feat(multiple-dist-tags): add proposal for multiple dist-tags

accepted/0000-multiple-dist-tags.md

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+# Allow for multiple dist-tags in a single command
+
+## Summary
+
+When publishing, and when adding and removing dist-tags, the user should
+be able to specify multiple dist-tags
+
+## Motivation
+
+Allowing for multple tags to be set on a given version at once will
+streamline many users' workflows.  Currently they must add tags
+one-at-a-time to any new versions they published, and can only set one
+of those tags during the publish action itself.
+
+## Detailed Explanation
+
+Both `npm publish` and `npm dist-tag` will be affected.
+
+The `--tag` parameter for `npm-publish` will parse as an optionally
+comma-separated list of tags.  Since a comma is not a valid character
+currently in tags, this does not present a breaking change.
+
+The `add` and `rm` commands would parse their `<tag>` parameter as a
+comma-separated list of tags.
+
+## Rationale and Alternatives
+
+One approach is to have postinstall scripts that handle this. This is
+what some maintainers are doing now and it is not very practical because
+it is simply working around the limitations of the existing system only
+allowing one tag at a time.  Adding lifecycle methods is less preferable
+to being able to specify the tags all at once when you would be changing
+them in the first place.
+
+Another approach is to add a config option of tags to add automatically
+to a package when it is published.  This is not a good choice because
+those defaults may only work for the latest versions of a package, and
+not changes to older semver-major versions. Overriding that kind of a
+setting would be quite cumbersome if implemented.
+
+## Implementation
+
+```sh
+$ npm publish --tag latest,next,latest-7
+```
+This would publish your package, and add the dist-tags of `latest`,
+`next`, and `latest-7` to the version being published
+
+```sh
+$ npm dist-tag add npm@6.14.11 latest-6,lts
+```
+
+This would set two dist-tags for the `npm` package: `latest-6` and
+`lts`. They would both point to the version `6.14.11`
+
+```sh
+$ npm dist-tag rm npm next-2,next-3,next-4
+```
+
+This would remove the `next-2`, `next-3`, and `next-4` tags from the
+`npm` package.
+
+Implementation would take place in the cli itself.
+
+For `npm dist-tag` it would mean iterating through each tag specified
+and making a new request to the registry.  The current registry endpoint
+for adding a dist-tag only operates on one tag at a time.  This also
+means that "rolling back" from an error is not very feasible, as it
+would mean for example attempting to delete any tags already added if
+one failed, and that is problematic if the tag is `latest`.
+
+For `npm publish` it would mean adding the dist-tags to the packument
+being uploaded at publish time. Multiple requests should not be needed.
+
+## Prior Art
+
+I am not aware of any package managers that interact with the npm
+registry that allow for this behavior. I looked at two as a small sample
+size:
+
+Currently yarnpkg also only allows for single-tag manipulation at one
+time via their `yarn tag add` and `yarn tag remove` commands, as well as with
+`yarn publish`.
+
+pnpm also only allows for a single tag during publishing, and does not
+appear to have an analog for `npm dist-tag`
+
+## Unresolved Questions and Bikeshedding
+
+Do we want a new parameter `--tags` instead? My first reaction is that
+we don't but it is worth discussing.
+
+How do we feel about the fact that rollbacks are not going to be
+feasible with adding and removing tags?