Content-type

Specifies the content type of the information being supplied within the request. The specification uses MIME type specifications. For the majority of requests this will be JSON (application/json). For some settings the MIME type will be plain text. When uploading attachments it should be the corresponding MIME type for the attachment or binary (application/octet-stream).

The use of the Content-type on a request is highly recommended.

Accept

Specifies the list of accepted data types to be returned by the server (i.e. that are accepted/understandable by the client). The format should be a list of one or more MIME types, separated by colons.

For the majority of requests the definition should be for JSON data (application/json). For attachments you can either specify the MIME type explicitly, or use */* to specify that all file types are supported. If the Accept header is not supplied, then the */* MIME type is assumed (i.e. client accepts all formats).

The use of Accept in queries for CouchDB is not required, but is highly recommended as it helps to ensure that the data returned can be processed by the client.

If you specify a data type using the Accept header, CouchDB will honor the specified type in the Content-type header field returned. For example, if you explicitly request application/json in the Accept of a request, the returned HTTP headers will use the value in the returned Content-type field.

For example, when sending a request without an explicit Accept header, or when specifying */*:

GET /recipes HTTP/1.1
Host: couchdb:5984
Accept: */*

The returned headers are:

Server: CouchDB/1.0.1 (Erlang OTP/R13B)
Date: Thu, 13 Jan 2011 13:39:34 GMT
Content-Type: text/plain;charset=utf-8
Content-Length: 227
Cache-Control: must-revalidate

Note that the returned content type is text/plain even though the information returned by the request is in JSON format.

Explicitly specifying the Accept header:

GET /recipes HTTP/1.1
Host: couchdb:5984
Accept: application/json

The headers returned include the application/json content type:

Server: CouchDB/1.0.1 (Erlang OTP/R13B)
Date: Thu, 13 Jan 2011 13:40:11 GMT
Content-Type: application/json
Content-Length: 227
Cache-Control: must-revalidate