Cant load protobuf message with protobuf.js - node.js

Question

Im trying to use proto messages with protobuf.js, encode them and send them to a RabbitMQ message broker. I have the following sub-folders inside my project:
- model
- protos
- transactions.proto
- RabitMQ.js
- routes
- rmq-api.js
I added a route which does the following(Using express) in the rmq-api.js file:
const RabbitMQ = require('../model/RabbitMQ');
router.post('/api/transactions' ,function (req,res,next) {
RabbitMQ.PublishTransactionsMessage(DummyMessage).then(() => {
res.status(200).send({message: "OK :)"});
}).catch((e) => {
res.status(500).send({error:e.message});
});
});
In the RabitMQ.js file I have the following code:
module.exports = {
PublishTransactionsMessage: function(message) {
return new Promise((resolve, reject) => {
amqp.connect(RabbitMQConfig.url, function (error, connection) {
if (error) {
console.error("Could not connect to the rabbit message broker on {0} - " +
"Check connection please and try again".format(RabbitMQConfig.url));
console.error("Error message - {0}".format(error));
reject(error)
}
connection.createChannel(function(error, channel) {
if (error) {
console.error("Could Create channel - {0}".format(error.message));
reject(error)
}
const queue = RabbitMQConfig.queue;
channel.assertQueue(queue, {
durable: true
});
// Convert Message to protobuff
protobuf.load("./protos/transactions.proto").then((err, root) => {
if (err) {
reject(err);
}
let ScraperMessageResult = root.lookupType("transactions.ScraperMessageResult");
const errMsg = ScraperMessageResult.verify(message);
if (errMsg)
reject(errMsg);
let buffer = ScraperMessageResult.encode(message).finish();
channel.sendToQueue(queue, buffer);
console.log(`Sent ${message} to queue: ${queue}`);
resolve()
}).catch((err) => {
reject(err);
});
});
});
});
},
};
In the code shown above in the line:
protobuf.load("./protos/transactions.proto").then((err, root) => {
I keep catching the following error:
Inside this catch block:
}).catch((err) => {
reject(err);
});
This seems like a pretty simple problem however I havent found anything on this online so I might be missing something really simple here.
P.S. I tried using __dirname + "/protos/transaction.proto" and still couldnt get this to work.
Please help me figure this out.

Answer 1

The problem is that your function doesn't look at the dist directory,
await protocolBuffer.load(__dirname + '/item.proto'); should look there,
and also you need to copy the file manuly by using copy/cp command, you can add it as part of the package json script like so:
"build": "nest build && COPY src\\reading_list\\protocol_buffer\\*.proto dist\\reading_list\\protocol_buffer\\"