Decide on one (or more) formats for configuration files

[ocelotl]

This issue is related to #555

#466 introduced a configuration manager. Currently, it only reads from environment variables. For configuration files to be read, then it is necessary to define a few things first:

1. Where the configuration file would be located?
2. Do we want several formats to be supported or only one?
3. Which format or formats do we want to support?

Here are some formats for consideration:

1. JSON
2. YAML
3. TOML
4. Python (like Django does for its settings file)
5. INI

Please leave your thoughts about this in the comments below.

[mauriciovasquezbernal]

My 2cents: Supporting more than 1 format is a bad idea, users will be confused about with one is the correct one and what are the differences, we should also maintain them...

About the formats, I'd discard JSON because it doesn't support comment, I'd also discard INI because it only supports one level hierarchy tree. About the remaining ones I think yaml is the most used, so what would be my choice.

[codeboten]

Would love to see some progress on this discussion.... could we vote:

👍 JSON
❤️ YAML
🎉 TOML
🚀 Python (like Django does for its settings file)
😄 INI

[toumorokoshi]

I thing I'll call out that json and ini files I'd explicitly vote against.

ini files have no ability to do nested data structures, and as a result you end up writing a hacky way to express them.

json is hard to read and fairly error-prone (the fact that trailing commas are not allowed and error messages don't make that clear has made hand-editing json a trial, IME).

[codeboten]

worth nothing the collector uses yaml

[majorgreys]

Seems like the decision is between toml or yaml. Consistency across OpenTelemetry projects would be nice but I give more weight to the one more commonly used in each language. Given that I would vote for toml with it's ini style syntax.

[aabmass]

I voted YAML but I don't want to be the tie breaker lol

[Renz2018]

yaml is the most used

[ocelotl]

Does this mean that we can decide for YAML?

[lzchen]

+1 for YAH-mal

[ocelotl]

@lzchen @toumorokoshi

It seems like YAML is the chosen one. Can we close this issue?