I have a custom service that must return data in CSV format.
I can't use a standard Express route, because I need Feathers' hooks on this endpoint.
I couldn't find an example of a Feathers service returning non-HTML, non-JSON data, and have found no way to specify a response content type.
Using res.set('Content-Type', 'text/csv') before returning from the service method didn't work; the final Content-Type header was reset to application/json, even though the method's return value was a regular string.
How can I properly set arbitrary response content types in Feathers' custom service methods?
You can customize the response format like this:
const feathers = require('feathers');
const rest = require('feathers-rest');
const app = feathers();
function restFormatter(req, res) {
res.format({
'text/plain': function() {
res.end(`The Message is: "${res.data.text}"`);
}
});
}
app.configure(rest(restFormatter));
The complete documentation can be found here.
Using your own service specific middleware to send the response should also work.
Related
I have to create a webhook from typeform to firebase. I will create a cloud function listening to events sent from typeform. The typeform is managed by a third party.
The only issue I have, is the authorization part for the webhook. I understood (from reading different post) that anyone can "talk" to the cloud function URL. But I would like to have a secure and exclusive communication between typeform and firebase.
Any hints ?
Thank for your time.
You can definitively connect a Typeform webhook to a Cloud function and push data to Firebase storage.
In addition to authentication pointed by Frank, Typeform also provides a signature mechanism to ensure that the request comes from Typeform webhook.
Typeform lets you define a secret to sign the webhook payload.
When you receive the payload on your end, in the cloud function, you verify first if it's signed correctly, if it's not it means it's not coming from Typeform, therefore, you should not deal with it.
Here is an example to verify the webhook signature:
app.post('/typeform/webhook', async (request, response) => {
console.log('~> webhook received');
// security check, let's make sure request comes from typeform
const signature = request.headers['typeform-signature']
const isValid = verifySignature(signature, request.body.toString())
if (!isValid) {
throw new Error('Webhook signature is not valid, someone is faking this!');
}
//valid signature let's do something with data received
})
And here is the verifySignature function
const crypto = require('crypto')
const verifySignature = function(receivedSignature, payload){
const hash = crypto
.createHmac('sha256', webhookSecret)
.update(payload)
.digest('base64')
return receivedSignature === `sha256=${hash}`
}
There are more details on Typeform documentation.
Hope it helps :)
Calling request.body.toString() does not work the way it is described in #Nicolas Greniés answer. The result will always be the string "[Object object]", as it only utilizes the default prototype as described here (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/toString).
A valid approach to stringify req.body would be to use JSON.stringify() which would still not deliver the expected result as you need to hash the original binary data (https://developer.typeform.com/webhooks/secure-your-webhooks/).
The Solution (without Firebase)
Use app.use(bodyParser.raw({ type: 'application/json' })) as specified here (Validate TypeForm Webhook payload in Node) to get the raw binary data and pass the request body directly into the hashing function.
const bodyParser = require("body-parser");
app.use(bodyParser.raw({ type: "application/json" })); // Notice .raw !
app.post("/typeform-handler", (req, res) => {
const hash = crypto
.createHmac('sha256', MY_TYPEFORM_SECRET)
.update(req.body) // Pass the raw body after getting it using bodyParser
.digest('base64')
})
The solution using Firebase
If you are using a Firebase Cloud Function to handle the request, you can't use bodyParser this way as Firebase already takes care of the parsing (https://firebase.google.com/docs/functions/http-events#read_values_from_the_request). Instead, use req.rawBody to access the raw body and pass it to the hash function.
// No need for bodyParser
app.post("/typeform-handler", (req, res) => {
const hash = crypto
.createHmac('sha256', MY_TYPEFORM_SECRET)
.update(req.rawBody) // Notice .rawBody instead of just .body
.digest('base64')
})
Remark for TypeScript users
The default Express Request object does not contain a rawBody property. Be aware that TypeScript therefore might throw an error of no overload matches this call or Property 'rawBody' does not exist on type 'Request<ParamsDictionary, any, any, ParsedQs, Record<string, any>>'. The actual Request object will however be provided by Firebase and will contain said properties. You can access the actual Request object type using functions.https.Request.
I am following this Twilio tutorial on how to reply to SMS messages with my app:
https://www.twilio.com/docs/sms/tutorials/how-to-receive-and-reply-node-js
The tutorial assumes you're using Express, but I am doing this with a Cloud Function, so my code looks a bit different:
exports.sms = functions.https.onCall((req: any, res: any) => {
const twiml = new MessagingResponse();
if (req.body.Body === 'hello') {
twiml.message('Hi!');
} else if (req.body.Body === 'bye') {
twiml.message('Goodbye');
} else {
twiml.message(
'No Body param match, Twilio sends this in the request to your server.',
);
}
res.writeHead(200, { 'Content-Type': 'text/xml' });
res.end(twiml.toString());
});
When I text my Twilio #, it hits that endpoint, but I get the following error:
Request has incorrect Content-Type. application/x-www-form-urlencoded
How do I get around this?
It looks like you're mixing up callable type functions and normal HTTP type functions. Please read the documentation to understand the difference. Callable functions are intended to be invoked directly from your mobile app using the provided client SDK. They provide two arguments: an input data object, and a context. Callables do NOT provide "req" and "res". If you want control over the the response, you should be using a normal HTTP function with "onRequest" instead of "onCall".
I have registered my web address (let's just call it https://mywebaddress/callbacks) with this external API and it will now send me JSON when it completes an action. I don't need to initiate anything outbound to it, I just need to receive the JSON and store it.
EDIT:
JSON data will be receive via POST
Paul's link sent me in the right direction. (http://www.meteorpedia.com/read/REST_API).
Then I found the section titled "WebApp.connectHandlers and connect".
I used the code found there, but in my instance there was an error in the code. I had to change the first line from var connect = Npm.require('connect'); to var connect = Meteor.require('connect');
Here is the code below.
// necessary to parse POST data
var connect = Meteor.require('connect');
// necessary for Collection use and other wrapped methods
var Fiber = Npm.require('fibers');
WebApp.connectHandlers
.use(connect.urlencoded()) // these two replace
.use(connect.json()) // the old bodyParser
.use('/getUserProfile', function(req, res, next) {
// necessary for Collection use and other wrapped methods
Fiber(function() {
var userId = req.body.userId;
var user = Meteor.users.findOne(userId);
res.writeHead(200, {'Content-Type': 'application/json'});
res.end(JSON.stringify(user.profile));
}).run();
});
}
Then to test that this was working I used http://www.hurl.it/. I changed the destination to POST and added a header of content-type - application/json. I then pasted in the body some JSON that I knew came from balanced. If you need a tool to see what is actually being posted to your server you can use http://requestb.in/.
Currently, I use the built-in meteor http method (see http://docs.meteor.com/#http) for issuing http calls, on both my client and my server.
However, I'm experiencing two issues:
is it possible to cancel a request?
is it possible to have multiple query parameters which share the same key?
Are these just Meteor limitations, or are there ways to get both to work using Meteor?
I know I could you jquery on the clientside, and there must be a server-side solution which supports both as wel, but I'd prefer sticking with meteor code here.
"is it possible to cancel a request?"
HTTP.call() does not appear to return an object on which we could call something like a stop() method. Perhaps a solution would be to prevent execution of your callback based on a Session variable?
HTTP.call("GET", url, function(error, result) {
if (!Session.get("stopHTTP")) {
// Callback code here
}
});
Then when you reach a point where you want to cancel the request, do this:
Session.set("stopHTTP", true);
On the server, instead of Session perhaps you could use an environment variable?
Note that the HTTP.call() options object does accept a timeout key, so if you're just worried about the request never timing out, you can set this to whatever millisecond integer you want.
"is it possible to have multiple query parameters which share the same key?"
Yes, this appears to be possible. Here's a simple test I used:
Meteor code:
HTTP.call("GET", "http://localhost:1337", {
query: "id=foo&id=bar"
}, function(error, result) {
// ...
});
Separate Node.js server: (just the basic example on the Node.js homepage, with a console.log line to output the request URL with query string)
var http = require('http');
http.createServer(function(req, res) {
console.log(req.url); // Here I log the request URL, with the query string
res.writeHead(200, {
'Content-Type': 'text/plain'
});
res.end('Hello World\n');
}).listen(1337, '127.0.0.1');
console.log('Server running at http://127.0.0.1:1337/');
When the Meteor server is run, the Node.js server logged:
/?id=foo&id=bar
Of course, this is only for GET URL query parameters. If you need to do this for POST params, perhaps you could store the separate values as a serialized array string with EJSON.stringify?
I am building a registration form (passport-local as authentication, forms as form helper).
Because the registration only knows GET and POST I would like to do the whole handling in one function.
With other words I am searching after something like:
exports.register = function(req, res){
if (req.isPost) {
// do form handling
}
res.render('user/registration.html.swig', { form: form.toHTML() });
};
The answer was quite easy
exports.register = function(req, res) {
if (req.method == "POST") {
// do form handling
}
res.render('user/registration.html.swig', { form: form.toHTML() });
};
But I searched a long time for this approach in the express guide.
Finally the node documentation has such detailed information:
http://nodejs.org/api/http.html#http_http_request_options_callback
Now you can use a package in npm => "method-override", which provides a middle-ware layer that overrides the "req.method" property.
Basically your client can send a POST request with a modified "req.method", something like /registration/passportID?_method=PUT.
The
?_method=XXXXX
portion is for the middle-ware to identify that this is an undercover PUT request.
The flow is that the client sends a POST req with data to your server side, and the middle-ware translates the req and run the corresponding "app.put..." route.
I think this is a way of compromise. For more info: method-override