I want to use fs.WriteFile in my JS project. I am building an algorithm that outputs random data and I want to give the user the opportunity to save the data as a txt file. I have been able to implement fs.WriteFile in my project, but I have a couple of questions on how to proceed next as the function remains somewhat unclear.
How do I specify that I want to include the contents of various vars? Is it as simple as data = let1 + let2 + let3 and all of the data will be included?
can I add the current date and time in the .txt file name? If so, how?
How do I tell writeFile to save the contents to a .txt file and open a download blob so that people can specify their own download locations?
Thanks in advance!
I've tried looking at basic documentation but its mainly the same: a template using a simple string that saves into the same directory, which is what I don't want.
For you first question, you are correct. You can just combine different string variables into a larger string variable. See the documentation for string concatenation for more information.
For your second question, yes you can. You can get the current date and time with new Date() and turn it into a variety of formats. For file names, using mydate.toISOString() will probably be the most clean.
Here's an example of both of these in practice:
import fs from 'fs';
// Here's some data that we want to put in the file.
const name = "Bob";
const age = 43;
// Create the data we want to put in our file.
const data = name + '\n' + age;
// Let's grab the date and use it as part of our file name.
const date = new Date();
const fileName = `${date.toISOString()}.txt`;
// Call fs.writeFile to put the data in the file.
fs.writeFile(fileName, data, () => {
console.log(`Wrote data to ${fileName}.`);
});
Your third question is more complicated and probably worth a separate post. fs.writeFile can't do this for you. You'll have to come up with some mechanism for the user to enter their own file name and build off of that.
Edit:
To address your question in the comments, you might be a little confused with how NodeJS works. NodeJS runs on the server and doesn't have any way to deal with buttons or UIs by default like browser JavaScript does. It might be helpful to look at the differences between the two. So you won't be able to save it to the downloads folder on a button click.
With that said, we can save the file to the user's Downloads folder with the same script I posted above by adding the path to the Downloads folder to the beginning of the file name.
Here's the code above adjusted to do that:
import fs from 'fs';
import os from 'os'; // NEW
import path from 'path'; // NEW
const name = "Bob";
const age = 43;
const data = name + '\n' + age;
const date = new Date();
const fileName = `${date.toISOString()}.txt`;
// Get the user's home directory.
const homedir = os.homedir();
// Append the Downloads directory and fileName to the user's home directory.
const fullPath = path.join(homedir, 'Downloads', fileName);
// Use fullPath here instead of fileName.
fs.writeFile(fullPath, data, () => {
console.log(`Wrote data to ${fileName}.`);
});
Related
I have a process where a client uploads a document. This document can be in the form of a PDF, JPG or PNG file only and it should be reuploaded once a year (it is an errors and omissions insurance policy).
I am saving this file in a container.
For deleting files from anywhere at the application, I have this function (Node):
deleteFromBlob = async function (account, accountKey, containerName, blobFolder, blobName) {
try {
const {
BlobServiceClient,
StorageSharedKeyCredential
} = require("#azure/storage-blob");
const sharedKeyCredential = new StorageSharedKeyCredential(account, accountKey);
const blobServiceClient = new BlobServiceClient(
`https://${account}.blob.core.windows.net`,
sharedKeyCredential
);
const containerClient = blobServiceClient.getContainerClient(containerName);
const blockBlobClient = containerClient.getBlockBlobClient(blobFolder + '/' + blobName);
const uploadblobResponse = await blockBlobClient.deleteIfExists()
return true
}
catch(e) {
return false
}
}
And this works perfect when I know the file name and extension I want to delete, like "2448.pdf":
let deleteFile = await utils.deleteFromBlob(account, accountKey, "agents", "/eopolicies/", userData.agentid.toString() + ".pdf" )
But the problem Im facing is that the function above is to delete a file I know exists; for example, if the agent ID is 2448 and he uploads "policy.pdf" I save it as "2448.pdf" for easy file identification.
The problem Im facing is if the agent uploaded a .PNG last year. a .DOC a year before, and a .PDF now. If that's the case, I want to delete 2448.* and keep only the latest version of the document.
So I tried changing my function to
let deleteFile = await utils.deleteFromBlob(account, accountKey, "agents", "/eopolicies/", userData.agentid.toString() + ".*" )
And of course it is not working...
I tried to find a solution and all I found is one to list the content of a folder, then loop it and delete the specific file I want; but that will not work for me since there are 37,000 EO policies on that folder.
Is there a way to delete files with a specific name, and whatever extension?
Thanks.
I've never tried using a wildcard on the extension side of the file name. However, I would iterate through the files in the directory and find the one that contains the specific string you are looking for. Get it's index, and delete from there.
I am trying to call an API, loop through an array of images, assign unique names to each image in the array and then write them to a local directory. If I simplify the code I can write them to the root folder .I already created the sub folder manually, so it existed prior to running the function.
Here is my basic function:
const imageFolder = './img';
function downloadImage(url, filepath) {
client.get(url, res => {
res.pipe(fs.createWriteStream(`${imageFolder}/${filepath}`));
});
}
...make api call
const imagesArray = generations.data.map(item => item.generation.image_path);
imagesArray.forEach(item => {
// const fileName = uuid.v4() + '.webp'; // trying to assign unique filename with uuid
const fileName = new Date().getTime().toString() + '.webp'; // trying to assign unique filename with date object
downloadImage(item, fileName);
});
If I change
res.pipe(fs.createWriteStream(`${imageFolder}/${filepath}`));
to
res.pipe(fs.createWriteStream(filepath));
then it will work but just dumps the images in the root. I was thinking perhaps I was trying to concatenate a variable name with a string (for fileName + '.webp', but it is working in the root as mentioned. See attached image.
I also tried adding the path into the actual function call inside the forEach loop like so
downloadImage(item, `${imageFolder}/${fileName}`);
I did wonder about needing the __dirname variable, or whether it could be a permissions issue, but I don't see any errors.
I am assuming this is pretty straightforward.
OK, was fairly simple and I guess I sort of knew it once I got it working, changing to
downloadImage(item, path.join('src', 'img', fileName));
path.join concatenates folder names and fixes issues when working across platforms (OSX, Windows etc) which applies in this case as I am testing from both Windows and Mac.
I'm starting to learn Django and one of the projects I have chosen for myself is one that has an HTML front page, in which the user inputs some search text and then that calls to an API using Python and Pytrends, then its saves that information as a CSV file.
I'm having a hard time with the next part which is importing that CSV file into another HTML page, where I would like to use my chart.js file to turn it into a graph. I can't figure out how to open up the file and run it inside of javascript. I have tried a static load but it's not opening up the file, just the path to the file. Please let me know if you need to see any other files or know anything else.
async function getData() {
const data = '{% static "interest.csv" %}';
console.log(data.text());
const table = data.split("\n").slice(1);
table.forEach((row) => {
const columns = row.split(",");
const year = columns[0];
const interest = columns[1];
xlabel.push(year);
console.log(year, interest);
});
Over the years on snapchat I have saved lots of photos that I would like to retrieve now, The problem is they do not make it easy to export, but luckily if you go online you can request all the data (thats great)
I can see all my photos download link and using the local HTML file if I click download it starts downloading.
Here's where the tricky part is, I have around 15,000 downloads I need to do and manually clicking each individual one will take ages, I've tried extracting all of the links through the download button and this creates lots of Urls (Great) but the problem is, if you past the url into the browser then ("Error: HTTP method GET is not supported by this URL") appears.
I've tried a multitude of different chrome extensions and none of them show the actually download, just the HTML which is on the left-hand side.
The download button is a clickable link that just starts the download in the tab. It belongs under Href A
I'm trying to figure out what the best way of bulk downloading each of these individual files is.
So, I just watched their code by downloading my own memories. They use a custom JavaScript function to download your data (a POST request with ID's in the body).
You can replicate this request, but you can also just use their method.
Open your console and use downloadMemories(<url>)
Or if you don't have the urls you can retrieve them yourself:
var links = document.getElementsByTagName("table")[0].getElementsByTagName("a");
eval(links[0].href);
UPDATE
I made a script for this:
https://github.com/ToTheMax/Snapchat-All-Memories-Downloader
Using the .json file you can download them one by one with python:
req = requests.post(url, allow_redirects=True)
response = req.text
file = requests.get(response)
Then get the correct extension and the date:
day = date.split(" ")[0]
time = date.split(" ")[1].replace(':', '-')
filename = f'memories/{day}_{time}.mp4' if type == 'VIDEO' else f'memories/{day}_{time}.jpg'
And then write it to file:
with open(filename, 'wb') as f:
f.write(file.content)
I've made a bot to download all memories.
You can download it here
It doesn't require any additional installation, just place the memories_history.json file in the same directory and run it. It skips the files that have already been downloaded.
Short answer
Download a desktop application that automates this process.
Visit downloadmysnapchatmemories.com to download the app. You can watch this tutorial guiding you through the entire process.
In short, the app reads the memories_history.json file provided by Snapchat and downloads each of the memories to your computer.
App source code
Long answer (How the app described above works)
We can iterate over each of the memories within the memories_history.json file found in your data download from Snapchat.
For each memory, we make a POST request to the URL stored as the memories Download Link. The response will be a URL to the file itself.
Then, we can make a GET request to the returned URL to retrieve the file.
Example
Here is a simplified example of fetching and downloading a single memory using NodeJS:
Let's say we have the following memory stored in fakeMemory.json:
{
"Date": "2022-01-26 12:00:00 UTC",
"Media Type": "Image",
"Download Link": "https://app.snapchat.com/..."
}
We can do the following:
// import required libraries
const fetch = require('node-fetch'); // Needed for making fetch requests
const fs = require('fs'); // Needed for writing to filesystem
const memory = JSON.parse(fs.readFileSync('fakeMemory.json'));
const response = await fetch(memory['Download Link'], { method: 'POST' });
const url = await response.text(); // returns URL to file
// We can now use the `url` to download the file.
const download = await fetch(url, { method: 'GET' });
const fileName = 'memory.jpg'; // file name we want this saved as
const fileData = download.body; // contents of the file
// Write the contents of the file to this computer using Node's file system
const fileStream = fs.createWriteStream(fileName);
fileData.pipe(fileStream);
fileStream.on('finish', () => {
console.log('memory successfully downloaded as memory.jpg');
});
I am trying to import a file , where the part of the file name get changes very frequently. Current date is the part of the file name. so it get changes very frequently.
Below is my code the import the file. since its name changes
How do I import the file without changing the file name every day ?
var CusInfo = path.join(__dirname,'
CusInfo_2018_05-17.txt');
Here is an example of where we use the fs library to read the contents of a directory and search for files containing 'CusInfo'.
import fs from 'fs';
let contents = fs.readDirSync('./foo');
for(let x = 0; x < contents.length; x++){
if(contents[x].includes('CusInfo')){
// Do more checks or use the file or save to another variable.
}
}
Now if the file name changes because of the date you can still find the file or files.
Given that the name of the file you want to read changes every day, you need to describe the same naming rules in your code, if you don't want hardcode the name.
Since (I'm assuming) you just want today's data to be in the path of the txt file, just put that into the file name. You can do that with moment like so:
const moment = require('moment');
const fs = require('fs');
const now = moment();
const fileName = `CusInfo_${now.format('YYYY_MM-DD')}.txt`;
fs.readFileSync(fileName);
Now this might very well throw an error, because there is no guarantee that the txt file have been created yet.
To handle this, use fs.access() before actually reading the file
fs.access(fileName, fs.constants.F_OK, (err) => {
if (err) {
fileName = `CusInfo_${now.add(-1, 'days').format('YYYY_MM-DD')}.txt`;
}
fs.readFileSync(fileName)
}
This code above will check if the txt file for today exsists, and if not, will change the file name yesterday txtfile.