/*
This is a shim to the IPFS library, (Lists are handled in YJS or OrbitDB)
See https://github.com/ipfs/js-ipfs but note its often out of date relative to the generic API doc.
*/
const httptools = require('./httptools'); // Expose some of the httptools so that IPFS can use it as a backup
const debug = require('debug')('dweb-transports:ipfs');
// IPFS components
const IPFS = require('ipfs');
const ipfsAPI = require('ipfs-api');
const CID = require('cids');
//Removed next two as not needed if use "Kludge" flagged below.
//const dagPB = require('ipld-dag-pb');
//const DAGNode = dagPB.DAGNode; // So can check its type
const unixFs = require('ipfs-unixfs');
// Library packages other than IPFS
const Url = require('url');
const stream = require('readable-stream'); // Needed for the pullthrough - this is NOT Ipfs streams
// Alternative to through - as used in WebTorrent
// Utility packages (ours) And one-liners
//No longer reqd: const promisify = require('promisify-es6');
//const makepromises = require('./utils/makepromises'); // Replaced by direct call to promisify
// Other Dweb modules
const errors = require('./Errors'); // Standard Dweb Errors
const Transport = require('./Transport.js'); // Base class for TransportXyz
const Transports = require('./Transports'); // Manage all Transports that are loaded
const utils = require('./utils'); // Utility functions
const defaultoptions = {
repo: '/tmp/dweb_ipfsv2700', //TODO-IPFS think through where, esp for browser
//init: false,
//start: false,
//TODO-IPFS-Q how is this decentralized - can it run offline? Does it depend on star-signal.cloud.ipfs.team
config: {
// Addresses: { Swarm: [ '/dns4/star-signal.cloud.ipfs.team/wss/p2p-webrtc-star']}, // For Y - same as defaults
// Addresses: { Swarm: [ ] }, // Disable WebRTC to test browser crash, note disables Y so doesnt work.
//Addresses: {Swarm: ['/dns4/ws-star.discovery.libp2p.io/tcp/443/wss/p2p-websocket-star']}, // from https://github.com/ipfs/js-ipfs#faq 2017-12-05 as alternative to webrtc works sort-of
Bootstrap: ['/dns4/dweb.me/tcp/4245/wss/ipfs/QmPNgKEjC7wkpu3aHUzKKhZmbEfiGzL5TP1L8zZoHJyXZW'], // Connect via WSS to IPFS instance at IA
},
//init: true, // Comment out for Y
EXPERIMENTAL: {
pubsub: true
}
};
class TransportIPFS extends Transport {
/*
IPFS specific transport
Fields:
ipfs: object returned when starting IPFS
TODO - this is not complete
*/
constructor(options) {
super(options);
this.ipfs = undefined; // Undefined till start IPFS
this.options = options; // Dictionary of options
this.name = "IPFS"; // For console log etc
this.supportURLs = ['ipfs'];
this.supportFunctions = ['fetch', 'store', 'createReadStream']; // Does not support reverse
this.status = Transport.STATUS_LOADED;
}
_ipfsversion(ipfs, s, cb) {
ipfs.version((err, data) => {
if (err) {
debug("IPFS via %s present but unresponsive: %o", s, data);
cb(err);
} else {
debug("IPFS available via %s: %o", s, data);
cb(null, ipfs);
}
});
}
IPFSAutoConnect(cb) {
if (global.ipfs) {
this._ipfsversion(global.ipfs, "global.ipfs", cb );
} else if (typeof window !== "undefined" && window.ipfs) {
this._ipfsversion(window.ipfs, "window.ipfs", cb );
} else {
// noinspection ES6ConvertVarToLetConst
var ipfs = ipfsAPI('localhost', '5001', {protocol: 'http'}); // leaving out the arguments will default to these values
ipfs.version((err, data) => {
if (err) {
debug("IPFS via API failed %s, trying running own IPFS client", err.message);
ipfs = new IPFS(this.options);
ipfs.on('ready', () => {
this._ipfsversion(ipfs, "client", cb);
}); // This only works in the client version, not on API
ipfs.on('error', (err) => {
debug("IPFS via client error %s", err.message); // Calls error, note this could be a problem if it gets errors after "ready"
cb(err);
}) // This only works in the client version, not on API
} else {
this._ipfsversion(ipfs, "API", cb); // Note wastes an extra ipfs.version call but that's cheap
}
});
}
}
/*OBS
p_ipfsstart() {
/-*
Just start IPFS - not Y (note used with "yarrays" and will be used for non-IPFS list management)
Note - can't figure out how to use async with this, as we resolve the promise based on the event callback
*-/
const self = this;
return new Promise((resolve, reject) => {
this.ipfs = new IPFS(this.options);
this.ipfs.on('ready', () => {
//this._makepromises();
resolve();
});
this.ipfs.on('error', (err) => reject(err));
})
.then(() => self.ipfs.version())
.then((version) => debug('ready %o',version))
.catch((err) => {
console.warn("IPFS p_ipfsstart failed", err.message);
throw(err);
});
}
*/
static setup0(options) {
/*
First part of setup, create obj, add to Transports but dont attempt to connect, typically called instead of p_setup if want to parallelize connections.
*/
const combinedoptions = Transport.mergeoptions(defaultoptions, options.ipfs);
debug("setup options=%o", combinedoptions);
const t = new TransportIPFS(combinedoptions); // Note doesnt start IPFS
Transports.addtransport(t);
return t;
}
async p_setup1(cb) {
// cb is function for updating status, it must be ale to be called multiple times.
try {
// Logged by Transports
this.status = Transport.STATUS_STARTING; // Should display, but probably not refreshed in most case
if (cb) cb(this);
this.ipfs = await new Promise((resolve, reject) => {
this.IPFSAutoConnect((err, data) => {
if (err) { reject(err); } else { resolve(data); } // Various errors possible inc websocket
})
});
this.status = Transport.STATUS_CONNECTED; // p_status doesnt work on HTTP API - errors should be caught below anyway. await this.p_status();
} catch(err) {
// Logged by Transports
console.error(this.name, "failed to connect", err);
this.status = Transport.STATUS_FAILED;
// Dont throw an error, allow other transports to complete setup
}
if (cb) cb(this);
return this;
}
async p_status() {
/*
Return a numeric code for the status of a transport.
TODO - this no longer works if using the http api
*/
this.status = (await this.ipfs.isOnline()) ? Transport.STATUS_CONNECTED : Transport.STATUS_FAILED;
return super.p_status();
}
// Everything else - unless documented here - should be opaque to the actual structure of a CID
// or a url. This code may change as its not clear (from IPFS docs) if this is the right mapping.
static urlFrom(unknown) {
/*
Convert a CID into a standardised URL e.g. ipfs:/ipfs/abc123
*/
if (unknown instanceof CID)
return "ipfs:/ipfs/"+unknown.toBaseEncodedString();
if (typeof unknown === "object" && unknown.hash) // e.g. from files.add
return "ipfs:/ipfs/"+unknown.hash;
if (typeof unknown === "string") // Not used currently
return "ipfs:/ipfs/"+unknown;
throw new errors.CodingError("TransportIPFS.urlFrom: Cant convert to url from",unknown);
}
static cidFrom(url) {
/*
Convert a URL e.g. ipfs:/ipfs/abc123 into a CID structure suitable for retrieval
url: String of form "ipfs://ipfs/<hash>" or parsed URL or CID
returns: CID
throws: TransportError if cant convert
*/
if (url instanceof CID) return url;
if (typeof(url) === "string") url = Url.parse(url);
if (url && url["pathname"]) { // On browser "instanceof Url" isn't valid)
const patharr = url.pathname.split('/');
if ((!["ipfs:","dweb:"].includes(url.protocol)) || (patharr[1] !== 'ipfs') || (patharr.length < 3))
throw new errors.TransportError("TransportIPFS.cidFrom bad format for url should be dweb: or ipfs:/ipfs/...: " + url.href);
if (patharr.length > 3)
throw new errors.TransportError("TransportIPFS.cidFrom not supporting paths in url yet, should be dweb: or ipfs:/ipfs/...: " + url.href);
return new CID(patharr[2]);
} else {
throw new errors.CodingError("TransportIPFS.cidFrom: Cant convert url", url);
}
}
static _stringFrom(url) {
// Tool for ipfsFrom and ipfsGatewayFrom
if (url instanceof CID)
return "/ipfs/"+url.toBaseEncodedString();
if (typeof url === 'object' && url.path) { // It better be URL which unfortunately is hard to test
return url.path;
}
}
static ipfsFrom(url) {
/*
Convert to a ipfspath i.e. /ipfs/Qm....
Required because of strange differences in APIs between files.cat and dag.get see https://github.com/ipfs/js-ipfs/issues/1229
*/
url = this._stringFrom(url); // Convert CID or Url to a string hopefully containing /ipfs/
if (url.indexOf('/ipfs/') > -1) {
return url.slice(url.indexOf('/ipfs/'));
}
throw new errors.CodingError(`TransportIPFS.ipfsFrom: Cant convert url ${url} into a path starting /ipfs/`);
}
static ipfsGatewayFrom(url) {
/*
url: CID, Url, or a string
returns: https://ipfs.io/ipfs/<cid>
*/
url = this._stringFrom(url); // Convert CID or Url to a string hopefully containing /ipfs/
if (url.indexOf('/ipfs/') > -1) {
return "https://ipfs.io" + url.slice(url.indexOf('/ipfs/'));
}
throw new errors.CodingError(`TransportIPFS.ipfsGatewayFrom: Cant convert url ${url} into a path starting /ipfs/`);
}
static multihashFrom(url) {
if (url instanceof CID)
return url.toBaseEncodedString();
if (typeof url === 'object' && url.path)
url = url.path; // /ipfs/Q...
if (typeof(url) === "string") {
const idx = url.indexOf("/ipfs/");
if (idx > -1) {
return url.slice(idx+6);
}
}
throw new errors.CodingError(`Cant turn ${url} into a multihash`);
}
// noinspection JSCheckFunctionSignatures
async p_rawfetch(url, {timeoutMS=60000, relay=false}={}) {
/*
Fetch some bytes based on a url of the form ipfs:/ipfs/Qm..... or ipfs:/ipfs/z.... .
No assumption is made about the data in terms of size or structure, nor can we know whether it was created with dag.put or ipfs add or http /api/v0/add/
Where required by the underlying transport it should retrieve a number if its "blocks" and concatenate them.
Returns a new Promise that resolves currently to a string.
There may also be need for a streaming version of this call, at this point undefined since we havent (currently) got a use case..
:param string url: URL of object being retrieved {ipfs|dweb}:/ipfs/<cid> or /
:resolve buffer: Return the object being fetched. (may in the future return a stream and buffer externally)
:throws: TransportError if url invalid - note this happens immediately, not as a catch in the promise
*/
// Attempt logged by Transports
if (!url) throw new errors.CodingError("TransportIPFS.p_rawfetch: requires url");
const cid = TransportIPFS.cidFrom(url); // Throws TransportError if url bad
const ipfspath = TransportIPFS.ipfsFrom(url); // Need because dag.get has different requirement than file.cat
try {
const res = await utils.p_timeout(this.ipfs.dag.get(cid), timeoutMS, "Timed out IPFS fetch of "+TransportIPFS._stringFrom(cid)); // Will reject and throw TimeoutError if times out
// noinspection Annotator
if (res.remainderPath.length)
{ // noinspection ExceptionCaughtLocallyJS
throw new errors.TransportError("Not yet supporting paths in p_rawfetch");
} //TODO-PATH
let buff;
if (res.value.constructor.name === "DAGNode") { // Kludge to replace above, as its not matching the type against the "require" above.
// We retrieved a DAGNode, call files.cat (the node will come from the cache quickly)
buff = await this.ipfs.files.cat(ipfspath); //See js-ipfs v0.27 version and https://github.com/ipfs/js-ipfs/issues/1229 and https://github.com/ipfs/interface-ipfs-core/blob/master/SPEC/FILES.md#cat
} else { //c: not a file
debug("Found a raw IPFS block (unusual) - not a DAGNode - handling as such");
buff = res.value;
}
// Success logged by Transports
return buff;
} catch (err) { // TimeoutError or could be some other error from IPFS etc
debug("Caught error '%s' fetching via IPFS, trying IPFS HTTP gateway", err.message);
try {
let ipfsurl = TransportIPFS.ipfsGatewayFrom(url);
return await utils.p_timeout(
httptools.p_GET(ipfsurl), // Returns a buffer
timeoutMS, "Timed out IPFS fetch of "+ipfsurl)
} catch (err) {
// Failure logged by Transports:
//debug("Failed to retrieve from gateway: %s", err.message);
throw err;
}
}
}
async p_rawstore(data) {
/*
Store a blob of data onto the decentralised transport.
Returns a promise that resolves to the url of the data
:param string|Buffer data: Data to store - no assumptions made to size or content
:resolve string: url of data stored
*/
console.assert(data, "TransportIPFS.p_rawstore: requires data");
const buf = (data instanceof Buffer) ? data : new Buffer(data);
const res = (await this.ipfs.files.add(buf,{ "cid-version": 1, hashAlg: 'sha2-256'}))[0];
return TransportIPFS.urlFrom(res);
}
/* OLD WAY Based on https://github.com/ipfs/js-ipfs/pull/1231/files TODO-IPFS repurpose this to add byte range to new function fetch calling p_rawfetch
async p_offsetStream(stream, links, startByte, endByte) {
let streamPosition = 0
try {
for (let l in links) {
const link = links[l];
if (!stream.writable) { return } // The stream has been closed
// DAGNode Links report unixfs object data sizes 14 bytes larger due to the protobuf wrapper
const bytesInLinkedObjectData = link.size - 14
if (startByte > (streamPosition + bytesInLinkedObjectData)) {
// Start byte is after this block so skip it
streamPosition += bytesInLinkedObjectData;
} else if (endByte && endByte < streamPosition) { // TODO-STREAM this is copied from https://github.com/ipfs/js-ipfs/pull/1231/files but I think it should be endByte <= since endByte is first byte DONT want
// End byte was before this block so skip it
streamPosition += bytesInLinkedObjectData;
} else {
let lmh = link.multihash;
let data;
await this.ipfs.object.data(lmh)
.then ((d) => unixFs.unmarshal(d).data)
.then ((d) => data = d )
.catch((err) => {console.log("XXX@289 err=",err);});
if (!stream.writable) { return; } // The stream was closed while we were getting data
const length = data.length;
if (startByte > streamPosition && startByte < (streamPosition + length)) {
// If the startByte is in the current block, skip to the startByte
data = data.slice(startByte - streamPosition);
}
console.log(`Writing ${data.length} to stream`)
stream.write(data);
streamPosition += length;
}
}
} catch(err) {
console.log(err.message);
}
}
async p_f_createReadStream(url) { // Asynchronously return a function that can be used in createReadStream
if () console.log("p_f_createReadStream", url);
const mh = TransportIPFS.multihashFrom(url);
const links = await this.ipfs.object.links(mh);
let throughstream; //Holds pointer to stream between calls.
const self = this;
function crs(opts) { // This is a synchronous function
// Return a readable stream that provides the bytes between offsets "start" and "end" inclusive
debug("opts=%o", opts);
// Can replace rest of crs with this when https://github.com/ipfs/js-ipfs/pull/1231/files lands (hopefully v0.28.3)
// return self.ipfs.catReadableStream(mh, opts ? opts.start : 0, opts && opts.end) ? opts.end+1 : undefined)
if (!opts) return throughstream; //TODO-STREAM unclear why called without opts - take this out when figured out
if (throughstream && throughstream.destroy) throughstream.destroy();
throughstream = new stream.PassThrough();
self.p_offsetStream( // Ignore promise returned, this will write to the stream asynchronously
throughstream,
links, // Uses the array of links created above in this function
opts ? opts.start : 0,
(opts && opts.end) ? opts.end : undefined);
return throughstream;
}
return crs;
}
*/
async p_f_createReadStream(url, {wanturl=false}={}) {
/*
Fetch bytes progressively, using a node.js readable stream, based on a url of the form:
No assumption is made about the data in terms of size or structure.
This is the initialisation step, which returns a function suitable for <VIDEO>
Returns a new Promise that resolves to function for a node.js readable stream.
Node.js readable stream docs: https://nodejs.org/api/stream.html#stream_readable_streams
:param string url: URL of object being retrieved of form:
magnet:xyzabc/path/to/file (Where xyzabc is the typical magnet uri contents)
ipfs:/ipfs/Q123
:resolves to: f({start, end}) => stream (The readable stream.)
:throws: TransportError if url invalid - note this happens immediately, not as a catch in the promise
*/
// Logged by Transports;
//debug("p_f_createreadstream %o", url);
let stream;
try {
let multihash = url.pathname.split('/ipfs/')[1];
if (multihash.includes('/'))
{ // noinspection ExceptionCaughtLocallyJS
throw new CodingError("Should not be seeing URLS with a path here:"+url);
}
let self = this;
if (wanturl) { // In ServiceWorker
return url;
} else {
return function createReadStream(opts) {
/*
The function, encapsulated and inside another function by p_f_createReadStream (see docs)
:param opts: { start: byte to start from; end: optional end byte }
:returns stream: The readable stream.
FOR IPFS this is copied and adapted from git repo js-ipfs/examples/browser-readablestream/index.js
*/
debug("reading from stream %o %o", multihash, opts || "" );
const start = opts ? opts.start : 0;
// The videostream library does not always pass an end byte but when
// it does, it wants bytes between start & end inclusive.
// catReadableStream returns the bytes exclusive so increment the end
// byte if it's been requested
const end = (opts && opts.end) ? start + opts.end + 1 : undefined;
// If we've streamed before, clean up the existing stream
if (stream && stream.destroy) {
stream.destroy()
}
// This stream will contain the requested bytes
// For debugging used a known good IPFS video
//let fakehash="QmedXJYwvNSJFRMVFuJt7BfCMcJwPoqJgqN3U2MYxHET5a"
//console.log("XXX@IPFS.p_f_createReadStream faking call to",multihash, "with", fakehash)
//multihash=fakehash;
stream = self.ipfs.files.catReadableStream(multihash, {
offset: start,
length: end && end - start
});
// Log error messages
stream.on('error', (err) => console.error(err));
/* Gimmick from example :-)
if (start === 0) {
// Show the user some messages while we wait for the data stream to start
statusMessages(stream, log)
}
*/
return stream
};
}
} catch(err) {
if (stream && stream.destroy) {
stream.destroy()
}
// Error logged by Transports
//console.log(`p_f_createReadStream failed on ${url} ${err.message}`);
throw(err);
}
}
static async p_test(opts) {
{console.log("TransportIPFS.test")}
try {
const transport = await this.p_setup(opts); // Assumes IPFS already setup
console.log(transport.name,"setup");
const res = await transport.p_status();
console.assert(res === Transport.STATUS_CONNECTED);
let urlqbf;
const qbf = "The quick brown fox";
const qbf_url = "ipfs:/ipfs/zdpuAscRnisRkYnEyJAp1LydQ3po25rCEDPPEDMymYRfN1yPK"; // Expected url
const testurl = "1114"; // Just a predictable number can work with
const url = await transport.p_rawstore(qbf);
console.log("rawstore returned", url);
const newcid = TransportIPFS.cidFrom(url); // Its a CID which has a buffer in it
console.assert(url === qbf_url, "url should match url from rawstore");
const cidmultihash = url.split('/')[2]; // Store cid from first block in form of multihash
const newurl = TransportIPFS.urlFrom(newcid);
console.assert(url === newurl, "Should round trip");
urlqbf = url;
const data = await transport.p_rawfetch(urlqbf);
console.assert(data.toString() === qbf, "Should fetch block stored above");
//console.log("TransportIPFS test complete");
return transport
} catch(err) {
console.log("Exception thrown in TransportIPFS.test:", err.message);
throw err;
}
}
}
Transports._transportclasses["IPFS"] = TransportIPFS;
// noinspection JSUndefinedPropertyAssignment
exports = module.exports = TransportIPFS;