Skip to main content

File API (Object Store)

File API provides an interface-like object store for you to upload files and streams (eg. photos, videos or any type of document) and efficiently retrieve them for use in your web/mobile DApp.

File protocol is based on object stores. When you upload something, a CID is created and returned to you and the file gets stored in an IPFS compatible datastore.

Upload​

SendFile​

sendFile(File) => Promise<FileId>

sendFile will take a File as an argument and return a Promise. If the upload completes successfully, a Promise will return a FileId that is a string representing the CID of uploaded content.

Example​

import {Fula, createClient} from '@functionland/fula';

const fulaClient = await createClient();
await fulaClient.connect(serverId);
...
const selectedFile = document.getElementById('input').files[0];
const id = await fulaClient.sendFile(selectedFile);

sendStreamFile​

sendStreamFile(source, meta) => Promise<FileId>

sendStreamFile will take a source and meta as argument and return a Promise. If upload is done successfully, a Promise will return a FileId that is a string representing the CID of uploaded content. (This is useful when you're working with stream or outside the browser.)

  • source: AsyncIterable<Uint8Array>
  • meta: {name,type,lastModified,size}

Example​

import {Fula, createClient} from '@functionland/fula';

const fulaClient = await createClient();
await fulaClient.connect(serverId);
...
export async function* fileToAsyncItrable(file:File) {
    const reader = (file.stream()).getReader();
    while (true) {
        const {value, done} = await reader.read();
        if (done) {
            break;
        }
        yield value;
    }
}
const selectedFile = document.getElementById('input').files[0];
const id = await fulaClient.sendStreamFile(fileToAsyncItrable(selectedFile),
    {
        name: selectedFile.name,
        type: selectedFile.type,
        size: selectedFile.size,
        lastModified: selectedFile.lastModified
    });

Download​

receiveFile​

(fileId: FileId) => Promise<File>

receiveFile will take FileId and return Promise. if file retrieved successfully Promise return a File

  • fileId: FileId

Example​

import {Fula, createClient} from '@functionland/fula';

const fulaClient = await createClient();
await fulaClient.connect(serverId);
...
const data = await fulaClient.receiveFile(fileId);

receiveMeta​

(fileId: FileId) => Promise<Meta>

receiveMeta will take FileId and return Promise. if meta for the file retrieved successfully Promise return a Meta

  • fileId: FileId

Example​

import {Fula, createClient} from '@functionland/fula';

const fulaClient = await createClient();
await fulaClient.connect(serverId);
...
const {name, type, size, lastModified} = await fulaClient.receiveMeta(fileId);

receiveStreamFile​

(fileId: FileId) => Promise<{ source: AsyncIterable<Uint8Array>, meta: Meta }>

receiveStreamFile will take FileId and return a Promise. If the FileId exists, a Promise will return a { source: AsyncIterable<Uint8Array>, meta: Meta }

That source is a stream of content of the file and Meta is the Meta. (This is useful when you're working with a stream or outside of the browser.)

  • fileId: FileId

Example​

import {Fula, createClient} from '@functionland/fula';

const fulaClient = await createClient();
await fulaClient.connect(serverId);
...
const {source, meta} = await fulaClient.receiveStreamFile(fileId);
const {name, type, size, lastModified} = meta;
const content: Array<Uint8Array> = [];
for await (const chunk of source) {
    content.push(Uint8Array.from(chunk));
}
const blob = new Blob(content, {type})


WIP Alert

Please note: these instructions remain a work in progress as we continue to evolve, refine and perfect the Fula API. Make sure to check back soon for more details!