HTTP API

Everything you need to know to work with the VerneMQ HTTP administration interface

The VerneMQ HTTP API is enabled by default and installs an HTTP handler on http://localhost:8888/api/v1. To read more about configuring the HTTP listener, see HTTP Listener Configuration. You can configure a HTTP listener, or a HTTPS listener to serve the HTTP API v1.

Managing API keys

The VerneMQ HTTP API uses basic authentication where an API key is passed as the username and the password is left empty, as an alternative the x-api-key header option can be used. API keys have a scope and (optional) can have an expiry date. So the first step to us the HTTP API is to create an API key.

Scopes

Each HTTP Module can be protected by an API key. An API key can be limited to a certain http module or further restrict some functionality within the http module. The scope used by the management API is "mgmt". Currently, the following scopes are supported "status", "mgmt", "metrics", "health".

Create API key

$ vmq-admin api-key create
JxctXkZ1OTVnlwvguSCE9KtujacMkOLF

or with scope and an expiry date (in local time)

$ vmq-admin api-key create scope=mgmt expires=2023-04-04T12:00:00
q85i5HbFCDdAVLNJuOj48QktDbchvOMS

The keys are persisted and available on all cluster nodes.

List API keys

To list existing keys do:

$ vmq-admin api-key show
+----------------------------------+-------+---------------------+-------------+
| Key                              | Scope | Expires (UTC)       | has expired |
+----------------------------------+-------+---------------------+-------------+
| q85i5HbFCDdAVLNJuOj48QktDbchvOMS | mgmt  | 2023-04-04 10:00:00 | false       |
+----------------------------------+-------+---------------------+-------------+
| JxctXkZ1OTVnlwvguSCE9KtujacMkOLF | mgmt  | never               | false       |
+----------------------------------+-------+---------------------+-------------+

Add API key

To add an API key of your own choosing, do:

vmq-admin api-key add key=mykey

Delete API key

To delete an API key do:

vmq-admin api-key delete key=JxctXkZ1OTVnlwvguSCE9KtujacMkOLF

Advanced Settings (key rotation, key complexity)

You can specifiy the minimal length of an API key (default: 0) in vernemq.conf

min_apikey_length = 30

or a set a max duration of an API key before it expires (default: undefined)

max_apikey_expiry_days = 180

Please note that changing those settings after some api keys have already been created has no influence on already created keys.

You can enable or disable API key authentication per module, or per module per listener.

http_module.$module.auth.mode 
listener.http.$name.http_module.$module.auth.mode
listener.https.$name.http_module.$module.auth.mode

Possible modules are vmq_metrics_http,vmq_http_mgmt_api, vmq_status_http, vmq_health_http. Possible values for auth.mode are noauth or apikey.

API usage

The VerneMQ HTTP API is a wrapper over the vmq-admin CLI tool, and anything that can be done using vmq-admin can be done using the HTTP API. Note that the HTTP API is therefore subject to any changes made to the vmq-admin tools and their flags & options structure. All requests are performed doing a HTTP GET and if no errors occurred an HTTP 200 OK code is returned with a possible non-empty JSON payload.

The API is using basic auth where the API key is passed as the username. An example using curl would look like this:

curl "http://JxctXkZ1OTVnlwvguSCE9KtujacMkOLF@localhost:8888/api/v1/session/show"

The mapping between vmq-admin and the HTTP API is straightforward, and if one is already familiar with how the vmq-admin tool works, working with the API should be easy. The mapping works such that the command part of a vmq-admin invocation is turned into a path, and the options and flags are turned into the query string.

A mandatory parameter like the client-id in the vmq-admin session disconnect client-id=myclient command should be translated as: ?client-id=myclient.

An optional flag like --cleanup in the vmq-admin session disconnect client-id=myclient --cleanup command should be translated as: &--cleanup

Let's look at the cluster join command as an example, which looks like this:

vmq-admin cluster join discovery-node=NodeB@10.0.0.2

This turns into a GET request:

GET /api/v1/cluster/join?discovery-node=NodeB@10.0.0.2

To test, run it with curl:

curl "http://JxctXkZ1OTVnlwvguSCE9KtujacMkOLF@localhost:8888/api/v1/cluster/join?discovery-node=NodeB@10.0.0.2"

And the returned response would look like:

{
    "text": "Done",
    "type": "text"
}

Below are some other examples.

Get cluster status information

Request:

GET /api/v1/cluster/show

Curl:

curl "http://JxctXkZ1OTVnlwvguSCE9KtujacMkOLF@localhost:8888/api/v1/cluster/show"

Response:

{
   "type" : "table",
   "table" : [
      {
         "Running" : true,
         "Node" : "VerneMQ@127.0.0.1"
      }
   ]
}

Retrieve session information

Request:

GET /api/v1/session/show

Curl:

curl "http://JxctXkZ1OTVnlwvguSCE9KtujacMkOLF@localhost:8888/api/v1/session/show"

Response:

{
   "type" : "table",
   "table" : [
      {
         "user" : "client1",
         "peer_port" : 50402,
         "is_online" : true,
         "mountpoint" : "",
         "client_id" : "mosq/qJpvoqe1PA4lBN1e4E",
         "peer_host" : "127.0.0.1"
      },
      {
         "user" : "client2",
         "is_online" : true,
         "peer_port" : 50406,
         "peer_host" : "127.0.0.1",
         "client_id" : "mosq/tikkXdlM28PaznBv2T",
         "mountpoint" : ""
      }
   ]
}

List all installed listeners

Request:

GET /api/v1/listener/show

Curl:

curl "http://JxctXkZ1OTVnlwvguSCE9KtujacMkOLF@localhost:8888/api/v1/listener/show"

Response:

{
   "type" : "table",
   "table" : [
      {
         "max_conns" : 10000,
         "port" : "8888",
         "mountpoint" : "",
         "ip" : "127.0.0.1",
         "type" : "http",
         "status" : "running"
      },
      {
         "status" : "running",
         "max_conns" : 10000,
         "port" : "44053",
         "mountpoint" : "",
         "ip" : "0.0.0.0",
         "type" : "vmq"
      },
      {
         "max_conns" : 10000,
         "port" : "1883",
         "mountpoint" : "",
         "ip" : "127.0.0.1",
         "type" : "mqtt",
         "status" : "running"
      }
   ]
}

Retrieve plugin information

Request:

GET /api/v1/plugin/show

Curl:

curl "http://JxctXkZ1OTVnlwvguSCE9KtujacMkOLF@localhost:8888/api/v1/plugin/show"

Response:

    {
   "type" : "table",
   "table" : [
      {
         "Hook(s)" : "auth_on_register\n",
         "Plugin" : "vmq_passwd",
         "M:F/A" : "vmq_passwd:auth_on_register/5\n",
         "Type" : "application"
      },
      {
         "Type" : "application",
         "M:F/A" : "vmq_acl:auth_on_publish/6\nvmq_acl:auth_on_subscribe/3\n",
         "Plugin" : "vmq_acl",
         "Hook(s)" : "auth_on_publish\nauth_on_subscribe\n"
      }
   ]
}

Set configuration values

Request:

GET /api/v1/set?allow_publish_during_netsplit=on

Curl:

curl "http://JxctXkZ1OTVnlwvguSCE9KtujacMkOLF@localhost:8888/api/v1/set?allow_publish_during_netsplit=on"

Response:

[]

Disconnect a client

Request:

GET /api/v1/session/disconnect?client-id=myclient&--cleanup

Curl:

curl "http://JxctXkZ1OTVnlwvguSCE9KtujacMkOLF@localhost:8888/api/v1/session/disconnect?client-id=myclient&--cleanup"

Response:

[]