feat(options): adds protoc-gen-go-like M option (#672)

This commit adds a new feature that aims to provide the same
functionality as `M` for the go compiler (https://developers.google.com/protocol-buffers/docs/reference/go-generated#package).
I opted for not modifying the type map, because we'll also want to
figure out whether or not we need to generate the file, so we'll be
accessing the `options.M` everywhere and I found it less confusing to
always get mapping information from `options.M` instead of `options.M`
or the type map depending on the decision that we're making (we need to
know if we need to do a relative import or just the raw provided
import too).

Fixes #596

README.markdown

@@ -450,6 +450,14 @@ Generated code will be placed in the Gradle build directory.
 
 - With `--ts_proto_opt=initializeFieldsAsUndefined=false`, all optional field initializers will be omited from the generated base instances.
 
+- With `--ts_proto_opt=Mgoogle/protobuf/empty.proto=./google3/protobuf/empty`, ('M' means 'importMapping', similar to [protoc-gen-go](https://developers.google.com/protocol-buffers/docs/reference/go-generated#package)), the generated code import path for `./google/protobuf/empty.ts` will reflect the overridden value:
+
+  - `Mfoo/bar.proto=@myorg/some-lib` will map `foo/bar.proto` imports into `import ... from '@myorg/some-lib'`.
+  - `Mfoo/bar.proto=./some/local/lib` will map `foo/bar.proto` imports into `import ... from './some/local/lib'`.
+  - `Mfoo/bar.proto=some-modules/some-lib` will map `foo/bar.proto` imports into `import ... from 'some-module/some-lib'`.
+  - **Note**: Uses are accummulated, so multiple values are expected in the form of `--ts_proto_opt=M... --ts_proto_opt=M...` (one `ts_proto_opt` per mapping).
+  - **Note**: Proto files that match mapped imports **will not be generated**.
+
 ### NestJS Support
 
 We have a great way of working together with [nestjs](https://docs.nestjs.com/microservices/grpc). `ts-proto` generates `interfaces` and `decorators` for you controller, client. For more information see the [nestjs readme](NESTJS.markdown).

integration/codegen.ts

@@ -33,6 +33,9 @@ async function generate(binFile: string, baseDir: string, parameter: string) {
 
   for (let file of request.protoFile) {
     // Make a different utils per file to track per-file usage
+    if (options.M[file.name]) {
+      continue;
+    }
     const utils = makeUtils(options);
     const ctx: Context = { options, typeMap, utils };
     const [path, code] = generateFile(ctx, file);

integration/import-mapping/google/protobuf/timestamp.ts

@@ -0,0 +1,218 @@
+/* eslint-disable */
+import * as Long from "long";
+import * as _m0 from "protobufjs/minimal";
+
+export const protobufPackage = "google.protobuf";
+
+/**
+ * A Timestamp represents a point in time independent of any time zone or local
+ * calendar, encoded as a count of seconds and fractions of seconds at
+ * nanosecond resolution. The count is relative to an epoch at UTC midnight on
+ * January 1, 1970, in the proleptic Gregorian calendar which extends the
+ * Gregorian calendar backwards to year one.
+ *
+ * All minutes are 60 seconds long. Leap seconds are "smeared" so that no leap
+ * second table is needed for interpretation, using a [24-hour linear
+ * smear](https://developers.google.com/time/smear).
+ *
+ * The range is from 0001-01-01T00:00:00Z to 9999-12-31T23:59:59.999999999Z. By
+ * restricting to that range, we ensure that we can convert to and from [RFC
+ * 3339](https://www.ietf.org/rfc/rfc3339.txt) date strings.
+ *
+ * # Examples
+ *
+ * Example 1: Compute Timestamp from POSIX `time()`.
+ *
+ *     Timestamp timestamp;
+ *     timestamp.set_seconds(time(NULL));
+ *     timestamp.set_nanos(0);
+ *
+ * Example 2: Compute Timestamp from POSIX `gettimeofday()`.
+ *
+ *     struct timeval tv;
+ *     gettimeofday(&tv, NULL);
+ *
+ *     Timestamp timestamp;
+ *     timestamp.set_seconds(tv.tv_sec);
+ *     timestamp.set_nanos(tv.tv_usec * 1000);
+ *
+ * Example 3: Compute Timestamp from Win32 `GetSystemTimeAsFileTime()`.
+ *
+ *     FILETIME ft;
+ *     GetSystemTimeAsFileTime(&ft);
+ *     UINT64 ticks = (((UINT64)ft.dwHighDateTime) << 32) | ft.dwLowDateTime;
+ *
+ *     // A Windows tick is 100 nanoseconds. Windows epoch 1601-01-01T00:00:00Z
+ *     // is 11644473600 seconds before Unix epoch 1970-01-01T00:00:00Z.
+ *     Timestamp timestamp;
+ *     timestamp.set_seconds((INT64) ((ticks / 10000000) - 11644473600LL));
+ *     timestamp.set_nanos((INT32) ((ticks % 10000000) * 100));
+ *
+ * Example 4: Compute Timestamp from Java `System.currentTimeMillis()`.
+ *
+ *     long millis = System.currentTimeMillis();
+ *
+ *     Timestamp timestamp = Timestamp.newBuilder().setSeconds(millis / 1000)
+ *         .setNanos((int) ((millis % 1000) * 1000000)).build();
+ *
+ * Example 5: Compute Timestamp from Java `Instant.now()`.
+ *
+ *     Instant now = Instant.now();
+ *
+ *     Timestamp timestamp =
+ *         Timestamp.newBuilder().setSeconds(now.getEpochSecond())
+ *             .setNanos(now.getNano()).build();
+ *
+ * Example 6: Compute Timestamp from current time in Python.
+ *
+ *     timestamp = Timestamp()
+ *     timestamp.GetCurrentTime()
+ *
+ * # JSON Mapping
+ *
+ * In JSON format, the Timestamp type is encoded as a string in the
+ * [RFC 3339](https://www.ietf.org/rfc/rfc3339.txt) format. That is, the
+ * format is "{year}-{month}-{day}T{hour}:{min}:{sec}[.{frac_sec}]Z"
+ * where {year} is always expressed using four digits while {month}, {day},
+ * {hour}, {min}, and {sec} are zero-padded to two digits each. The fractional
+ * seconds, which can go up to 9 digits (i.e. up to 1 nanosecond resolution),
+ * are optional. The "Z" suffix indicates the timezone ("UTC"); the timezone
+ * is required. A proto3 JSON serializer should always use UTC (as indicated by
+ * "Z") when printing the Timestamp type and a proto3 JSON parser should be
+ * able to accept both UTC and other timezones (as indicated by an offset).
+ *
+ * For example, "2017-01-15T01:30:15.01Z" encodes 15.01 seconds past
+ * 01:30 UTC on January 15, 2017.
+ *
+ * In JavaScript, one can convert a Date object to this format using the
+ * standard
+ * [toISOString()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString)
+ * method. In Python, a standard `datetime.datetime` object can be converted
+ * to this format using
+ * [`strftime`](https://docs.python.org/2/library/time.html#time.strftime) with
+ * the time format spec '%Y-%m-%dT%H:%M:%S.%fZ'. Likewise, in Java, one can use
+ * the Joda Time's [`ISODateTimeFormat.dateTime()`](
+ * http://www.joda.org/joda-time/apidocs/org/joda/time/format/ISODateTimeFormat.html#dateTime%2D%2D
+ * ) to obtain a formatter capable of generating timestamps in this format.
+ */
+export interface Timestamp {
+  /**
+   * Represents seconds of UTC time since Unix epoch
+   * 1970-01-01T00:00:00Z. Must be from 0001-01-01T00:00:00Z to
+   * 9999-12-31T23:59:59Z inclusive.
+   */
+  seconds: number;
+  /**
+   * Non-negative fractions of a second at nanosecond resolution. Negative
+   * second values with fractions must still have non-negative nanos values
+   * that count forward in time. Must be from 0 to 999,999,999
+   * inclusive.
+   */
+  nanos: number;
+}
+
+function createBaseTimestamp(): Timestamp {
+  return { seconds: 0, nanos: 0 };
+}
+
+export const Timestamp = {
+  encode(message: Timestamp, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    if (message.seconds !== 0) {
+      writer.uint32(8).int64(message.seconds);
+    }
+    if (message.nanos !== 0) {
+      writer.uint32(16).int32(message.nanos);
+    }
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): Timestamp {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseTimestamp();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          message.seconds = longToNumber(reader.int64() as Long);
+          break;
+        case 2:
+          message.nanos = reader.int32();
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): Timestamp {
+    return {
+      seconds: isSet(object.seconds) ? Number(object.seconds) : 0,
+      nanos: isSet(object.nanos) ? Number(object.nanos) : 0,
+    };
+  },
+
+  toJSON(message: Timestamp): unknown {
+    const obj: any = {};
+    message.seconds !== undefined && (obj.seconds = Math.round(message.seconds));
+    message.nanos !== undefined && (obj.nanos = Math.round(message.nanos));
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<Timestamp>, I>>(object: I): Timestamp {
+    const message = createBaseTimestamp();
+    message.seconds = object.seconds ?? 0;
+    message.nanos = object.nanos ?? 0;
+    return message;
+  },
+};
+
+declare var self: any | undefined;
+declare var window: any | undefined;
+declare var global: any | undefined;
+var globalThis: any = (() => {
+  if (typeof globalThis !== "undefined") {
+    return globalThis;
+  }
+  if (typeof self !== "undefined") {
+    return self;
+  }
+  if (typeof window !== "undefined") {
+    return window;
+  }
+  if (typeof global !== "undefined") {
+    return global;
+  }
+  throw "Unable to locate global object";
+})();
+
+type Builtin = Date | Function | Uint8Array | string | number | boolean | undefined;
+
+export type DeepPartial<T> = T extends Builtin ? T
+  : T extends Array<infer U> ? Array<DeepPartial<U>> : T extends ReadonlyArray<infer U> ? ReadonlyArray<DeepPartial<U>>
+  : T extends {} ? { [K in keyof T]?: DeepPartial<T[K]> }
+  : Partial<T>;
+
+type KeysOfUnion<T> = T extends T ? keyof T : never;
+export type Exact<P, I extends P> = P extends Builtin ? P
+  : P & { [K in keyof P]: Exact<P[K], I[K]> } & { [K in Exclude<keyof I, KeysOfUnion<P>>]: never };
+
+function longToNumber(long: Long): number {
+  if (long.gt(Number.MAX_SAFE_INTEGER)) {
+    throw new globalThis.Error("Value is larger than Number.MAX_SAFE_INTEGER");
+  }
+  return long.toNumber();
+}
+
+// If you get a compile-error about 'Constructor<Long> and ... have no overlap',
+// add '--ts_proto_opt=esModuleInterop=true' as a flag when calling 'protoc'.
+if (_m0.util.Long !== Long) {
+  _m0.util.Long = Long as any;
+  _m0.configure();
+}
+
+function isSet(value: any): boolean {
+  return value !== null && value !== undefined;
+}

integration/import-mapping/import-mapping-test.ts

@@ -0,0 +1,43 @@
+import * as path from "node:path";
+import * as fs from "node:fs";
+import * as ts from "typescript";
+
+describe("import-mapping", () => {
+  it("generates imports correctly", () => {
+    const generatedPath = path.join(__dirname, "mapping.ts");
+    const generatedCode = fs.readFileSync(generatedPath, "utf8");
+    const source = ts.createSourceFile(generatedPath, generatedCode, ts.ScriptTarget.ES2018);
+
+    const actualImports = collectImports(source).map((imp) => imp.moduleSpecifier.getText(source).replace(/"/g, ""));
+    const expectedImports = [
+      "@google/protobuf/duration",
+      "@google/protobuf/empty",
+      "wkt/google/protobuf/struct",
+      "./google/protobuf/timestamp",
+      "protobufjs/minimal",
+      "@myorg/proto-npm-package",
+    ];
+    expect(actualImports.sort()).toEqual(expectedImports.sort());
+
+    expect(fs.existsSync(path.join("google", "protobuf", "duration.ts"))).toBeFalsy();
+    expect(fs.existsSync(path.join("google", "protobuf", "empty.ts"))).toBeFalsy();
+    expect(fs.existsSync(path.join("google", "protobuf", "struct.ts"))).toBeFalsy();
+    expect(fs.existsSync(path.join("some", "internal", "repo", "very_private.ts"))).toBeFalsy();
+  });
+});
+
+function collectImports(node: ts.Node) {
+  let nodes: ts.ImportDeclaration[] = [];
+  if (isImportDeclaration(node)) {
+    nodes.push(node);
+  } else {
+    node.forEachChild((node) => {
+      nodes = [...nodes, ...collectImports(node)];
+    });
+  }
+  return nodes;
+}
+
+function isImportDeclaration(node: ts.Node): node is ts.ImportDeclaration {
+  return node.kind === ts.SyntaxKind.ImportDeclaration;
+}

integration/import-mapping/mapping.proto

@@ -0,0 +1,29 @@
+syntax = "proto3";
+
+package import_mapping;
+
+import "google/protobuf/duration.proto"; // mapped to @google/...
+import "google/protobuf/empty.proto"; // mapped to @google/...
+import "google/protobuf/struct.proto"; // mapped to wkt/...
+import "google/protobuf/timestamp.proto"; // not mapped
+import "some/internal/repo/very_private.proto"; // mapped to @myorg/proto-npm-package
+
+message WithEmtpy {
+    google.protobuf.Empty empty = 1;
+}
+
+message WithStruct {
+    google.protobuf.Struct strut = 1;
+}
+
+message WithTimestamp {
+    google.protobuf.Timestamp timestamp = 1;
+}
+
+message WithAll {
+    google.protobuf.Empty empty = 1;
+    google.protobuf.Struct strut = 2;
+    google.protobuf.Timestamp timestamp = 3;
+    google.protobuf.Duration duration = 4;
+    myorg.protos.VeryVerySecret very_very_secret = 5;
+}