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604 lines
28 KiB
604 lines
28 KiB
;; (in-package :cl-user) |
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(defpackage #:status-code |
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(:use :cl) |
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(:nicknames #:rfc2616-sec10) |
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(:export +continue+ |
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+switching-protocols+ |
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+ok+ |
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+created+ |
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+accepted+ |
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+non-authoritative-information+ |
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+no-content+ |
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+reset-content+ |
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+partial-content+ |
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+multiple-choices+ |
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+moved-permanently+ |
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+found+ |
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+see-other+ |
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+not-modified+ |
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+use-proxy+ |
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+temporary-redirect+ |
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+bad-request+ |
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+unauthorized+ |
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+payment-required+ |
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+forbidden+ |
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+not-found+ |
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+method-not-allowed+ |
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+not-acceptable+ |
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+proxy-authentication-required+ |
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+request-timeout+ |
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+conflict+ |
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+gone+ |
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+length-required+ |
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+precondition-failed+ |
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+request-entity-too-large+ |
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+request-uri-too-long+ |
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+unsupported-media-type+ |
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+requested-range-not-satisfiable+ |
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+expectation-failed+ |
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+internal-server-error+ |
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+not-implemented+ |
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+bad-gateway+ |
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+service-unavailable+ |
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+gateway-timeout+ |
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+http-version-not-supported+)) |
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(in-package #:status-code) |
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|
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;;rfc2616-sec10) |
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|
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(DEFCONSTANT +CONTINUE+ |
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100 |
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"The client SHOULD continue with its request. This interim response is |
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used to inform the client that the initial part of the request has |
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been received and has not yet been rejected by the server. The client |
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SHOULD continue by sending the remainder of the request or, if the |
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request has already been completed, ignore this response. The server |
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MUST send a final response after the request has been completed. See |
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section 8.2.3 for detailed discussion of the use and handling of this |
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status code.") |
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|
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(DEFCONSTANT +SWITCHING-PROTOCOLS+ |
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101 |
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"The server understands and is willing to comply with the client's |
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request, via the Upgrade message header field (section 14.42), for a |
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change in the application protocol being used on this connection. The |
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server will switch protocols to those defined by the response's |
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Upgrade header field immediately after the empty line which |
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terminates the 101 response. |
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|
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The protocol SHOULD be switched only when it is advantageous to do |
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so. For example, switching to a newer version of HTTP is advantageous |
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over older versions, and switching to a real-time, synchronous |
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protocol might be advantageous when delivering resources that use |
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such features.") |
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|
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(DEFCONSTANT +OK+ |
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200 |
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"The request has succeeded. The information returned with the response |
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is dependent on the method used in the request, for example: |
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|
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GET an entity corresponding to the requested resource is sent in |
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the response; |
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|
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HEAD the entity-header fields corresponding to the requested |
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resource are sent in the response without any message-body; |
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|
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POST an entity describing or containing the result of the action; |
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|
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TRACE an entity containing the request message as received by the |
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end server.") |
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|
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(DEFCONSTANT +CREATED+ |
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201 |
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"The request has been fulfilled and resulted in a new resource being |
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created. The newly created resource can be referenced by the URI(s) |
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returned in the entity of the response, with the most specific URI |
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for the resource given by a Location header field. The response |
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SHOULD include an entity containing a list of resource |
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characteristics and location(s) from which the user or user agent can |
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choose the one most appropriate. The entity format is specified by |
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the media type given in the Content-Type header field. The origin |
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server MUST create the resource before returning the 201 status code. |
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If the action cannot be carried out immediately, the server SHOULD |
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respond with 202 (Accepted) response instead. |
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|
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A 201 response MAY contain an ETag response header field indicating |
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the current value of the entity tag for the requested variant just |
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created, see section 14.19.") |
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|
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(DEFCONSTANT +ACCEPTED+ |
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202 |
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"The request has been accepted for processing, but the processing has |
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not been completed. The request might or might not eventually be |
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acted upon, as it might be disallowed when processing actually takes |
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place. There is no facility for re-sending a status code from an |
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asynchronous operation such as this. |
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|
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The 202 response is intentionally non-committal. Its purpose is to |
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allow a server to accept a request for some other process (perhaps a |
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batch-oriented process that is only run once per day) without |
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requiring that the user agent's connection to the server persist |
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until the process is completed. The entity returned with this |
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response SHOULD include an indication of the request's current status |
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and either a pointer to a status monitor or some estimate of when the |
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user can expect the request to be fulfilled.") |
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|
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(DEFCONSTANT +NON-AUTHORITATIVE-INFORMATION+ |
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203 |
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"The returned metainformation in the entity-header is not the |
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definitive set as available from the origin server, but is gathered |
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from a local or a third-party copy. The set presented MAY be a subset |
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or superset of the original version. For example, including local |
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annotation information about the resource might result in a superset |
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of the metainformation known by the origin server. Use of this |
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response code is not required and is only appropriate when the |
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response would otherwise be 200 (OK).") |
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|
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(DEFCONSTANT +NO-CONTENT+ |
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204 |
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"The server has fulfilled the request but does not need to return an |
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entity-body, and might want to return updated metainformation. The |
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response MAY include new or updated metainformation in the form of |
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entity-headers, which if present SHOULD be associated with the |
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requested variant. |
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|
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If the client is a user agent, it SHOULD NOT change its document view |
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from that which caused the request to be sent. This response is |
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primarily intended to allow input for actions to take place without |
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causing a change to the user agent's active document view, although |
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any new or updated metainformation SHOULD be applied to the document |
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currently in the user agent's active view. |
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|
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The 204 response MUST NOT include a message-body, and thus is always |
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terminated by the first empty line after the header fields.") |
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|
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(DEFCONSTANT +RESET-CONTENT+ |
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205 |
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"The server has fulfilled the request and the user agent SHOULD reset |
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the document view which caused the request to be sent. This response |
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is primarily intended to allow input for actions to take place via |
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user input, followed by a clearing of the form in which the input is |
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given so that the user can easily initiate another input action. The |
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response MUST NOT include an entity.") |
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|
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(DEFCONSTANT +PARTIAL-CONTENT+ |
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206 |
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"The server has fulfilled the partial GET request for the resource. |
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The request MUST have included a Range header field (section 14.35) |
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indicating the desired range, and MAY have included an If-Range |
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header field (section 14.27) to make the request conditional. |
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The response MUST include the following header fields: |
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- Either a Content-Range header field (section 14.16) indicating |
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the range included with this response, or a multipart/byteranges |
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Content-Type including Content-Range fields for each part. If a |
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Content-Length header field is present in the response, its |
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value MUST match the actual number of OCTETs transmitted in the |
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message-body. |
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- Date |
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- ETag and/or Content-Location, if the header would have been sent |
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in a 200 response to the same request |
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- Expires, Cache-Control, and/or Vary, if the field-value might |
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differ from that sent in any previous response for the same |
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variant |
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If the 206 response is the result of an If-Range request that used a |
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strong cache validator (see section 13.3.3), the response SHOULD NOT |
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include other entity-headers. If the response is the result of an |
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If-Range request that used a weak validator, the response MUST NOT |
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include other entity-headers; this prevents inconsistencies between |
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cached entity-bodies and updated headers. Otherwise, the response |
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MUST include all of the entity-headers that would have been returned |
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with a 200 (OK) response to the same request. |
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|
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A cache MUST NOT combine a 206 response with other previously cached |
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content if the ETag or Last-Modified headers do not match exactly, |
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see 13.5.4. |
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A cache that does not support the Range and Content-Range headers |
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MUST NOT cache 206 (Partial) responses.") |
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|
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(DEFCONSTANT +MULTIPLE-CHOICES+ |
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300 |
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"The requested resource corresponds to any one of a set of |
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representations, each with its own specific location, and agent- |
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driven negotiation information (section 12) is being provided so that |
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the user (or user agent) can select a preferred representation and |
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redirect its request to that location. |
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|
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Unless it was a HEAD request, the response SHOULD include an entity |
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containing a list of resource characteristics and location(s) from |
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which the user or user agent can choose the one most appropriate. The |
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entity format is specified by the media type given in the Content- |
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Type header field. Depending upon the format and the capabilities of |
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|
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the user agent, selection of the most appropriate choice MAY be |
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performed automatically. However, this specification does not define |
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any standard for such automatic selection. |
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|
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If the server has a preferred choice of representation, it SHOULD |
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include the specific URI for that representation in the Location |
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field; user agents MAY use the Location field value for automatic |
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redirection. This response is cacheable unless indicated otherwise.") |
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(DEFCONSTANT +MOVED-PERMANENTLY+ |
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301 |
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"The requested resource has been assigned a new permanent URI and any |
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future references to this resource SHOULD use one of the returned |
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URIs. Clients with link editing capabilities ought to automatically |
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re-link references to the Request-URI to one or more of the new |
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references returned by the server, where possible. This response is |
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cacheable unless indicated otherwise. |
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The new permanent URI SHOULD be given by the Location field in the |
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response. Unless the request method was HEAD, the entity of the |
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response SHOULD contain a short hypertext note with a hyperlink to |
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the new URI(s). |
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If the 301 status code is received in response to a request other |
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than GET or HEAD, the user agent MUST NOT automatically redirect the |
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request unless it can be confirmed by the user, since this might |
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change the conditions under which the request was issued. |
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Note: When automatically redirecting a POST request after |
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receiving a 301 status code, some existing HTTP/1.0 user agents |
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will erroneously change it into a GET request.") |
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|
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(DEFCONSTANT +FOUND+ |
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302 |
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"The requested resource resides temporarily under a different URI. |
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Since the redirection might be altered on occasion, the client SHOULD |
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continue to use the Request-URI for future requests. This response |
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is only cacheable if indicated by a Cache-Control or Expires header |
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field. |
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|
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The temporary URI SHOULD be given by the Location field in the |
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response. Unless the request method was HEAD, the entity of the |
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response SHOULD contain a short hypertext note with a hyperlink to |
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the new URI(s). |
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If the 302 status code is received in response to a request other |
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than GET or HEAD, the user agent MUST NOT automatically redirect the |
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request unless it can be confirmed by the user, since this might |
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change the conditions under which the request was issued. |
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Note: RFC 1945 and RFC 2068 specify that the client is not allowed |
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to change the method on the redirected request. However, most |
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existing user agent implementations treat 302 as if it were a 303 |
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response, performing a GET on the Location field-value regardless |
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of the original request method. The status codes 303 and 307 have |
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been added for servers that wish to make unambiguously clear which |
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kind of reaction is expected of the client.") |
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(DEFCONSTANT +SEE-OTHER+ |
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303 |
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"The response to the request can be found under a different URI and |
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SHOULD be retrieved using a GET method on that resource. This method |
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exists primarily to allow the output of a POST-activated script to |
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redirect the user agent to a selected resource. The new URI is not a |
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substitute reference for the originally requested resource. The 303 |
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response MUST NOT be cached, but the response to the second |
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(redirected) request might be cacheable. |
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|
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The different URI SHOULD be given by the Location field in the |
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response. Unless the request method was HEAD, the entity of the |
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response SHOULD contain a short hypertext note with a hyperlink to |
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the new URI(s). |
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Note: Many pre-HTTP/1.1 user agents do not understand the 303 |
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status. When interoperability with such clients is a concern, the |
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302 status code may be used instead, since most user agents react |
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to a 302 response as described here for 303.") |
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|
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(DEFCONSTANT +NOT-MODIFIED+ |
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304 |
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"If the client has performed a conditional GET request and access is |
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allowed, but the document has not been modified, the server SHOULD |
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respond with this status code. The 304 response MUST NOT contain a |
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message-body, and thus is always terminated by the first empty line |
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after the header fields. |
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|
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The response MUST include the following header fields: |
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- Date, unless its omission is required by section 14.18.1 |
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|
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If a clockless origin server obeys these rules, and proxies and |
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clients add their own Date to any response received without one (as |
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already specified by [RFC 2068], section 14.19), caches will operate |
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correctly. |
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- ETag and/or Content-Location, if the header would have been sent |
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in a 200 response to the same request |
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- Expires, Cache-Control, and/or Vary, if the field-value might |
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differ from that sent in any previous response for the same |
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variant |
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|
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If the conditional GET used a strong cache validator (see section |
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13.3.3), the response SHOULD NOT include other entity-headers. |
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Otherwise (i.e., the conditional GET used a weak validator), the |
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response MUST NOT include other entity-headers; this prevents |
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inconsistencies between cached entity-bodies and updated headers. |
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|
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If a 304 response indicates an entity not currently cached, then the |
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cache MUST disregard the response and repeat the request without the |
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conditional. |
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|
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If a cache uses a received 304 response to update a cache entry, the |
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cache MUST update the entry to reflect any new field values given in |
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the response.") |
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(DEFCONSTANT +USE-PROXY+ |
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305 |
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"The requested resource MUST be accessed through the proxy given by |
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the Location field. The Location field gives the URI of the proxy. |
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The recipient is expected to repeat this single request via the |
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proxy. 305 responses MUST only be generated by origin servers. |
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Note: RFC 2068 was not clear that 305 was intended to redirect a |
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single request, and to be generated by origin servers only. Not |
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observing these limitations has significant security consequences.") |
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(DEFCONSTANT +TEMPORARY-REDIRECT+ |
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307 |
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"The requested resource resides temporarily under a different URI. |
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Since the redirection MAY be altered on occasion, the client SHOULD |
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continue to use the Request-URI for future requests. This response |
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is only cacheable if indicated by a Cache-Control or Expires header |
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field. |
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|
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The temporary URI SHOULD be given by the Location field in the |
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response. Unless the request method was HEAD, the entity of the |
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response SHOULD contain a short hypertext note with a hyperlink to |
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the new URI(s) , since many pre-HTTP/1.1 user agents do not |
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understand the 307 status. Therefore, the note SHOULD contain the |
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information necessary for a user to repeat the original request on |
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the new URI. |
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If the 307 status code is received in response to a request other |
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than GET or HEAD, the user agent MUST NOT automatically redirect the |
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request unless it can be confirmed by the user, since this might |
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change the conditions under which the request was issued.") |
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|
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(DEFCONSTANT +BAD-REQUEST+ |
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400 |
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"The request could not be understood by the server due to malformed |
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syntax. The client SHOULD NOT repeat the request without |
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modifications.") |
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(DEFCONSTANT +UNAUTHORIZED+ |
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401 |
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"The request requires user authentication. The response MUST include a |
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WWW-Authenticate header field (section 14.47) containing a challenge |
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applicable to the requested resource. The client MAY repeat the |
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request with a suitable Authorization header field (section 14.8). If |
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the request already included Authorization credentials, then the 401 |
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response indicates that authorization has been refused for those |
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credentials. If the 401 response contains the same challenge as the |
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prior response, and the user agent has already attempted |
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authentication at least once, then the user SHOULD be presented the |
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entity that was given in the response, since that entity might |
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include relevant diagnostic information. HTTP access authentication |
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is explained in \"HTTP Authentication: Basic and Digest Access |
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Authentication\" [43].") |
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(DEFCONSTANT +PAYMENT-REQUIRED+ 402 "This code is reserved for future use.") |
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|
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(DEFCONSTANT +FORBIDDEN+ |
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403 |
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"The server understood the request, but is refusing to fulfill it. |
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Authorization will not help and the request SHOULD NOT be repeated. |
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If the request method was not HEAD and the server wishes to make |
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public why the request has not been fulfilled, it SHOULD describe the |
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reason for the refusal in the entity. If the server does not wish to |
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make this information available to the client, the status code 404 |
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(Not Found) can be used instead.") |
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|
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(DEFCONSTANT +NOT-FOUND+ |
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404 |
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"The server has not found anything matching the Request-URI. No |
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indication is given of whether the condition is temporary or |
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permanent. The 410 (Gone) status code SHOULD be used if the server |
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knows, through some internally configurable mechanism, that an old |
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resource is permanently unavailable and has no forwarding address. |
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This status code is commonly used when the server does not wish to |
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reveal exactly why the request has been refused, or when no other |
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response is applicable.") |
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(DEFCONSTANT +METHOD-NOT-ALLOWED+ |
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405 |
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"The method specified in the Request-Line is not allowed for the |
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resource identified by the Request-URI. The response MUST include an |
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Allow header containing a list of valid methods for the requested |
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resource.") |
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|
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(DEFCONSTANT +NOT-ACCEPTABLE+ |
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406 |
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"The resource identified by the request is only capable of generating |
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response entities which have content characteristics not acceptable |
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according to the accept headers sent in the request. |
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|
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Unless it was a HEAD request, the response SHOULD include an entity |
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containing a list of available entity characteristics and location(s) |
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from which the user or user agent can choose the one most |
|
appropriate. The entity format is specified by the media type given |
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in the Content-Type header field. Depending upon the format and the |
|
capabilities of the user agent, selection of the most appropriate |
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choice MAY be performed automatically. However, this specification |
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does not define any standard for such automatic selection. |
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Note: HTTP/1.1 servers are allowed to return responses which are |
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not acceptable according to the accept headers sent in the |
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request. In some cases, this may even be preferable to sending a |
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406 response. User agents are encouraged to inspect the headers of |
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an incoming response to determine if it is acceptable. |
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|
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If the response could be unacceptable, a user agent SHOULD |
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temporarily stop receipt of more data and query the user for a |
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decision on further actions.") |
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|
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(DEFCONSTANT +PROXY-AUTHENTICATION-REQUIRED+ |
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407 |
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"This code is similar to 401 (Unauthorized), but indicates that the |
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client must first authenticate itself with the proxy. The proxy MUST |
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return a Proxy-Authenticate header field (section 14.33) containing a |
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challenge applicable to the proxy for the requested resource. The |
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client MAY repeat the request with a suitable Proxy-Authorization |
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header field (section 14.34). HTTP access authentication is explained |
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in \"HTTP Authentication: Basic and Digest Access Authentication\" |
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[43].") |
|
|
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(DEFCONSTANT +REQUEST-TIMEOUT+ |
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408 |
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"The client did not produce a request within the time that the server |
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was prepared to wait. The client MAY repeat the request without |
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modifications at any later time.") |
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|
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(DEFCONSTANT +CONFLICT+ |
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409 |
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"The request could not be completed due to a conflict with the current |
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state of the resource. This code is only allowed in situations where |
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it is expected that the user might be able to resolve the conflict |
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and resubmit the request. The response body SHOULD include enough |
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|
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information for the user to recognize the source of the conflict. |
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Ideally, the response entity would include enough information for the |
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user or user agent to fix the problem; however, that might not be |
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possible and is not required. |
|
|
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Conflicts are most likely to occur in response to a PUT request. For |
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example, if versioning were being used and the entity being PUT |
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included changes to a resource which conflict with those made by an |
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earlier (third-party) request, the server might use the 409 response |
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to indicate that it can't complete the request. In this case, the |
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response entity would likely contain a list of the differences |
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between the two versions in a format defined by the response |
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Content-Type.") |
|
|
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(DEFCONSTANT +GONE+ |
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410 |
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"The requested resource is no longer available at the server and no |
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forwarding address is known. This condition is expected to be |
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considered permanent. Clients with link editing capabilities SHOULD |
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delete references to the Request-URI after user approval. If the |
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server does not know, or has no facility to determine, whether or not |
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the condition is permanent, the status code 404 (Not Found) SHOULD be |
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used instead. This response is cacheable unless indicated otherwise. |
|
|
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The 410 response is primarily intended to assist the task of web |
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maintenance by notifying the recipient that the resource is |
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intentionally unavailable and that the server owners desire that |
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remote links to that resource be removed. Such an event is common for |
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limited-time, promotional services and for resources belonging to |
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individuals no longer working at the server's site. It is not |
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necessary to mark all permanently unavailable resources as \"gone\" or |
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to keep the mark for any length of time -- that is left to the |
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discretion of the server owner.") |
|
|
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(DEFCONSTANT +LENGTH-REQUIRED+ |
|
411 |
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"The server refuses to accept the request without a defined Content- |
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Length. The client MAY repeat the request if it adds a valid |
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Content-Length header field containing the length of the message-body |
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in the request message.") |
|
|
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(DEFCONSTANT +PRECONDITION-FAILED+ |
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412 |
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"The precondition given in one or more of the request-header fields |
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evaluated to false when it was tested on the server. This response |
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code allows the client to place preconditions on the current resource |
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metainformation (header field data) and thus prevent the requested |
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method from being applied to a resource other than the one intended.") |
|
|
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(DEFCONSTANT +REQUEST-ENTITY-TOO-LARGE+ |
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413 |
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"The server is refusing to process a request because the request |
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entity is larger than the server is willing or able to process. The |
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server MAY close the connection to prevent the client from continuing |
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the request. |
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|
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If the condition is temporary, the server SHOULD include a Retry- |
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After header field to indicate that it is temporary and after what |
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time the client MAY try again.") |
|
|
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(DEFCONSTANT +REQUEST-URI-TOO-LONG+ |
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414 |
|
"The server is refusing to service the request because the Request-URI |
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is longer than the server is willing to interpret. This rare |
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condition is only likely to occur when a client has improperly |
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converted a POST request to a GET request with long query |
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information, when the client has descended into a URI \"black hole\" of |
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redirection (e.g., a redirected URI prefix that points to a suffix of |
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itself), or when the server is under attack by a client attempting to |
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exploit security holes present in some servers using fixed-length |
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buffers for reading or manipulating the Request-URI.") |
|
|
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(DEFCONSTANT +UNSUPPORTED-MEDIA-TYPE+ |
|
415 |
|
"The server is refusing to service the request because the entity of |
|
the request is in a format not supported by the requested resource |
|
for the requested method.") |
|
|
|
(DEFCONSTANT +REQUESTED-RANGE-NOT-SATISFIABLE+ |
|
416 |
|
"A server SHOULD return a response with this status code if a request |
|
included a Range request-header field (section 14.35), and none of |
|
the range-specifier values in this field overlap the current extent |
|
of the selected resource, and the request did not include an If-Range |
|
request-header field. (For byte-ranges, this means that the first- |
|
byte-pos of all of the byte-range-spec values were greater than the |
|
current length of the selected resource.) |
|
|
|
When this status code is returned for a byte-range request, the |
|
response SHOULD include a Content-Range entity-header field |
|
specifying the current length of the selected resource (see section |
|
14.16). This response MUST NOT use the multipart/byteranges content- |
|
type.") |
|
|
|
(DEFCONSTANT +EXPECTATION-FAILED+ |
|
417 |
|
"The expectation given in an Expect request-header field (see section |
|
14.20) could not be met by this server, or, if the server is a proxy, |
|
the server has unambiguous evidence that the request could not be met |
|
by the next-hop server.") |
|
|
|
(DEFCONSTANT +INTERNAL-SERVER-ERROR+ |
|
500 |
|
"The server encountered an unexpected condition which prevented it |
|
from fulfilling the request.") |
|
|
|
(DEFCONSTANT +NOT-IMPLEMENTED+ |
|
501 |
|
"The server does not support the functionality required to fulfill the |
|
request. This is the appropriate response when the server does not |
|
recognize the request method and is not capable of supporting it for |
|
any resource.") |
|
|
|
(DEFCONSTANT +BAD-GATEWAY+ |
|
502 |
|
"The server, while acting as a gateway or proxy, received an invalid |
|
response from the upstream server it accessed in attempting to |
|
fulfill the request.") |
|
|
|
(DEFCONSTANT +SERVICE-UNAVAILABLE+ |
|
503 |
|
"The server is currently unable to handle the request due to a |
|
temporary overloading or maintenance of the server. The implication |
|
is that this is a temporary condition which will be alleviated after |
|
some delay. If known, the length of the delay MAY be indicated in a |
|
Retry-After header. If no Retry-After is given, the client SHOULD |
|
handle the response as it would for a 500 response. |
|
Note: The existence of the 503 status code does not imply that a |
|
server must use it when becoming overloaded. Some servers may wish |
|
to simply refuse the connection.") |
|
|
|
(DEFCONSTANT +GATEWAY-TIMEOUT+ |
|
504 |
|
"The server, while acting as a gateway or proxy, did not receive a |
|
timely response from the upstream server specified by the URI (e.g. |
|
HTTP, FTP, LDAP) or some other auxiliary server (e.g. DNS) it needed |
|
to access in attempting to complete the request. |
|
Note: Note to implementors: some deployed proxies are known to |
|
return 400 or 500 when DNS lookups time out.") |
|
|
|
(DEFCONSTANT +HTTP-VERSION-NOT-SUPPORTED+ |
|
505 |
|
"The server does not support, or refuses to support, the HTTP protocol |
|
version that was used in the request message. The server is |
|
indicating that it is unable or unwilling to complete the request |
|
using the same major version as the client, as described in section |
|
3.1, other than with this error message. The response SHOULD contain |
|
an entity describing why that version is not supported and what other |
|
protocols are supported by that server.")
|
|
|