telegraf/plugins/parsers/json/README.md

# JSON

The JSON data format parses a [JSON][json] object or an array of objects into
metric fields.

**NOTE:** All JSON numbers are converted to float fields.  JSON String are
ignored unless specified in the `tag_key` or `json_string_fields` options.

### Configuration

```toml
[[inputs.file]]
  files = ["example"]

  ## Data format to consume.
  ## Each data format has its own unique set of configuration options, read
  ## more about them here:
  ## https://github.com/influxdata/telegraf/blob/master/docs/DATA_FORMATS_INPUT.md
  data_format = "json"

  ## Query is a GJSON path that specifies a specific chunk of JSON to be
  ## parsed, if not specified the whole document will be parsed.
  ##
  ## GJSON query paths are described here:
  ##   https://github.com/tidwall/gjson#path-syntax
  json_query = ""

  ## Tag keys is an array of keys that should be added as tags.
  tag_keys = [
    "my_tag_1",
    "my_tag_2"
  ]

  ## String fields is an array of keys that should be added as string fields.
  json_string_fields = []

  ## Name key is the key to use as the measurement name.
  json_name_key = ""

  ## Time key is the key containing the time that should be used to create the
  ## metric.
  json_time_key = ""

  ## Time format is the time layout that should be used to interprete the json_time_key.
  ## The time must be `unix`, `unix_ms`, `unix_us`, `unix_ns`, or a time in the
  ## "reference time".  To define a different format, arrange the values from
  ## the "reference time" in the example to match the format you will be
  ## using.  For more information on the "reference time", visit
  ## https://golang.org/pkg/time/#Time.Format
  ##   ex: json_time_format = "Mon Jan 2 15:04:05 -0700 MST 2006"
  ##       json_time_format = "2006-01-02T15:04:05Z07:00"
  ##       json_time_format = "01/02/2006 15:04:05"
  ##       json_time_format = "unix"
  ##       json_time_format = "unix_ms"
  json_time_format = ""

  ## Timezone allows you to provide an override for timestamps that
  ## don't already include an offset
  ## e.g. 04/06/2016 12:41:45
  ##
  ## Default: "" which renders UTC
  ## Options are as follows:
  ##   1. Local               -- interpret based on machine localtime
  ##   2. "America/New_York"  -- Unix TZ values like those found in https://en.wikipedia.org/wiki/List_of_tz_database_time_zones
  ##   3. UTC                 -- or blank/unspecified, will return timestamp in UTC
  json_timezone = ""
```

#### json_query

The `json_query` is a [GJSON][gjson] path that can be used to limit the
portion of the overall JSON document that should be parsed.  The result of the
query should contain a JSON object or an array of objects.

Consult the GJSON [path syntax][gjson syntax] for details and examples.

#### json_time_key, json_time_format, json_timezone

By default the current time will be used for all created metrics, to set the
time using the JSON document you can use the `json_time_key` and
`json_time_format` options together to set the time to a value in the parsed
document.

The `json_time_key` option specifies the key containing the time value and
`json_time_format` must be set to `unix`, `unix_ms`, `unix_us`, `unix_ns`, or
the Go "reference time" which is defined to be the specific time:
`Mon Jan 2 15:04:05 MST 2006`.

Consult the Go [time][time parse] package for details and additional examples
on how to set the time format.

When parsing times that don't include a timezone specifier, times are assumed
to be UTC. To default to another timezone, or to local time, specify the
`json_timezone` option.  This option should be set to a
[Unix TZ value](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones),
such as `America/New_York`, to `Local` to utilize the system timezone, or to `UTC`.

### Examples

#### Basic Parsing
Config:
```toml
[[inputs.file]]
  files = ["example"]
  name_override = "myjsonmetric"
  data_format = "json"
```

Input:
```json
{
    "a": 5,
    "b": {
        "c": 6
    },
    "ignored": "I'm a string"
}
```

Output:
```
myjsonmetric a=5,b_c=6
```

#### Name, Tags, and String Fields

Config:
```toml
[[inputs.file]]
  files = ["example"]
  json_name_key = "name"
  tag_keys = ["my_tag_1"]
  json_string_fields = ["b_my_field"]
  data_format = "json"
```

Input:
```json
{
    "a": 5,
    "b": {
        "c": 6,
        "my_field": "description"
    },
    "my_tag_1": "foo",
    "name": "my_json"
}
```

Output:
```
my_json,my_tag_1=foo a=5,b_c=6,b_my_field="description"
```

#### Arrays

If the JSON data is an array, then each object within the array is parsed with
the configured settings.

Config:
```toml
[[inputs.file]]
  files = ["example"]
  data_format = "json"
  json_time_key = "b_time"
  json_time_format = "02 Jan 06 15:04 MST"
```

Input:
```json
[
    {
        "a": 5,
        "b": {
            "c": 6,
            "time":"04 Jan 06 15:04 MST"
        }
    },
    {
        "a": 7,
        "b": {
            "c": 8,
            "time":"11 Jan 07 15:04 MST"
        }
    }
]
```

Output:
```
file a=5,b_c=6 1136387040000000000
file a=7,b_c=8 1168527840000000000
```

#### Query

The `json_query` option can be used to parse a subset of the document.

Config:
```toml
[[inputs.file]]
  files = ["example"]
  data_format = "json"
  tag_keys = ["first"]
  json_string_fields = ["last"]
  json_query = "obj.friends"
```

Input:
```json
{
    "obj": {
        "name": {"first": "Tom", "last": "Anderson"},
        "age":37,
        "children": ["Sara","Alex","Jack"],
        "fav.movie": "Deer Hunter",
        "friends": [
            {"first": "Dale", "last": "Murphy", "age": 44},
            {"first": "Roger", "last": "Craig", "age": 68},
            {"first": "Jane", "last": "Murphy", "age": 47}
        ]
    }
}
```

Output:
```
file,first=Dale last="Murphy",age=44
file,first=Roger last="Craig",age=68
file,first=Jane last="Murphy",age=47
```

[gjson]:        https://github.com/tidwall/gjson
[gjson syntax]: https://github.com/tidwall/gjson#path-syntax
[json]:         https://www.json.org/
[time parse]:   https://golang.org/pkg/time/#Parse