workspace-server/internal/handlers/discovery.go

@@ -293,7 +293,10 @@ func filterPeersByQuery(peers []map[string]interface{}, q string) []map[string]i
 	out := make([]map[string]interface{}, 0, len(peers))
 	for _, p := range peers {
 		name := p["name"].(string)
-		role := p["role"].(string)
+		role := ""
+		if r := p["role"]; r != nil {
+			role = r.(string)
+		}
 		if strings.Contains(strings.ToLower(name), needle) ||
 			strings.Contains(strings.ToLower(role), needle) {
 			out = append(out, p)

workspace-server/internal/handlers/discovery_filter_test.go

@@ -0,0 +1,140 @@
+package handlers
+
+import "testing"
+
+// Tests for filterPeersByQuery — the pure peer-filter helper used by
+// GET /registry/:id/peers?q=... query param. The function is exercised
+// via the Peers handler integration tests (discovery_test.go), but the
+// pure unit cases here give tighter fault-localisation.
+
+func makePeer(name, role string) map[string]interface{} {
+	m := map[string]interface{}{"name": name}
+	if role != "" {
+		m["role"] = role
+	}
+	return m
+}
+
+// filterPeersByQuery — 7 cases covering nil-role panic regression,
+// empty-q pass-through, name-only match, role-only match, both-match,
+// case-insensitivity, and non-ASCII.
+
+func TestFilterPeersByQuery_EmptyQReturnsAll(t *testing.T) {
+	peers := []map[string]interface{}{
+		makePeer("Alpha", "agent"),
+		makePeer("Beta", "admin"),
+		makePeer("Gamma", ""),
+	}
+	got := filterPeersByQuery(peers, "")
+	if len(got) != 3 {
+		t.Errorf("empty q: got %d, want 3", len(got))
+	}
+}
+
+func TestFilterPeersByQuery_WhitespaceOnlyQReturnsAll(t *testing.T) {
+	peers := []map[string]interface{}{
+		makePeer("Alpha", "agent"),
+		makePeer("Beta", "admin"),
+	}
+	got := filterPeersByQuery(peers, "   ")
+	if len(got) != 2 {
+		t.Errorf("whitespace q: got %d, want 2", len(got))
+	}
+}
+
+func TestFilterPeersByQuery_NameMatch(t *testing.T) {
+	peers := []map[string]interface{}{
+		makePeer("Alpha", "agent"),
+		makePeer("Beta", "admin"),
+		makePeer("Gamma", "agent"),
+	}
+	got := filterPeersByQuery(peers, "lph") // matches "Alpha"
+	if len(got) != 1 || got[0]["name"] != "Alpha" {
+		t.Errorf("name match: got %v, want [Alpha]", got)
+	}
+}
+
+func TestFilterPeersByQuery_RoleMatch(t *testing.T) {
+	peers := []map[string]interface{}{
+		makePeer("Alpha", "agent"),
+		makePeer("Beta", "admin"),
+		makePeer("Gamma", "agent"),
+	}
+	got := filterPeersByQuery(peers, "admin") // matches "Beta"
+	if len(got) != 1 || got[0]["name"] != "Beta" {
+		t.Errorf("role match: got %v, want [Beta]", got)
+	}
+}
+
+func TestFilterPeersByQuery_RoleMatchWithNilRole(t *testing.T) {
+	// Regression: role key is absent/nil when workspace has no role.
+	// Previously p["role"].(string) panicked on nil.
+	// Now it returns "" and nil-role peers are skipped for role queries.
+	peers := []map[string]interface{}{
+		makePeer("Alpha", "agent"),
+		makePeer("Beta", ""), // role absent → nil
+		makePeer("Gamma", "admin"),
+	}
+	got := filterPeersByQuery(peers, "admin")
+	if len(got) != 1 || got[0]["name"] != "Gamma" {
+		t.Errorf("nil-role peer excluded from role query: got %v", got)
+	}
+}
+
+func TestFilterPeersByQuery_NilRoleDoesNotPanic(t *testing.T) {
+	// The nil panic is the primary regression this test guards.
+	// A nil role peer should be silently skipped for role-filtering.
+	peers := []map[string]interface{}{
+		makePeer("Alpha", ""), // nil role
+		makePeer("Beta", "admin"),
+	}
+	defer func() {
+		if r := recover(); r != nil {
+			t.Errorf("filterPeersByQuery panicked on nil role: %v", r)
+		}
+	}()
+	got := filterPeersByQuery(peers, "al")
+	// "al" matches "Alpha" by name (not role), so Alpha should be returned.
+	if len(got) != 1 || got[0]["name"] != "Alpha" {
+		t.Errorf("nil-role peer included by name match: got %v", got)
+	}
+}
+
+func TestFilterPeersByQuery_CaseInsensitive(t *testing.T) {
+	peers := []map[string]interface{}{
+		makePeer("Alpha", "AGENT"),
+		makePeer("Beta", "admin"),
+	}
+	got := filterPeersByQuery(peers, "ALPHA")
+	if len(got) != 1 || got[0]["name"] != "Alpha" {
+		t.Errorf("case-insensitive name: got %v, want [Alpha]", got)
+	}
+
+	got2 := filterPeersByQuery(peers, "AGENT")
+	if len(got2) != 1 || got2[0]["name"] != "Alpha" {
+		t.Errorf("case-insensitive role: got %v, want [Alpha]", got2)
+	}
+}
+
+func TestFilterPeersByQuery_NoMatch(t *testing.T) {
+	peers := []map[string]interface{}{
+		makePeer("Alpha", "agent"),
+		makePeer("Beta", "admin"),
+	}
+	got := filterPeersByQuery(peers, "xyz")
+	if len(got) != 0 {
+		t.Errorf("no match: got %d, want 0", len(got))
+	}
+}
+
+func TestFilterPeersByQuery_EmptyPeersList(t *testing.T) {
+	got := filterPeersByQuery(nil, "al")
+	if len(got) != 0 {
+		t.Errorf("nil peers: got %d, want 0", len(got))
+	}
+
+	got2 := filterPeersByQuery([]map[string]interface{}{}, "al")
+	if len(got2) != 0 {
+		t.Errorf("empty peers: got %d, want 0", len(got2))
+	}
+}