(wip): GRPC exception and mapping

integration/microservices/e2e/sum-grpc.spec.ts

@@ -104,7 +104,17 @@ describe('GRPC transport', () => {
     });
   });
 
-  after(async () => {
+  it(`handle exception correctly`, () => {
+    return (
+      request(server)
+        .post('/divide')
+        .send({ first: 42, last: 0 })
+        // TODO: this will change once the grpc client raise the closest HTTP exception to OutOfBound
+        .expect(500, { message: 'Dividing by 0 is Strictly Forbidden' })
+    );
+  });
+
+  afterEach(async () => {
     await app.close();
     client.close();
   });

integration/microservices/src/grpc/grpc.controller.ts

@@ -1,15 +1,21 @@
-import { Body, Controller, HttpCode, Post } from '@nestjs/common';
+import { Body, Controller, HttpCode, Post, UseFilters } from '@nestjs/common';
 import {
   Client,
   ClientGrpc,
   GrpcMethod,
   GrpcStreamCall,
   GrpcStreamMethod,
   Transport,
+  GrpcOutOfRangeException,
 } from '@nestjs/microservices';
 import { join } from 'path';
 import { Observable, of } from 'rxjs';
 
+interface DivideParams {
+  first: number;
+  last: number;
+}
+
 @Controller()
 export class GrpcController {
   @Client({
@@ -23,7 +29,7 @@ export class GrpcController {
 
   @Post()
   @HttpCode(200)
-  call(@Body() data: number[]): Observable<number> {
+  sumHttp(@Body() data: number[]): Observable<number> {
     const svc = this.client.getService<any>('Math');
     return svc.sum({ data });
   }
@@ -57,4 +63,20 @@ export class GrpcController {
       stream.write({ result: msg.data.reduce((a, b) => a + b) });
     });
   }
+
+  @Post('/divide')
+  @HttpCode(200)
+  divideHttp(@Body() { first, last }: DivideParams): Observable<number> {
+    const svc = this.client.getService<any>('Math');
+    return svc.sum({ first, last });
+  }
+
+  @GrpcMethod('Math')
+  async divide({ first, last }: DivideParams): Promise<any> {
+    const result = first / last;
+    if (!isFinite(result)) {
+      throw new GrpcOutOfRangeException('Dividing by 0 is Strictly Forbidden');
+    }
+    return result;
+  }
 }

integration/microservices/src/grpc/math.proto

@@ -3,15 +3,19 @@ syntax = "proto3";
 package math;
 
 service Math {
-  rpc Sum (RequestSum) returns (SumResult);
-  rpc SumStream(stream RequestSum) returns(stream SumResult);
-  rpc SumStreamPass(stream RequestSum) returns(stream SumResult);
+  rpc Sum(RequestSum) returns (SumResult);
+  rpc SumStream(stream RequestSum) returns (stream SumResult);
+  rpc SumStreamPass(stream RequestSum) returns (stream SumResult);
+  rpc Divide(RequestDivide) returns (DivideResult) {}
 }
 
-message SumResult {
-  int32 result = 1;
-}
+message SumResult { int32 result = 1; }
+
+message RequestSum { repeated int32 data = 1; }
+
+message DivideResult { int32 result = 1; }
 
-message RequestSum {
-  repeated int32 data = 1;
+message RequestDivide {
+  int32 first = 1;
+  int32 last = 2;
 }