Use mapping syntax for environment variables in docker-compose example

[isidroas]

• Convert environment entries from list syntax to key/value mapping syntax
• Keep existing variable values and behavior unchanged

[dgtlmoon]

is it the whole YML that needs this change?

[isidroas]

It is not required, but I would be fine with converting the rest as well so the whole compose file keeps a consistent style

[dgtlmoon]

It is not required, but I would be fine with converting the rest as well so the whole compose file keeps a consistent style

more consistent more better :) yes please

[isidroas]

Done. The disadvantage is that it needs quoting for some values

[AmirF194]

The motivation makes sense, mapping syntax does read better than the list form, and the genuinely tricky part is handled well: every value that YAML would coerce is quoted correctly. I checked each one and they matter. Unquoted ALLOW_FILE_URI: False would fold to the string "false" (lowercase, wrong), and HIDE_REFERER/DISABLE_VERSION_CHECK: true and LISTEN_HOST: :: are all coercion or parse hazards, so quoting them as 'False', 'true', '::' preserves the intended strings. That is the part people usually get wrong. The embedded-colon values (ws://...:3000, http://...:4444/wd/hub, etc.) are safe unquoted because each colon is followed by a non-space, and bare integers are fine since compose stringifies them.

One blocking issue: outside the selenium block, most of the converted lines keep the leading - , so they become - KEY: value rather than KEY: value. That is a list item whose value is a map, not mapping syntax, and docker compose rejects it. I reproduced it on compose v5.0.2:

services.changedetection.environment.[0]: unexpected type map[string]interface{}

It looks like a mechanical = to : substitution that kept the list markers, whereas the selenium block was hand-edited correctly with the dashes removed. Since this file is a copy-paste-and-uncomment example, an uncommented line that fails validation is a real problem, and right now the file is internally inconsistent (selenium correct, the rest not). Dropping the - on the converted lines in the changedetection and sockpuppet-browser blocks would make them match selenium and the PR title.

Two optional notes: the description says behavior is unchanged, but two values actually do change, both arguably for the better. NO_PROXY in list form kept its literal quote characters, and mapping form strips them; CHROME_OPTIONS moved from | (newline-separated) to > (space-separated), which is what Chrome flags actually want. Worth a line in the description. And LISTEN_HOST: '::' is quoted while the alternate LISTEN_HOST: 0.0.0.0 is not, both correct, just slightly inconsistent to read.

[dgtlmoon]

Thanks for the PR! Unfortunately this conversion isn't quite right and I don't think we should merge it as-is.

Most of the file ends up as invalid syntax. The change produces a hybrid like:

environment:
  - PORT: 5000
  - LOGGER_LEVEL: TRACE

That's neither valid form. Docker Compose accepts either:

• List syntax: - PORT=5000 (dash, =, string), or
• Mapping syntax: PORT: 5000 (no dash, :)

- PORT: 5000 is a list of single-key maps, which Compose does not accept for environment:, so uncommenting these would error out — the "behavior unchanged" goal isn't actually met.

It's also inconsistent — only the selenium block at the bottom was converted correctly (dashes removed):

environment:
  VNC_NO_PASSWORD: 1
  SCREEN_WIDTH: 1920

...while the rest kept the - prefix.

Minor: mapping syntax also changes YAML typing. Some values were quoted (HIDE_REFERER: 'true'), others left bare (FETCH_WORKERS: 10) — this is exactly the quoting subtlety that makes the plain KEY=value list form (always a string) the safer default for a copy-paste example file.

If you'd like to pursue this, could you (a) drop the - dashes everywhere so it's true mapping syntax, and (b) quote scalar values consistently? Otherwise the existing list syntax works fine and I'm inclined to keep it. Thanks again!