def ensure_commit(repo, sha, user, comments = true)
      ensure_repo(user, repo)
      c = retrieve_commit(repo, sha, user)

      if c.nil?
        warn "Commit #{user}/#{repo} -> #{sha} does not exist"
        return
      end

      stored = store_commit(c, repo, user)
      ensure_parents(c)
      if not c['commit']['comment_count'].nil? \
         and c['commit']['comment_count'] > 0
        ensure_commit_comments(user, repo, sha) if comments
      end
      ensure_repo_commit(user, repo, sha)
      stored
    end
def ensure_commit(repo, sha, user, comments = true)
      ensure_repo(user, repo)
      c = retrieve_commit(repo, sha, user)

      if c.nil?
        warn "Commit #{user}/#{repo} -> #{sha} does not exist"
        return
      end

      stored = store_commit(c, repo, user)
      ensure_parents(c)
      if not c['commit']['comment_count'].nil? \
         and c['commit']['comment_count'] > 0
        ensure_commit_comments(user, repo, sha) if comments
      end
      ensure_repo_commit(user, repo, sha)
      stored
    end
Make sure a commit exists