Support custom configs

[lucasm-iRonin]

This simple change allows to provide additional DataDog configuration in the datadog folder in root of the application.

For testing on Heroku we can use this buildpack using https://github.com/DataDog/heroku-buildpack-datadog.git#custom-datadog URL.

[jyee]

Thanks for the PR. I think a few minor changes would be helpful:

• Move this block up to ~line 28 right after we're setting the conf.d location. This will help keep all the config placement in the same general area of the script.
• Update APP_DATADOG_DIR to /app/datadog/conf.d. We can then also add a /app/datadog/checks.d and duplicate the behavior so users can add custom checks.

[lucasm-iRonin]

@jyee thanks for review. I've added support for checks.d and updated README.

Could you check it once again, please?

[quinn]

thanks for implementing this!

[jyee]

Minor nit, but let's keep the extension as .yaml, not .yml

[jyee]

Sorry, I should have been a bit more clear. I was just asking for the change on line 30.

The checks.d dir contains python files that correspond to the yaml files and they'll also need to be added to the python path (logic around line 82). Let's keep this commit short and delete line 31 and this section. I can merge the config file part and we can work on adding logic bits in a separate PR.

Thanks again for all your work on this!

[lucasm-iRonin]

@jyee I've made changes according to your suggestions.

We can add checks.d in separate PR because it hasn't been tested as I didn't need to customize them.

[jyee]

Thanks again!