In Nodejs, I am trying to parse json data in node http.createServer post request. I am following this tutorial and written followig code.
var data;
req.on('data', function(chunk) {
data = JSON.parse(chunk.toString()); // parsing request body json object
});
req.on('end', function() {
console.log(data);
});
Where I am parsing data, it is giving me syntax error SyntaxError: Unexpected number in JSON at position 1
I have also tried converting this line into following.
var data, value = {};
req.on('data', chunk => {
value = chunk.toString(); // parsing request body json object
data = JSON.parse(value);
});
Related
So I have an rss feed url, that has around 200 items. However, request module is only able to fetch at random 15 - 20 items, and it ends in the middle of receiving the response without giving any error.
I tried with regular curl, and I am receiving all the data, any reason for this descrepancy?
const { request } = require('https');
const url = //some url;
const req = request(url, (res) => {
console.log(res.statusCode)
let data = "";
res.on('data', (d) => {
data += d;
})
res.on('end', () => {
console.log('data ---', data);
})
})
req.end();
I tried with request npm package, and it's still the same
//route to search (POST http://localhost:8080/api/search)
apiRoutes.post('/search', function(req, res) {
console.log('search');
var query = req.params;
console.log(query);
options = {
protocol : "https:/",
host: "https://api.themoviedb.org",
path: "/3/search/movie?api_key=35f7a26be584f96e6b93e68dc3b2eabd&language=en-US&page=1&include_adult=false&query="+query,
};
var req = https.request(options, function(res) {
var chunks = [];
res.on("data", function (chunk) {
chunks.push(chunk);
});
res.on("end", function () {
var body = Buffer.concat(chunks);
console.log(body.toString());
});
});
req.write("{}");
req.end();
})
DOES ANYONE KNOW WHERE THE PROBLEM IS?
I'm trying to do a request to do a research to the api the movie db and get the result back
There are some problems with the code. I have tested it and made it to work.
let options = {
host: "api.themoviedb.org",
path: "/3/search/movie?api_key=35f7a26be584f96e6b93e68dc3b2eabd&language=en-US&page=1&include_adult=false&query="+query.data.replace(' ','%20'),
};
first of all since you are using https module you don't need to specify the protocol nor you need to put it in the url. That's how your options variable should be.
Second you are appending the entire query object to the url which is {} instead you should append a string which will be in one of the key of your query object in my case its query.data
Third if there are spaces in the string Eg: Home Alone you to maintain space and avoid the error we replace the string with %20 which is a escaping character.
Forth Try giving a unique name for https request variable and its response variable in the callback function or it will override the route's req res variables cause your code to not work. Notice how I have used route's res function to send the data back and end the response
Also I am getting the data in req.body and you are using req.params however there are no params defined in your routes. Try going through the documentation for more information
Here is the complete code
apiRoutes.post('/search',function (req, res) {
https = require('https');
var query = req.body;
console.log(query.data);
let options = {
host: "api.themoviedb.org",
path: "/3/search/movie?api_key=35f7a26be584f96e6b93e68dc3b2eabd&language=en-US&page=1&include_adult=false&query="+query.data.replace(' ','%20'),
};
var request = https.request(options, function(response) {
var chunks = [];
response.on("data", function (chunk) {
chunks.push(chunk);
});
response.on("end", function () {
var body = Buffer.concat(chunks);
console.log(body.toString());
res.send(body);
res.end()
});
});
request.end();
});
Hope it helps.
I am using https.request() to make a HTTPS request using the following familiar pattern:
var request = https.request(options, function (response) {
var chunks = [];
response.on('data', function (chunk) {
chunks.push(chunk);
});
response.on('end', function () {
var buffer = Buffer.concat(chunks);
...
});
});
...
request.end();
...
Once I have the finished response Buffer, it needs to be packaged into a JSON object. The reason for this is because I am creating a kind of tunnel, whereby the HTTP response (its headers, status, and body) are to be sent as JSON through another protocol.
So that both textual and binary responses may be supported, what works for me so far is to encode the Buffer to Base64 (using buffer.toString('base64')) and unencode it at the other end using new Buffer(theJsonObject.body, 'base64'). While this works, it would be more efficient if I could selectively only perform Base64 encoding if the HTTP request response is known to be of binary type (e.g. images). Otherwise, in the https.request() callback shown above, I could simply do chunk.toString() and convey the response body in the JSON object as a UTF-8 string type. My JSON object would probably contain an additional property that indicates to the opposite end of the tunnel whether the 'body' is a UTF-8 string (e.g. for .htm, .css, etc.) or a Base64-encoded (e.g. images).
What I could do is try to use the MIME type in the response content-type header to work out whether the response is going to be binary. I would probably maintain a 'white list' of types that I know it's safe to assume are UTF-8 (such as 'text/html' and so on). All others (including e.g. 'image/png') would be Base64-encoded.
Can anyone propose a better solution?
Could you use the file-type package to detect the file type by checking the magic number of the buffer?
Install
npm install --save file-type
Usage
var fileType = require('file-type');
var safeTypes = ['image/gif'];
var request = https.request(options, function (response) {
var chunks = [];
response.on('data', function (chunk) {
chunks.push(chunk);
});
response.on('end', function () {
var buffer = Buffer.concat(chunks);
var file = fileType(buffer) );
console.log( file );
//=> { ext: 'gif', mime: 'image/gif' }
// mime isn't safe
if ( safeTypes.indexOf(file.mime) == '-1' ) {
// do your Base64 thing
}
});
});
...
request.end();
...
If you want to keep your code package free have a look at the package source on Github, it's pretty minimal.
I use node https module to get auth information from another server, I get the result is "result=undefined{a:...,b:...}", so I can't use JSON.parse to parse the result data, but if I use "JSON.parse(body.substr(9))", I can get the right result.
For more information, if I use a post tool to fetch the result, I get the result type is "application/json" and the result is the right json object. I use the following code to fetch post result.
var options={
hostname:...,
port:null,
path:...,
method:'post',
rejectUnauthorized:false,
requestCert:true,
agent:false
}
var https.request(options,function(res){
var body;
res.on('data',function(chunk){
body+=chunk;
});
res.on('end',function(){
console.log(JSON.parse(body));
});
});
You should initialize body with an empty string:
var body = '';
because otherwise, the first time
body+=chunk;
is called, body is undefined and gets concatenated as the "undefined" string:
> var body;
undefined
> body += "{}"
'undefined{}'
> var body = '';
undefined
> body += "{}"
'{}'
I'm trying to make a chain of promises functions which use HTTP requests in NodeJS with Kraken framework.
My code could work in 90% of cases, but if the distant requested server takes time to respond, the code will return an error with undefined values. So I think Q is a good solution to prevent that.
Here's the situation :
We access to a URL with a "code" parameter -> the route controller takes this param to use it in a HTTP POST request -> the response (a token) is stored in a variable and used in an other HTTP GET request -> the response (multiple JSON objects) is stored in variable too -> all variables are stored in a MongoDB.
If functions are not used in this order, of course it fails.
var Q = require('q');
module.exports = function (router) {
router.get('/', function (req, res) {
var codein = req.param('code');
if(codein){
console.log('Provided code: ' + codein+'\n');
getAccessToken(codein).then(function(token){
console.log('Provided AccessToken: ' + token + '\n');
getUsername(token).then(function(userdata){
console.log('Provided Username: ' + JSON.parse(userdata).username + '\n');
storeData(userdata).then(function(msg){
console.log(msg);
res.redirect('/dashboard/' + JSON.parse(userdata).username);
});
});
});
}
else{
console.log('Access Denied, redirecting...');
res.redirect('/');
}
});
};
This method works, but actually didn't resolve the problem, because sometimes variable are undefined again. I think it's my request functions which aren't well made...
Here's an example of the first function with POST request :
var getAccessToken = function(cod){
var def = Q.defer();
var data = querystring.stringify({
client_id:"1234567890",
client_secret:"******",
grant_type:"authorization_code",
redirect_uri:"http://localhost:8000/r/callback",
code:cod
});
var options = {
host: 'domain.server.com',
port: 443,
path: '/api/oauth2/token',
method: 'POST',
headers: {
'Content-Type': 'application/x-www-form-urlencoded',
'Content-Length': Buffer.byteLength(data)
}
};
var response = "";
var req = https.request(options, function(res) {
res.setEncoding('utf8');
res.on('data', function (chunk) {
response += chunk;
});
res.on('end', function(){
var json = JSON.parse(response);
var acto = json.access_token;
def.resolve(acto);
});
});
req.write(data);
req.end();
return def.promise;
};
In this case the acto variable can be undefined... So am I using Q in a wrong way ?
EDIT
To understand my problem, let me show you what can I have in my output console (really rare but happens) :
Provided code: 12345678910
Provided Username: user543210
Instead of :
Provided code: 12345678910
Provided AccessToken: 9876543210
Provided Username: user
I think you need to account for 2 scenarios
Where the Twitch API takes time to respond.
The Twitch response cannot be parsed
The code
res.on('end', function(){
var json = JSON.parse(response);
var acto = json.access_token;
def.resolve(acto);
});
Should be modified as:
try {
var json = JSON.parse(response);
var acto = json.access_token;
//check if acto is undefined
if (acto === undefined) {
def.reject('Some error message');
} else {
def.resolve(acto);
}
} catch (error) {
//since the JSON could not be parse
def.reject(error);
}