HTTP API Reference

Warning! This page documents an old version of Kapacitor, which is no longer actively developed. Kapacitor v1.3 is the most recent stable version of Kapacitor.

Kapacitor API Reference Documentation

General Information

Kapacitor provides an HTTP API on port 9092 by default. With the API you can control which tasks are executing, query status of tasks and manage recordings etc.

Each section below defines the available API endpoints and there inputs and outputs.

All requests are versioned and namespaced using the base path /kapacitor/v1/.

Response Codes

All requests can return these response codes:

HTTP Response Code Meaning
2xx The request was a success, content is dependent on the request.
4xx Invalid request, refer to error for what it wrong with the request. Repeating the request will continue to return the same error.
5xx The server was unable to process the request, refer to the error for a reason. Repeating the request may result in a success if the server issue has been resolved.

Errors

All requests can return JSON in the following format to provide more information about a failed request.

{
    "error" : "error message"
}

Query Parameters vs JSON body

To make using this API a consistent and easy experience we follow one simple rule for when extra information about a request is found in the query parameters of the URL or when they are part of the submitted JSON body.

Query parameters are used only for GET requests and all other requests expect parameters to be specified in the JSON body.

NOTE: The /kapacitor/v1/write endpoint is the one exception to this rule since Kapacitor is compatible with the InfluxDB /write endpoint.

When creating resources in Kapacitor the API server will return a link object with an href of the resource. Clients should not need to perform path manipulation in most cases and can use the links provided from previous calls.

Writing Data

Kapacitor can accept writes over HTTP using the line protocol. This endpoint is identical in nature to the InfluxDB write endpoint.

Query Parameter Purpose
db Database name for the writes.
rp Retention policy name for the writes.

NOTE: Kapacitor scopes all points by their database and retention policy. This means you MUST specify the rp for writes or Kapacitor will not know which retention policy to use.

Example

Write data to Kapacitor.

POST /kapacitor/v1/write?db=DB_NAME&rp=RP_NAME
cpu,host=example.com value=87.6

For compatibility with the equivalent InfluxDB write endpoint the /write endpoint is maintained as an alias to the /kapacitor/v1/write endpoint.

POST /write?db=DB_NAME&rp=RP_NAME
cpu,host=example.com value=87.6

Tasks

A task represents work for Kapacitor to perform. A task is defined by its id, type, TICKscript, and list of database retention policy pairs it is allowed to access.

Define Task

To define a task POST to the /kapacitor/v1/tasks/ endpoint. If a task already exists then use the PATCH method to modify any property of the task.

Define a task using a JSON object with the following options:

Property Purpose
id Unique identifier for the task. If empty a random ID will be chosen.
type The task type: stream or batch.
dbrps List of database retention policy pairs the task is allowed to access.
script The content of the script.
status One of enabled or disabled.

When using PATCH, if any option is missing it will be left unmodified.

Example

Create a new task with ID TASK_ID.

POST /kapacitor/v1/tasks/
{
    "id" : "TASK_ID",
    "type" : "stream",
    "dbrps": [{"db": "DATABASE_NAME", "rp" : "RP_NAME"}],
    "script": "stream\n    |from()\n        .measurement('cpu')\n"
}

Response with task id and link.

{
    "link" : {"rel": "self", "href": "/kapacitor/v1/tasks/TASK_ID"},
    "id" : "TASK_ID",
    "type" : "stream",
    "dbrps" : [{"db": "DATABASE_NAME", "rp" : "RP_NAME"}],
    "script" : "stream\n    |from()\n        .measurement('cpu')\n",
    "dot" : "digraph TASK_ID { ... }",
    "status" : "enabled",
    "executing" : true,
    "error" : "",
    "created": "2006-01-02T15:04:05Z07:00",
    "modified": "2006-01-02T15:04:05Z07:00",
    "stats" : {}
}

Modify only the dbrps of the task.

PATCH /kapacitor/v1/tasks/TASK_ID
{
    "dbrps": [{"db": "NEW_DATABASE_NAME", "rp" : "NEW_RP_NAME"}]
}

NOTE: Setting any DBRP will overwrite all stored DBRPs.

Enable an existing task.

PATCH /kapacitor/v1/tasks/TASK_ID
{
    "status" : "enabled",
}

Disable an existing task.

PATCH /kapacitor/v1/tasks/TASK_ID
{
    "status" : "disabled",
}

Define a new task that is enabled on creation.

POST /kapacitor/v1/tasks/TASK_ID
{
    "type" : "stream",
    "dbrps" : [{"db": "DATABASE_NAME", "rp" : "RP_NAME"}],
    "script" : "stream\n    |from()\n        .measurement('cpu')\n",
    "status" : "enabled"
}

Response with task id and link.

{
    "id" : "TASK_ID",
    "link" : {"rel": "self", "href": "/kapacitor/v1/tasks/TASK_ID"}
}

Response

Code Meaning
200 Task created, contains task information.
204 Task updated, no content
404 Task does not exist

Get Task

To get information about a task make a GET request to the /kapacitor/v1/tasks/TASK_ID endpoint.

Query Parameter Default Purpose
dot-view attributes One of labels or attributes. Labels is less readable but will correctly render with all the information contained in labels.
script-format formatted One of formatted or raw. Raw will return the script identical to how it was defined. Formatted will first format the script.

A task has these read only properties in addition to the properties listed above.

Property Description
dot GraphViz DOT) syntax formatted representation of the task DAG.
executing Whether the task is currently executing.
error Any error encountered when executing the task.
stats Map of statistics about a task.
created Date the task was first created
modified Date the task was last modified
last-enabled Date the task was last set to status enabled

Example

Get information about a task using defaults.

GET /kapacitor/v1/tasks/TASK_ID
{
    "link" : {"rel": "self", "href": "/kapacitor/v1/tasks/TASK_ID"},
    "id" : "TASK_ID",
    "type" : "stream",
    "dbrps" : [{"db": "DATABASE_NAME", "rp" : "RP_NAME"}],
    "script" : "stream\n    |from()\n        .measurement('cpu')\n",
    "dot" : "digraph TASK_ID { ... }",
    "status" : "enabled",
    "executing" : true,
    "error" : "",
    "created": "2006-01-02T15:04:05Z07:00",
    "modified": "2006-01-02T15:04:05Z07:00",
    "last-enabled": "2006-01-03T15:04:05Z07:00",
    "stats" : {}
}

Get information about a task using only labels in the DOT content and skip the format step.

GET /kapacitor/v1/tasks/TASK_ID?dot-view=labels&script-format=raw
{
    "link" : {"rel": "self", "href": "/kapacitor/v1/tasks/TASK_ID"},
    "id" : "TASK_ID",
    "type" : "stream",
    "dbrps" : [{"db": "DATABASE_NAME", "rp" : "RP_NAME"}],
    "script" : "stream|from().measurement('cpu')",
    "dot" : "digraph TASK_ID { ... }",
    "status" : "enabled",
    "executing" : true,
    "error" : "",
    "created": "2006-01-02T15:04:05Z07:00",
    "modified": "2006-01-02T15:04:05Z07:00",
    "last-enabled": "2006-01-03T15:04:05Z07:00",
    "stats" : {}
}

Response

Code Meaning
200 Success
404 Task does not exist

Delete Task

To delete a task make a DELETE request to the /kapacitor/v1/tasks/TASK_ID endpoint.

DELETE /kapacitor/v1/tasks/TASK_ID

Response

Code Meaning
204 Success

NOTE: Deleting a non-existent task is not an error and will return a 204 success.

List Tasks

To get information about several tasks make a GET request to the /kapacitor/v1/tasks endpoint.

Query Parameter Default Purpose
pattern Filter results based on the pattern. Uses standard shell glob matching, see this for more details.
fields List of fields to return. If empty returns all fields. Fields id and link are always returned.
dot-view attributes One of labels or attributes. Labels is less readable but will correctly render with all the information contained in labels.
script-format formatted One of formatted or raw. Raw will return the script identical to how it was defined. Formatted will first format the script.
offset 0 Offset count for paginating through tasks.
limit 100 Maximum number of tasks to return.

Example

Get all tasks.

GET /kapacitor/v1/tasks
{
    "tasks" : [
        {
            "link" : {"rel":"self", "href":"/kapacitor/v1/tasks/TASK_ID"},
            "id" : "TASK_ID",
            "type" : "stream",
            "dbrps" : [{"db": "DATABASE_NAME", "rp" : "RP_NAME"}],
            "script" : "stream|from().measurement('cpu')",
            "dot" : "digraph TASK_ID { ... }",
            "status" : "enabled",
            "executing" : true,
            "error" : "",
            "stats" : {}
        },
        {
            "link" : {"rel":"self", "href":"/kapacitor/v1/tasks/ANOTHER_TASK_ID"},
            "id" : "ANOTHER_TASK_ID",
            "type" : "stream",
            "dbrps" : [{"db": "DATABASE_NAME", "rp" : "RP_NAME"}],
            "script" : "stream|from().measurement('cpu')",
            "dot" : "digraph ANOTHER_TASK_ID{ ... }",
            "status" : "disabled",
            "executing" : true,
            "error" : "",
            "stats" : {}
        }
    ]
}

Optionally specify a glob pattern to list only matching tasks.

GET /kapacitor/v1/task?pattern=TASK*
{
    "tasks" : [
        {
            "link" : {"rel":"self", "href":"/kapacitor/v1/tasks/TASK_ID"},
            "id" : "TASK_ID",
            "type" : "stream",
            "dbrps" : [{"db": "DATABASE_NAME", "rp" : "RP_NAME"}],
            "script" : "stream|from().measurement('cpu')",
            "dot" : "digraph TASK_ID { ... }",
            "status" : "enabled:,
            "executing" : true,
            "error" : "",
            "stats" : {}
        }
    ]
}

Get all tasks, but only the status, executing and error fields.

GET /kapacitor/v1/tasks?fields=status&fields=executing&fields=error
{
    "tasks" : [
        {
            "link" : {"rel":"self", "href":"/kapacitor/v1/tasks/TASK_ID"},
            "id" : "TASK_ID",
            "status" : "enabled",
            "executing" : true,
            "error" : "",
        },
        {
            "link" : {"rel":"self", "href":"/kapacitor/v1/tasks/ANOTHER_TASK_ID"},
            "id" : "ANOTHER_TASK_ID",
            "status" : "disabled",
            "executing" : true,
            "error" : "",
        }
    ]
}

Response

Code Meaning
200 Success

NOTE: If the pattern does not match any tasks an empty list will be returned, with a 200 success.

Custom Task HTTP Endpoints

In TICKscript it is possible to expose a cache of recent data via the HTTPOut node. The data is available at the path /kapacitor/v1/tasks/TASK_ID/ENDPOINT_NAME.

Example

For the TICKscript:

stream
    |from()
        .measurement('cpu')
    |window()
        .period(60s)
        .every(60s)
    |httpOut('mycustom_endpoint')
GET /kapacitor/v1/tasks/TASK_ID/mycustom_endpoint
{
    "series": [
        {
            "name": "cpu",
            "columns": [
                "time",
                "value"
            ],
            "values": [
                [
                    "2015-01-29T21:55:43.702900257Z",
                    55
                ],
                [
                    "2015-01-29T21:56:43.702900257Z",
                    42
                ],
            ]
        }
    ]
}

The output is the same as a query for data to InfluxDB.

Recordings

Kapacitor can save recordings of data and replay them against a specified task.

Start Recording

There are three methods for recording data with Kapacitor: To create a recording make a POST request to the /kapacitor/v1/recordings/METHOD endpoint.

Method Description
stream Record the incoming stream of data.
batch Record the results of the queries in a batch task.
query Record the result of an explicit query.

The request returns once the recording is started and does not wait for it to finish. A recording ID is returned to later identify the recording.

Stream
Parameter Purpose
id Unique identifier for the recording. If empty a random one will be chosen.
task ID of a task, used to only record data for the DBRPs of the task.
stop Record stream data until stop date.
Batch
Parameter Purpose
id Unique identifier for the recording. If empty a random one will be chosen.
task ID of a task, records the results of the queries defined in the task.
start Earliest date for which data will be recorded. RFC3339Nano formatted.
stop Latest date for which data will be recorded. If not specified uses the current time. RFC3339Nano formatted data.
cluster Name of a configured InfluxDB cluster. If empty uses the default cluster.
Query
Parameter Purpose
id Unique identifier for the recording. If empty a random one will be chosen.
type Type of recording, stream or batch.
query Query to execute.
cluster Name of a configured InfluxDB cluster. If empty uses the default cluster.

NOTE: A recording itself is typed as either a stream or batch recording and can only be replayed to a task of a corresponding type. Therefore when you record the result of a raw query you must specify the type recording you wish to create.

Example

Create a recording using the stream method

POST /kapacitor/v1/recordings/stream
{
    "task" : "TASK_ID",
    "stop" : "2006-01-02T15:04:05Z07:00"
}

Create a recording using the batch method specifying a start time.

POST /kapacitor/v1/recordings/batch
{
    "task" : "TASK_ID",
    "start" : "2006-01-02T15:04:05Z07:00"
}

Create a recording using the query method specifying a stream type.

POST /kapacitor/v1/recordings/query
{
    "query" : "SELECT mean(usage_idle) FROM cpu WHERE time > now() - 1h GROUP BY time(10m)",
    "type" : "stream"
}

Create a recording using the query method specifying a batch type.

POST /kapacitor/v1/recording/query
{
    "query" : "SELECT mean(usage_idle) FROM cpu WHERE time > now() - 1h GROUP BY time(10m)",
    "type" : "batch"
}

Create a recording with a custom ID.

POST /kapacitor/v1/recording/query
{
    "id" : "MY_RECORDING_ID",
    "query" : "SELECT mean(usage_idle) FROM cpu WHERE time > now() - 1h GROUP BY time(10m)",
    "type" : "batch"
}

Response

All recordings are assigned an ID which is returned in this format with a link.

{
    "link" : {"rel": "self", "href": "/kapacitor/v1/recordings/e24db07d-1646-4bb3-a445-828f5049bea0"},
    "id" : "e24db07d-1646-4bb3-a445-828f5049bea0",
    "type" : "stream",
    "size" : 0,
    "date" : "2006-01-02T15:04:05Z07:00",
    "error" : "",
    "status" : "running",
    "progress" : 0
}
Code Meaning
201 Success, the recording has started.

Wait for Recording

In order to determine when a recording has finished you must make a GET request to the returned link typically something like /kapacitor/v1/recordings/RECORDING_ID.

A recording has these read only properties.

Property Description
size Size of the recording on disk in bytes.
date Date the recording finished.
error Any error encountered when creating the recording.
status One of recording or finished.
progress Number between 0 and 1 indicating the approximate progress of the recording.

Example

GET /kapacitor/v1/recordings/e24db07d-1646-4bb3-a445-828f5049bea0
{
    "link" : {"rel": "self", "href": "/kapacitor/v1/recordings/e24db07d-1646-4bb3-a445-828f5049bea0"},
    "id" : "e24db07d-1646-4bb3-a445-828f5049bea0",
    "type" : "stream",
    "size" : 1980353,
    "date" : "2006-01-02T15:04:05Z07:00",
    "error" : "",
    "status" : "running",
    "progress" : 0.75
}

Once the recording is complete.

GET /kapacitor/v1/recordings/e24db07d-1646-4bb3-a445-828f5049bea0
{
    "link" : {"rel": "self", "href": "/kapacitor/v1/recordings/e24db07d-1646-4bb3-a445-828f5049bea0"},
    "id" : "e24db07d-1646-4bb3-a445-828f5049bea0",
    "type" : "stream",
    "size" : 1980353,
    "date" : "2006-01-02T15:04:05Z07:00",
    "error" : "",
    "status" : "finished",
    "progress" : 1
}

Or if the recording fails.

GET /kapacitor/v1/recordings/e24db07d-1646-4bb3-a445-828f5049bea0
{
    "link" : {"rel": "self", "href": "/kapacitor/v1/recordings/e24db07d-1646-4bb3-a445-828f5049bea0"},
    "id" : "e24db07d-1646-4bb3-a445-828f5049bea0",
    "type" : "stream",
    "size" : 1980353,
    "date" : "2006-01-02T15:04:05Z07:00",
    "error" : "error message explaining failure",
    "status" : "failed",
    "progress" : 1
}

Response

Code Meaning
200 Success, the recording is no longer running.
202 Success, the recording exists but is not finished.
404 No such recording exists.

Delete Recording

To delete a recording make a DELETE request to the /kapacitor/v1/recordings/RECORDING_ID endpoint.

DELETE /kapacitor/v1/recordings/RECORDING_ID

Response

Code Meaning
204 Success

NOTE: Deleting a non-existent recording is not an error and will return a 204 success.

List Recordings

To list all recordings make a GET request to the /kapacitor/v1/recordings endpoint. Recordings are sorted by date.

Query Parameter Default Purpose
pattern Filter results based on the pattern. Uses standard shell glob matching, see this for more details.
fields List of fields to return. If empty returns all fields. Fields id and link are always returned.
offset 0 Offset count for paginating through tasks.
limit 100 Maximum number of tasks to return.

Example

GET /kapacitor/v1/recordings
{
    "recordings" : [
        {
            "link" : {"rel": "self", "href": "/kapacitor/v1/recordings/e24db07d-1646-4bb3-a445-828f5049bea0"},
            "id" : "e24db07d-1646-4bb3-a445-828f5049bea0",
            "type" : "stream",
            "size" : 1980353,
            "date" : "2006-01-02T15:04:05Z07:00",
            "error" : "",
            "status" : "finished",
            "progress" : 1
        },
        {
            "link" : {"rel": "self", "href": "/kapacitor/v1/recordings/8a4c06c6-30fb-42f4-ac4a-808aa31278f6"},
            "id" : "8a4c06c6-30fb-42f4-ac4a-808aa31278f6",
            "type" : "batch",
            "size" : 216819562,
            "date" : "2006-01-02T15:04:05Z07:00",
            "error" : "",
            "status" : "finished",
            "progress" : 1
        }
    ]
}

Response

Code Meaning
200 Success

Replays

Replaying a recording

To replay a recording make a POST request to /kapacitor/v1/replays/

Parameter Default Purpose
id random Unique identifier for the replay. If empty a random ID is chosen.
task ID of task.
recording ID of recording.
recording-time false If true, use the times in the recording, otherwise adjust times relative to the current time.
clock fast One of fast or real. If real wait for real time to pass corresponding with the time in the recordings. If fast replay data without delay. For example, if clock is real then a stream recording of duration 5m will take 5m to replay.

Example

Replay a recording using default parameters.

POST /kapacitor/v1/replays/
{
    "task" : "TASK_ID",
    "recording" : "RECORDING_ID"
}

Replay a recording in real-time mode and preserve recording times.

POST /kapacitor/v1/replays/
{
    "task" : "TASK_ID",
    "recording" : "RECORDING_ID",
    "clock" : "real",
    "recording-time" : true,
}

Replay a recording using a custom ID.

POST /kapacitor/v1/replays/
{
    "id" : "MY_REPLAY_ID",
    "task" : "TASK_ID",
    "recording" : "RECORDING_ID"
}

Response

The request returns once the replay is started and provides a replay ID and link.

{
    "link" : {"rel": "self", "href": "/kapacitor/v1/replays/ad95677b-096b-40c8-82a8-912706f41d4c"},
    "id" : "ad95677b-096b-40c8-82a8-912706f41d4c",
    "task" : "TASK_ID",
    "recording" : "RECORDING_ID",
    "clock" : "fast",
    "recording-time" : false,
    "status" : "running",
    "progress" : 0,
    "error" : ""
}
Code Meaning
201 Success, replay has started.

Waiting for a Replay

Like recordings you make a GET request to the /kapacitor/v1/replays/REPLAY_ID endpoint to get the status of the replay.

A replay has these read only properties in addition to the properties listed above.

Property Description
status One of replaying or finished.
progress Number between 0 and 1 indicating the approximate progress of the replay.
error Any error that occured while perfoming the replay

Example

Get the status of a replay.

GET /kapacitor/v1/replays/ad95677b-096b-40c8-82a8-912706f41d4c
{
    "link" : {"rel": "self", "href": "/kapacitor/v1/replays/ad95677b-096b-40c8-82a8-912706f41d4c"},
    "id" : "ad95677b-096b-40c8-82a8-912706f41d4c",
    "task" : "TASK_ID",
    "recording" : "RECORDING_ID",
    "clock" : "fast",
    "recording-time" : false,
    "status" : "running",
    "progress" : 0.57,
    "error" : ""
}

Once the replay is complete.

GET /kapacitor/v1/replays/ad95677b-096b-40c8-82a8-912706f41d4c
{
    "link" : {"rel": "self", "href": "/kapacitor/v1/replays/ad95677b-096b-40c8-82a8-912706f41d4c"},
    "id" : "ad95677b-096b-40c8-82a8-912706f41d4c",
    "task" : "TASK_ID",
    "recording" : "RECORDING_ID",
    "clock" : "fast",
    "recording-time" : false,
    "status" : "finished",
    "progress" : 1,
    "error" : ""
}

Or if the replay fails.

GET /kapacitor/v1/replays/ad95677b-096b-40c8-82a8-912706f41d4c
{
    "link" : {"rel": "self", "href": "/kapacitor/v1/replays/ad95677b-096b-40c8-82a8-912706f41d4c"},
    "id" : "ad95677b-096b-40c8-82a8-912706f41d4c",
    "task" : "TASK_ID",
    "recording" : "RECORDING_ID",
    "clock" : "fast",
    "recording-time" : false,
    "status" : "failed",
    "progress" : 1,
    "error" : "error message explaining failure"
}

Response

Code Meaning
200 Success, replay is no longer running.
202 Success, the replay exists but is not finished.
404 No such replay exists.

Delete Replay

To delete a replay make a DELETE request to the /kapacitor/v1/replays/REPLAY_ID endpoint.

DELETE /kapacitor/v1/replays/REPLAY_ID

Response

Code Meaning
204 Success

NOTE: Deleting a non-existent replay is not an error and will return a 204 success.

List Replays

You can list replays for a given recording by making a GET request to /kapacitor/v1/replays.

Query Parameter Default Purpose
pattern Filter results based on the pattern. Uses standard shell glob matching, see this for more details.
fields List of fields to return. If empty returns all fields. Fields id and link are always returned.
offset 0 Offset count for paginating through tasks.
limit 100 Maximum number of tasks to return.

Example

GET /kapacitor/v1/replays
{
    "replays" [
        {
            "link" : {"rel": "self", "href": "/kapacitor/v1/replays/ad95677b-096b-40c8-82a8-912706f41d4c"},
            "id" : "ad95677b-096b-40c8-82a8-912706f41d4c",
            "task" : "TASK_ID",
            "recording" : "RECORDING_ID",
            "clock" : "fast",
            "recording-time" : false,
            "status" : "finished",
            "progress" : 1,
            "error" : ""
        },
        {
            "link" : {"rel": "self", "href": "/kapacitor/v1/replays/be33f0a1-0272-4019-8662-c730706dac7d"},
            "id" : "be33f0a1-0272-4019-8662-c730706dac7d",
            "task" : "TASK_ID",
            "recording" : "RECORDING_ID",
            "clock" : "fast",
            "recording-time" : false,
            "status" : "finished",
            "progress" : 1,
            "error" : ""
        }
    ]
}

Miscellaneous

Ping

You can ‘ping’ the Kapacitor server to validate you have a successful connection. A ping request does nothing but respond with a 204.

NOTE: The Kapacitor server version is returned in the X-Kapacitor-Version HTTP header on all requests. Ping is a useful request if you simply need the verify the version of server you are talking to.

Example

GET /kapacitor/v1/ping

Response

Code Meaning
204 Success

Debug Vars

Kapacitor also exposes several statistics and information about its runtime. These can be accessed at the /kapacitor/v1/debug/vars endpoint.

Example

GET /kapacitor/v1/debug/vars

Debug Pprof

Kapacitor also the standard Go net/http/pprof endpoints.

GET /kapacitor/v1/debug/pprof/...

NOTE: Not all of these endpoints return JSON content.

Routes

Displays available routes for the API

GET /kapacitor/v1/:routes