calling a method inside async callback - methods

I am using kafka in my project using kafka-node package...
I have introduced a method and inside it i am trying to use a kafka module for eg:
Meteor.methods
kafka: (topic, message) ->
if(Meteor.isServer)
message = JSON.stringify(message)
kafka = Meteor.npmRequire 'kafka-node'
HighLevelProducer = kafka.HighLevelProducer
Client = kafka.Client
client = new Client
producer = new HighLevelProducer(client)
payloads =[{topic: topic, messages: [message]}]
producer.on 'ready', ->
producer.send payloads, (error,data) ->
if not error
HighLevelConsumer = kafka.HighLevelConsumer
Client = kafka.Client
client = new Client('localhost:2181')
topics = [ { topic: topic } ]
options =
autoCommit: true
fetchMaxWaitMs: 1000
fetchMaxBytes: 1024 * 1024
consumer = new HighLevelConsumer(client, topics, options)
consumer.on 'message',(message) ->
console.log message.value
#Meteor.call 'saveMessage', message.value, (error,data) ->
return
consumer.on 'error', (err) ->
console.log 'error', err
return
producer.on 'error', (err) ->
console.log 'error', err
Everything was fine until i decided to use meteor.call and call a method to save that message..
It gives me this error.
Meteor code must always run within a Fiber. Try wrapping callbacks
that you pass to non-Meteor libraries with Meteor.bindEnvironment
I tried encapsulating it inside Fiber, used Meteor.wrapAsync(), Neither helped,
Please guys can you help me, i am having difficult time solving this issue...

If you're using node style callbacks, you can use Meteor.bindEnvironment around the callback. For example:
let Sockets = new Mongo.Collection('connections');
function createConnection (name) {
check(name, String);
let socket = net.connect(23, '192.168.1.3', Meteor.bindEnvironment(function () {
Sockets.upsert({ name: name }, { $set: { status: 'connected' } });
}));
}

Related

ThrottlerGuard not working on Websocket in Nestjs

I'm creating an application that is using Nestjs with websockets, but now I need to add rate limit on the sockets, but analyzing the documentation documentation link and implementing what it says in it, when I use #UseGuards(MyGuard) an error occurs in the application.
My Guard:
#Injectable()
export class NewThrottlerGuard extends ThrottlerGuard {
protected async handleRequest(
context: ExecutionContext,
limit: number,
ttl: number,
): Promise<boolean> {
console.log('Request');
const client = context.switchToWs().getClient();
const ip = client.conn.remoteAddress;
const key = this.generateKey(context, ip);
const ttls = await this.storageService.getRecord(key);
if (ttls.length >= limit) {
throw new ThrottlerException();
}
await this.storageService.addRecord(key, ttl);
return true;
}
}
Websocket:
#UseGuards(NewThrottlerGuard)
#SubscribeMessage('sendMessage')
sendMessage(
#ConnectedSocket() client: Socket,
#MessageBody() message: string,
) {
client.rooms.forEach((room) => {
if (room !== client.id) {
client.broadcast.to(room).emit('message', message);
}
});
}
Error in console:
/node_modules/#nestjs/common/utils/validate-each.util.js:22
throw new InvalidDecoratorItemException(decorator, item, context.name);
^
Error: Invalid guard passed to #UseGuards() decorator (ChatGateway).
at validateEach
The file in: #nestjs/common/utils/validate-each.util.js:22
function validateEach(context, arr, predicate, decorator, item) {
if (!context || !context.name) {
return true;
}
console.log(context, arr)
const errors = arr.some(str => !predicate(str));
if (errors) {
throw new InvalidDecoratorItemException(decorator, item, context.name);
}
return true;
}
i put some console.log then in the terminal it show:
[Function: ChatGateway] [ undefined ]
In Github Throttler documentation they say: You cannot bind the guard with APP_GUARD or app.useGlobalGuards() due to how Nest binds global guards.
So, im using #UseGuards()
The guard itself was written correctly, but it was put in a location that importing it made a circular reference between files, so when #UseGuards() was used it became #UseGuards(undefined) which caused the cryptic error message. Moving the guard to a dedicated file will fix the error
I follow your github reference settings and it doesn't work,The following is my code, where is my setting wrong, and the request to ws is not intercepted(In the handleRequest method)

How do you use a nodejs Lambda in AWS as a producer to send messages to MSK topic without creating EC2 client server?

I am trying to create a Lambda in AWS that serves as a producer to an MSK topic. All the AWS docs say to create a new EC2 instance, but as my Lambda is in the same VPC I feel like this should work. I am very new to this and I notice my log statement never hits in my producer.on function.
I am using nodejs and the kafka-node module. The code can be found below.
Essentially, I am just wondering if anyone knows how to do this and why the producer.on function is never hit when I run test through the Lambda? This is just some test code to see if I can get it to send, but if any more data is needed oy help please let me know and thanks in advance.
exports.handler = async (event, context,callback) => {
const kafka = require('kafka-node');
const bp = require('body-parser');
const kafka_topic = 'MyTopic';
const Producer = kafka.Producer;
var KeyedMessage = kafka.KeyedMessage;
const Client = kafka.Client;
const client = new kafka.KafkaClient({kafkaHost: 'myhost:9094'});
console.log('client :: '+JSON.stringify(client));
const producer = new Producer(client);
console.log('about to hit producer code');
producer.on('ready', function() {
console.log('Hello there!')
let message = 'my message';
let keyedMessage = new KeyedMessage('keyed', 'me keyed message');
producer.send([
{ topic: kafka_topic, partition: 0, messages: [message, keyedMessage], attributes: 0 }
], function (err, result) {
console.log(err || result);
process.exit();
});
});
producer.on('error', function (err) {
console.log('error', err);
});
}
return "success";
What you need is to be able to produce messages on your MSK cluster using REST API. Why not setup a REST proxy for MSK as detailed here and then call this API to produce your messages to MSK.

Add identifier to websocket

I am using the Node.js ws library, to listen to events in user accounts on a 3rd party API. For each user, I open a websocket to listen to the events in the user's account.
Turns out, the 3rd-party API doesn't provide a userID for each event, so if I have 10 websocket connections to user-accounts, I cannot determine which account an event came from.
I have access to a unique userId prior to starting each of my connections.
Is there a way to append or wrap the websocket connection with the userId identifier, to each connection I make, such that when I receive an event, I can access the custom identifier, and subsequently know which user's account the event came from?
The code below is a mix of real code, and pseudocode (i.e customSocket)
const ws = new WebSocket('wss://thirdparty-api.com/accounts', {
port: 8080,
});
ws.send(
JSON.stringify({
action: 'authenticate',
data: {
oauth_token: access_token,
},
})
);
// wrap and attach data here (pseudocode at top-level)
customSocket.add({userId,
ws.send(
JSON.stringify({
action: 'listen',
data: {
streams: ['action_updates'],
},
})
)
})
// listen for wrapper data here, pseudocode at top level
customSocket.emit((customData) {
ws.on('message', function incoming(data) {
console.log('incoming -> data', data.toString());
})
console.log('emit -> customData', customData);
})
Looking at the socket.io library, the namespace feature may solve for this, but I can't determine if that's true or not. Below is an example in their documentation:
// your application has multiple tenants so you want to dynamically create one namespace per tenant
const workspaces = io.of(/^\/\w+$/);
workspaces.on('connection', socket => {
const workspace = socket.nsp;
workspace.emit('hello');
});
// this middleware will be assigned to each namespace
workspaces.use((socket, next) => {
// ensure the user has access to the workspace
next();
});
I found a solution to this which is fairly simple. First create a message handler function:
const eventHandler = (uid, msg) => {
console.log(`${uid} did ${msg}`);
};
Then, when you create the websocket for the given user, wrap the .on event with the handler:
const createSocketForUser = (uid, eventHandler) => {
const socket = new WebSocket(/* ... */);
socket.onmessage = (msg) => {
eventHandler(uid, msg)
};
return socket;
}

How to set up a socket connection on a strapi server

I am trying to integrate socket.io with strapi. But unfortunately I have been unable to do so without any proper tutorial or documentation covering this aspect.
I followed along with the only resource I found online which is:
https://medium.com/strapi/strapi-socket-io-a9c856e915a6
But I think the article is outdated. I can't seem to run the code mentioned in it without running into tonnes of errors.
Below is my attempt to implement it and I have been trying to connect it through a chrome websocket plugin smart websocket client But I am not getting any response when I try to run the server.
I'm totally in the dark. Any help will be appreciated
module.exports = ()=> {
// import socket io
var io = require('socket.io')(strapi.server)
console.log(strapi.server) //undefined
// listen for user connection
io.on('connect', socket => {
socket.send('Hello!');
console.log("idit")
// or with emit() and custom event names
socket.emit('greetings', 'Hey!', { 'ms': 'jane' }, Buffer.from([4, 3, 3, 1]));
// handle the event sent with socket.send()
socket.on('message', (data) => {
console.log(data);
});
// handle the event sent with socket.emit()
socket.on('salutations', (elem1, elem2, elem3) => {
console.log(elem1, elem2, elem3);
});
});
};
So I found the solution. Yay. I'll put it here just in case anybody needs it.
boostrap.js
module.exports = async () => {
process.nextTick(() =>{
var io = require('socket.io')(strapi.server);
io.on('connection', async function(socket) {
console.log(`a user connected`)
// send message on user connection
socket.emit('hello', JSON.stringify({message: await strapi.services.profile.update({"posted_by"})}));
// listen for user diconnect
socket.on('disconnect', () =>{
console.log('a user disconnected')
});
});
strapi.io = io; // register socket io inside strapi main object to use it globally anywhere
})
};
Found this at: https://github.com/strapi/strapi/issues/5869#issuecomment-619508153_
Apparently, socket.server is not available when the server starts. So you have to make use of process.nextTick that waits for the socket.server to initialize.
I'll also add a few questions that I faced when setting this up.
How do i connect from an external client like nuxt,vue or react?
You just have to connect through "http://localhost:1337" that is my usual address for strapi.
I am using nuxt as my client side and this is how set up my socketio on the client side
I first installed nuxt-socket-io through npm
Edited the nuxt.config file as per it's documention
modules:[
...
'nuxt-socket-io',
...
],
io: {
// module options
sockets: [
{
name: 'main',
url: 'http://localhost:1337',
},
],
},
And then i finally added a listener in one of my pages.
created() {
this.socket = this.$nuxtSocket({})
this.socket.on('hello', (msg, cb) => {
console.log('SOCKET HI')
console.log(msg)
})
},
And it works.
A clean way to integrate third-party services into Strapi is to use hooks. They are loaded once during the server boot. In this case, we will create a local hook.
The following example has worked with strapi#3.6.
Create a hook for socket.io at ./hooks/socket.io/index.js
module.exports = strapi => {
return {
async initialize() {
const ioServer = require('socket.io')(strapi.server, {
cors: {
origin: process.env['FRONT_APP_URL'],
methods: ['GET', 'POST'],
/* ...other cors options */
}
})
ioServer.on('connection', function(socket) {
socket.emit('hello', `Welcome ${socket.id}`)
})
/* HANDLE CLIENT SOCKET LOGIC HERE */
// store the server.io instance to global var to use elsewhere
strapi.services.ioServer = ioServer
},
}
}
Enable the new hook in order for Strapi to load it - ./config/hook.js
module.exports = {
settings: {
'socket.io': {
enabled: true,
},
},
};
That's done. You can access the websocket server inside ./config/functions/bootstrap.js or models' lifecycle hooks.
// ./api/employee/models/employee.js
module.exports = {
lifecycles: {
async afterUpdate(result, params, data) {
strapi.services.ioServer.emit('update:employee', result)
},
},
};
For those who are looking the answer using Strapi version 4
var io = require("socket.io")(strapi.server.httpServer)

Issue Broadcasting to Socket.io Rooms of A Namespace

I'm trying to set up a server that can dynamically create many rooms for many namespaces. I'm currently just trying to broadcast to sockets of a room, when a new socket has joined that room.
So far I have been able to broadcast to a specific namespace and my event listeners on the client receives the message. However when I try to broadcast to a room, of a specific namespace, my event listener doesn't receive that message.
I've turned on the Debugger mode and see the socket.io-client:socket emitting the event with the right payload and event type. So I am not sure what I am missing since the documentation also seems fairly straightforward. Any help would be much appreciated. Below is my code.
Server
const colorNs = io.of('/color');
colorNs.on('connection', (socket) => {
const { id } = socket.handshake.query;
const { id:connId } = socket.conn;
if(id) {
socket.join(id);
socket.broadcast.to(id).emit('user:connect', { id: connId });
}
socket.on('disconnect', () => {
const { id } = socket.handshake.query;
const { id:connId } = socket.conn;
socket.broadcast.to(id).emit('user:disconnect', { id: connId });
});
});
Client
const socket = io('/color?id="123"');
socket.on('user:connect', () => console.log('data', data));
Client - Debug Trace
socket.io-parser decoded 2/color,["user:connect",{"id":"IZTTPidF121JCzf9AAAO"}] as {"type":2,"nsp":"/color","data":["user:connect",{"id":"IZTTPidF121JCzf9AAAO"}]} +1ms
browser.js:133
socket.io-client:socket emitting event ["user:connect",{"id":"IZTTPidF121JCzf9AAAO"}] +3ms

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