Ability to retrieve string value via httpjson

[amertner]

Feature Request

I'd like to retrieve a string value in an http request, for example using inputs.http-response or inputs.httpjson. However, http-response discards any text returned, and httpjson ignores values that are not numbers.

Proposal:

I'd like to be able to process a json response a la this one, to create a field called ip:
{"ip":"81.171.xx.xx"}

Alternatively, I'd like to just have the entire http reply made available as a field so I can parse it.

Current behavior:

The json parser ignores fields that are not numbers.

Desired behavior:

The json parser should include fields that contain string values.

Use case: [Why is this important (helps with prioritizing requests)]

I would like to monitor my public IP addresses, using a service such as

https://api.ipify.org?format=json

(for json) or just this to get a straight string:

https://api.ipify.org

I think it could be useful for a wide range of other purposes, where people have an HTTP-based service that returns useful data that is not just a number.

[danielnelson]

It would be great to have support for more advanced JSON parsing, I've been thinking about JSON Pointer or JSONPath.

We could also add a json_field_keys parser option that would behave like tag_keys.

In the meantime, you would need to use the exec plugin.

[danielnelson]

#1363

[Dripoul]

Hello guys,

Is that possible to know if this issue will be resolved on the next weeks/months ?
I'm very interested by retrieving Strings values by "httpjson" plugin in a monitoring project.

Thank you !

[danielnelson]

@Dripoul I'm not aware of any direct work on this, if you are interested in working on this let me know. Don't forget you can get strings as tags today with tag_keys.

[marianob85]

I've made another input for json and xml with full tree support also with strings as value. It's still under develop but in working state. The custom tags are not implemented yet.
https://github.com/marianob85/telegraf/tree/WebApi

[danielnelson]

We are planning to merge #3546 soon, it is a HTTP input that can handle any of the input data formats and will eventually deprecate httpjson. We still need help on the next generation JSON parser #1363 and a XML parser #1758.

[danielnelson]

In 1.8.0, this can be done with the string_keys option.

[jbrischle]

@danielnelson could you please add this to the readme? Thanks.

[danielnelson]

My previous comment has the incorrect option name, it should be json_strings_fields. The documentation for the JSON parser(data_format = "json") is here:

https://github.com/influxdata/telegraf/blob/master/docs/DATA_FORMATS_INPUT.md#json

Keep in mind that this must be used with an input that supports the data_format option, in this case you will want to use the http input.