»HTTP API Structure
The main interface to Consul is a RESTful HTTP API. The API can perform basic CRUD operations on nodes, services, checks, configuration, and more.
When authentication is enabled, a Consul token should be provided to API
requests using the
X-Consul-Token header or with the
Bearer scheme in the authorization header.
This reduces the probability of the
token accidentally getting logged or exposed. When using authentication,
clients should communicate via TLS. If you don’t provide a token in the request, then the agent default token will be used.
Below is an example using
$ curl \ --header "X-Consul-Token: <consul token>" \ http://127.0.0.1:8500/v1/agent/members
Below is an example using
curl with Bearer scheme.
$ curl \ --header "Authorization: Bearer <consul token>" \ http://127.0.0.1:8500/v1/agent/members
Previously this was provided via a
?token= query parameter. This functionality
exists on many endpoints for backwards compatibility, but its use is highly
discouraged, since it can show up in access logs as part of the URL.
To learn more about the ACL system read the documentation.
All API routes are prefixed with
/v1/. This documentation is only for the v1 API.
»Formatted JSON Output
By default, the output of all HTTP API requests is minimized JSON. If the client
pretty on the query string, formatted JSON will be returned.
Consul's API aims to be RESTful, although there are some exceptions. The API responds to the standard HTTP verbs GET, PUT, and DELETE. Each API method will clearly document the verb(s) it responds to and the generated response. The same path with different verbs may trigger different behavior. For example:
PUT /v1/kv/fooGET /v1/kv/foo
Even though these share a path, the
PUT operation creates a new key whereas
GET operation reads an existing key.
Here is the same example using
$ curl \ --request PUT \ --data 'hello consul' \ http://127.0.0.1:8500/v1/kv/foo
Consul 0.7 added the ability to translate addresses in HTTP response based on
the configuration setting for
translate_wan_addrs. In order
to allow clients to know if address translation is in effect, the
X-Consul-Translate-Addresses header will be added if translation is enabled,
and will have a value of
true. If translation is not enabled then this header
will not be present.
»Default ACL Policy
All API responses for Consul versions after 1.9 will include an HTTP response
X-Consul-Default-ACL-Policy set to either "allow" or "deny" which
mirrors the current value of the agent's
This is also the default intention enforcement action if no intention matches.
This is returned even if ACLs are disabled.
»Results Filtered by ACLs
As of Consul 1.11, most list endpoints support an
HTTP response header. This indicates that the response contains a partial subset
of results, because some have been filtered out by ACL policies.
In order to limit information leakage, this header is only present for requests authenticated by a valid ACL token.
UUID-format identifiers generated by the Consul API use the hashicorp/go-uuid library.
These UUID-format strings are generated using high quality, purely random bytes. It is not intended to be RFC compliant, merely to use a well-understood string representation of a 128-bit value.