-
Notifications
You must be signed in to change notification settings - Fork 636
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge pull request #2585 from murgatroid99/example_error_handling
Add error handling example
- Loading branch information
Showing
3 changed files
with
180 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,23 @@ | ||
# Error Handling | ||
|
||
This example demonstrates basic RPC error handling in gRPC for unary and | ||
streaming response cardinalities. | ||
|
||
## Start the server | ||
|
||
Run the server, whcih returns an error if the RPC request's `name` field is | ||
empty. | ||
|
||
``` | ||
node server.js | ||
``` | ||
|
||
## Run the client | ||
|
||
Then run the client in another terminal, which makes two requests for each of | ||
unary and streaming responses: one with an empty Name field and one with it | ||
populated with the current username provided by os/user. | ||
|
||
``` | ||
node client.js | ||
``` |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,89 @@ | ||
/* | ||
* | ||
* Copyright 2023 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. | ||
* | ||
*/ | ||
|
||
const grpc = require('@grpc/grpc-js'); | ||
const protoLoader = require('@grpc/proto-loader'); | ||
const parseArgs = require('minimist'); | ||
const os = require('os'); | ||
|
||
const PROTO_PATH = __dirname + '/../protos/helloworld.proto'; | ||
|
||
const packageDefinition = protoLoader.loadSync( | ||
PROTO_PATH, | ||
{keepCase: true, | ||
longs: String, | ||
enums: String, | ||
defaults: true, | ||
oneofs: true | ||
}); | ||
const helloProto = grpc.loadPackageDefinition(packageDefinition).helloworld; | ||
|
||
function unaryCall(client, requestId, name, expectedCode) { | ||
console.log(`[${requestId}] Calling SayHello with name:"${name}"`); | ||
return new Promise((resolve, reject) => { | ||
client.sayHello({name: name}, (error, value) => { | ||
if (error) { | ||
if (error.code === expectedCode) { | ||
console.log(`[${requestId}] Received error ${error.message}`); | ||
} else { | ||
console.log(`[${requestId}] Received unexpected error ${error.message}`); | ||
} | ||
} | ||
if (value) { | ||
console.log(`[${requestId}] Received response ${value.message}`); | ||
} | ||
resolve(); | ||
}); | ||
}); | ||
} | ||
|
||
function streamingCall(client, requestId, name, expectedCode) { | ||
console.log(`[${requestId}] Calling SayHelloStreamReply with name:"${name}"`); | ||
return new Promise((resolve, reject) => { | ||
const call = client.sayHelloStreamReply({name: name}); | ||
call.on('data', value => { | ||
console.log(`[${requestId}] Received response ${value.message}`); | ||
}); | ||
call.on('status', status => { | ||
console.log(`[${requestId}] Received status with code=${grpc.status[status.code]} details=${status.details}`); | ||
resolve(); | ||
}); | ||
call.on('error', error => { | ||
if (error.code === expectedCode) { | ||
console.log(`[${requestId}] Received expected error ${error.message}`); | ||
} else { | ||
console.log(`[${requestId}] Received unexpected error ${error.message}`); | ||
} | ||
}); | ||
}); | ||
} | ||
|
||
async function main() { | ||
let argv = parseArgs(process.argv.slice(2), { | ||
string: 'target', | ||
default: {target: 'localhost:50052'} | ||
}); | ||
const client = new helloProto.Greeter(argv.target, grpc.credentials.createInsecure()); | ||
const name = os.userInfo().username ?? 'unknown'; | ||
await unaryCall(client, 1, '', grpc.status.INVALID_ARGUMENT); | ||
await unaryCall(client, 2, name, grpc.status.OK); | ||
await streamingCall(client, 3, '', grpc.status.INVALID_ARGUMENT); | ||
await streamingCall(client, 4, name, grpc.status.OK); | ||
} | ||
|
||
main(); |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,68 @@ | ||
/* | ||
* | ||
* Copyright 2023 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; | ||
|
||
/** | ||
* Implements the SayHello RPC method. | ||
*/ | ||
function sayHello(call, callback) { | ||
if (call.request.name === '') { | ||
callback({code: grpc.status.INVALID_ARGUMENT, details: 'request missing required field: name'}); | ||
} | ||
callback(null, {message: 'Hello ' + call.request.name}); | ||
} | ||
|
||
const REPLY_COUNT = 5; | ||
|
||
function sayHelloStreamReply(call) { | ||
if (call.request.name === '') { | ||
call.emit('error', {code: grpc.status.INVALID_ARGUMENT, details: 'request missing required field: name'}); | ||
} else { | ||
for (let i = 0; i < REPLY_COUNT; i++) { | ||
call.write({message: 'Hello ' + call.request.name}); | ||
} | ||
call.end(); | ||
} | ||
} | ||
|
||
/** | ||
* Starts an RPC server that receives requests for the Greeter service at the | ||
* sample server port | ||
*/ | ||
function main() { | ||
var server = new grpc.Server(); | ||
server.addService(hello_proto.Greeter.service, {sayHello: sayHello, sayHelloStreamReply: sayHelloStreamReply}); | ||
server.bindAsync('0.0.0.0:50052', grpc.ServerCredentials.createInsecure(), () => { | ||
server.start(); | ||
}); | ||
} | ||
|
||
main(); |