telegraf/plugins/inputs/httpjson/README.md

# HTTP JSON Input Plugin

The httpjson plugin collects data from HTTP URLs which respond with JSON.  It flattens the JSON and finds all numeric values, treating them as floats.

Deprecated (1.6): use the [http](../http) input.

### Configuration:

```toml
[[inputs.httpjson]]
  ## NOTE This plugin only reads numerical measurements, strings and booleans
  ## will be ignored.

  ## Name for the service being polled.  Will be appended to the name of the
  ## measurement e.g. "httpjson_webserver_stats".
  ##
  ## Deprecated (1.3.0): Use name_override, name_suffix, name_prefix instead.
  name = "webserver_stats"

  ## URL of each server in the service's cluster
  servers = [
    "http://localhost:9999/stats/",
    "http://localhost:9998/stats/",
  ]
  ## Set response_timeout (default 5 seconds)
  response_timeout = "5s"

  ## HTTP method to use: GET or POST (case-sensitive)
  method = "GET"

  ## Tags to extract from top-level of JSON server response.
  # tag_keys = [
  #   "my_tag_1",
  #   "my_tag_2"
  # ]

  ## Optional SSL Config
  # ssl_ca = "/etc/telegraf/ca.pem"
  # ssl_cert = "/etc/telegraf/cert.pem"
  # ssl_key = "/etc/telegraf/key.pem"
  ## Use SSL but skip chain & host verification
  # insecure_skip_verify = false

  ## HTTP Request Parameters (all values must be strings).  For "GET" requests, data
  ## will be included in the query.  For "POST" requests, data will be included
  ## in the request body as "x-www-form-urlencoded".
  # [inputs.httpjson.parameters]
  #   event_type = "cpu_spike"
  #   threshold = "0.75"

  ## HTTP Request Headers (all values must be strings).
  # [inputs.httpjson.headers]
  #   X-Auth-Token = "my-xauth-token"
  #   apiVersion = "v1"
```

### Measurements & Fields:

- httpjson
	- response_time (float): Response time in seconds

Additional fields are dependant on the response of the remote service being polled.

### Tags:

- All measurements have the following tags:
	- server: HTTP origin as defined in configuration as `servers`.

Any top level keys listed under `tag_keys` in the configuration are added as tags.  Top level keys are defined as keys in the root level of the object in a single object response, or in the root level of each object within an array of objects.


### Examples Output:

This plugin understands responses containing a single JSON object, or a JSON Array of Objects.

**Object Output:**

Given the following response body:
```json
{
    "a": 0.5,
    "b": {
        "c": "some text",
        "d": 0.1,
        "e": 5
    },
    "service": "service01"
}
```
The following metric is produced:

`httpjson,server=http://localhost:9999/stats/ b_d=0.1,a=0.5,b_e=5,response_time=0.001`

Note that only numerical values are extracted and the type is float.

If `tag_keys` is included in the configuration:

```toml
[[inputs.httpjson]]
  tag_keys = ["service"]
```

Then the `service` tag will also be added:

`httpjson,server=http://localhost:9999/stats/,service=service01 b_d=0.1,a=0.5,b_e=5,response_time=0.001`

**Array Output:**

If the service returns an array of objects, one metric is be created for each object:

```json
[
    {
        "service": "service01",
        "a": 0.5,
        "b": {
            "c": "some text",
            "d": 0.1,
            "e": 5
        }
    },
    {
        "service": "service02",
        "a": 0.6,
        "b": {
            "c": "some text",
            "d": 0.2,
            "e": 6
        }
    }
]
```

`httpjson,server=http://localhost:9999/stats/,service=service01 a=0.5,b_d=0.1,b_e=5,response_time=0.003`
`httpjson,server=http://localhost:9999/stats/,service=service02 a=0.6,b_d=0.2,b_e=6,response_time=0.003`