YAML format discussion

[frauzufall]

At the hackathon we were discussing if YAML is the format we want to go with.

@uschmidt83 had issues installing the python PyYAML. Also, the autogenerated YAML file looks weird.

There might be better options and if you are interested in discussing this, do it here :)

[emilmelnikov]

One can preserve key order if Python dicts are ordered and sort_keys=False:

import yaml
print(yaml.dump({"c": 3, "z": 2, "a": 1}, default_flow_style=False, sort_keys=False))

c: 3
z: 2
a: 1

import yaml
print(yaml.dump({"c": 3, "z": 2, "a": 1}, default_flow_style=False, sort_keys=True))

a: 1
c: 3
z: 2

PyYAML version is 5.2.

See yaml/pyyaml#110 (comment).

[constantinpape]

What alternatives do you have in mind?

I think we decided on yaml because it's pretty common in the python space and more readable than xml (and xml parsing in python is a bit unconvenient). From my experience pyyaml is fairly easy to install, but I almost always do it via conda.

[MartinHjelmare]

Using yaml in the config doesn't necessarily mean we have to use PyYAML. There's also ruamel.yaml.

https://pypi.org/project/ruamel.yaml/

https://yaml.readthedocs.io/en/latest/pyyaml.html#differences-with-pyyaml

[m-novikov]

This snippet show how to control list representation in pyyaml

import yaml

class FlowStyleList(list):
    pass

def flow_representer(dumper, data):
    return dumper.represent_sequence("tag:yaml.org,2002:seq", data, flow_style=True)

yaml.add_representer(FlowStyleList, flow_representer)
print(yaml.dump({
    "a": FlowStyleList(["a", "b", "c"]),
    "b": ["a", "b", "c"],
}))

Results in following yaml:

a: [a, b, c]
b:
  - a
  - b
  - c

[FynnBe]

I suppose it's YAML for now, feel free to reopen and restart the discussion