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forward upload image request using multer (javascript, express)

I am using the express server as an API gateway to my microservices, in which I am processing images and store them in a database.
the problem summarizes as follows:
in the express server, I need to forward the image received in a post request from the client and forward it to the web service that can handle image processing.
It turns out that I need to parse the image before I can forward it to the next API, the error I am getting is
Unexpected token - in JSON at position 0
Her is my client that sends the image to the express server(my gateway)
function uploadWithFormData() {
const formData = new FormData();
formData.append("file", file);
fetch('/upload', {
method: "POST",
headers: {
"content-type": "application/json",
},
body: data
}).then(handleResponse)
.catch(handleError);
uploadImage(formData);
}
and this is my express serve that should handle the request and forward it to another web service
app.post("/upload", function (req, res) {
const form = formidable({ multiples: true });
form.parse(req, (err, fields, files) => {
const response = res.json({ fields, files });
let formData = new FormData();
formData.append('file', fs.createReadStream(req.files.file.path), req.files.file.name);
uploadImageAPI(response).then(
res.status(201).send()
).cache(res.status(412).send())
});
I have tried to make some consol.log inside the function to see the req but the request fails before it enters the function, because express could not pars the image.
I saw some people doing this using the multer library but I could not mange that in my case
any suggestions?

You're posting a FormData object, which will be converted to multipart/form-data.
You aren't posting JSON.
You have set "content-type": "application/json" so you claim you are posting JSON.
The server tries to decode the "JSON", fails, and throws the error.
Don't override the Content-Type header. fetch will generate a suitable one automatically when you pass it a FormData object.
Do use a body parsing module which supports multipart requests. body-parser does not, but its documentation links to several that do.

Part of the solution is to remove the JSON header as #Quentin said in his answer. However, the code that solved the problem is as following :
const multer = require('multer');
const upload = multer();
app.post("/upload", upload.any(), (req, res) => {
const { headers, files } = req;
const { buffer, originalname: filename } = files[0];
headers['Content-Type'] = 'multipart/form-data';
const formFile = new FormData();
formFile.append('file', buffer, { filename });
fetch(URL, {
method: "POST",
body: data
}).then(handleResponse)
.catch(handleError);
});

Javascript AzureAd Consume Rest Service

RestAPI: I have a Rest API running Asp Core with AzureAd Authentication.
WebApp: I have a separate WebApplication running Asp Core as backend, with Javascript frontend.
The WebApp backend authenticates through AzureAd, and then against the RestAPI to check if a user is registred.
I want the javascript client to be able to consume the Rest API directly. How should i go about this without exposing the accesstoken?
I could go about sending the request from Javascript to WebApp Backend -> Rest API. But i really want to avoid this, because of unnecessary code.

In this scenario, you can try to implement ADAL for js in your JS client. Leveraging **adal** to gain the authentication token, and when you call your Web Api, it will add the authentication header in HTTP requests.
E.G.
Suppose we want to call the Microsoft Graph API from our JS client.we develop a node.js script that uses request to call the Microsoft Graph API for groups to create a new Security Group.
The following code shows how the API is consumed from that script. Note that the token and the name are passed by parameter. Additionally, this function returns a Promise that is successfully resolved when the group is correctly created and rejected when is not.
var request = require('request');
function createGroup(token, name) {
return new Promise((resolve, reject) => {
const options = {
method: 'POST',
url: 'https://graph.microsoft.com/v1.0/groups/',
headers: {
'Authorization': 'Bearer ' + token,
'content-type': 'application/json'
},
body: JSON.stringify({
"displayName": name,
"mailEnabled": false,
"securityEnabled": true
})
};
request(options, (error, response, body) => {
const result = JSON.parse(body);
if (!error && response.statusCode == 204) {
resolve(result.value);
} else {
reject(result);
}
});
});
}
In order to call Microsoft Graph API, we needed to be authenticated and that is why in the previous section we have a token as a parameter of the function which was used to perform the request.
we should add the following code to generate the token. Note that we are using the adal npm package to do this easier, calling the acquireTokenWithClientCredentials method of the AuthenticationContext object. Additionally, we have some constants that need to be updated with the client id and secret obtained before as well as the tenant name.
var adal = require('adal-node');
const TENANT = "{tenant-name-here}.onmicrosoft.com";
const CLIENT_ID = "{Application-id-here}";
const CLIENT_SECRET = "{Application-key-here}";
function getToken() {
return new Promise((resolve, reject) => {
const authContext = new adal.AuthenticationContext(`https://login.microsoftonline.com/${TENANT}`);
authContext.acquireTokenWithClientCredentials(GRAPH_URL, CLIENT_ID, CLIENT_SECRET, (err, tokenRes) => {
if (err) { reject(err); }
resolve(tokenRes.accessToken);
});
});
Hope it helps.

How to upload a file in to object storage using node js call

Iam trying to create a post call which basically takes a file(eg img,pdf file) and then it need to upload in to object storage on bluemix.I was able to authenticate and get the token and create the authurl.I just need to pass file which we upload along with the url.But Iam out of ideas how I can get the file uploaded from postman to be passed to that url with in the post call..Below is my code
app.post('/uploadfile',function(req,res){
getAuthToken().then(function(token){
if(!token){
console.log("error");
}
else{
var fileName = req.body.file;
console.log("data",file);
console.log(SOFTLAYER_ID_V3_AUTH_URL,"url");
var apiUrl = SOFTLAYER_ID_V3_AUTH_URL + config.projectId + '/' + containerName + fileName ;
url : apiurl,
method :'PUT',
headers :{
'X-Auth-Token': token
},function(error, response, body) {
if(!error && response.statusCode == 201) {
res.send(response.headers);
} else {
console.log(error, body);
res.send(body);
}
}
}
})
});
Can someone help here.

Since you're using Express, you should use something like:
https://www.npmjs.com/package/express-fileupload
https://github.com/mscdex/connect-busboy
https://github.com/expressjs/multer
https://github.com/andrewrk/connect-multiparty
https://github.com/mscdex/reformed
Without a body parser that handles file uploads you will not be able to get the uploaded file in the Express request handler.
Then, you need to pass the uploaded file to the request that you're making.
For that you should use this module:
https://www.npmjs.com/package/bluemix-object-storage
There is no need to reinvent the wheel when there are tested and eay to use solutions available. Especially when you're dealing with sensitive information like API keys and secrets I would not advice you to implement your own solution from scratch, unless you really know what you're doing. And if you really know what you're doing, then you don't need to seek advice for things like that.

Here is the official Object Storage SDK for Node.js:
https://github.com/ibm-bluemix-mobile-services/bluemix-objectstorage-serversdk-nodejs
Connect to Object Storage:
var credentials = {
projectId: 'project-id',
userId: 'user-id',
password: 'password',
region: ObjectStorage.Region.DALLAS
};
var objStorage = new ObjectStorage(credentials);
Create a container:
objstorage.createContainer('container-name')
.then(function(container) {
// container - the ObjectStorageContainer that was created
})
.catch(function(err) {
// AuthTokenError if there was a problem refreshing authentication token
// ServerError if any unexpected status codes were returned from the request
});
}
Create a new object or update an existing one:
container.createObject('object-name', data)
.then(function(object) {
// object - the ObjectStorageObject that was created
})
.catch(function(err) {
// TimeoutError if the request timed out
// AuthTokenError if there was a problem refreshing authentication token
// ServerError if any unexpected status codes were returned from the request
});

Send result from HTTP request in Angular to NodeJS

I am currently sending a request from NodeJS to get some data, as such :
In Angular :
$http.post(API_ENDPOINT.url + '/annonce', {'link': url}).then(function (result) {
...
}
And in Node :
apiRoutes.post('/annonce', function (req, res) {
const url = req.body.link
request.get({
uri: url,
encoding: null
}, function (error, response, html) {
if (!error) {
res.send(parser(url, html))
}
})
return res
})
I would like to send this request from my front-end (Angular). I guess I could simply do the request like this :
$http.get(url).then(function(result)) {
// send another post request to the back end with the result
}
but I've heard it was easier to use pipes in this case.
Thing is, I really don't understand how to make it work. Can anyone help ?

If the page you are trying to retrieve does not have the CORS headers then angular will fail to make the request.
If you expand on your usecase it should be easier to get you some help.

Can't create Braintree client token with customer ID

Copied directly from Braintree's tutorial, you can create a client token with a customer ID like this:
gateway.clientToken.generate({
customerId: aCustomerId
}, function (err, response) {
clientToken = response.clientToken
});
I declare var aCustomerId = "customer" but node.js closes with the error
new TypeError('first argument must be a string or Buffer')
When I try to generate a token without the customerId, everything works fine (though I never get a new client token but that's another question).
EDIT: Here is the complete test code as requested:
var http = require('http'),
url=require('url'),
fs=require('fs'),
braintree=require('braintree');
var clientToken;
var gateway = braintree.connect({
environment: braintree.Environment.Sandbox,
merchantId: "xxx", //Real ID and Keys removed
publicKey: "xxx",
privateKey: "xxx"
});
gateway.clientToken.generate({
customerId: "aCustomerId" //I've tried declaring this outside this block
}, function (err, response) {
clientToken = response.clientToken
});
http.createServer(function(req,res){
res.writeHead(200, {'Content-Type': 'text/html'});
res.write(clientToken);
res.end("<p>This is the end</p>");
}).listen(8000, '127.0.0.1');

Disclaimer: I work for Braintree :)
I'm sorry to hear that you are having trouble with your implementation. There are a few things that might be going wrong here:
If you specify a customerId when generating a client token, it must be a valid one. You do not need to include a customer id when creating a client token for a first time customers. Typically you would create create a customer when handling the submission of your checkout form, and then store that customer id in a database for use later. I'll talk to our documentation team about clarifying the documentation around this.
res.write takes a string or a buffer. Since you were writing response.clientToken, which was undefined because it was created with an invalid customer id, you were receiving the first argument must be a string or Buffer error.
Some other notes:
If you create a token with an invalid customerId, or there is another error processing your request, response.success will be false, you can then inspect the response for the reason why it failed.
You should generate your client token within the http request handler, this will allow you generate different tokens for different customers, and to better handle any issues that result from your request.
The following code should work, provided you specify a valid customerId
http.createServer(function(req,res){
// a token needs to be generated on each request
// so we nest this inside the request handler
gateway.clientToken.generate({
// this needs to be a valid customer id
// customerId: "aCustomerId"
}, function (err, response) {
// error handling for connection issues
if (err) {
throw new Error(err);
}
if (response.success) {
clientToken = response.clientToken
res.writeHead(200, {'Content-Type': 'text/html'});
// you cannot pass an integer to res.write
// so we cooerce it to a string
res.write(clientToken);
res.end("<p>This is the end</p>");
} else {
// handle any issues in response from the Braintree gateway
res.writeHead(500, {'Content-Type': 'text/html'});
res.end('Something went wrong.');
}
});
}).listen(8000, '127.0.0.1');