A merge on the operator's Approve into a repository the mesh builds nothing from asks the first build of the modules it holds (issue 1146, AC6, AC7)

cmd/mesh-controller/first_builds.go

@@ -0,0 +1,98 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// firstBuildWait is how long after the forge made a merge the controller keeps hearing it again for mesh-delivery's word
+// on it, which may be on its way when the forge's announcement is heard (novox/hq ADR 0432).
+const firstBuildWait = 2 * time.Minute
+
+// firstBuilds asks the first build of every module a merge adds to a repository no registered module is built from, when
+// the merge was announced as made on the operator's Approve of that head (novox/hq ADR 0432, issue 1146): the modules'
+// directories are the ones the announcement says hold a module.json at the merge commit, as touchedBy reads them. The
+// merge is kept, so the build's outcome is judged by the rule that registers it (mayRegisterFrom, approvedMove). Without
+// the Approve nothing is asked, and it says why. Answers whether the merge was dealt with here.
+func (f following) firstBuilds(ctx context.Context, m link.SourceMoved, entries []inventory.Entry,
+	read map[string][]inventory.ReadRepository, now time.Time) (bool, error) {
+	inv := f.open.inventory
+	repository := m.Owner + "/" + m.Repo
+	added, why, err := firstBuildsOf(ctx, inv, m, entries, read, now)
+	switch {
+	case errors.Is(err, errFirstNotApproved):
+		fmt.Printf("%s merged into %s (%.8s) adds %s, and no build is asked: %v\n", repository, m.Base, m.Commit,
+			strings.Join(addedDirs(m, entries, read), ", "), err)
+		return true, nil
+	case err != nil:
+		return true, notNow(err)
+	case len(added) == 0:
+		return false, nil
+	}
+	merged, err := time.Parse(time.RFC3339Nano, m.MergedAt)
+	if err != nil {
+		merged = now
+	}
+	event, err := json.Marshal(keptMerge{SourceMoved: m})
+	if err != nil {
+		return true, err
+	}
+	if _, err := inv.AddMerge(ctx, inventory.BatchedMerge{Repository: repository, Branch: m.Base, Commit: m.Commit,
+		Merged: merged.UTC(), Heard: now, Event: event}); err != nil {
+		return true, notNow(err)
+	}
+	fmt.Printf("%s merged into %s (%.8s) on the operator's Approve (%s): the mesh builds nothing from it yet, so the "+
+		"first build of %s is asked\n", repository, m.Base, m.Commit, why, strings.Join(added, ", "))
+	askBuilds(ctx, inv, m, buildSource{Repository: repository, Seat: gitSeat}, added)
+	return true, nil
+}
+
+// errFirstNotApproved says a merge into a repository the mesh builds nothing from is not one the operator approved.
+var errFirstNotApproved = errors.New("it is no merge made on the operator's Approve of its head, so a hand `build` " +
+	"registers a module from a repository the mesh does not build yet")
+
+// addedDirs are the module directories the merge adds to a repository no registered module is built from, none where
+// the merge is not into the trunk or some module is built from the repository already.
+func addedDirs(m link.SourceMoved, entries []inventory.Entry, read map[string][]inventory.ReadRepository) []string {
+	if m.Base != "main" {
+		return nil
+	}
+	for _, e := range entries {
+		if !e.Provided && sameRepository(e.Source.Repository, m) {
+			return nil
+		}
+	}
+	_, added, _ := touchedBy(nil, entries, m, read)
+	return added
+}
+
+// firstBuildsOf is the directories whose first build a merge asks, and the warrant it was made on; none when the merge
+// is no first merge into a repository the mesh builds nothing from. errFirstNotApproved when it is, and the operator's
+// Approve of its head is not on record, a try-again error while mesh-delivery's word may still be on its way.
+func firstBuildsOf(ctx context.Context, inv catalogueReader, m link.SourceMoved, entries []inventory.Entry,
+	read map[string][]inventory.ReadRepository, now time.Time) ([]string, string, error) {
+	added := addedDirs(m, entries, read)
+	if len(added) == 0 {
+		return nil, "", nil
+	}
+	why, err := approvedAnnounced(ctx, inv, m.Owner, m.Repo, keptMerge{SourceMoved: m})
+	if err == nil {
+		return added, why, nil
+	}
+	merged, perr := time.Parse(time.RFC3339Nano, m.MergedAt)
+	if errors.Is(err, errNotAnnounced) && perr == nil && now.Sub(merged) < firstBuildWait {
+		return nil, "", fmt.Errorf("%w: %w", link.ErrTryAgain, err)
+	}
+	var nope error = fmt.Errorf("%w (%v)", errFirstNotApproved, err)
+	if inventory.Unreachable(err) {
+		nope = err
+	}
+	return nil, "", nope
+}