Fixed fast-base64-decode dependency issue in react-native-package. (#286)

Author: Chriztiaan

.changeset/pretty-teachers-press.md

@@ -0,0 +1,5 @@
+---
+'@powersync/react-native': patch
+---
+
+Updated crypto.js vendor file to include fast-base64-decode dependency instead of bundling it.

packages/react-native/package.json

@@ -50,7 +50,6 @@
     "@types/async-lock": "^1.4.0",
     "async-lock": "^1.4.0",
     "bson": "^6.6.0",
-    "fast-base64-decode": "^1.0.0",
     "react": "18.2.0",
     "react-native": "0.72.4",
     "react-native-fetch-api": "^3.0.0",

packages/react-native/vendor/crypto.js

@@ -1,85 +1,152 @@
-// This file is based on code from the react-native-get-random-values repository
+// This file is based on code from the fast-base64-decode repository.
+// Source: https://github.com/LinusU/fast-base64-decode/blob/master/index.js
+// Modifications:
+// - None
+
+const lookup = new Uint8Array([
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 62, 0, 62, 0, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8,
+  9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 0, 0, 0, 0, 63, 0, 26, 27, 28, 29, 30, 31, 32, 33,
+  34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51
+]);
+
+function base64Decode(source, target) {
+  const sourceLength = source.length;
+  const paddingLength = source[sourceLength - 2] === '=' ? 2 : source[sourceLength - 1] === '=' ? 1 : 0;
+  const baseLength = (sourceLength - paddingLength) & 0xfffffffc;
+
+  let tmp;
+  let i = 0;
+  let byteIndex = 0;
+
+  for (; i < baseLength; i += 4) {
+    tmp =
+      (lookup[source.charCodeAt(i)] << 18) |
+      (lookup[source.charCodeAt(i + 1)] << 12) |
+      (lookup[source.charCodeAt(i + 2)] << 6) |
+      lookup[source.charCodeAt(i + 3)];
+
+    target[byteIndex++] = (tmp >> 16) & 0xff;
+    target[byteIndex++] = (tmp >> 8) & 0xff;
+    target[byteIndex++] = tmp & 0xff;
+  }
+
+  if (paddingLength === 1) {
+    tmp =
+      (lookup[source.charCodeAt(i)] << 10) |
+      (lookup[source.charCodeAt(i + 1)] << 4) |
+      (lookup[source.charCodeAt(i + 2)] >> 2);
+
+    target[byteIndex++] = (tmp >> 8) & 0xff;
+    target[byteIndex++] = tmp & 0xff;
+  }
+
+  if (paddingLength === 2) {
+    tmp = (lookup[source.charCodeAt(i)] << 2) | (lookup[source.charCodeAt(i + 1)] >> 4);
+
+    target[byteIndex++] = tmp & 0xff;
+  }
+}
+
+// This file is based on code from the react-native-get-random-values repository.
 // Source: https://github.com/LinusU/react-native-get-random-values/blob/modern/index.js
 // Modifications:
 // - Instead of applying to all global references of crypto, provide a ponyfill export.
+// - Instead of having a package dependency on fast-base64-decode, copy the code here. There are issues with injecting a vendor file in the rollup config.
 
-const base64Decode = require('fast-base64-decode')
-const { NativeModules } = require('react-native')
+const { NativeModules } = require('react-native');
 
 class TypeMismatchError extends Error {}
 class QuotaExceededError extends Error {}
 
-let warned = false
-function insecureRandomValues (array) {
+let warned = false;
+function insecureRandomValues(array) {
   if (!warned) {
-    console.warn('Using an insecure random number generator, this should only happen when running in a debugger without support for crypto.getRandomValues')
-    warned = true
+    console.warn(
+      'Using an insecure random number generator, this should only happen when running in a debugger without support for crypto.getRandomValues'
+    );
+    warned = true;
   }
 
   for (let i = 0, r; i < array.length; i++) {
-    if ((i & 0x03) === 0) r = Math.random() * 0x100000000
-    array[i] = (r >>> ((i & 0x03) << 3)) & 0xff
+    if ((i & 0x03) === 0) r = Math.random() * 0x100000000;
+    array[i] = (r >>> ((i & 0x03) << 3)) & 0xff;
   }
 
-  return array
+  return array;
 }
 
 /**
  * @param {number} byteLength
  * @returns {string}
  */
-function getRandomBase64 (byteLength) {
+function getRandomBase64(byteLength) {
   if (NativeModules.RNGetRandomValues) {
-    return NativeModules.RNGetRandomValues.getRandomBase64(byteLength)
+    return NativeModules.RNGetRandomValues.getRandomBase64(byteLength);
   } else if (NativeModules.ExpoRandom) {
     // Expo SDK 41-44
-    return NativeModules.ExpoRandom.getRandomBase64String(byteLength)
+    return NativeModules.ExpoRandom.getRandomBase64String(byteLength);
   } else if (global.ExpoModules) {
     // Expo SDK 45+
     return global.ExpoModules.ExpoRandom.getRandomBase64String(byteLength);
   } else {
-    throw new Error('Native module not found')
+    throw new Error('Native module not found');
   }
 }
 
 /**
  * @param {Int8Array|Uint8Array|Int16Array|Uint16Array|Int32Array|Uint32Array|Uint8ClampedArray} array
  */
-function getRandomValues (array) {
-  if (!(array instanceof Int8Array || array instanceof Uint8Array || array instanceof Int16Array || array instanceof Uint16Array || array instanceof Int32Array || array instanceof Uint32Array || array instanceof Uint8ClampedArray)) {
-    throw new TypeMismatchError('Expected an integer array')
+function getRandomValues(array) {
+  if (
+    !(
+      array instanceof Int8Array ||
+      array instanceof Uint8Array ||
+      array instanceof Int16Array ||
+      array instanceof Uint16Array ||
+      array instanceof Int32Array ||
+      array instanceof Uint32Array ||
+      array instanceof Uint8ClampedArray
+    )
+  ) {
+    throw new TypeMismatchError('Expected an integer array');
   }
 
   if (array.byteLength > 65536) {
-    throw new QuotaExceededError('Can only request a maximum of 65536 bytes')
+    throw new QuotaExceededError('Can only request a maximum of 65536 bytes');
   }
 
   // Expo SDK 48+
-  if (global.expo && global.expo.modules && global.expo.modules.ExpoCrypto && global.expo.modules.ExpoCrypto.getRandomValues) {
+  if (
+    global.expo &&
+    global.expo.modules &&
+    global.expo.modules.ExpoCrypto &&
+    global.expo.modules.ExpoCrypto.getRandomValues
+  ) {
     // ExpoCrypto.getRandomValues doesn't return the array
-    global.expo.modules.ExpoCrypto.getRandomValues(array)
-    return array
+    global.expo.modules.ExpoCrypto.getRandomValues(array);
+    return array;
   }
 
   // Calling getRandomBase64 in remote debugging mode leads to the error
   // "Calling synchronous methods on native modules is not supported in Chrome".
   // So in that specific case we fall back to just using Math.random().
   if (isRemoteDebuggingInChrome()) {
-    return insecureRandomValues(array)
+    return insecureRandomValues(array);
   }
 
-  base64Decode(getRandomBase64(array.byteLength), new Uint8Array(array.buffer, array.byteOffset, array.byteLength))
+  base64Decode(getRandomBase64(array.byteLength), new Uint8Array(array.buffer, array.byteOffset, array.byteLength));
 
-  return array
+  return array;
 }
 
-function isRemoteDebuggingInChrome () {
+function isRemoteDebuggingInChrome() {
   // Remote debugging in Chrome is not supported in bridgeless
   if ('RN$Bridgeless' in global && RN$Bridgeless === true) {
-    return false
+    return false;
   }
 
-  return __DEV__ && typeof global.nativeCallSyncHook === 'undefined'
+  return __DEV__ && typeof global.nativeCallSyncHook === 'undefined';
 }
 
 export default { getRandomValues };