Merge pull request #3027 from zarinn3pal/error_details

Added error status details example

Author: murgatroid99

examples/error_details/README.md

@@ -0,0 +1,54 @@
+# Error Details
+
+This example demonstrates how to send and receive rich error details in gRPC using the standard `google.rpc` error model.
+
+## Overview
+
+The example uses the `@q42philips/node-grpc-error-details` package to:
+- **Server**: Serialize error details (like `BadRequest`) into the `grpc-status-details-bin` metadata
+- **Client**: Deserialize error details from the metadata
+
+This follows the official gRPC error model specification.
+
+## Start the server
+
+Run the server, which sends a rich error if the name field is empty:
+
+```bash
+node server.js
+```
+
+## Run the client
+
+In another terminal, run the client which makes two calls:
+1. A successful call with a valid name
+2. A failing call with an empty name that receives rich error details
+
+```bash
+node client.js
+```
+
+## Expected Output
+
+The client makes two calls and displays both results:
+
+**Successful call:**
+```
+Greeting: Hello World
+```
+
+**Failed call with standard error and rich error details:**
+```
+--- Standard gRPC Error Received ---
+Code: 3
+Status: INVALID_ARGUMENT
+Message: Simple Error: The name field was empty.
+
+--- Rich Error Details---
+Violation: [
+  {
+    "field": "name",
+    "description": "Name field is required"
+  }
+]
+```

examples/error_details/client.js

@@ -0,0 +1,79 @@
+/*
+ *
+ * Copyright 2025 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+var PROTO_PATH = __dirname + '/../protos/helloworld.proto';
+
+var grpc = require('@grpc/grpc-js');
+var protoLoader = require('@grpc/proto-loader');
+var packageDefinition = protoLoader.loadSync(
+  PROTO_PATH,
+  {
+    keepCase: true,
+    longs: String,
+    enums: String,
+    defaults: true,
+    oneofs: true
+  });
+var hello_proto = grpc.loadPackageDefinition(packageDefinition).helloworld;
+
+var {deserializeGoogleGrpcStatusDetails, BadRequest} =
+  require('@q42philips/node-grpc-error-details');
+
+var client = new hello_proto.Greeter('localhost:50051', grpc.credentials.createInsecure());
+
+function main() {
+  // Successful call
+  client.sayHello({name: 'World'}, function (err, response) {
+    if (err) {
+      console.error('Successful call failed:', err.message);
+      return;
+    }
+    console.log('Greeting:', response.message);
+
+    // Failing call with empty name
+    client.sayHello({name: ''}, function (err, response) {
+      if (err) {
+        console.log('\n--- Standard gRPC Error Received ---');
+        console.log('Code:', err.code);
+        console.log('Status:', grpc.status[err.code] || 'UNKNOWN');
+        console.log('Message:', err.details);
+
+        // Deserialize rich error details
+        var grpcErrorDetails = deserializeGoogleGrpcStatusDetails(err);
+        if (grpcErrorDetails) {
+          console.log('\n--- Rich Error Details---');
+          grpcErrorDetails.details.forEach(function(detail) {
+            if (detail instanceof BadRequest) {
+              var violations = detail.getFieldViolationsList().map(function(violation) {
+                return {
+                  field: violation.getField(),
+                  description: violation.getDescription()
+                };
+              });
+              console.log('Violation:', JSON.stringify(violations, null, 2));
+            }
+          });
+        }
+      } else {
+        console.log('Expected error but got success:', response.message);
+      }
+    });
+  });
+}
+
+main();

examples/error_details/server.js

@@ -0,0 +1,86 @@
+/*
+ *
+ * Copyright 2025 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+var PROTO_PATH = __dirname + '/../protos/helloworld.proto';
+
+var grpc = require('@grpc/grpc-js');
+var protoLoader = require('@grpc/proto-loader');
+var packageDefinition = protoLoader.loadSync(
+  PROTO_PATH,
+  {
+    keepCase: true,
+    longs: String,
+    enums: String,
+    defaults: true,
+    oneofs: true
+  });
+var hello_proto = grpc.loadPackageDefinition(packageDefinition).helloworld;
+
+var {Status, BadRequest} = require('@q42philips/node-grpc-error-details');
+var {Any} = require('google-protobuf/google/protobuf/any_pb');
+
+/**
+ * Implements the SayHello RPC method.
+ */
+function sayHello(call, callback) {
+  if (call.request.name === '') {
+    // Create BadRequest detail
+    var fieldViolation = new BadRequest.FieldViolation();
+    fieldViolation.setField('name');
+    fieldViolation.setDescription('Name field is required');
+
+    var badRequest = new BadRequest();
+    badRequest.setFieldViolationsList([fieldViolation]);
+
+    // Pack into Any
+    var anyMessage = new Any();
+    anyMessage.pack(badRequest.serializeBinary(), 'google.rpc.BadRequest');
+
+    // Create Status
+    var status = new Status();
+    status.setCode(3); // INVALID_ARGUMENT
+    status.setMessage('Request argument invalid');
+    status.setDetailsList([anyMessage]);
+
+    // Attach as metadata
+    var metadata = new grpc.Metadata();
+    metadata.add('grpc-status-details-bin', Buffer.from(status.serializeBinary()));
+
+    callback({
+      code: grpc.status.INVALID_ARGUMENT,
+      details: 'Simple Error: The name field was empty.',
+      metadata: metadata
+    });
+    return;
+  }
+
+  callback(null, {message: 'Hello ' + call.request.name});
+}
+
+/**
+ * Starts an RPC server.
+ */
+function main() {
+  var server = new grpc.Server();
+  server.addService(hello_proto.Greeter.service, {sayHello: sayHello});
+  server.bindAsync('0.0.0.0:50051', grpc.ServerCredentials.createInsecure(), () => {
+    console.log('Server running at http://0.0.0.0:50051');
+  });
+}
+
+main();

examples/package.json

@@ -8,6 +8,7 @@
     "@grpc/grpc-js": "^1.10.2",
     "@grpc/grpc-js-xds": "^1.10.0",
     "@grpc/reflection": "^1.0.0",
+    "@q42philips/node-grpc-error-details": "^2.1.0",
     "lodash": "^4.6.1",
     "minimist": "^1.2.0"
   }