feat: implement new typescript code generators

Author: mjfaga

.eslintrc.json

@@ -9,7 +9,11 @@
     "no-throw-literal": "off",
     "no-warning-comments": "off",
     "unicorn/consistent-destructuring": "off",
+    "unicorn/no-array-for-each": "off",
+    "unicorn/no-array-reduce": "off",
     "unicorn/prefer-ternary": "off",
+    "unicorn/switch-case-braces": "off",
+    "padding-line-between-statements": "off",
     "prefer-destructuring": "off"
   },
   "overrides": [

package.json

@@ -11,8 +11,10 @@
     "acorn": "^8.10.0",
     "acorn-walk": "^8.2.0",
     "chalk": "^5.4.1",
+    "common-tags": "^1.8.2",
     "fuzzy": "^0.1.3",
     "inquirer-autocomplete-standalone": "^0.8.1",
+    "lodash.camelcase": "^4.3.0",
     "mustache": "^4.2.0",
     "zod": "^3.22.4"
   },
@@ -21,6 +23,8 @@
     "@oclif/prettier-config": "^0.2.1",
     "@oclif/test": "^3",
     "@types/chai": "^4",
+    "@types/common-tags": "^1.8.4",
+    "@types/lodash.camelcase": "^4.3.9",
     "@types/mocha": "^10",
     "@types/mustache": "^4.2.5",
     "@types/node": "^18",

src/codegen/code-generators/base-generator.ts

@@ -1,6 +1,6 @@
 import {type ConfigFile} from '../types.js'
 
-interface BaseGeneratorArgs {
+export interface BaseGeneratorArgs {
   configFile: ConfigFile
   log: (category: string | unknown, message?: unknown) => void
 }

src/codegen/code-generators/base-typescript-generator.ts

@@ -0,0 +1,44 @@
+import {z} from 'zod'
+
+import {ZodToTypescriptMapper} from '../language-mappers/zod-to-typescript-mapper.js'
+import {SchemaExtractor} from '../schema-extractor.js'
+import {BaseGenerator, BaseGeneratorArgs} from './base-generator.js'
+
+export abstract class BaseTypescriptGenerator extends BaseGenerator {
+  protected MUSTACHE_IMPORT = "import Mustache from 'mustache'"
+  private schemaExtractor: SchemaExtractor
+
+  constructor({configFile, log}: BaseGeneratorArgs) {
+    super({configFile, log})
+    this.schemaExtractor = new SchemaExtractor(log)
+  }
+
+  protected configurations() {
+    return this.configFile.configs
+      .filter((config) => config.configType === 'FEATURE_FLAG' || config.configType === 'CONFIG')
+      .filter((config) => config.rows.length > 0)
+      .sort((a, b) => a.key.localeCompare(b.key))
+      .map((config) => {
+        const schema = this.schemaExtractor.execute({
+          config,
+          configFile: this.configFile,
+          durationTypeMap: this.durationTypeMap,
+        })
+
+        return {
+          configType: config.configType,
+          hasFunction: schema && new ZodToTypescriptMapper().resolveType(schema).includes('=>'),
+          key: config.key,
+          schema,
+          sendToClientSdk: config.sendToClientSdk ?? false,
+        }
+      })
+  }
+
+  protected durationTypeMap(): z.ZodTypeAny {
+    return z.number()
+  }
+
+  abstract get filename(): string
+  abstract generate(): string
+}

src/codegen/code-generators/node-typescript-generator.ts

@@ -0,0 +1,105 @@
+import {stripIndent} from 'common-tags'
+import camelCase from 'lodash.camelcase'
+
+import {ZodToTypescriptMapper, type ZodToTypescriptMapperTarget} from '../language-mappers/zod-to-typescript-mapper.js'
+import {ZodToTypescriptReturnValueMapper} from '../language-mappers/zod-to-typescript-return-value-mapper.js'
+import {BaseTypescriptGenerator} from './base-typescript-generator.js'
+
+export class NodeTypeScriptGenerator extends BaseTypescriptGenerator {
+  get filename(): string {
+    return 'prefab-server.ts'
+  }
+
+  generate(): string {
+    return stripIndent`
+    /* eslint-disable */
+    // AUTOGENERATED by prefab-cli's 'gen' command
+    import {Prefab, Contexts} from '@prefab-cloud/prefab-cloud-node'
+    ${this.additionalDependencies().join('\n') || '// No additional dependencies required'}
+
+    type ContextObj = Record<string, Record<string, unknown>>
+
+    declare namespace PrefabTypeGeneration {
+      export type NodeServerConfigurationRaw = {
+        ${this.generateSchemaTypes('raw').join('\n        ') || '// No types generated'}
+      }
+
+      export type NodeServerConfigurationAccessor = {
+        ${this.generateSchemaTypes().join('\n        ') || '// No types generated'}
+      }
+    }
+
+    export class PrefabTypesafeNode {
+      constructor(private prefab: Prefab) { }
+
+      get<K extends keyof PrefabTypeGeneration.NodeServerConfigurationRaw>(key: K, contexts?: Contexts | ContextObj): PrefabTypeGeneration.NodeServerConfigurationRaw[K] {
+        return this.prefab.get(key, contexts) as PrefabTypeGeneration.NodeServerConfigurationRaw[K]
+      }
+
+      ${this.generateAccessorMethods().join('\n\n      ') || '// No methods generated'}
+    }
+    `
+  }
+
+  private additionalDependencies(): string[] {
+    const dependencies: string[] = []
+    const hasFunctions = this.configurations().some((c) => c.hasFunction)
+
+    if (hasFunctions) {
+      dependencies.push(this.MUSTACHE_IMPORT)
+    }
+
+    return dependencies
+  }
+
+  private generateAccessorMethods(): string[] {
+    const uniqueMethods: Record<string, string> = {}
+    const schemaTypes = this.configurations().map((config) => {
+      let methodName = camelCase(config.key)
+
+      // If the method name starts with a digit, prefix it with an underscore to ensure method name is valid
+      if (/^\d/.test(methodName)) {
+        methodName = `_${methodName}`
+      }
+
+      console.log(config.key, methodName)
+
+      if (uniqueMethods[methodName]) {
+        throw new Error(
+          `Method '${methodName}' is already registered. Prefab key ${config.key} conflicts with '${uniqueMethods[methodName]}'!`,
+        )
+      }
+
+      uniqueMethods[methodName] = config.key
+
+      if (config.hasFunction) {
+        const returnValue = new ZodToTypescriptReturnValueMapper().resolveType(config.schema)
+
+        return stripIndent`
+          ${methodName}(contexts?: Contexts | ContextObj): PrefabTypeGeneration.NodeServerConfigurationAccessor['${config.key}'] {
+                  const raw = this.get('${config.key}', contexts)
+                  return ${returnValue}
+                }
+          `
+      }
+
+      return stripIndent`
+        ${methodName}(contexts?: Contexts | ContextObj): PrefabTypeGeneration.NodeServerConfigurationAccessor['${config.key}'] {
+                return this.get('${config.key}', contexts)
+              }
+          `
+    })
+
+    return schemaTypes
+  }
+
+  private generateSchemaTypes(target: ZodToTypescriptMapperTarget = 'accessor'): string[] {
+    const schemaTypes = this.configurations().flatMap((config) => {
+      const mapper = new ZodToTypescriptMapper({fieldName: config.key, target})
+
+      return mapper.renderField(config.schema)
+    })
+
+    return schemaTypes
+  }
+}

src/codegen/code-generators/react-typescript-generator.ts

@@ -0,0 +1,123 @@
+import {stripIndent} from 'common-tags'
+import camelCase from 'lodash.camelcase'
+import {z} from 'zod'
+
+import {ZodToTypescriptMapper, type ZodToTypescriptMapperTarget} from '../language-mappers/zod-to-typescript-mapper.js'
+import {ZodToTypescriptReturnValueMapper} from '../language-mappers/zod-to-typescript-return-value-mapper.js'
+import {BaseTypescriptGenerator} from './base-typescript-generator.js'
+
+export class ReactTypeScriptGenerator extends BaseTypescriptGenerator {
+  get filename(): string {
+    return 'prefab-client.ts'
+  }
+
+  protected durationTypeMap(): z.ZodTypeAny {
+    return z.object({ms: z.number(), seconds: z.number()})
+  }
+
+  generate(): string {
+    return stripIndent`
+    /* eslint-disable */
+    // AUTOGENERATED by prefab-cli's 'gen' command
+    import { Prefab } from "@prefab-cloud/prefab-cloud-js"
+    import { createPrefabHook } from "@prefab-cloud/prefab-cloud-react"
+    ${this.additionalDependencies().join('\n') || '// No additional dependencies required'}
+
+    declare namespace PrefabTypeGeneration {
+      export type ReactHookConfigurationRaw = {
+        ${this.generateSchemaTypes('raw').join('\n        ') || '// No types generated'}
+      }
+
+      export type ReactHookConfigurationAccessor = {
+        ${this.generateSchemaTypes().join('\n        ') || '// No types generated'}
+      }
+    }
+
+    export class PrefabTypesafeReact {
+      constructor(private prefab: Prefab) { }
+
+      get<K extends keyof PrefabTypeGeneration.ReactHookConfigurationRaw>(key: K): PrefabTypeGeneration.ReactHookConfigurationRaw[K] {
+        return this.prefab.get(key) as PrefabTypeGeneration.ReactHookConfigurationRaw[K]
+      }
+
+      ${this.generateAccessorMethods().join('\n\n      ') || '// No methods generated'}
+    }
+
+    export const usePrefab = createPrefabHook(PrefabTypesafeReact)
+    `
+  }
+
+  private additionalDependencies(): string[] {
+    const dependencies: string[] = []
+    const hasFunctions = this.filteredConfigurations().some((c) => c.hasFunction)
+
+    if (hasFunctions) {
+      dependencies.push(this.MUSTACHE_IMPORT)
+    }
+
+    return dependencies
+  }
+
+  private filteredConfigurations() {
+    return this.configurations().filter(
+      (config) => config.configType === 'FEATURE_FLAG' || config.sendToClientSdk === true,
+    )
+  }
+
+  private generateAccessorMethods(): string[] {
+    const uniqueMethods: Record<string, string> = {}
+    const schemaTypes = this.filteredConfigurations().map((config) => {
+      let methodName = camelCase(config.key)
+
+      // If the method name starts with a digit, prefix it with an underscore to ensure method name is valid
+      if (/^\d/.test(methodName)) {
+        methodName = `_${methodName}`
+      }
+
+      if (uniqueMethods[methodName]) {
+        throw new Error(
+          `Method '${methodName}' is already registered. Prefab key ${config.key} conflicts with '${uniqueMethods[methodName]}'!`,
+        )
+      }
+
+      uniqueMethods[methodName] = config.key
+
+      if (config.configType === 'FEATURE_FLAG') {
+        return stripIndent`
+          get ${methodName}(): boolean {
+                  return this.prefab.isEnabled('${config.key}')
+                }
+          `
+      }
+
+      if (config.hasFunction) {
+        const returnValue = new ZodToTypescriptReturnValueMapper().resolveType(config.schema)
+
+        return stripIndent`
+          ${methodName}(): PrefabTypeGeneration.ReactHookConfigurationAccessor['${config.key}'] {
+                  const raw = this.get('${config.key}')
+                  return ${returnValue}
+                }
+          `
+      }
+
+      return stripIndent`
+        get ${methodName}(): PrefabTypeGeneration.ReactHookConfigurationAccessor['${config.key}'] {
+                return this.get('${config.key}')
+              }
+        `
+    })
+
+    return schemaTypes
+  }
+
+  private generateSchemaTypes(target: ZodToTypescriptMapperTarget = 'accessor'): string[] {
+    const schemaTypes = this.filteredConfigurations().map((config) => {
+      const mapper = new ZodToTypescriptMapper({fieldName: config.key, target})
+
+      return mapper.renderField(config.schema)
+    })
+
+    return schemaTypes
+  }
+}

src/codegen/language-mappers/json-to-zod-mapper.ts

@@ -0,0 +1,71 @@
+import {z} from 'zod'
+
+export class JsonToZodMapper {
+  resolve(data: unknown): z.ZodTypeAny {
+    if (Array.isArray(data)) {
+      if (data.length > 0) {
+        // Check if all elements in the array have the same type
+        const firstItem = data[0]
+
+        const isHomogeneous = data.every((item) => {
+          const itemsMatch = typeof item === typeof firstItem
+
+          // Special handling for objects and arrays
+          if (typeof firstItem === 'object') {
+            if (Array.isArray(item)) {
+              return Array.isArray(firstItem)
+            }
+
+            return !Array.isArray(firstItem)
+          }
+
+          return itemsMatch
+        })
+
+        // For homogeneous arrays, use the first element's type
+        if (isHomogeneous) {
+          return z.array(this.resolve(data[0]))
+        }
+
+        // Explicitly do not handle mixed-type arrays
+        // They could be tuples or heterogeneous arrays
+        // Instead, we return an array of unknowns
+      }
+
+      return z.array(z.unknown())
+    }
+
+    if (typeof data === 'object' && data !== null) {
+      const shape: Record<string, z.ZodTypeAny> = {}
+      const dataRecord = data as Record<string, unknown>
+      for (const key in dataRecord) {
+        if (Object.hasOwn(dataRecord, key)) {
+          shape[key] = this.resolve(dataRecord[key])
+        }
+      }
+
+      return z.object(shape)
+    }
+
+    if (typeof data === 'string') {
+      return z.string()
+    }
+
+    if (typeof data === 'number') {
+      return z.number()
+    }
+
+    if (typeof data === 'boolean') {
+      return z.boolean()
+    }
+
+    if (data === null) {
+      return z.null()
+    }
+
+    console.warn(`Unknown json type:`, data)
+
+    // If the type is not recognized, default to 'any'
+    return z.any()
+  }
+}