better Hash & Multipart, ref #34

TheNorthMemory · Aug 24, 2021 · b8ddf28 · b8ddf28
1 parent c1deda1
commit b8ddf28
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Showing 2 changed files with 63 additions and 36 deletions.
diff --git a/lib/hash.js b/lib/hash.js
@@ -1,6 +1,19 @@
 const { createHash, createHmac, timingSafeEqual } = require('crypto');
 
-const Formatter = require('./formatter');
+const { queryStringLike, ksort } = require('./formatter');
+
+/** @constant 'md5' */
+const md5 = 'md5';
+/** @constant 'hex' */
+const hex = 'hex';
+/** @constant 'sha256' */
+const sha256 = 'sha256';
+/** @constant 'sha1' */
+const sha1 = 'sha1';
+/** @constant 'MD5' */
+const ALGO_MD5 = 'MD5';
+/** @constant 'HMAC-SHA256' */
+const ALGO_HMAC_SHA256 = 'HMAC-SHA256';
 
 /**
  * Crypto hash functions utils.
@@ -20,7 +33,11 @@ class Hash {
    * @return {string} - data signature
    */
   static md5(thing, key = '', agency = false) {
-    return createHash('md5').update(thing).update(`${key ? `&${agency ? 'secret' : 'key'}=${key}` : ''}`).digest('hex');
+    return createHash(md5)
+      .update(thing)
+      .update(key ? `&${agency} ? 'secret=' : '&key='` : '')
+      .update(key)
+      .digest(hex);
   }
 
   /**
@@ -30,20 +47,24 @@ class Hash {
    * @param {string} [algorithm = sha256] - The algorithm string, default is `sha256`.
    * @return {string} - data signature
    */
-  static hmac(thing, key, algorithm = 'sha256') {
-    return createHmac(algorithm, key).update(thing).update(`&key=${key}`).digest('hex');
+  static hmac(thing, key, algorithm = sha256) {
+    return createHmac(algorithm, key)
+      .update(thing)
+      .update('&key=')
+      .update(key)
+      .digest(hex);
   }
 
   /**
-   * @deprecated {@since v0.5.5}, instead of by `hmac`
+   * @deprecated v0.5.5, use the `Hash.hmac` method instead
    *
    * Calculate the input string with a secret `key` in HMAC-SHA256
    * @param {string|Buffer} thing - The input string.
    * @param {string} key - The secret key string.
    * @return {string} - data signature
    */
   static hmacSha256(thing, key) {
-    return this.hmac(thing, key, 'sha256');
+    return this.hmac(thing, key, sha256);
   }
 
   /**
@@ -52,7 +73,7 @@ class Hash {
    * @return {string} - data signature
    */
   static sha1(thing) {
-    return createHash('sha1').update(thing).digest('hex');
+    return createHash(sha1).update(thing).digest(hex);
   }
 
   /**
@@ -61,7 +82,7 @@ class Hash {
    * @return {string} - data signature
    */
   static sha256(thing) {
-    return createHash('sha256').update(thing).digest('hex');
+    return createHash(sha256).update(thing).digest(hex);
   }
 
   /**
@@ -73,7 +94,7 @@ class Hash {
   static equals(known, user) {
     const a = Buffer.from(known);
     const b = (user === undefined || user === null) ? undefined : Buffer.from(user);
-    return undefined !== b && a.length === b.length && timingSafeEqual(a, b);
+    return Buffer.isBuffer(b) && a.length === b.length && timingSafeEqual(a, b);
   }
 
   /**
@@ -85,11 +106,11 @@ class Hash {
    */
   static sign(type, data, key) {
     const alias = {
-      MD5: this.md5,
-      'HMAC-SHA256': this.hmac,
+      [ALGO_MD5]: this.md5,
+      [ALGO_HMAC_SHA256]: this.hmac,
     };
 
-    return alias[type](Formatter.queryStringLike(Formatter.ksort(data)), key).toUpperCase();
+    return alias[type](queryStringLike(ksort(data)), key).toUpperCase();
   }
 }
 

diff --git a/lib/multipart.js b/lib/multipart.js
@@ -2,7 +2,9 @@ const { extname } = require('path');
 const { Readable } = require('stream');
 const { ReadStream } = require('fs');
 
-const { iterator, toStringTag } = Symbol;
+const HYPHENS = Buffer.from('--');
+const EMPTY = Buffer.from([]);
+const CRLF = Buffer.from('\r\n');
 
 /**
  * Simple and lite of `multipart/form-data` implementation, most similar to `form-data`.
@@ -57,9 +59,10 @@ class Multipart extends Readable {
        * @readonly
        * @memberof Multipart#
        * @prop {Buffer} dashDash - Double `dash` buffer
+       * @deprecated v1.0.0 - Only for compatible, use the literal `Buffer.from('--')` Buffer instead
        */
       dashDash: {
-        value: Buffer.from('--'),
+        value: HYPHENS,
         configurable: false,
         enumerable: false,
         writable: false,
@@ -82,9 +85,10 @@ class Multipart extends Readable {
        * @readonly
        * @memberof Multipart#
        * @prop {Buffer} EMPTY - An empty buffer
+       * @deprecated v1.0.0 - Only for compatible, use the literal `Buffer.from([])` Buffer instead
        */
       EMPTY: {
-        value: Buffer.from([]),
+        value: EMPTY,
         configurable: false,
         enumerable: false,
         writable: false,
@@ -93,10 +97,11 @@ class Multipart extends Readable {
       /**
        * @readonly
        * @memberof Multipart#
-       * @prop {Buffer} CRLF - Double `dash` buffer
+       * @prop {Buffer} CRLF - The `CRLF` characters buffer
+       * @deprecated v1.0.0 - Only for compatible, use the literal `Buffer.from('\r\n')` Buffer instead
        */
       CRLF: {
-        value: Buffer.from('\r\n'),
+        value: CRLF,
         configurable: false,
         enumerable: false,
         writable: false,
@@ -183,13 +188,11 @@ class Multipart extends Readable {
    * @returns {this} - The `Multipart` class instance self
    */
   append(name, value, filename = '') {
-    const {
-      data, dashDash, boundary, CRLF, indices,
-    } = this;
+    const { data, boundary, indices } = this;
 
-    data.splice(...(data.length ? [-2, 1] : [0, 0, dashDash, boundary, CRLF]));
+    data.splice(...(data.length ? [-2, 1] : [0, 0, HYPHENS, boundary, CRLF]));
     indices.push([name, data.push(...this.formed(name, value, filename)) - 1]);
-    data.push(CRLF, dashDash, boundary, dashDash, CRLF);
+    data.push(CRLF, HYPHENS, boundary, HYPHENS, CRLF);
 
     return this;
   }
@@ -204,7 +207,7 @@ class Multipart extends Readable {
    * @returns {Array<Buffer|ReadStream>} - The part of data
    */
   formed(name, value, filename = '') {
-    const { mimeTypes, CRLF, EMPTY } = this;
+    const { mimeTypes } = this;
     const isBufferOrStream = Buffer.isBuffer(value) || (value instanceof ReadStream);
     return [
       Buffer.from(`Content-Disposition: form-data; name="${name}"${filename && isBufferOrStream ? `; filename="${filename}"` : ''}`),
@@ -307,21 +310,21 @@ class Multipart extends Readable {
    *
    * @return {Iterator<Array<EntryTuple<string|undefined, Buffer|ReadStream>>>} - An Array Iterator key/value pairs.
    */
-  entries() { return this.indices.map(([name, index]) => [name, this.data[index]])[iterator](); }
+  entries() { return this.indices.map(([name, index]) => [name, this.data[index]])[Symbol.iterator](); }
 
   /**
    * To go through all keys contained in {@link Multipart#data} instance
    *
    * @return {Iterator<string|undefined>} - An Array Iterator key pairs.
    */
-  keys() { return this.indices.map(([name]) => name)[iterator](); }
+  keys() { return this.indices.map(([name]) => name)[Symbol.iterator](); }
 
   /**
    * To go through all values contained in {@link Multipart#data} instance
    *
    * @return {Iterator<Buffer|ReadStream>} - An Array Iterator value pairs.
    */
-  values() { return this.indices.map(([, index]) => this.data[index])[iterator](); }
+  values() { return this.indices.map(([, index]) => this.data[index])[Symbol.iterator](); }
 
   /**
    * The WeChatPay APIv3' specific, the `meta` JSON
@@ -334,32 +337,34 @@ class Multipart extends Readable {
    * alias of {@link Multipart#entries}
    * @return {Iterator<Array<EntryTuple<string|undefined, Buffer|ReadStream>>>} - An Array Iterator key/value pairs.
    */
-  [iterator]() { return this.entries(); }
+  [Symbol.iterator]() { return this.entries(); }
 
   /**
    * @returns {string} - FormData string
    */
-  static get [toStringTag]() { return 'FormData'; }
+  static get [Symbol.toStringTag]() { return 'FormData'; }
 
   /**
    * @returns {string} - FormData string
    */
-  get [toStringTag]() { return this.constructor[toStringTag]; }
+  get [Symbol.toStringTag]() { return this.constructor[Symbol.toStringTag]; }
 
   /**
    * @returns {string} - FormData string
    */
-  toString() { return `[object ${this[toStringTag]}]`; }
+  toString() { return `[object ${this[Symbol.toStringTag]}]`; }
 
   /* eslint-disable-next-line class-methods-use-this, no-underscore-dangle */
   _read() {}
 
   /**
    * Pushing {@link Multipart#data} into the readable BufferList
    *
+   * @param {boolean} [end = true] - End the writer when the reader ends. Default: `true`. Available {@since v1.0.0}
+   *
    * @returns {Promise<this>} - The Multipart instance
    */
-  async flowing() {
+  async flowing(end = true) {
     /* eslint-disable-next-line no-restricted-syntax */
     for (const value of this.data) {
       if (value instanceof ReadStream) {
@@ -371,7 +376,7 @@ class Multipart extends Readable {
         this.push(value);
       }
     }
-    this.push(null);
+    if (end) { this.push(null); }
 
     return this;
   }
@@ -385,8 +390,9 @@ class Multipart extends Readable {
    * @returns {stream.Writable} - The destination, allowing for a chain of pipes
    */
   pipe(destination, options = { end: true }) {
+    const { end = true } = options;
     super.pipe(destination, options);
-    this.flowing();
+    this.flowing(end);
     return destination;
   }
 }
@@ -396,9 +402,9 @@ try {
   /* eslint-disable-next-line global-require, import/no-unresolved, import/no-extraneous-dependencies */
   FormData = require('form-data');
   /* @see [issue#396 `Object.prototype.toString.call(form)`]{@link https://github.com/form-data/form-data/issues/396} */
-  if (!Reflect.has(FormData, toStringTag)) {
-    Reflect.set(FormData.prototype, toStringTag, 'FormData');
-    Reflect.set(FormData, toStringTag, FormData.prototype[toStringTag]);
+  if (!Reflect.has(FormData, Symbol.toStringTag)) {
+    Reflect.set(FormData.prototype, Symbol.toStringTag, 'FormData');
+    Reflect.set(FormData, Symbol.toStringTag, FormData.prototype[Symbol.toStringTag]);
   }
 } catch (e) {
   /* eslint max-classes-per-file: ["error", 2] */