fix(discov): move etcd hosts from URI authority to path for Go 1.26 compatibility (#5548)

zrpc/resolver/internal/targets/endpoints.go

@@ -17,3 +17,29 @@ func GetAuthority(target resolver.Target) string {
 func GetEndpoints(target resolver.Target) string {
 	return strings.Trim(target.URL.Path, slashSeparator)
 }
+
+// GetHosts returns the comma-separated etcd hosts from the target URL.
+// It supports two formats:
+//   - New format (etcd:///h1:port,h2:port?key=k): hosts are in the URL path (empty authority)
+//   - Legacy format (etcd://h1:port/key): host is in the URL authority
+func GetHosts(target resolver.Target) string {
+	if target.URL.Host == "" {
+		// New format: hosts encoded in URL path to avoid RFC 3986 authority issues
+		return GetEndpoints(target)
+	}
+	// Legacy format: single host in authority
+	return target.URL.Host
+}
+
+// GetKey returns the etcd key from the target URL.
+// It supports two formats:
+//   - New format (etcd:///h1:port,h2:port?key=k): key is in the "key" query parameter
+//   - Legacy format (etcd://h1:port/key): key is in the URL path
+func GetKey(target resolver.Target) string {
+	if target.URL.Host == "" {
+		// New format: key is in the query parameter
+		return target.URL.Query().Get("key")
+	}
+	// Legacy format: key is in the path
+	return strings.Trim(target.URL.Path, slashSeparator)
+}

zrpc/resolver/internal/targets/endpoints_test.go

@@ -87,3 +87,83 @@ func TestGetEndpoints(t *testing.T) {
 		})
 	}
 }
+
+func TestGetHosts(t *testing.T) {
+	tests := []struct {
+		name string
+		url  string
+		want string
+	}{
+		{
+			name: "single host",
+			url:  "etcd:///localhost:2379?key=foo",
+			want: "localhost:2379",
+		},
+		{
+			name: "multiple hosts",
+			url:  "etcd:///host1:2379,host2:2379,host3:2379?key=foo",
+			want: "host1:2379,host2:2379,host3:2379",
+		},
+		{
+			name: "legacy single host in authority",
+			url:  "etcd://localhost:2379/my-service",
+			want: "localhost:2379",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			uri, err := url.Parse(test.url)
+			assert.Nil(t, err)
+			target := resolver.Target{
+				URL: *uri,
+			}
+			assert.Equal(t, test.want, GetHosts(target))
+		})
+	}
+}
+
+func TestGetKey(t *testing.T) {
+	tests := []struct {
+		name string
+		url  string
+		want string
+	}{
+		{
+			name: "simple key",
+			url:  "etcd:///localhost:2379?key=my-service",
+			want: "my-service",
+		},
+		{
+			name: "key with slashes",
+			url:  "etcd:///localhost:2379?key=%2Fgrpc%2Fmy-service",
+			want: "/grpc/my-service",
+		},
+		{
+			name: "no key",
+			url:  "etcd:///localhost:2379",
+			want: "",
+		},
+		{
+			name: "legacy key in path",
+			url:  "etcd://localhost:2379/my-service",
+			want: "my-service",
+		},
+		{
+			name: "legacy key with leading slash",
+			url:  "etcd://localhost:2379/grpc/my-service",
+			want: "grpc/my-service",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			uri, err := url.Parse(test.url)
+			assert.Nil(t, err)
+			target := resolver.Target{
+				URL: *uri,
+			}
+			assert.Equal(t, test.want, GetKey(target))
+		})
+	}
+}