fix: expose sha (#66)

Author: hugomrdias

package.json

@@ -42,7 +42,7 @@
     "murmurhash3js-revisited": "^3.0.0"
   },
   "devDependencies": {
-    "aegir": "^20.1.0",
+    "aegir": "^21.3.0",
     "benchmark": "^2.1.4",
     "chai": "^4.1.2",
     "dirty-chai": "^2.0.1",

src/crypto.js

@@ -3,7 +3,7 @@
 const { Buffer } = require('buffer')
 const sha3 = require('js-sha3')
 const mur = require('murmurhash3js-revisited')
-const sha = require('./sha')
+const { factory: sha } = require('./sha')
 const { fromNumberTo32BitBuf } = require('./utils')
 
 // Note that although this function doesn't do any asynchronous work, we mark

src/sha.browser.js

@@ -1,30 +1,40 @@
+/* eslint-disable require-await */
 'use strict'
 
 const { Buffer } = require('buffer')
+const multihash = require('multihashes')
 
 const crypto = self.crypto || self.msCrypto
 
-module.exports = (algorithm) => {
+const digest = async (data, alg) => {
   if (typeof self === 'undefined' || (!self.crypto && !self.msCrypto)) {
     throw new Error(
       'Please use a browser with webcrypto support and ensure the code has been delivered securely via HTTPS/TLS and run within a Secure Context'
     )
   }
-
-  return async (data) => {
-    switch (algorithm) {
-      case 'sha1':
-        return Buffer.from(await crypto.subtle.digest({ name: 'SHA-1' }, data))
-      case 'sha2-256':
-        return Buffer.from(await crypto.subtle.digest({ name: 'SHA-256' }, data))
-      case 'sha2-512':
-        return Buffer.from(await crypto.subtle.digest({ name: 'SHA-512' }, data))
-      case 'dbl-sha2-256': {
-        const d = await crypto.subtle.digest({ name: 'SHA-256' }, data)
-        return Buffer.from(await crypto.subtle.digest({ name: 'SHA-256' }, d))
-      }
-      default:
-        throw new Error(`${algorithm} is not a supported algorithm`)
+  switch (alg) {
+    case 'sha1':
+      return Buffer.from(await crypto.subtle.digest({ name: 'SHA-1' }, data))
+    case 'sha2-256':
+      return Buffer.from(await crypto.subtle.digest({ name: 'SHA-256' }, data))
+    case 'sha2-512':
+      return Buffer.from(await crypto.subtle.digest({ name: 'SHA-512' }, data))
+    case 'dbl-sha2-256': {
+      const d = await crypto.subtle.digest({ name: 'SHA-256' }, data)
+      return Buffer.from(await crypto.subtle.digest({ name: 'SHA-256' }, d))
     }
+    default:
+      throw new Error(`${alg} is not a supported algorithm`)
+  }
+}
+
+module.exports = {
+  factory: (alg) => async (data) => {
+    return digest(data, alg)
+  },
+  digest,
+  multihashing: async (buf, alg, length) => {
+    const h = await digest(buf, alg, length)
+    return multihash.encode(h, alg, length)
   }
 }

src/sha.js

@@ -1,12 +1,14 @@
+/* eslint-disable require-await */
 'use strict'
 const crypto = require('crypto')
+const multihash = require('multihashes')
 
 // Note that although this function doesn't do any asynchronous work, we mark
 // the function as async because it must return a Promise to match the API
 // for other functions that do perform asynchronous work (see sha.browser.js)
 // eslint-disable-next-line
-module.exports = (algorithm) => async (data) => {
-  switch (algorithm) {
+const digest = async (data, alg) => {
+  switch (alg) {
     case 'sha1':
       return crypto.createHash('sha1').update(data).digest()
     case 'sha2-256':
@@ -18,6 +20,17 @@ module.exports = (algorithm) => async (data) => {
       return crypto.createHash('sha256').update(first).digest()
     }
     default:
-      throw new Error(`${algorithm} is not a supported algorithm`)
+      throw new Error(`${alg} is not a supported algorithm`)
+  }
+}
+
+module.exports = {
+  factory: (alg) => async (data) => {
+    return digest(data, alg)
+  },
+  digest,
+  multihashing: async (buf, alg, length) => {
+    const h = await digest(buf, alg, length)
+    return multihash.encode(h, alg, length)
   }
 }