HTTP Implementation

Headers

The REST API uses standard HTTP headers to decorate its requests and replies.

The following request headers are extensively used.

Name	Description
`Accept`	Indicates the desired media format. At this time, it should always be `application/json`.
`If-None-Match`	Indicates that if the `ETag` header of the resource matches any of those submitted, the request may be fulfilled with a `304 Not Modified` reply so that a locally cached version are used instead.
`Content-Type`	If the request contains content, this header indicates the media format used. At this time, only `application/json` is supported.
`X-Auth-Token`	Used to authenticate requests.
`X-Impersonate`	Used to impersonate a username.

The following returned response headers are the most common.

Name	Description
`Content-Type`	Media format used in the body of the response. At this time, only JSON is supported, so this should always return `application/json`.
`ETag`	String representation of the version returned by the resource that can be used with the `If-None-Match` header to optimize network bandwidth usage. See Caching.
`Location`	In response to creating a new resource, the server responds with `201 Created` and includes this header to provide the URL of the newly created resource.
`X-Global-Identifier`	In response to creating a new resource, the server responds with `201 Created` and includes this header information to provide the GLOBAL IDENTIFIER of the newly created resource.

Note

For brevity, these headers are not explained again in the documentation when discussing the specific details of a resource.

Example

The following example shows how to use the headers in HTTP requests:

curl --request GET \
--url https://MyInstance/api/entities/48109 \
--header 'Accept: application/json' \
--header 'Content-Type: application/json' \
--header 'X-Auth-Token: XXXXXX' \
--header 'X-Impersonate: TheUsernameToImpersonate'

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