I'm looking for away to send multiple images in one GET request from an Expressjs server through an api.
I want to create an image gallery of each users uploaded images in a MEAN stack. When images are uploaded using multer, the image information is saved to mongodb, including the userid of whoever uploaded it.
When on angularjs, I want user to have access to any of the images they have previously uploaded. Currently I'm sending one file on a GET request based on user id. Is there anyway of sending multiple files in one json. I'm currently using Expressjs's res.sendFile, but haven't found any info about sending multiple back yet.
https://expressjs.com/en/api.html#res.sendFile
Here is my current get request:
exports.getUpload = function(req, res) {
Upload.find({createdby: req.params.Id}).exec(function(err, upload) {
errorhandle.errorconsole(err, 'file found');
console.log(upload[0]);
var options = {
root: '/usr/src/app/server/public/uploads/images'
};
var name = "" + upload[0].storedname +"";
console.log(name);
res.sendFile(name, options,function(err) {
errorhandle.errorconsole(err, 'file sent');
});
});
};
You can't with res.sendFile. In fact I don't think you can at all. Maybe with HTTP/2 Server Push
, but I'm not sure.
What you can do is send a JSON response with a link to all the images:
exports.getUpload = async (req, res) => {
const uploads = await Upload.find({ createdby: req.params.Id }).exec()
const response = uploads.map(image => {name: `https://example.com/uploads/images/${image.storedname}`})
res.json(response)
}
Note error handling omitted.
Related
I want to allow users request audio files. The files are hosted on a separate file server. I don't want users to get these files unless they've gone through my server first.
How do I make a function that basically acts as a middle man between the user and the file server. I currently have something like this:
async (req, res) => {
const mediaLink = `https://www.example.com/audio.mp3`;
const mediaResponse = await fetch(mediaLink, {
headers: {
Range: req.headers.range,
}
});
const blob = await mediaResponse.blob(); // I'm guessing here. Idk.
res.send(blob);
}
I tested this in an <audio> tag but the audio never loaded:
<audio controls src="http://localhost:5001/file-server-middleware" />
The correct way to handle such a request would be to pipe the response body back to the client making sure to copy across any relevant headers that may be in the response from the file server. Read up on the HTTP Functions documentation to see what use cases you should be looking out for (e.g. CORS).
async (req, res) => {
const mediaLink = `https://www.example.com/audio.mp3`;
// You may wish to pass through Cache-related headers, such as
// If-None-Match, If-Match, If-Modified-Since, If-Range, If-Unmodified-Since
const mediaResponse = await fetch(mediaLink, {
headers: {
Range: req.headers.range,
}
});
// note: this currently passes the body & status from the file server
// as-is, you may want to send your own body on failed status codes to
// hide the existence of the external server (i.e. custom 404 pages, no
// Nginx error pages, etc)
// mediaResponse.status may be:
// - 200 (sending full file)
// - 206 (sending portion of file)
// - 304 (not modified, if using cache headers)
// - 404 (file not found)
// - 412 (precondition failed, if using cache headers)
// - 416 (range not satisfiable)
// - 5xx (internal server errors from the file server)
res
.status(mediaResponse.status)
.set({
/* ... other headers (e.g. CORS, Cache-Control) ... */
'Content-Type': mediaResponse.headers.get('content-type'),
'Content-Length': mediaResponse.headers.get('content-length'),
'Content-Encoding': mediaResponse.headers.get('content-encoding'),
'Etag': mediaResponse.headers.get('Etag'), // for caching
'Last-Modified': mediaResponse.headers.get('last-modified') // for caching
});
mediaResponse.body.pipe(res);
}
You may also want to look into the various express-compatible proxy modules that can handle the bodies and headers for you. Note that some of these may not function properly if used in a Firebase Cloud Function as the request bodies are automatically consumed for you.
Trying to embed kin.js in an Ionic App, I can see that the key creation using Keypairs and network initialization is ok
const keys = Keypair.random();
const network = KinNetwork.Production;
However when I try to create the wallet
createWallet(network, keys)
.then(res => {
console.log(res);
}, (err) => {
console.log(err)
});
It keeps retrying but at the end it replies with Error: failed to load account:
I can see the API call is made
https://horizon-kin-ecosystem.kininfrastructure.com/accounts/GANWXV7IHG6YGWVIXJNB56OCBIYI7LYKD34CH556YCDOP5LRC2WDJLTC?c=0.32263221858689695
but the response includes this object
{
“type”: “https://stellar.org/horizon-errors/not_found",
“title”: “Resource Missing”,
“status”: 404,
“detail”: “The resource at the url requested was not found. This is usually occurs for one of two reasons: The url requested is not valid, or no data in our database could be found with the parameters provided.”
}
Any missing parameters I should supply beyond the network and keys
I am trying to use Microsoft Azure Storage SDK for Node.js and JavaScript for Browsers (https://github.com/Azure/azure-storage-node) to display PDF contents stored in Azure blob in browsers. So far I couldn't find any examples on how to do it.
I tried to follow the suggestion from https://github.com/Azure/azure-storage-node/issues/440, But couldn't make it work. I am using Azure function.
module.exports = async function (context, req) {
let accessToken = await getAccessToken();
let container = req.params.container;
let filename = req.params.filename;
let tokenCredential = new azure.TokenCredential(accessToken);
let storageAccountName = process.env.StorageAccountName;
let blobService = azure.createBlobServiceWithTokenCredential(`https://${storageAccountName}.blob.core.windows.net/`, tokenCredential);
return new Promise((resolve, reject) => {
let readStream = blobService.createReadStream(container, filename, function (error, result, response) {
if (error) {
context.log(error);
context.log(response);
context.res = {
status: 400,
body: response
};
resolve(context.res);
}
});
let body = '';
readStream.on('data', (chunk) => {
body += chunk;
});
readStream.on('end', () => {
context.res = {
headers: {
'Content-Type': "application/pdf"
},
body: body
};
resolve(context.res);
});
});
};
But I got "Couldn't open PDF" error message in the browser or timeout error.
For downloading blob in browser environment, using URL with SAS is recommended, and in the framework you are using, would an accessible URL pointing to PDF be enough?
Please follow example:
Download Blob
BlobService provides interfaces for downloading a blob into browser memory. Because of browser's sandbox limitation, we cannot save the downloaded data trunks into disk until we get all the data trunks of a blob into browser memory. The browser's memory size is also limited especially for downloading huge blobs, so it's recommended to download a blob in browser with SAS Token authorized link directly.
Shared access signatures (SAS) are a secure way to provide granular access to blobs and containers without providing your storage account name or keys. Shared access signatures are often used to provide limited access to your data, such as allowing a mobile app to access blobs.
I'm trying to execute API.AI tutorial for building a weather bot for Google Assistant (the one here: https://dialogflow.com/docs/getting-started/basic-fulfillment-conversation)
I made everything successfully, created the bot within API, created the Fulfillments, installed NodeJS on my pc, connected Google Cloud Platform, etc.
Then I created the index.js file by copying it exactly how it's stated on API.ai tutorial with my API key from World Weather Organisation (see below).
But when I use the bot, it doesn't work. On the Google Cloud Platform the error is always the same:
Error: getaddrinfo ENOTFOUND api.worldweatheronline.com
api.worldweatheronline.com:80
at errnoException (dns.js:28)
at GetAddrInfoReqWrap.onlookup (dns.js:76)
No matter how often I do it I get the same error. So I don't actually reach the API. I tried to see if anything changed from WWO side (URL, etc.) but apparently no. I updated NodeJS and still same issue. I refreshed the Google Cloud platform completely and didn't help.
That one I really can't debug. Could anyone help?
Here's the code from API.ai:
'use strict';
const http = require('http');
const host = 'api.worldweatheronline.com';
const wwoApiKey = '[YOUR_API_KEY]';
exports.weatherWebhook = (req, res) => {
// Get the city and date from the request
let city = req.body.result.parameters['geo-city']; // city is a required param
// Get the date for the weather forecast (if present)
let date = '';
if (req.body.result.parameters['date']) {
date = req.body.result.parameters['date'];
console.log('Date: ' + date);
}
// Call the weather API
callWeatherApi(city, date).then((output) => {
// Return the results of the weather API to Dialogflow
res.setHeader('Content-Type', 'application/json');
res.send(JSON.stringify({ 'speech': output, 'displayText': output }));
}).catch((error) => {
// If there is an error let the user know
res.setHeader('Content-Type', 'application/json');
res.send(JSON.stringify({ 'speech': error, 'displayText': error }));
});
};
function callWeatherApi (city, date) {
return new Promise((resolve, reject) => {
// Create the path for the HTTP request to get the weather
let path = '/premium/v1/weather.ashx?format=json&num_of_days=1' +
'&q=' + encodeURIComponent(city) + '&key=' + wwoApiKey + '&date=' + date;
console.log('API Request: ' + host + path);
// Make the HTTP request to get the weather
http.get({host: host, path: path}, (res) => {
let body = ''; // var to store the response chunks
res.on('data', (d) => { body += d; }); // store each response chunk
res.on('end', () => {
// After all the data has been received parse the JSON for desired data
let response = JSON.parse(body);
let forecast = response['data']['weather'][0];
let location = response['data']['request'][0];
let conditions = response['data']['current_condition'][0];
let currentConditions = conditions['weatherDesc'][0]['value'];
// Create response
let output = `Current conditions in the ${location['type']}
${location['query']} are ${currentConditions} with a projected high of
${forecast['maxtempC']}°C or ${forecast['maxtempF']}°F and a low of
${forecast['mintempC']}°C or ${forecast['mintempF']}°F on
${forecast['date']}.`;
// Resolve the promise with the output text
console.log(output);
resolve(output);
});
res.on('error', (error) => {
reject(error);
});
});
});
}
Oh boy, in fact the reason was most stupid ever. I didn't enable "billing" on Google Cloud Platform and that's why it blocked everything (even though I'm using a free test of the API). They just wanted my credit card number. It works now
I had the same issue trying to hit my db. Billing wasn't the fix as I had billing enabled already.
For me it was knexfile.js setup for MySql - specifically the connection object. In that object, you should replace the host key with socketPath; and prepend /cloudsql/ to the value. Here's an example:
connection: {
// host: process.env.APP_DB_HOST, // The problem
socketPath: `/cloudsql/${process.env.APP_DB_HOST}`, // The fix
database: process.env.APP_DB_NAME,
user: process.env.APP_DB_USR,
password: process.env.APP_DB_PWD
}
Where process.env.APP_DB_HOST is your Instance connection name.
PS: I imagine that even if you're not using Knex, the host or server parameter of a typical DB connectionstring will have to be called socketPath when connecting to Google Cloud SQL.
I want to use the request module in my express app, but I am not sure where the actual requests code goes.
Usage:
When a user loads a page, make a GET request and populate the page with data.
When a users clicks on a item from a table, make a GET request.
When a user fills out a form, POST.
I tried searching for answers but it seems to be implied that the developer knows where to place the code.
Example of a code snippet using request that I am unsure where to place in the express app:
var request = require('request');
request('http://www.google.com', function (error, response, body) {
if (!error && response.statusCode == 200) {
console.log(body) // Show the HTML for the Google homepage.
}
})
I am guessing that I should not place the code in the server.js file especially if I am going to be making many different calls, but that's what it looks like others are doing on StackOverflow.
Does the request belong in a model?
If you are doing this in response to a user interaction, like clicking on something you can just do it from the route handler. Below, I just return the results to the client, or I pass an error to the next handler in the chain.
var request = require('request');
var express = require('express');
var app = express();
app.get('/click', function(req, res, next){
request('http://www.google.com', function (error, response, body) {
if (error || response.statusCode != 200)
return next(err);
response.send(body) // return the html to the client
})
});
app.listen(3000);
In bigger apps you might move routes into separate modules.