Within the Docker API/engine, networks have unique IDs, and the
name is a friendly label/alias, which notably does NOT have any
guarantees around uniqueness (see moby/moby#18864 [^1]).
During day-to-day interactive/CLI Compose usage, this is rarely
an issue, as Compose itself isn't creating networks concurrently
across goroutines. However, if multiple Compose instances are
executed simultaneously (e.g. as part of a test suite that runs
in parallel), this can easily occur.
When it does happen, it's very confusing for users and resolving
it via the `docker` CLI is not straightforward either [^2].
There's two primary changes here:
* Pass `CheckDuplicates: true` to the Docker API when creating
networks to reduce the likelihood of Compose creating duplicates
in the first place
* On `down`, list networks using a name filter and then remove
them all by ID, as the Docker API will return an error if the
name alias is used and maps to more than one network
Hopefully, this provides a better UX, since the issue should be
less likely to occur, and if it does, it can now be resolved via
standard Compose workflow commands.
[^1]: https://github.com/moby/moby/issues/18864
[^2]: https://stackoverflow.com/questions/63776518/error-2-matches-found-based-on-name-network-nameofservice-default-is-ambiguo
Signed-off-by: Milas Bowman <milas.bowman@docker.com>
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