HTTP API
Vault has an HTTP API that can be used to control every aspect of Vault.
The Vault HTTP API gives you full access to Vault using REST like HTTP verbs. Every aspect of Vault can be controlled using the APIs. The Vault CLI uses the HTTP API to access Vault similar to all other consumers.
All API routes are prefixed with /v1/
.
This documentation is only for the v1 API, which is currently the only version.
Backwards compatibility: At the current version, Vault does not yet
promise backwards compatibility even with the v1 prefix. We'll remove this
warning when this policy changes. At this point in time the core API (that
is, sys/
routes) change very infrequently, but various secrets engines/auth
methods/etc. sometimes have minor changes to accommodate new features as
they're developed.
Transport
The API is expected to be accessed over a TLS connection at all times, with a valid certificate that is verified by a well-behaved client. It is possible to disable TLS verification for listeners, however, so API clients should expect to have to do both depending on user settings.
Authentication
Once Vault is unsealed, almost every other operation requires a client token.
A user may have a client token sent to them. The client token must be sent as
either the X-Vault-Token
HTTP Header or as Authorization
HTTP Header using
the Bearer <token>
scheme.
Otherwise, a client token can be retrieved using an authentication engine.
Each auth method has one or more unauthenticated login endpoints. These endpoints can be reached without any authentication, and are used for authentication to Vault itself. These endpoints are specific to each auth method.
Responses from auth login methods that generate an authentication token are
sent back to the client in JSON. The resulting token should be saved on the
client or passed via the X-Vault-Token
or Authorization
header for future requests.
Parameter restrictions
Several Vault APIs require specifying path parameters. The path parameter cannot end in periods. Otherwise, Vault will return a 404 unsupported path error.
Namespaces
When using Namespaces the final path of the API
request is relative to the X-Vault-Namespace
header. For instance, if a
request URI is secret/foo
with the X-Vault-Namespace
header set as ns1/ns2/
,
then the resulting request path to Vault will be ns1/ns2/secret/foo
.
Note that it is semantically equivalent to use the full path rather than the
X-Vault-Namespace
header, Vault will match the corresponding namespace
based on correlating user input. Similar path results may be achieved if
X-Vault-Namespace
is set to ns1/
with the request path of ns2/secret/foo
as well, or otherwise if X-Vault-Namespace
is omitted entirely and instead a
complete path is provided such as: ns1/ns2/secret/foo
.
For example, the following two commands result in equivalent requests:
API operations
Typically the request data, body and response data to and from Vault is in JSON.
Vault sets the Content-Type
header appropriately with its response and does
not require it from the clients request.
The demonstration below uses the KVv1
secrets engine, which is a
simple Key Value store. Please read the API documentation of KV secret engines
for details of KVv1
compared to KVv2
and how they differ in their URI paths
as well as the features available in version 2 of the KV secrets engine.
For KVv1
, reading a secret using the HTTP API is done by issuing a GET:
This maps to secret/foo
where foo
is the key in the secret/
mount, which
is mounted by default on a fresh Vault install and is of type kv
.
Here is an example of reading a secret using cURL:
A few endpoints consume calls with GET
query string parameters, but only if
those parameters are not sensitive, especially since some load balancers will
be able log these. Most endpoints that accept POST
query string parameters
expect those parameters in the request body.
You can list secrets as well. To do this, either issue a GET
with the query
string parameter list=true
, or you use the LIST
HTTP verb. For the kv
secrets
engine, listing is allowed on directories only, which returns the keys at the
requested path:
The API documentation uses LIST
as the HTTP verb, but you can still use GET
with the ?list=true
query string.
To make an API with specific data in request body, issue a POST
:
with a JSON body like:
Here is an example of writing a secret using cURL:
Vault currently considers PUT
and POST
to be synonyms. Rather than trust a
client's stated intentions, Vault engines can implement an existence check to
discover whether an operation is actually a create or update operation based on
the data already stored within Vault. This makes permission management via ACLs
more flexible.
A KVv2 example for the engine path of secret
requires that URI is
appended with data/
prior to the secret name (baz
) such as:
For more examples, please look at the Vault API client.
The X-Vault-Request
header
Requests that are sent to a Vault Proxy that is configured to use the
require_request_header
option must include the X-Vault-Request
header
entry, e.g.:
The Vault CLI always adds this header to every request, regardless of whether the request is being sent to a Vault Agent or directly to a Vault Server. In addition, the Vault SDK always adds this header to every request.
Help
To retrieve the help for any API within Vault, including mounted engines, auth
methods, etc. then append ?help=1
to any URL. If you have valid permission to
access the path, then the help text will be returned as a markdown-formatted block
in the help
attribute of the response.
Additionally, with the OpenAPI generation in Vault, you will get back a small
OpenAPI document in the openapi
attribute. This document is relevant for the
path you're looking up and any paths under it - also note paths in the OpenAPI
document are relative to the initial path queried.
Example request:
Example response:
Error response
A common JSON structure is always returned to return errors:
This structure will be returned for any HTTP status greater than or equal to 400.
HTTP status codes
The following HTTP status codes are used throughout the API. Vault tries to adhere to these whenever possible, but in case it doesn't -- then feel free to raise a bug for our attention!
Note: Applications should be prepared to accept both 200
and 204
as
success. 204
is simply an indication that there is no response body to parse,
but API endpoints that indicate that they return a 204
may return a 200
if
warnings are generated during the operation.
200
- Success with data.204
- Success, no data returned.400
- Invalid request, missing or invalid data.403
- Forbidden, your authentication details are either incorrect, you don't have access to this feature, or - if CORS is enabled - you made a cross-origin request from an origin that is not allowed to make such requests.404
- Invalid path. This can both mean that the path truly doesn't exist or that you don't have permission to view a specific path. We use 404 in some cases to avoid state leakage. LIST requests with no results will also return 404s.405
- Unsupported operation. You tried to use a method inappropriate to the request path, e.g. a POST on an endpoint that only accepts GETs.412
- Precondition failed. Returned on Enterprise when a request can't be processed yet due to some missing eventually consistent data. Should be retried, perhaps with a little backoff. See Vault Eventual Consistency.429
- Default return code for health status of standby nodes. This will likely change in the future.472
- Default return code for disaster recovery mode replication secondary and active.473
- Default return code for health status of performance standby nodes.500
- Internal server error. An internal error has occurred, try again later. If the error persists, report a bug.501
- Vault is not initialized.502
- A request to Vault required Vault making a request to a third party; the third party responded with an error of some kind.503
- Vault is down for maintenance or is currently sealed. Try again later.
Limits
A maximum request size of 32MB is imposed to prevent a denial of service attack
with arbitrarily large requests; this can be tuned per listener
block in
Vault's server configuration file.