Retrieving push metainformation and transferring it to the CI

I know, that in general GitLab CI scripts run after every push to the repository. How I can retrieve metainforation about the push and then transfer it to the GitLab CI?

By metainforation I mean:

• project name,
• name of the user, who performed this push,
• name of the branch (branches) affected by push.

You can find an overview of variables available in the CI here: https://docs.gitlab.com/ee/ci/variables/#predefined-variables-environment-variables.

E.g.:

• CI_COMMIT_REF_NAME | The branch or tag name for which project is built
• CI_PROJECT_NAME | The project name that is currently being built (actually it is project folder name)
• GITLAB_USER_ID | The id of the user who started the job
• GITLAB_USER_EMAIL | The email of the user who started the job