Messaging API not using http.Agent (proxy)

[eheikkinen]

Describe your environment

Operating System version: Windows 10
Firebase SDK version: 8.8.0
Firebase Product: Messaging
Node.js version: v10.15.1
NPM version: 6.4.1

Describe the problem

When using the Messaging API the request do not utilize the setted http.Agent when application was initialized. This results in the requests to fail if sending behind a proxy with the following error:

Error while making request: getaddrinfo ENOTFOUND fcm.googleapis.com fcm.googleapis.com:443. Error code: ENOTFOUND

The authentication does work as it is using the http.Agent properly when passed to:

var firebaseadmin = require("firebase-admin");
firebaseadmin.initializeApp({
    credential: firebaseadmin.credential.cert(accountKey, new HttpsProxyAgent(process.env.http_proxy))
});

Steps to reproduce:

You have to be making request through a proxy server.

Ugly fix

Ugly fix is to modify messaging-api-request.js

var HttpsProxyAgent = require('https-proxy-agent');

and then adding httpAgent to all the requests, e.g.:

FirebaseMessagingRequestHandler.prototype.invokeRequestHandler = function (host, path, requestData) {
    var request = {
        method: FIREBASE_MESSAGING_HTTP_METHOD,
        url: "https://" + host + path,
        data: requestData,
        headers: LEGACY_FIREBASE_MESSAGING_HEADERS,
        timeout: FIREBASE_MESSAGING_TIMEOUT,
        httpAgent: new HttpsProxyAgent(process.env.http_proxy)
    };
    ...
}

[hiranya911]

AuthorizedHttpClient automatically adds the httpAgent to all requests:

firebase-admin-node/src/utils/api-request.ts

Lines 819 to 821 in 45905e4

	if (!requestCopy.httpAgent && this.app.options.httpAgent) {
	requestCopy.httpAgent = this.app.options.httpAgent;
	}

Here's the corresponding test case:

firebase-admin-node/test/unit/utils/api-request.spec.ts

Lines 1261 to 1280 in 45905e4

	it('should use the HTTP agent set in AppOptions', () => {
	const respData = {success: true};
	const scope = nock('https://' + mockHost, requestHeaders)
	.get(mockPath)
	.reply(200, respData, {
	'content-type': 'application/json',
	});
	mockedRequests.push(scope);
	const client = new AuthorizedHttpClient(mockAppWithAgent);
	return client.send({
	method: 'GET',
	url: mockUrl,
	}).then((resp) => {
	expect(resp.status).to.equal(200);
	expect(transportSpy!.callCount).to.equal(1);
	const options = transportSpy!.args[0][0];
	expect(options.agent).to.equal(agentForApp);
	});
	});
	});

[hiranya911]

Problem here is you don't have an httpAgent specified in AppOptions. You're only specifying it for the credential, which is not enough.

[eheikkinen]

Thank you hiranya911. You are correct. It is working when the httpAgent was also set in the AppOptions.