feat: v4, compare with old hashing implementation. Do not merge!

.github/workflows/pull_request.yaml

@@ -14,20 +14,14 @@ jobs:
   build-and-test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - name: Checkout submodules # checkout rest
-        shell: bash
-        run: |
-          # If your submodules are configured to use SSH instead of HTTPS please uncomment the following line
-          git config --global url."https://github.com/".insteadOf "[email protected]:"
-          auth_header="$(git config --local --get http.https://github.com/.extraheader)"
-          git submodule sync --recursive
-          git -c "http.extraheader=$auth_header" -c protocol.version=2 submodule update --init --force --recursive --depth=1
+      - uses: actions/checkout@v4
+        with:
+          submodules: true
       - uses: actions/setup-node@v4
         with:
           node-version: "18.x"
       - name: cache node modules
-        uses: actions/cache@v1
+        uses: actions/cache@v4
         with:
           path: ~/.npm # npm cache files are stored in `~/.npm` on Linux/macOS
           key: npm-${{ hashFiles('package-lock.json') }}

flagsmith-engine/features/models.ts

@@ -1,4 +1,4 @@
-import { v4 as uuidv4 } from 'uuid';
+import { randomUUID as uuidv4 } from "node:crypto";
 import { getHashedPercentateForObjIds } from '../utils/hashing/index.js';
 
 export class FeatureModel {

flagsmith-engine/identities/models.ts

@@ -1,7 +1,7 @@
 import { IdentityFeaturesList } from '../utils/collections.js';
 import { TraitModel } from './traits/models.js';
 
-const { v4: uuidv4 } = require('uuid');
+import { randomUUID as uuidv4 } from 'node:crypto';
 
 export class IdentityModel {
     identifier: string;

flagsmith-engine/segments/models.ts

@@ -1,4 +1,4 @@
-import semver from 'semver';
+import * as semver from 'semver';
 
 import { FeatureStateModel } from '../features/models.js';
 import { getCastingFunction as getCastingFunction } from '../utils/index.js';

flagsmith-engine/utils/hashing/index.ts

@@ -1,10 +1,10 @@
-import md5 from 'md5';
-import bigInt from 'big-integer';
+import {BinaryLike, createHash} from "node:crypto";
+
+const md5 = (data: BinaryLike) => createHash('md5').update(data).digest('hex')
 
 const makeRepeated = (arr: Array<any>, repeats: number) =>
     Array.from({ length: repeats }, () => arr).flat();
 
-// https://stackoverflow.com/questions/12532871/how-to-convert-a-very-large-hex-number-to-decimal-in-javascript
 function h2d(s: any): string {
     function add(x: any, y: any) {
         var c = 0,
@@ -30,6 +30,27 @@ function h2d(s: any): string {
     });
     return dec;
 }
+
+
+import bigInt from 'big-integer'
+export function getHashedPercentateForObjIdsOld(objectIds: Array<any>, iterations = 1): number {
+    let toHash = makeRepeated(objectIds, iterations).join(',');
+    const hashedValue = md5(toHash);
+    const hashedInt = bigInt(h2d(hashedValue));
+    const value = (hashedInt.mod(9999).toJSNumber() / 9998) * 100;
+
+    // we ignore this for it's nearly impossible use case to catch
+    /* istanbul ignore next */
+    if (value === 100) {
+        /* istanbul ignore next */
+        return getHashedPercentateForObjIdsOld(objectIds, iterations + 1);
+    }
+
+    return value;
+}
+
+
+// https://stackoverflow.com/questions/12532871/how-to-convert-a-very-large-hex-number-to-decimal-in-javascript
 /**
  * Given a list of object ids, get a floating point number between 0 and 1 based on
  * the hash of those ids. This should give the same value every time for any list of ids.
@@ -41,8 +62,8 @@ function h2d(s: any): string {
 export function getHashedPercentateForObjIds(objectIds: Array<any>, iterations = 1): number {
     let toHash = makeRepeated(objectIds, iterations).join(',');
     const hashedValue = md5(toHash);
-    const hashedInt = bigInt(h2d(hashedValue));
-    const value = (hashedInt.mod(9999).toJSNumber() / 9998) * 100;
+    const hashedInt = BigInt('0x' + hashedValue);
+    const value = (Number((hashedInt % 9999n)) / 9998.0) * 100;
 
     // we ignore this for it's nearly impossible use case to catch
     /* istanbul ignore next */

index.ts

@@ -1,5 +1,3 @@
-import Flagsmith from "./sdk/index.js";
-
 export {
   AnalyticsProcessor,
   FlagsmithAPIError,
@@ -8,7 +6,7 @@ export {
   FlagsmithCache,
   DefaultFlag,
   Flags,
-  default
+  Flagsmith,
 } from './sdk/index.js';
 
 export {
@@ -23,5 +21,3 @@ export {
   SegmentModel,
   OrganisationModel
 } from './flagsmith-engine/index.js';
-
-module.exports = Flagsmith;