Rubik-file NPM

rubik-file

File storage Kubik, for Rubik's applications

Using example

This module is designed to be used with rubik-main.

const { App, Kubiks } = require('rubik-main');
const File = require('rubik-file');
const FileFS = require('rubik-file-fs');

// Creating application instance
const app = new App();
// Creating config kubik, add path to the config directory
// Config kubik is a depedency of File kubik
const config = new Kubiks.Config(path.join(__dirname, '../config/'));
// Creating file kubik
const file = new File({
  provider: 'FS',
  bucket: 'main'
});

// Add filesystem provider constructor
File.addProvider('FS', FileFS);

app.add([config, file]);

app.up().
then(async () => {
  console.info('Application started');

  const rs = fs.createReadStream(path.join(__dirname, './in/file.txt'));

  // Write to the storage
  await app.file.write({ key: 'some-file.txt' }, rs);
  // Read from the storage
  const stream = await app.file.read({ key: 'some-file.txt' });

  const ws = fs.createWriteStream(path.join(__dirname, './out/file.txt'));
  stream.pipe(ws);
}).
catch((err) => {
  console.error(err);
  process.exit(1);
});

Providers

To make it easier to extend File kubik with different storages, the logic for working with them must be placed in classes called Providers.

A provider is a Class-child of the Provider class. The Provider should has an implementation of the write,has, read, andremove methods. Optionally, there may also be a copy method - for copying files inside storage.

Source

I will use this type bellow for some methods' arguments and params

Basically it is an Object with two keys:

key is an file identifier inside storage
bucket is an abstraction of Drive in some kind of storages

More about keys and buckets you can read in the AWS documentation.

Implementing of methods

write(to, readableStream)

Writes stream to a storage

There two required arguments:

to is a Source object, key and bucket inside storage for new file
readableStream is a Readable Stream

It should return Promise (or be async) that resolves nothing If an error occurs, an exception must be thrown.

has(source)

Checks file in the storage

There only one required argument:

source is a Source object, key and bucket inside storage

It should return Promise (or be async) that resolves Boolean,

true, when file exists;
false, when file does not exists;

If an error occurs, an exception must be thrown.

read(from)

Reads file from the storage

There only one required argument:

from is a Source object, key and bucket inside storage

It should return Promise (or be async) that resolves Readable Stream,

If an error occurs, an exception must be thrown.

remove(source)

Removes file from the storage

There only one required argument:

source is a Source object, key and bucket inside storage

It should return Promise (or be async) that resolves nothing

If an error occurs, an exception must be thrown.

copy(from, to) — optional method

Copies file from one destination to other. Inside the storage. It is an optional method. If it is not exists, File kubik just calls read(from) and write(to, streamFrom).

There two required arguments:

from is a Source object, key and bucket inside storage for existing file
to is a Source object, key and bucket inside storage for new file

It should return Promise (or be async) that resolves nothing If an error occurs, an exception must be thrown.