feat: added utils.js from js-libp2p-floodsub

Author: Mikerah

src/utils.js

@@ -0,0 +1,95 @@
+'use strict'
+
+const crypto = require('libp2p-crypto')
+const bs58 = require('bs58')
+
+exports = module.exports
+
+/**
+ * Generatea random sequence number.
+ *
+ * @returns {Buffer}
+ * @private
+ */
+exports.randomSeqno = () => {
+  return crypto.randomBytes(20)
+}
+
+/**
+ * Generate a message id, based on the `from` and `seqno`.
+ *
+ * @param {string} from
+ * @param {Buffer} seqno
+ * @returns {string}
+ * @private
+ */
+exports.msgId = (from, seqno) => {
+  return from + seqno.toString('hex')
+}
+
+/**
+ * Check if any member of the first set is also a member
+ * of the second set.
+ *
+ * @param {Set|Array} a
+ * @param {Set|Array} b
+ * @returns {boolean}
+ * @private
+ */
+exports.anyMatch = (a, b) => {
+  let bHas
+  if (Array.isArray(b)) {
+    bHas = (val) => b.indexOf(val) > -1
+  } else {
+    bHas = (val) => b.has(val)
+  }
+
+  for (let val of a) {
+    if (bHas(val)) {
+      return true
+    }
+  }
+
+  return false
+}
+
+/**
+ * Make everything an array.
+ *
+ * @param {any} maybeArray
+ * @returns {Array}
+ * @private
+ */
+exports.ensureArray = (maybeArray) => {
+  if (!Array.isArray(maybeArray)) {
+    return [maybeArray]
+  }
+
+  return maybeArray
+}
+
+exports.normalizeInRpcMessages = (messages) => {
+  if (!messages) {
+    return messages
+  }
+  return messages.map((msg) => {
+    const m = Object.assign({}, msg)
+    if (Buffer.isBuffer(msg.from)) {
+      m.from = bs58.encode(msg.from)
+    }
+    return m
+  })
+}
+
+exports.normalizeOutRpcMessages = (messages) => {
+  if (!messages) {
+    return messages
+  }
+  return messages.map((msg) => {
+    const m = Object.assign({}, msg)
+    if (typeof msg.from === 'string' || msg.from instanceof String) {
+      m.from = bs58.decode(msg.from)
+    }
+    return m
+  })
+}