Add Bitfinex backend

lib/HttpLightningBackend.js

@@ -19,7 +19,7 @@ class HttpLightningBackend extends LightningBackend {
 		assert.ok(options.baseUrl || (options.hostname && options.protocol), 'Missing required option(s): Must provide either "baseUrl" or "hostname" and "protocol"');
 	}
 
-	request(method, uri, data) {
+	request(method, uri, data, extraHeaders = {}) {
 		return Promise.resolve().then(() => {
 			const { name } = this;
 			data = data || {};
@@ -37,12 +37,14 @@ class HttpLightningBackend extends LightningBackend {
 			}
 			const requestUrl = `${baseUrl}${uri}`;
 			const parsedUrl = url.parse(requestUrl);
+			const finalHeaders = Object.assign(Object.assign({}, headers), extraHeaders);
 			let options = {
 				method: method.toUpperCase(),
 				hostname: parsedUrl.hostname,
 				port: parsedUrl.port,
 				path: parsedUrl.path,
-				headers: Object.assign({}, headers),
+				 // extraHeaders are specific to a single request, and therefore should not be set on the class-scope "options" object.
+				headers: finalHeaders,
 			};
 			if (cert) {
 				options.ca = cert;

lib/backends/bitfinex.js

@@ -0,0 +1,144 @@
+const assert = require('assert');
+const crypto = require('crypto');
+const HttpLightningBackend = require('../HttpLightningBackend');
+
+class Backend extends HttpLightningBackend {
+
+    static name = 'bitfinex';
+
+    constructor(options) {
+        options = options || {};
+        super(Backend.name, options, {
+            defaultOptions: {
+                apiKey: null,
+                apiSecret: null,
+                baseUrl: null,
+                callbackUrl: null,
+                // Production => api.bitfinex.com
+                hostname: 'api.bitfinex.com',
+                protocol: 'https',
+                requestContentType: 'json',
+            },
+            requiredOptions: ['apiKey', 'apiSecret'],
+        });
+        // Headers bfx-nonce and bfx-signature are also required, but must be added individually on each request.
+        this.options.headers['bfx-apikey'] = this.options.apiKey;
+
+        // Bitfinex requires that this must be called once on the account before invoices can be generated.
+        const path = 'v2/auth/w/deposit/address';
+        let postData = {
+            wallet: 'exchange',
+            method: 'LNX',
+        };
+        const extraHeaders = this.generateAuthHeaders(path, postData, this.options.apiSecret)
+        this.request('post', `/${path}`, postData, extraHeaders).then(result => {
+            assert.ok(result && result.length === 8, `Unexpected response from LN Backend [POST ${path}]: data length should be 8 but is ${result.length}`);
+            const status = result[6];
+            assert.ok(status === 'SUCCESS')
+        });
+    }
+
+    checkOptions(options) {
+        assert.strictEqual(typeof options.apiKey, 'string', 'Invalid option ("apiKey"): String expected');
+        assert.strictEqual(typeof options.apiSecret, 'string', 'Invalid option ("apiSecret"): String expected');
+        HttpLightningBackend.prototype.checkOptions.call(this, options);
+    }
+
+    // https://docs.bitfinex.com/reference/rest-auth-deposit-invoice
+    payInvoice(invoice) {
+        return Promise.reject(new Error('Not supported by this LN service.'));
+    }
+
+    // https://docs.bitfinex.com/reference/rest-auth-deposit-invoice
+    addInvoice(amount, extra) {
+        const path = 'v2/auth/w/deposit/invoice';
+        let postData = {
+            wallet: 'exchange',
+            currency: 'LNX',
+            amount: (amount * 1.0 / 100000000000).toFixed(8) // Convert msats to BTC.
+        };
+        const extraHeaders = this.generateAuthHeaders(path, postData, this.options.apiSecret)
+        return this.request('post', `/${path}`, postData, extraHeaders).then(result => {
+            assert.ok(result && result.length === 5, `Unexpected response from LN Backend [POST ${path}]: data length should be 5 but is ${result.length}`);
+            const [invoiceHash, invoice, placeholder1, placeholder2, amount] = result;
+            return {
+                id: invoiceHash,
+                invoice: invoice,
+            };
+        });
+    }
+
+    getInvoiceStatus(id) {
+        return Promise.reject(new Error('Not supported by this LN service.'));
+    }
+
+    getBalance() {
+        return Promise.reject(new Error('Not supported by this LN service.'));
+    }
+
+    getNodeUri() {
+        return Promise.reject(new Error('Not supported by this LN service.'));
+    }
+
+    openChannel(remoteId, localAmt, pushAmt, makePrivate) {
+        return Promise.reject(new Error('Not supported by this LN service.'));
+    }
+
+    validateResponseBody(body) {
+        assert.ok(body.success !== false, body.message);
+    }
+};
+
+Backend.prototype.generateAuthHeaders = function (path, body, apiSecret) {
+    const nonce = (Date.now() * 1000).toString();
+    let payload = `/api/${path}${nonce}${JSON.stringify(body)}`;
+    const signature = crypto.createHmac('sha384', apiSecret).update(payload).digest('hex');
+    return {
+        'bfx-nonce': nonce,
+        'bfx-signature': signature,
+        // bfx-apikey is already set in the constructor.
+    };
+}
+
+Backend.prototype.checkMethodErrorMessages = {
+    payInvoice: {
+        ok: [
+            'Invalid payment request',
+        ],
+        notOk: [
+            'Socks5 proxy rejected connection - Failure',
+            'Invalid API key for request',
+        ],
+    },
+};
+
+Backend.form = {
+    label: '',
+    inputs: [
+        {
+            name: 'hostname',
+            label: 'Hostname',
+            type: 'text',
+            default: 'api.bitfinex.com',
+            required: true,
+        },
+        {
+            name: 'apiKey',
+            label: 'API Key',
+            type: 'text',
+            placeholder: 'xxx',
+            default: '',
+            required: true,
+        },
+        {
+            name: 'apiSecret',
+            label: 'API Secret',
+            type: 'text',
+            placeholder: 'xxx',
+            default: '',
+            required: true,
+        },
+    ],
+};
+
+module.exports = Backend;