Headers

This article provides links to reference pages for headers used with the Azure App Configuration REST API.

Request Headers

The following table describes common request headers used in Azure App Configuration.

Header Description Example
Authorization Used to authenticate a request to the service. See section 14.8 Authorization: HMAC-SHA256 Credential=<Credential>&SignedHeaders=Host;x-ms-date;x-ms-content-sha256&Signature=<Signature>
Accept Informs the server what media type the client will accept in an HTTP response. See section 14.1 Accept: application/vnd.microsoft.appconfig.kv+json;
Accept-Datetime Requests the server to return its content as a representation of its prior state. The value of this header is the requested datetime of that state. See RFC 7089 Accept-Datetime: Sat, 12 May 2018 02:10:00 GMT
Content-Type Contains the media-type of the content within the HTTP request body. See section 14.17 Content-Type: application/vnd.microsoft.appconfig.kv+json; charset=utf-8;
Date The datetime that the HTTP request was issued. This header is used in HMAC authentication. See section 14.18 Date: Fri, 11 May 2018 18:48:36 GMT
Host Specifies the tenant for which the request has been issued. This header is used in HMAC authentication. See section 14.23 Host: contoso.azconfig.io
If-Match Used to make an HTTP request conditional. This request should only succeed if the targeted resource's ETag matches the value of this header. The '*' value matches any ETag. See section 14.24 If-Match: "4f6dd610dd5e4deebc7fbaef685fb903"
If-None-Match Used to make an HTTP request conditional. This request should only succeed if the targeted resource's ETag does not match the value of this header. The '*' value matches any ETag. See section 14.26 If-None-Match: "4f6dd610dd5e4deebc7fbaef685fb903"
Sync-Token Used to enable real-time consistency during a sequence of requests. Sync-Token: jtqGc1I4=MDoyOA==;sn=28
x-ms-client-request-id A unique ID provided by the client used to track a request's round-trip. x-ms-client-request-id: 00000000-0000-0000-0000-000000000000
x-ms-content-sha256 A sha256 digest of the HTTP request body. This header is used in HMAC authentication. x-ms-content-sha256: 47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU=
x-ms-date This header may be set and used in place of the Date header if the date header is unable to be accessed. This header is used in HMAC authentication. x-ms-date: Fri, 11 May 2018 18:48:36 GMT
x-ms-return-client-request-id Used in conjunction with the x-ms-client-request-id header. If the value of this header is 'true', then the server will be instructed to return the value of the x-ms-client-request-id request header. x-ms-return-client-request-id: true

Response Headers

The server may include the following HTTP headers in its responses.

Header Description Example
Content-Type Contains the media-type of the content within the HTTP response body. See section 14.17 Content-Type: application/vnd.microsoft.appconfig.kv+json; charset=utf-8;
ETag An opaque token representing the state of a given resource. Can be used in conditional operations. See section 14.19 ETag: "4f6dd610dd5e4deebc7fbaef685fb903"
Last-Modified Describes when the requested resource was last modified. Formatted as an HTTP-Date. See section 14.29 Last-Modified: Tue, 05 Dec 2017 02:41:26 GMT
Link Provides links to resources that are related to the response. This header is used for paging by using the next link. See RFC 5988 Link: </kv?after={token}>; rel="next"
Memento-Datetime Indicates that the content contained in a response represents a prior state. The value of this header is the datetime of that state. See RFC 7089 Memento-Datetime: Sat, 12 May 2018 02:10:00 GMT
retry-after-ms Provides a suggested period (in milliseconds) for the client to wait before retrying a failed request. retry-after-ms: 10
x-ms-request-id A unique ID generated by the server that is used to track the request within the service. x-ms-request-id: 00000000-0000-0000-0000-000000000000
WWW-Authenticate Used to challenge clients for authentication and provide a reason as to why an authentication attempt has failed. See section 14.47 WWW-Authenticate: HMAC-SHA256 error="invalid_token" error_description="Invalid Signature"