an error. By default redirects are untrusted which restricts target URLs to the same host that the request was sent to. If the `trusted` flag is set, redirects are allowed for any target URL. """
[docs]class IHeaderOutput(Interface): """Interface for setting HTTP response headers. This allows the HTTP server and the application to both set response headers. zope.publisher.http.HTTPResponse is optionally passed an object which implements this interface in order to intermingle its headers with the HTTP server's response headers, and for the purpose of better logging. """ def setResponseStatus(status, reason): """Sets the status code and the accompanying message. """ def setResponseHeaders(mapping): """Sets headers. The headers must be Correctly-Cased. """ def appendResponseHeaders(lst): """Sets headers that can potentially repeat. Takes a list of strings. """ def wroteResponseHeader(): """Returns a flag indicating whether the response header has already been sent. """ def setAuthUserName(name): """Sets the name of the authenticated user so the name can be logged. """
[docs]class IResult(Interface): """An iterable that provides the body data of the response. For simplicity, an adapter to this interface may in fact return any iterable, without needing to strictly have the iterable provide IResult. IMPORTANT: The result object may be held indefinitely by a server and may be accessed by arbitrary threads. For that reason the result should not hold on to any application resources (i.e., should not have a connection to the database) and should be prepared to be invoked from any thread. This iterable should generally be appropriate for WSGI iteration. Each element of the iteration should generally be much larger than a character or line; concrete advice on chunk size is hard to come by, but a single chunk of even 100 or 200 K is probably fine. If the IResult is a string, then, the default iteration of per-character is wildly too small. Because this is such a common case, if a string is used as an IResult then this is special-cased to simply convert to a tuple of one value, the string. Adaptation to this interface provides the opportunity for efficient file delivery, pipelining hooks, and more. """ def __iter__(): """iterate over the values that should be returned as the result. See IHTTPResponse.setResult. """
[docs]class IHTTPResponse(IResponse): """An object representation of an HTTP response. The Response type encapsulates all possible responses to HTTP requests. Responses are normally created by the object publisher. A published object may recieve the response object as an argument named 'RESPONSE'. A published object may also create its own response object. Normally, published objects use response objects to: - Provide specific control over output headers, - Set cookies, or - Provide stream-oriented output. If stream oriented output is used, then the response object passed into the object must be used. """ authUser = Attribute('The authenticated user message.') def getStatus(): """Returns the current HTTP status code as an integer. """ def setStatus(status, reason=None): """Sets the HTTP status code of the response The status parameter must be either an integer (preferred), a value that can be converted to an integer using the int() function, or one of the standard status messages listed in the status_codes dict of the zope.publisher.http module (including "OK", "NotFound", and so on). If the parameter is some other value, the status will be set to 500. The reason parameter is a short message to be sent with the status code to the client. If reason is not provided, a standard reason will be supplied, falling back to "Unknown" for unregistered status codes. """ def getStatusString(): """Return the status followed by the reason.""" def setHeader(name, value, literal=False): """Sets an HTTP return header "name" with value "value" The previous value is cleared. If the literal flag is true, the case of the header name is preserved, otherwise word-capitalization will be performed on the header name on output. """ def addHeader(name, value): """Add an HTTP Header Sets a new HTTP return header with the given value, while retaining any previously set headers with the same name. """ def getHeader(name, default=None): """Gets a header value Returns the value associated with a HTTP return header, or 'default' if no such header has been set in the response yet. """ def getHeaders(): """Returns a list of header name, value tuples. """ def appendToCookie(name, value): """Append text to a cookie value If a value for the cookie has previously been set, the new value is appended to the old one separated by a colon. """ def expireCookie(name, **kw): """Causes an HTTP cookie to be removed from the browser The response will include an HTTP header that will remove the cookie corresponding to "name" on the client, if one exists. This is accomplished by sending a new cookie with an expiration date that has already passed. Note that some clients require a path to be specified - this path must exactly match the path given when creating the cookie. The path can be specified as a keyword argument. If the value of a keyword argument is None, it will be ignored. """ def setCookie(name, value, **kw): """Sets an HTTP cookie on the browser The response will include an HTTP header that sets a cookie on cookie-enabled browsers with a key "name" and value "value". This overwrites any previously set value for the cookie in the Response object. If the value of a keyword argument is None, it will be ignored. """ def getCookie(name, default=None): """Gets HTTP cookie data as a dict Returns the dict of values associated with an HTTP cookie set in the response, or 'default' if no such cookie has been set in the response yet. """ def setResult(result): """Sets response result value based on input. Input is usually a unicode string, a string, None, or an object that can be adapted to IResult with the request. The end result is an iterable such as WSGI prefers, determined by following the process described below. Try to adapt the given input, with the request, to IResult (found above in this file). If this fails, and the original value was a string, use the string as the result; or if was None, use an empty string as the result; and if it was anything else, raise a TypeError. If the result of the above (the adaptation or the default handling of string and None) is unicode, encode it (to the preferred encoding found by adapting the request to zope.i18n.interfaces.IUserPreferredCharsets, usually implemented by looking at the HTTP Accept-Charset header in the request, and defaulting to utf-8) and set the proper encoding information on the Content-Type header, if present. Otherwise (the end result was not unicode) application is responsible for setting Content-Type header encoding value as necessary. If the result of the above is a string, set the Content-Length header, and make the string be the single member of an iterable such as a tuple (to send large chunks over the wire; see discussion in the IResult interface). Otherwise (the end result was not a string) application is responsible for setting Content-Length header as necessary. Set the result of all of the above as the response's result. If the status has not been set, set it to 200 (OK). """ def consumeBody(): """Returns the response body as a string. Note that this function can be only requested once, since it is constructed from the result. """ def consumeBodyIter(): """Returns the response body as an iterable. Note that this function can be only requested once, since it is constructed from the result. """
[docs]class IHTTPVirtualHostChangedEvent(Interface): """The host, port and/or the application path have changed. The request referred to in this event implements at least the IHTTPAppliationRequest interface. """ request = Attribute(_u("The application request whose virtual host info has " "been altered"))
[docs]class IHTTPException(Interface): """Marker interface for http exceptions views """ pass
[docs]class IMethodNotAllowed(IException): """An exception that signals the 405 Method Not Allowed HTTP error""" object = Attribute("""The object on which the error occurred""") request = Attribute("""The request in which the error occurred""")
[docs]class MethodNotAllowed(Exception): """An exception that signals the 405 Method Not Allowed HTTP error""" def __init__(self, object, request): self.object = object self.request = request def __str__(self): return "%r, %r" % (self.object, self.request)