test(e2e): entrypoint ERR trap and richer CI failure logs

CI showed exit=1 in ~3s with empty docker logs after /data/opendkim was
created. Log each entrypoint step and trap ERR with LINENO; also read the
container LogPath and docker logs by container id when compose logs are empty.

Co-Authored-By: Composer <noreply@cursor.com>
Co-authored-by: Cursor <cursoragent@cursor.com>

test/e2e/hostname_gate_test.go

@@ -128,6 +128,21 @@ func runEntrypointBackground(t *testing.T, hostnameEnv string) (output string, s
 	inspect, _ := exec.Command("docker", "inspect", name, "--format",
 		"status={{.State.Status}} exit={{.State.ExitCode}} err={{.State.Error}} oom={{.State.OOMKilled}} started={{.State.StartedAt}} finished={{.State.FinishedAt}}").CombinedOutput()
 	logs, logErr := exec.Command("docker", "logs", name).CombinedOutput()
+	// Exited containers sometimes yield empty `docker logs` in CI; also read
+	// the JSON-file log path docker recorded on the container.
+	logPathOut, _ := exec.Command("docker", "inspect", name, "--format", "{{.LogPath}}").CombinedOutput()
+	logPath := strings.TrimSpace(string(logPathOut))
+	logFileHead := ""
+	if logPath != "" {
+		if b, e := os.ReadFile(logPath); e == nil {
+			logFileHead = truncateForDebug(string(b), 4000)
+			if strings.TrimSpace(string(logs)) == "" && len(b) > 0 {
+				logs = b
+			}
+		} else {
+			logFileHead = "read LogPath: " + e.Error()
+		}
+	}
 	dataMode, _ := exec.Command("docker", "exec", name, "stat", "-c", "%a %U:%G", "/data").CombinedOutput()
 	opendkimStat, _ := exec.Command("docker", "exec", name, "stat", "-c", "%a %U:%G", "/data/opendkim").CombinedOutput()
 	keyTableStat, _ := exec.Command("docker", "exec", name, "stat", "-c", "%a %U:%G", "/data/opendkim/KeyTable").CombinedOutput()
@@ -147,16 +162,18 @@ func runEntrypointBackground(t *testing.T, hostnameEnv string) (output string, s
 		hostDataListing = strings.Join(parts, ",")
 	}
 	agentDebugLog("H1", "hostname_gate_test.go:post-wait", "data permissions", map[string]any{
-		"dataMode":      strings.TrimSpace(string(dataMode)),
-		"opendkimStat":  strings.TrimSpace(string(opendkimStat)),
-		"keyTableStat":  strings.TrimSpace(string(keyTableStat)),
+		"dataMode":        strings.TrimSpace(string(dataMode)),
+		"opendkimStat":    strings.TrimSpace(string(opendkimStat)),
+		"keyTableStat":    strings.TrimSpace(string(keyTableStat)),
 		"hostDataListing": hostDataListing,
 	})
 	agentDebugLog("H2", "hostname_gate_test.go:post-wait", "container inspect", map[string]any{
-		"inspect": strings.TrimSpace(string(inspect)),
-		"waitErr": fmt.Sprintf("%v", err),
-		"logErr":  fmt.Sprintf("%v", logErr),
-		"logLen":  len(logs),
+		"inspect":    strings.TrimSpace(string(inspect)),
+		"waitErr":    fmt.Sprintf("%v", err),
+		"logErr":     fmt.Sprintf("%v", logErr),
+		"logLen":     len(logs),
+		"logPath":    logPath,
+		"logFileHead": logFileHead,
 	})
 	agentDebugLog("H3", "hostname_gate_test.go:post-wait", "supervisor and logs", map[string]any{
 		"supervisorctl": strings.TrimSpace(string(supStatus)),
@@ -167,8 +184,11 @@ func runEntrypointBackground(t *testing.T, hostnameEnv string) (output string, s
 	diag := string(logs)
 	if strings.TrimSpace(diag) == "" {
 		diag = "(empty docker logs)\ninspect: " + strings.TrimSpace(string(inspect)) +
+			"\nlogPath: " + logPath +
+			"\nlogFileHead: " + logFileHead +
 			"\nsupervisorctl: " + strings.TrimSpace(string(supStatus)) +
-			"\n/data mode: " + strings.TrimSpace(string(dataMode))
+			"\n/data mode: " + strings.TrimSpace(string(dataMode)) +
+			"\nhost /data: " + hostDataListing
 	}
 	return diag, err == nil
 }

test/e2e/process_check.go

@@ -54,17 +54,36 @@ func checkSupervisorProcesses(s *stack) error {
 		ps, _ := s.compose("ps", "-a", "--format", "json")
 		inspectOut, _ := exec.Command("docker", "ps", "-a", "--filter", "name=selfpost-e2e",
 			"--format", "{{.Names}} {{.Status}} {{.ID}}").CombinedOutput()
+		// compose logs can be empty for a fast-exit container; pull docker logs by id.
+		rawDockerLogs := ""
+		for _, line := range strings.Split(string(inspectOut), "\n") {
+			fields := strings.Fields(line)
+			if len(fields) < 3 || !strings.Contains(fields[0], "selfpost-1") {
+				continue
+			}
+			id := fields[len(fields)-1]
+			if b, e := exec.Command("docker", "logs", id).CombinedOutput(); e == nil {
+				rawDockerLogs = string(b)
+			} else {
+				rawDockerLogs = e.Error() + "\n" + string(b)
+			}
+			if strings.TrimSpace(logs) == "" && strings.TrimSpace(rawDockerLogs) != "" {
+				logs = rawDockerLogs
+			}
+			break
+		}
 		dataPath := filepath.Join(s.stageDir, "data")
 		dataMode := ""
 		if fi, e := os.Stat(dataPath); e == nil {
 			dataMode = fmt.Sprintf("%04o", fi.Mode().Perm())
 		}
 		entrypointSnippet, _ := exec.Command("docker", "run", "--rm", "--entrypoint", "sh", "selfpost:e2e",
-			"-c", "grep -n 'chmod 755 /data\\|SELFPOST_HOSTNAME is not set' /usr/local/bin/entrypoint.sh | head -20").CombinedOutput()
+			"-c", "grep -n 'chmod 755 /data\\|entrypoint: command failed\\|step()' /usr/local/bin/entrypoint.sh | head -30").CombinedOutput()
 		agentDebugLog("H4", "process_check.go:fail", "compose selfpost not ready", map[string]any{
 			"waitErr":            err.Error(),
 			"logsLen":            len(logs),
 			"logsHead":           truncateForDebug(logs, 4000),
+			"rawDockerLogsHead":  truncateForDebug(rawDockerLogs, 4000),
 			"composePs":          truncateForDebug(string(ps), 2000),
 			"dockerPs":           strings.TrimSpace(string(inspectOut)),
 			"hostDataMode":       dataMode,
@@ -74,8 +93,8 @@ func checkSupervisorProcesses(s *stack) error {
 			"snippet": strings.TrimSpace(string(entrypointSnippet)),
 		})
 		// #endregion
-		return fmt.Errorf("%w\n==== selfpost logs ====\n%s\n==== docker ps ====\n%s\n==== entrypoint markers ====\n%s",
-			err, logs, inspectOut, entrypointSnippet)
+		return fmt.Errorf("%w\n==== selfpost logs ====\n%s\n==== docker logs (by id) ====\n%s\n==== docker ps ====\n%s\n==== entrypoint markers ====\n%s",
+			err, logs, rawDockerLogs, inspectOut, entrypointSnippet)
 	}
 	return nil
 }