[mike@mwxm4]

deleteremote.go

@@ -0,0 +1,184 @@
+package main
+
+// deleteremote.go — the `deleteremote` command: remove the active project's
+// repository from a public mirror server via that server's REST API.
+//
+// This is the only mgsh command that destroys something on a server it does not
+// own, and nothing here can undo it. Four things keep it in check:
+//
+//   - the server has to be named. `pushremote` without one means "every
+//     configured target", which is convenient there and catastrophic here.
+//   - the repository is looked up first, so a typo comes back as "not on that
+//     server" instead of as a DELETE nobody meant to send.
+//   - every deletion is confirmed on its own, spelling out owner/repo and the
+//     server it lives on, and the default answer is no.
+//   - the local clone is never touched. Only the git remote `pushremote`
+//     created is dropped, and only while it still points at what was deleted.
+
+import (
+	"fmt"
+	"strings"
+)
+
+// deleteRepo removes owner/repo from the server.
+//
+// The providers disagree on what success looks like: Gitea and GitHub answer
+// 204, GitLab 202 — there the deletion is merely scheduled, and depending on
+// the plan the project stays visible until its retention period is over.
+func (r *remoteAPI) deleteRepo(owner, repo string) error {
+	code, data, err := r.do("DELETE", r.repoPath(owner, repo), nil)
+	if err != nil {
+		return err
+	}
+	switch code {
+	case 200, 202, 204:
+		return nil
+	case 403:
+		// the common failure by far: the token can push and create, but was
+		// never given the separate permission a deletion needs
+		return fmt.Errorf("not allowed to delete %s/%s — the token needs %s (HTTP 403): %s",
+			owner, repo, r.deletePermission(), firstLine(data))
+	default:
+		return fmt.Errorf("deleting repository failed (HTTP %d): %s", code, firstLine(data))
+	}
+}
+
+// deletePermission names what a provider wants from a token before it will
+// delete a repository, because a bare "403" sends people to the wrong setting.
+func (r *remoteAPI) deletePermission() string {
+	switch r.kind {
+	case kindGitHub:
+		return "the 'delete_repo' scope"
+	case kindGitLab:
+		return "the 'api' scope and the Owner role"
+	default: // Gitea
+		return "the 'write:repository' scope"
+	}
+}
+
+// parseRemoteSelectors splits `deleteremote <name|host> ...` into the targets
+// it names. The '@' that `pushremote` requires is accepted but optional here:
+// the command takes nothing but selectors, so there is no description a bare
+// word could be mistaken for.
+func parseRemoteSelectors(args string) []string {
+	var out []string
+	for _, f := range strings.Fields(args) {
+		if s := strings.TrimPrefix(f, "@"); s != "" {
+			out = append(out, s)
+		}
+	}
+	return out
+}
+
+// handleDeleteRemote implements `deleteremote <@name|host> ...`: it deletes the
+// active project's repository on each named mirror server.
+func handleDeleteRemote(args string) {
+	if !requireProject() {
+		return
+	}
+	targets, incomplete := cfg.mirrorTargets()
+	for _, n := range incomplete {
+		errorln("remote " + n + ": url or key missing — skipped")
+	}
+	if len(targets) == 0 {
+		errorln("deleteremote needs a 'remote.<name>.url' and 'remote.<name>.key' in " + configFile())
+		return
+	}
+
+	// no selector is never "all of them" — that is the whole point of the
+	// command taking one
+	sels := parseRemoteSelectors(args)
+	if len(sels) == 0 {
+		errorln("deleteremote needs the server to delete from: " + remoteChoices(targets))
+		return
+	}
+
+	targets = pickRemotes(targets, sels)
+	if len(targets) == 0 {
+		return // pickRemotes already named the selectors it did not recognise
+	}
+
+	repo := PRJ // like pushremote: the project names the repository
+	done := 0
+	for _, t := range targets {
+		if deleteOnRemote(t, repo) {
+			done++
+		}
+	}
+	if len(targets) > 1 {
+		fmt.Printf("%s %d/%d repositories deleted\n", col(cDark, "deleteremote:"), done, len(targets))
+	}
+}
+
+// remoteChoices lists the configured targets the way they may be selected, for
+// the message a `deleteremote` without a target earns.
+func remoteChoices(targets []RemoteTarget) string {
+	out := make([]string, 0, len(targets))
+	for _, t := range targets {
+		if h := remoteHost(t.URL); h != "" && !strings.EqualFold(h, t.Name) {
+			out = append(out, "@"+t.Name+" ("+h+")")
+			continue
+		}
+		out = append(out, "@"+t.Name)
+	}
+	return strings.Join(out, ", ")
+}
+
+// deleteOnRemote deletes repo on one target, after asking. It reports whether
+// something was actually deleted — a repository that is not there, and a
+// question answered with no, are not failures, and neither stops the remaining
+// targets.
+func deleteOnRemote(t RemoteTarget, repo string) bool {
+	api := newRemoteAPI(t.URL, t.Key, t.Type)
+
+	owner, err := api.authUser()
+	if err != nil {
+		errorln(t.Name + ": " + err.Error())
+		return false
+	}
+	fmt.Printf("%s %s %s (as %s)\n",
+		col(cDark, "remote"), col(cYellow, t.Name), col(cBlue, api.url), col(cGreen, owner))
+
+	exists, err := api.repoExists(owner, repo)
+	if err != nil {
+		errorln(t.Name + ": " + err.Error())
+		return false
+	}
+	if !exists {
+		fmt.Println(col(cDark, "no repository "+owner+"/"+repo+" there — nothing to delete"))
+		return false
+	}
+
+	fmt.Println(col(cOrange, "this deletes "+api.repoWebURL(owner, repo)+
+		" with its issues, releases and history, and cannot be undone"))
+	if !yesno("delete "+owner+"/"+repo+" on "+t.Name+"?", false) {
+		fmt.Println(col(cDark, "kept"))
+		return false
+	}
+
+	if err := api.deleteRepo(owner, repo); err != nil {
+		errorln(t.Name + ": " + err.Error())
+		return false
+	}
+	fmt.Println(col(cRed, "deleted ") + col(cWhite, owner+"/"+repo) + col(cDark, " on "+t.Name))
+
+	dropGitRemote(t.Name, api.repoWebURL(owner, repo))
+	return true
+}
+
+// dropGitRemote removes the local git remote named name, but only while it
+// still points at web — the repository just deleted. A remote the user has
+// since re-aimed somewhere else is theirs, not ours, and a `git push` failing
+// against a repository that no longer exists is worse than no remote at all.
+func dropGitRemote(name, web string) {
+	if !isDir(DIR + "/.git") {
+		return
+	}
+	url, err := gitCapture(DIR, "remote", "get-url", name)
+	if err != nil || strings.TrimSpace(url) != web {
+		return
+	}
+	if gitOK(DIR, "remote", "remove", name) {
+		fmt.Println(col(cDark, "removed git remote "+name))
+	}
+}