I have a chrome extension that saves a bunch of data to chrome.storage.local. I'm trying to find easy ways to export this data and package it into a file. I'm not constrained on what type of file it is (JSON, CSV, whatever), I just need to be able to export the contents into a standalone (and send-able) file. The extension is only run locally and the user would have access to all local files.
First, you need to get all data.
Then serialize the result.
Finally, offer it as a download to the user.
chrome.storage.local.get(null, function(items) { // null implies all items
// Convert object to a string.
var result = JSON.stringify(items);
// Save as file
var url = 'data:application/json;base64,' + btoa(result);
chrome.downloads.download({
url: url,
filename: 'filename_of_exported_file.json'
});
});
To use the chrome.downloads.download method, you need to declare the "downloads" permission in addition to the storage permission in the manifest file.
You should look here: https://groups.google.com/a/chromium.org/forum/#!topic/chromium-extensions/AzO_taH2b7U
It shows exporting chrome local storage to JSON.
Hope it helps
Related
I am using the One Drive API to grab a file with a node application using the axios library.
I am simply trying to save the file to the local machine (node is running locally).
I use the One Drive API to get the download document link, which does not require authentication (with https://graph.microsoft.com/v1.0/me/drives/[location]/items/[id]).
Then I make this call with the download document link:
response = await axios.get(url);
I receive a JSON response, which includes, among other things, the content-type, content-length, content-disposition and a data element which is the contents of the file.
When I display the JSON response to the console, the data portion looks like this:
data: 'PK\u0003\u0004\u0014\u0000\u0006\u0000\b\u0000\u0000\u0000!\u...'
If the document is simply text, I can save it easily using:
fs.writeFileSync([path], response.data);
But if the file is binary, like a docx file, I cannot figure out how to write it properly. Every time I try it seems to have the wrong encoding. I tried different encodings.
How do I save the file properly based on the type of file retrieved.
Have you tried using an encoding option of fs.writeFileSync of explicitly null, signifying the data is binary?
fs.writeFileSync([path], response.data, {
encoding: null
});
I set up my discord BOT using node.js. For my advantage, I would need to store some data on a external file, but I don't seem to be able to access it from my index.js file (the main Bot file).
I've tried having one static array in the external js/json files, but I can only retrieve undefined/empty values. Additionally, when I tried with a .txt file, once retrieved the content, I found it unable to call functions such as string.split().
Did I miss something in the package content perhaps?
Assuming the data you are storing is in UTF-8 encoding:
var fs = require('fs');
fs.readFile('path/to/file', 'utf8', function(err, contents) {
// code using file data
});
Assuming no errors contents will be a string of the data that is inside that file.
https://code-maven.com/reading-a-file-with-nodejs
I'm trying to save a remote image file into a database, but I'm having some issues with it since I've never done it before.
I need to download the image and pass it along (with node-request) with a few other properties to another node api that saves it into a mysql database (using sequelize). I've managed to get some data to save, but when I download it manually and try to open it, it's not really usable and no image shows up.
I've tried a few things: getting the image with node-request, converting it to a base64 string (read about that somewhere) and passing it along in a json payload, but that didn't work. Tried sending it as a multipart, but that didn't work either. Haven't worked with streams/buffers/multipart all that much before and never in node. I've tried looking into node-request pipes, but I couldn't really figure out how possibly apply them to this context.
Here's what I currently have (it's a part es6 class so there's no 'function' keywords; also, request is promisified):
function getImageData(imageUrl) {
return request({
url: imageUrl,
encoding: null,
json: false
});
}
function createEntry(entry) {
return getImageData(entry.image)
.then((imageData) => {
entry.image_src = imageData.toString('base64');
var requestObject = {
url: 'http://localhost:3000/api/entry',
method: 'post',
json: false,
formData: entry
};
return request(requestObject);
});
}
I'm almost 100% certain the problem is in this part because the api just takes what it gets and gives it to sequelize to put into the table, but I could be wrong. Image field is set as longblob.
I'm sure it's something simple once I figure it out, but so far I'm stumped.
This is not a direct answer to your question but it is rarely needed to actually store an image in the database. What is usually done is storing an image on storage like S3, a CDN like CloudFront or even just in a file system of a static file server, and then storing only the file name or some ID of the image in the actual database.
If there is any chance that you are going to serve those images to some clients then serving them from the database instead of a CDN or file system will be very inefficient. If you're not going to serve those images then there is still very little reason to actually put them in the database. It's not like you're going to query the database for specific contents of the image or sort the results on the particular serialization of an image format that you use.
The simplest thing you can do is save the images with a unique filename (either a random string, UUID or a key from your database) and keep the ID or filename in the database with other data that you need. If you need to serve it efficiently then consider using S3 or some CDN for that.
I'm a front-end dev just venturing into the Node.js, particularly in using it to create small command line tools.
My question: how do you persist data with command line tools? For example, if I want to keep track of the size of certain files over time, I'd need to keep a running record of changes (additions and deletions) to those files, and relevant date/time information.
On the web, you store that sort of data in a database on a server, and then query the database when you need it again. But how do you do it when you're creating a Node module that's meant to be used as a command line tool?
Some generic direction is all I'm after. I don't even know what to Google at this point.
It really depends on what you're doing, but a simple approach is to just save the data that you want to persist to a file and, since we're talking node, store it in JSON format.
Let's say you have some data like:
var data = [ { file: 'foo.bar', size: 1234, date: '2014-07-31 00:00:00.000'}, ...]
(it actually doesn't matter what it is, as long as it can be JSON.stringifiy()d)
You can just save it with:
fs.writeFile(filename, JSON.stringify(data), {encoding: 'utf8'}, function(err) { ... });
And load it again with:
fs.readFile(filename, {encoding: 'utf8'}, function(err, contents) {
data = JSON.parse(contents);
});
You'll probably want to give the user the ability to specify the name of the file you're going to persist the data to via an argument like:
node myscript.js <data_file>
You can get that passed in parameter with process.argv:
var filename = process.argv[2]; // Be sure to check process.argv.length and have a default
Using something like minimist can be really helpful if you want to get more complex like:
node myscript.js --output <data_file>
You also can store files in temporary directory, for example /tmp directory on linux and give user the option to change the directory.
To get path to temporary directory you can use os module in nodejs:
const os = require('os');
const tmp = os.tmpdir();
I am using Web activity to launch default Firefox camera from my web app in Firefox OS. Able to launch default Firefox camera and took picture. Got this.result as return value inside pick success.
Now I need to get file path, where image get saved and also image file name.
Tried to parse the this.result.blob, but couldn't find the path or file related parameter .
Below is the code I'm using
var activity = new MozActivity({
// Ask for the "pick" activity
name: "pick",
// Provide the data required by the filters of the activity
data: {
type: "image/jpeg"
}
});
activity.onsuccess = function() {
var picture = this.result;
console.log("A picture has been retrieved");
};
The image file name is not returned, as you can see from the code. If you would need the file name (I can't really think of a very good use case to be honest) you can iterate over the pictures storage in the DeviceStorageAPI and get the last saved file. It's probably the one from the camera (compare blobs to be totally sure).
In your success handler, you will get the file name if you use:
this.result.blob.name
And, you can get the path to the file as:
window.URL.createObjectURL(this.result.blob);
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