Update importer docs for user contribution mapping

GitLab.com has the improved user contribution mapping enabled for GitHub, Bitbucket Server and Gitea importers. This docs change refactors these importers to have a common section, and updates old information regarding user mapping to signal this is available on Self-managed and Dedicated only now. https://gitlab.com/groups/gitlab-org/-/epics/14667

Update importer docs for user contribution mapping
2ec81ffb · Luke Duncalfe · GitLab · 25b661ad · 2ec81ffb · 2ec81ffb
--- a/doc/user/project/import/bitbucket_server.md
+++ b/doc/user/project/import/bitbucket_server.md
@@ -17,11 +17,6 @@ DETAILS:
 Import your projects from Bitbucket Server to GitLab.
-WARNING:
-Importing from Bitbucket Server to GitLab.com is [unavailable](https://status.gitlab.com).
-For more information, contact [GitLab Support](https://about.gitlab.com/support/).
-[Importing from Bitbucket Cloud](bitbucket.md) is not affected.
 ## Prerequisites
 > - Requirement for Maintainer role instead of Developer role introduced in GitLab 16.0 and backported to GitLab 15.11.1 and GitLab 15.10.5.
@@ -90,18 +85,26 @@ The following items are changed when they are imported:
 - Project filtering doesn't support fuzzy search. Only **starts with** or **full match** strings are
  supported.
-## User assignment
+## User contribution mapping
 > - User mapping by email address or username [introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/36885) in GitLab 13.4 [with a flag](../../../administration/feature_flags.md) named `bitbucket_server_user_mapping_by_username`. Disabled by default.
 > - Mapping user mentions to GitLab users [added](https://gitlab.com/gitlab-org/gitlab/-/issues/433008) in GitLab 16.8.
 > - [Changed](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/153041) to map users only by email address in GitLab 17.1.
+> - [Changed on GitLab.com](https://gitlab.com/groups/gitlab-org/-/epics/14667) to [User contribution and membership mapping](../import/index.md#user-contribution-and-membership-mapping) in 17.8.
+The Bitbucket Server importer uses [an improved method](../import/index.md#user-contribution-and-membership-mapping)
+of mapping user contributions for:
+- GitLab.com
+- GitLab self-managed 17.7 or later when the `importer_user_mapping` and `bitbucket_server_user_mapping` feature flags are enabled.
+### Old method of user contribution mapping
-FLAG:
+You can use the old user contribution mapping method for imports to GitLab self-managed and GitLab Dedicated instances. For imports to GitLab.com, you must
-The availability of this feature is controlled by a feature flag.
+use [the improved method](../import/index.md#user-contribution-and-membership-mapping) instead.
-For more information, see the history.
-When issues and pull requests are importing, the importer tries to match a Bitbucket Server user's email address
+Using the old method, the importer tries to match a Bitbucket Server user's email address with a confirmed email address in the GitLab user database. If no
-with a confirmed email address in the GitLab user database. If no such user is found:
+such user is found:
 - The project creator is used instead. The importer appends a note in the comment to mark the original creator.
 - For pull request reviewers, no reviewer is assigned.

--- a/doc/user/project/import/gitea.md
+++ b/doc/user/project/import/gitea.md
@@ -16,10 +16,6 @@ DETAILS:
 Import your projects from Gitea to GitLab.
-WARNING:
-Importing from Gitea to GitLab.com is [unavailable](https://status.gitlab.com).
-For more information, contact [GitLab Support](https://about.gitlab.com/support/).
 The Gitea importer can import:
 - Repository description
@@ -95,9 +91,17 @@ You also can:
 ## User contribution mapping
-User contributions are assigned to the project creator (usually the user who started the import process) by default.
+> - [Changed on GitLab.com](https://gitlab.com/groups/gitlab-org/-/epics/14667) to [User contribution and membership mapping](../import/index.md#user-contribution-and-membership-mapping) in 17.8.
-This method of user contribution mapping is available for GitLab self-managed without enabled feature flags.
+The Gitea importer uses [an improved method](../import/index.md#user-contribution-and-membership-mapping)
+of mapping user contributions for:
+- GitLab.com
+- GitLab self-managed 17.6 or later when the `importer_user_mapping` and `gitea_user_mapping` feature flags are enabled.
+### Old method of user contribution mapping
+You can use the old user contribution mapping method for imports to GitLab self-managed and GitLab Dedicated instances. For imports to GitLab.com, you must
+use [the improved method](../import/index.md#user-contribution-and-membership-mapping) instead.
-For information on the other method available for GitLab self-managed
+Using the old method, user contributions are assigned to the project creator (usually the user who started the import process) by default.
-with enabled feature flags and for GitLab.com,
-see [user contribution and membership mapping](../../project/import/index.md#user-contribution-and-membership-mapping).
--- a/doc/user/project/import/github.md
+++ b/doc/user/project/import/github.md
@@ -17,10 +17,6 @@ DETAILS:
 You can import your GitHub projects from either GitHub.com or GitHub Enterprise. Importing projects does not
 migrate or import any types of groups or organizations from GitHub to GitLab.
-WARNING:
-Importing from GitHub to GitLab.com is [unavailable](https://status.gitlab.com).
-For more information, contact [GitLab Support](https://about.gitlab.com/support/).
 Imported issues, merge requests, comments, and events have an **Imported** badge in GitLab.
 The namespace is a user or group in GitLab, such as `gitlab.com/sidney-jones` or
@@ -66,7 +62,13 @@ on the GitLab instance you import to.
 ### Accounts for user contribution mapping
-For user contribution mapping between GitHub and GitLab to work:
+> - [Preparation requirement removed on GitLab.com](https://gitlab.com/groups/gitlab-org/-/epics/14667) in GitLab 17.8.
+Before using [the old method of user contribution mapping](#old-method-of-user-contribution-mapping) for imports to GitLab self-managed and GitLab
+Dedicated, you must take meet certain requirements. Imports to GitLab.com use [an improved method](../import/index.md#user-contribution-and-membership-mapping)
+that doesn't require preparation.
+These requirements are:
 - Each GitHub author and assignee in the repository must have a
  [public-facing email address](https://docs.github.com/en/account-and-profile/setting-up-and-managing-your-personal-account-on-github/managing-email-preferences/setting-your-commit-email-address).
@@ -75,18 +77,6 @@ For user contribution mapping between GitHub and GitLab to work:
 GitHub Enterprise does not require a public email address, so you might have to add it to existing accounts.
-If the above requirements are not met, the importer can't map the particular user's contributions. In that case:
- The project creator is set as the author and assignee of issues and merge requests. The project creator is usually the
-  user that initiated the import process. For some contributions that have a description or note such as pull requests,
-  issue, notes, the importer amends the text with details of who originally created the contribution.
- Reviewers and approvals added on pull requests in GitHub cannot be imported. In this case, the importer creates comments
-  describing that non-existent users were added as reviewers and approvers. However, the actual reviewer status and
-  approval are not applied to the merge request in GitLab.
-[In GitLab 17.5 and later](https://gitlab.com/gitlab-org/gitlab/-/issues/477553), GitLab adds backticks to username mentions in issues, merge requests, and notes.
-These backticks prevent linking to an incorrect user with the same username on the GitLab instance.
 ## Known issues
 - GitHub pull request comments (known as diff notes in GitLab) created before 2017 are imported in separate threads.
@@ -108,15 +98,6 @@ These backticks prevent linking to an incorrect user with the same username on t
 ## Import your GitHub repository into GitLab
-Before you begin, ensure that any GitHub user you want to map to a GitLab user
-has a GitLab email address that matches their
-[publicly visible email address](https://docs.github.com/en/rest/users#get-a-user)
-on GitHub.
-If a GitHub user's public email address doesn't match any GitLab user email
-address, the user's activity is associated with the user account that is
-performing the import.
 You can import your GitHub repository by either:
 - [Using GitHub OAuth](#use-github-oauth)
@@ -257,6 +238,39 @@ After imports are completed, they can be in one of three states:
 Expand **Details** to see a list of [repository entities](#imported-data) that failed to import.
+## Username mentions
+> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/477553) in GitLab 17.5.
+GitLab adds backticks to username mentions in issues, merge requests, and notes.
+These backticks prevent linking to an incorrect user with the same username on the GitLab instance.
+## User contribution mapping
+> - [Changed on GitLab.com](https://gitlab.com/groups/gitlab-org/-/epics/14667) to [User contribution and membership mapping](../import/index.md#user-contribution-and-membership-mapping) in 17.8.
+The GitHub importer uses [an improved method](../import/index.md#user-contribution-and-membership-mapping)
+of mapping user contributions for:
+- GitLab.com
+- GitLab self-managed 17.6 or later when the `importer_user_mapping` and `github_user_mapping` feature flags are enabled.
+### Old method of user contribution mapping
+You can use the old user contribution mapping method for imports to GitLab self-managed and GitLab Dedicated instances. For imports to GitLab.com, you must
+use [the improved method](../import/index.md#user-contribution-and-membership-mapping) instead.
+Using the old method, when [user accounts are provisioned correctly](#accounts-for-user-contribution-mapping), users are mapped during the import.
+If the requirements are not met, the importer can't map the particular user's contributions. In that case:
+- The project creator is set as the author and assignee of issues and merge requests. The project creator is usually the
+  user that initiated the import process. For some contributions that have a description or note such as pull requests,
+  issue, notes, the importer amends the text with details of who originally created the contribution.
+- Reviewers and approvals added on pull requests in GitHub cannot be imported. In this case, the importer creates comments
+  describing that non-existent users were added as reviewers and approvers. However, the actual reviewer status and
+  approval are not applied to the merge request in GitLab.
 ## Mirror a repository and share pipeline status
 DETAILS: