feat(examples): use protobufjs with multiple proto targets

examples/protobufjs/BUILD.bazel

@@ -5,26 +5,40 @@ load(":defs.bzl", "protobufjs_library")
 
 proto_library(
     name = "car_proto",
-    srcs = [
-        "car.proto",
-        "tire.proto",
-    ],
+    srcs = ["car.proto"],
+    deps = [":tire_proto"],
+)
+
+proto_library(
+    name = "tire_proto",
+    srcs = ["tire.proto"],
+)
+
+proto_library(
+    name = "animal_proto",
+    srcs = ["animal.proto"],
 )
 
 protobufjs_library(
     # produces outputs named after this,
-    # car.d.ts and car.js
-    name = "car",
-    proto = "car_proto",
+    # "car_and_animal.d.ts" and "car_and_animal.js".
+    name = "car_and_animal",
+    protos = [
+        ":animal_proto",
+        ":car_proto",
+    ],
 )
 
 ts_project(
     name = "test_lib",
     testonly = True,
-    srcs = ["car.spec.ts"],
+    srcs = [
+        "animal.spec.ts",
+        "car.spec.ts",
+    ],
     tsconfig = "tsconfig.json",
     deps = [
-        ":car",
+        ":car_and_animal",
         "@npm//@types/jasmine",
         "@npm//protobufjs",
     ],
@@ -37,7 +51,7 @@ ts_project(
     ],
     tsconfig = "//:tsconfig.json",
     deps = [
-        ":car",
+        ":car_and_animal",
         "@npm//protobufjs",
     ],
 )

examples/protobufjs/animal.proto

@@ -0,0 +1,8 @@
+syntax = "proto3";
+
+package Proto;
+
+message Animal {
+  string name = 1;
+  bool has_fur = 2;
+}

examples/protobufjs/animal.spec.ts

@@ -0,0 +1,10 @@
+import {Proto as pb} from './car_and_animal_pb';
+
+describe('protocol buffers', () => {
+  it('allows creation of an object described by proto', () => {
+    const animal = pb.Animal.create({name: "cat", hasFur: true});
+
+    expect(animal.name).toEqual("cat");
+    expect(animal.hasFur).toEqual(true);
+  });
+});

examples/protobufjs/car.spec.ts

@@ -1,4 +1,4 @@
-import {Proto as pb} from './car_pb';
+import {Proto as pb} from './car_and_animal_pb';
 
 describe('protocol buffers', () => {
   it('allows creation of an object described by proto', () => {

examples/protobufjs/defs.bzl

@@ -17,42 +17,48 @@ _proto_sources = rule(
     attrs = {"proto": attr.label(providers = [ProtoInfo])},
 )
 
-def protobufjs_library(name, proto, **kwargs):
+def _sanitize_label(label_string):
+    """Replace characters in a label so it can be used as part of a target name."""
+    return label_string.replace(":", "_").replace("/", "_")
+
+def protobufjs_library(name, protos, **kwargs):
     """Minimal wrapper macro around pbjs/pbts tooling
 
     Args:
         name: name of generated js_library target, also used to name the .js/.d.ts outputs
-        proto: label of a single proto_library target to generate for
+        protos: labels of proto_library targets to generate for
         **kwargs: passed through to the js_library
     """
 
     js_out = name + "_pb.js"
     ts_out = js_out.replace(".js", ".d.ts")
 
-    # Generate some target names, based on the provided name
-    # (so that they are unique if the macro is called several times in one package)
-    proto_target = "_%s_protos" % name
     js_target = "_%s_pbjs" % name
     ts_target = "_%s_pbts" % name
 
+    # Generate some target names, based on the provided name
+    # (so that they are unique if the macro is called several times in one package)
+    proto_targets = ["_%s_%s" % (name, _sanitize_label(proto)) for proto in protos]
+
     # grab the transitive .proto files needed to compile the given one
-    _proto_sources(
-        name = proto_target,
-        proto = proto,
-    )
+    for proto, proto_target in zip(protos, proto_targets):
+        _proto_sources(
+            name = proto_target,
+            proto = proto,
+        )
 
     # Transform .proto files to a single _pb.js file named after the macro
     pbjs(
         name = js_target,
-        data = [proto_target],
+        data = proto_targets,
         # Arguments documented at
         # https://github.com/protobufjs/protobuf.js/tree/6.8.8#pbjs-for-javascript
         args = [
             "--target=static-module",
             "--wrap=default",
             "--strict-long",  # Force usage of Long type with int64 fields
             "--out=$@",
-            "$(execpaths %s)" % proto_target,
+            " ".join(["$(execpaths %s)" % proto_target for proto_target in proto_targets]),
         ],
         outs = [js_out],
     )