client.js

/*
 *
 * Copyright 2015 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 path = require('path');
const grpc = require('@grpc/grpc-js');
const protoLoader = require('@grpc/proto-loader');
const pino = require('pino');

const PROTO_PATH = path.join(__dirname, './proto/demo.proto');
const PORT = 7000;

function _loadProto(path) {
  const packageDefinition = protoLoader.loadSync(path, {
    keepCase: true,
    longs: String,
    enums: String,
    defaults: true,
    oneofs: true,
  });
  return grpc.loadPackageDefinition(packageDefinition);
}

const MAIN_PROTO_PATH = path.join(__dirname, './proto/demo.proto');

const shopProto = _loadProto(MAIN_PROTO_PATH).hipstershop;

const client = new shopProto.CurrencyService(
  `0.0.0.0:${PORT}`,
  grpc.credentials.createInsecure()
);

const logger = pino({
  name: 'currencyservice-client',
  messageKey: 'message',
});

const request = {
  from: {
    currency_code: 'CHF',
    units: 300,
    nanos: 0,
  },
  to_code: 'EUR',
};

function _moneyToString(m) {
  return `${m.units}.${m.nanos.toString().padStart(9, '0')} ${m.currency_code}`;
}

client.getSupportedCurrencies({}, (err, response) => {
  if (err) {
    logger.error(`Error in getSupportedCurrencies: ${err}`);
  } else {
    logger.info(`Currency codes: ${response.currency_codes}`);
  }
});

client.convert(request, (err, response) => {
  if (err) {
    logger.error(`Error in convert: ${err}`);
  } else {
    logger.info(
      `Convert: ${_moneyToString(request.from)} to ${_moneyToString(response)}`
    );
  }
});