fix(better-auth): support custom table enum field types and defaults

packages/auth-adapters/better-auth/package.json

@@ -7,6 +7,7 @@
         "build": "tsc --noEmit && tsup-node",
         "watch": "tsup-node --watch",
         "lint": "eslint src --ext ts",
+        "test": "vitest run",
         "pack": "pnpm pack"
     },
     "keywords": [
@@ -47,8 +48,12 @@
     "devDependencies": {
         "@better-auth/core": "^1.3.0",
         "better-auth": "^1.3.0",
+        "@better-auth/cli": "^1.3.0",
+        "@types/tmp": "catalog:",
+        "@zenstackhq/cli": "workspace:*",
         "@zenstackhq/eslint-config": "workspace:*",
         "@zenstackhq/typescript-config": "workspace:*",
-        "@zenstackhq/vitest-config": "workspace:*"
+        "@zenstackhq/vitest-config": "workspace:*",
+        "tmp": "catalog:"
     }
 }

packages/auth-adapters/better-auth/src/schema-generator.ts

@@ -16,6 +16,7 @@ import {
     InvocationExpr,
     isDataModel,
     Model,
+    NumberLiteral,
     ReferenceExpr,
     StringLiteral,
 } from '@zenstackhq/language/ast';
@@ -260,6 +261,11 @@ function getMappedFieldType({ bigint, type }: DBFieldAttribute) {
         .with('string[]', () => ({ type: 'String', array: true }))
         .with('number[]', () => ({ type: 'Int', array: true }))
         .otherwise(() => {
+            // Handle enum types (e.g., ['user', 'admin'] or "user,admin")
+            // Map them to String type for now
+            if (Array.isArray(type) || (typeof type === 'string' && type.includes(','))) {
+                return { type: 'String' };
+            }
             throw new Error(`Unsupported field type: ${type}`);
         });
 }
@@ -332,6 +338,10 @@ function addOrUpdateModel(
                     addDefaultNow(df);
                 } else if (typeof field.defaultValue === 'boolean') {
                     addFieldAttribute(df, '@default', [createBooleanAttributeArg(field.defaultValue)]);
+                } else if (typeof field.defaultValue === 'string') {
+                    addFieldAttribute(df, '@default', [createStringAttributeArg(field.defaultValue)]);
+                } else if (typeof field.defaultValue === 'number') {
+                    addFieldAttribute(df, '@default', [createNumberAttributeArg(field.defaultValue)]);
                 } else if (typeof field.defaultValue === 'function') {
                     // For other function-based defaults, we'll need to check what they return
                     const defaultVal = field.defaultValue();
@@ -537,6 +547,19 @@ function createBooleanAttributeArg(value: boolean) {
     return arg;
 }
 
+function createNumberAttributeArg(value: number) {
+    const arg: AttributeArg = {
+        $type: 'AttributeArg',
+    } as any;
+    const expr: NumberLiteral = {
+        $type: 'NumberLiteral',
+        value: value.toString(),
+        $container: arg,
+    };
+    arg.value = expr;
+    return arg;
+}
+
 function createStringAttributeArg(value: string) {
     const arg: AttributeArg = {
         $type: 'AttributeArg',

packages/auth-adapters/better-auth/test/auth-custom.ts

@@ -0,0 +1,33 @@
+import { zenstackAdapter } from '../src/adapter';
+import { betterAuth } from 'better-auth';
+
+export const auth = betterAuth({
+    database: zenstackAdapter({} as any, {
+        provider: 'postgresql',
+    }),
+    user: {
+        additionalFields: {
+            role: {
+                type: ['user', 'admin'],
+                required: false,
+                defaultValue: 'user',
+                input: false, // don't allow user to set role
+            },
+            lang: {
+                type: 'string',
+                required: false,
+                defaultValue: 'en',
+            },
+            age: {
+                type: 'number',
+                required: true,
+                defaultValue: 18,
+            },
+            admin: {
+                type: 'boolean',
+                required: false,
+                defaultValue: false,
+            },
+        },
+    },
+});

packages/auth-adapters/better-auth/test/auth.ts

@@ -0,0 +1,8 @@
+import { zenstackAdapter } from '../src/adapter';
+import { betterAuth } from 'better-auth';
+
+export const auth = betterAuth({
+    database: zenstackAdapter({} as any, {
+        provider: 'postgresql',
+    }),
+});

packages/auth-adapters/better-auth/test/cli-generate.test.ts

@@ -0,0 +1,65 @@
+import { execSync } from 'node:child_process';
+import fs from 'node:fs';
+import path from 'node:path';
+import { describe, expect, it } from 'vitest';
+import { fileURLToPath } from 'node:url';
+import tmp from 'tmp';
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+
+/**
+ * Helper function to generate schema using better-auth CLI
+ */
+function generateSchema(configFile: string): string {
+    const { name: workDir } = tmp.dirSync({ unsafeCleanup: true });
+    const schemaPath = path.join(workDir, 'schema.zmodel');
+    const configPath = path.join(__dirname, configFile);
+
+    execSync(`pnpm better-auth generate --config ${configPath} --output ${schemaPath} --yes`, {
+        cwd: __dirname,
+        stdio: 'pipe',
+    });
+
+    return schemaPath;
+}
+
+/**
+ * Helper function to verify schema with zenstack check
+ */
+function verifySchema(schemaPath: string) {
+    const cliPath = path.join(__dirname, '../../../cli/dist/index.js');
+    const workDir = path.dirname(schemaPath);
+
+    expect(fs.existsSync(schemaPath)).toBe(true);
+
+    expect(() => {
+        execSync(`node ${cliPath} check --schema ${schemaPath}`, {
+            cwd: workDir,
+            stdio: 'pipe',
+        });
+    }).not.toThrow();
+}
+
+describe('Cli schema generation tests', () => {
+    it('works with simple config', async () => {
+        const schemaPath = generateSchema('auth.ts');
+        verifySchema(schemaPath);
+    });
+
+    it('works with custom config', async () => {
+        const schemaPath = generateSchema('auth-custom.ts');
+        verifySchema(schemaPath);
+
+        // Verify that the generated schema contains the expected default values
+        const schemaContent = fs.readFileSync(schemaPath, 'utf-8');
+        expect(schemaContent).toMatch(/role\s+String/);
+        expect(schemaContent).toContain("@default('user')");
+        expect(schemaContent).toMatch(/lang\s+String/);
+        expect(schemaContent).toContain("@default('en')");
+        expect(schemaContent).toMatch(/age\s+Int/);
+        expect(schemaContent).toContain('@default(18)');
+        expect(schemaContent).toMatch(/admin\s+Boolean/);
+        expect(schemaContent).toContain('@default(false)');
+    });
+});