Improve project name generator

ref DEV-1612

portal/src/graphql/portal/CreateProjectScreen.tsx

@@ -15,8 +15,7 @@ import { ErrorParseRule, makeReasonErrorParseRule } from "../../error/parse";
 import { useSimpleForm } from "../../hook/useSimpleForm";
 import {
   randomProjectName,
-  getRandom32BitsNumber,
-  maskNumber,
+  projectNameWithCompanyName,
 } from "../../util/projectname";
 import PrimaryButton from "../../PrimaryButton";
 
@@ -75,14 +74,6 @@ function processCompanyName(companyName: string): string {
     .toLowerCase();
 }
 
-function addRandomNumberSuffix(intermediateProjectName: string): string {
-  return (
-    intermediateProjectName +
-    "-" +
-    maskNumber(getRandom32BitsNumber(), 0, 10).toString()
-  );
-}
-
 function CreateProjectScreenContent(props: CreateProjectScreenContentProps) {
   const { numberOfApps } = props;
   const navigate = useNavigate();
@@ -104,7 +95,7 @@ function CreateProjectScreenContent(props: CreateProjectScreenContentProps) {
     if (typedState) {
       const intermediateName = processCompanyName(typedState.company_name);
       if (intermediateName !== "")
-        defaultState.appID = addRandomNumberSuffix(intermediateName);
+        defaultState.appID = projectNameWithCompanyName(intermediateName);
     }
     return defaultState;
   }, [state]);

portal/src/util/projectname.test.ts

@@ -1,47 +1,69 @@
 import { describe, it, expect } from "@jest/globals";
-import { maskNumber, deterministicProjectName } from "./projectname";
+import {
+  deterministicProjectName,
+  extractBits,
+  projectNameWithCompanyName,
+} from "./projectname";
 
-describe("maskNumber", () => {
-  it("should mask the number starting from 0 bit and get 11 bits after it", () => {
-    expect(maskNumber(12345678, 0, 11)).toEqual(334);
+describe("extractBits", () => {
+  it("should handle bytes that look like signed bits", () => {
+    expect(
+      extractBits(
+        new Uint8Array([
+          0b10000000, 0b10000001, 0b10000010, 0b10000011, 0b10000100,
+          0b10000101,
+        ])
+      )
+    ).toEqual([0b10000000100, 0b0000110000010100000111000010010]);
   });
 
-  it("should mask the number starting from 20 bit and get 5 bits after it", () => {
-    expect(maskNumber(12345678, 20, 5)).toEqual(11);
+  it("should handle bytes", () => {
+    expect(
+      extractBits(
+        new Uint8Array([
+          0b00000000, 0b00000001, 0b00000010, 0b00000011, 0b00000100,
+          0b00000101,
+        ])
+      )
+    ).toEqual([0b00000000000, 0b0000100000010000000110000010000]);
   });
 });
 
 describe("deterministicProjectName", () => {
-  it("deterministicProjectName(0) is 'abandon-abandon-0'", () => {
-    // 0 is 0b00000000000_00000000000_0000000000
-    // 0b00000000000 is abandon
-    // 0b0000000000 is 0
-    // So the name is abandon-abandon-0
-    expect(deterministicProjectName(0)).toEqual("abandon-abandon-0");
+  it("deterministicProjectName([0, 0, 0, 0, 0, 0]) is 'abandon-000000'", () => {
+    // [0, 0, 0, 0, 0, 0] is 0b00000000000_0000000000000000000000000000000_000000
+    // 0b00000000000 is 'abandon'
+    // 0000000000000000000000000000000 is '000000'
+    // last 6 bits 000000 is not used
+    // So the name is 'abandon-000000'
+    const fortyEightBits = new Uint8Array([0, 0, 0, 0, 0, 0]);
+    expect(deterministicProjectName(fortyEightBits)).toEqual("abandon-000000");
   });
 
-  it("deterministicProjectName(1) is ''", () => {
-    // 1 is 0b00000000000_00000000000_0000000001
-    // 0b00000000000 is abandon
-    // 0b0000000001 is 1
-    // So the name is abandon-abandon-1
-    expect(deterministicProjectName(1)).toEqual("abandon-abandon-1");
+  it("deterministicProjectName([0, 0, 0, 0, 1, 0]) is 'abandon-000004'", () => {
+    // [0, 0, 0, 0, 1, 0] is 0b00000000000_0000000000000000000000000000100_000000
+    // 0b00000000000 is 'abandon'
+    // 0000000000000000000000000000100 is '000004'
+    // last 6 bits 000000 is not used
+    // So the name is 'abandon-000000'
+    const fortyEightBits = new Uint8Array([0, 0, 0, 0, 1, 0]);
+    expect(deterministicProjectName(fortyEightBits)).toEqual("abandon-000004");
   });
 
-  it("deterministicProjectName(87878787) is ''", () => {
-    // 87878787 is 0b00000101001_11100111011_0010000011
-    // 0b00000101001 is ahead
-    // 0b11100111011 is trash
-    // 0b0010000011 is 131
-    // So the name is ahead-trash-131
-    expect(deterministicProjectName(87878787)).toEqual("ahead-trash-131");
+  it("deterministicProjectName([87, 87, 87, 87, 87, 87]) is 'firm-pwldul' ", () => {
+    // [87, 87, 87, 87, 87, 87] is 0b01010111010_1011101010111010101110101011101_010111
+    // 0b0b01010111010 is 'firm'
+    // 1011101010111010101110101011101 is 'pwldul'
+    // last 6 bits 010111 is not used
+    // So the name is 'firm-000000'
+    const fortyEightBits = new Uint8Array([87, 87, 87, 87, 87, 87]);
+    expect(deterministicProjectName(fortyEightBits)).toEqual("firm-pwldul");
   });
+});
 
-  it("deterministicProjectName(4294967295) is ''", () => {
-    // 4294967295 (2^32 - 1) is 0b11111111111_11111111111_1111111111
-    // 0b11111111111 is zoo
-    // 0b1111111111 is 1023
-    // So the name is zoo-zoo-1023
-    expect(deterministicProjectName(4294967295)).toEqual("zoo-zoo-1023");
+describe("projectNameWithCompanyName", () => {
+  it("projectNameWithCompanyName('authgear') starts with 'authgear-` and ends with 6 lowercase-alphanumeric characters", () => {
+    const authgearProjectName = projectNameWithCompanyName("authgear");
+    expect(authgearProjectName).toMatch(/^authgear-[a-z0-9]{6}$/);
   });
 });

portal/src/util/projectname.ts

@@ -5,27 +5,86 @@ function determineWord(index: number): string {
   return wordlist[index];
 }
 
-export function getRandom32BitsNumber(): number {
-  const randomBuffer = new Uint32Array(1);
+export function getRandom48Bits(): Uint8Array {
+  const randomBuffer = new Uint8Array(6);
   window.crypto.getRandomValues(randomBuffer);
-  return randomBuffer[0];
+  return randomBuffer;
 }
 
-export function maskNumber(num: number, startAt: number, bits: number): number {
-  return (num >> startAt) & ((1 << bits) - 1);
+/**
+ * This function take 48 bits, and split into 2 numbers, bit_0_10 and bit_11_41, dropping the last 6 bits
+ *
+ * @export
+ * @param {Uint8Array} fortyEightBits
+ * @returns {[number, number]}
+ */
+export function extractBits(fortyEightBits: Uint8Array): [number, number] {
+  const bit_0_7 = fortyEightBits[0];
+  const bit_8_15 = fortyEightBits[1];
+  const bit_16_23 = fortyEightBits[2];
+  const bit_24_31 = fortyEightBits[3];
+  const bit_32_39 = fortyEightBits[4];
+  const bit_40_47 = fortyEightBits[5];
+
+  // 11 bits are needed, there are 2^11 = 2048 words in the wordlist
+  const bit_0_10 = (bit_0_7 << 3) | (bit_8_15 >>> 5);
+
+  const bit_11_15 = bit_8_15 & 0b00011111;
+  const bit_40_41 = bit_40_47 >>> 6;
+
+  // 31 bits are needed. We need 6 lowercase-alphanumeric characters.
+  // There are 36 lowercase-alphanumeric characters in total.
+  // log36(2^31) = 5.996...
+  const bit_11_41 =
+    (bit_11_15 << 26) |
+    (bit_16_23 << 18) |
+    (bit_24_31 << 10) |
+    (bit_32_39 << 2) |
+    bit_40_41;
+
+  return [bit_0_10, bit_11_41];
+}
+
+export function deterministicAlphanumericString(bits: number): string {
+  const string = bits.toString(36);
+
+  if (string.length > 6) {
+    throw new Error("number of bits must be less than 31");
+  }
+
+  const zeroPaddedString = string.padStart(6, "0");
+  return zeroPaddedString;
 }
 
-export function deterministicProjectName(num: number): string {
-  const randomNumber = maskNumber(num, 0, 10);
-  const secondRandomStringIndex = maskNumber(num, 10, 11);
-  const firstRandomStringIndex = maskNumber(num, 21, 11);
+/**
+ * This function take 48 bits
+ * The  1st - 11th bits bit_0_10 are used to determine the word
+ * The 12th - 42nd bits bit_11_41 are used to determine the alphanumeric string
+ * The 43rd - 48th bits bit_42_47 are not used
+ *
+ * @export
+ * @param {Uint8Array} fortyEightBits Uint8Array of length 6
+ * @returns {string}
+ */
+export function deterministicProjectName(fortyEightBits: Uint8Array): string {
+  if (fortyEightBits.length !== 6) {
+    throw new Error("fortyEightBits must be 6 bytes");
+  }
+  const [bit_0_10, bit_11_41] = extractBits(fortyEightBits);
+  const firstRandomString = determineWord(bit_0_10);
 
-  const firstRandomString = determineWord(firstRandomStringIndex);
-  const secondRandomString = determineWord(secondRandomStringIndex);
+  const alphaNumericString = deterministicAlphanumericString(bit_11_41);
 
-  return `${firstRandomString}-${secondRandomString}-${randomNumber}`;
+  return `${firstRandomString}-${alphaNumericString}`;
 }
 
 export function randomProjectName(): string {
-  return deterministicProjectName(getRandom32BitsNumber());
+  return deterministicProjectName(getRandom48Bits());
+}
+
+export function projectNameWithCompanyName(companyName: string): string {
+  const randomBits = getRandom48Bits();
+  const [_, thirtyOneBits] = extractBits(randomBits);
+  const alphaNumericString = deterministicAlphanumericString(thirtyOneBits);
+  return `${companyName}-${alphaNumericString}`;
 }