帮忙写typescript代码，动态按需加载typescript文件中的函数方法，根据json维护的顺序动态调用函数，不同函数传值个数不同，利用原子化，返回值类型也都不同

A：

可以借助ts-node实现动态加载ts文件。具体代码如下：

import * as ts from 'typescript';
import * as fs from 'fs';
import * as path from 'path';

interface FunctionParam {
  name: string;
  type?: string;
  required?: boolean;
}

interface Function {
  name: string;
  params?: FunctionParam[];
  returnType?: string;
}

function loadModule(modulePath: string, functionName: string): Function {
  const code = fs.readFileSync(modulePath).toString();
  const sourceFile = ts.createSourceFile(modulePath, code, ts.ScriptTarget.ESNext);

  const functionDeclaration = sourceFile.statements.find((node) => {
    if (!ts.isFunctionDeclaration(node)) {
      return false;
    }

    return node.name?.escapedText === functionName;
  }) as ts.FunctionDeclaration;

  const functionParams = functionDeclaration.parameters.map((parameter) => {
    const parameterSymbol = sourceFile.locals.get((parameter.name as ts.Identifier).escapedText);
    const parameterType = parameter.type ? code.slice(parameter.type.pos, parameter.type.end) : undefined;
    const parameterRequired = !(parameterQuestionToken && parameterQuestionToken.token === ts.SyntaxKind.QuestionToken);

    return {
      name: (parameter.name as ts.Identifier).escapedText.toString(),
      type: parameterType,
      required: parameterRequired,
    };
  });

  const returnTypeSymbol = functionDeclaration.symbol?.declarations?.[0]?.type;
  const returnType = returnTypeSymbol ? code.slice(returnTypeSymbol.pos, returnTypeSymbol.end) : undefined;

  return {
    name: functionName,
    params: functionParams,
    returnType,
  };
}

function invokeFunction(functionModule: string, functionName: string, params: any[]): any {
  const modulePath = path.resolve(__dirname, functionModule);
  const functionObject = loadModule(modulePath, functionName);

  // 校验参数个数
  if (params.length !== (functionObject.params?.length ?? 0)) {
    throw new Error('参数个数不匹配');
  }

  const paramObject: Record<string, any> = {};
  functionObject.params?.forEach((param, index) => {
    const paramValue = params[index];

    // 检验参数是否必须
    if (param.required && paramValue === undefined) {
      throw new Error(`参数${param.name}不能为空`);
    }

    // 检验参数类型
    if (param.type && typeof paramValue !== param.type) {
      throw new Error(`参数${param.name}类型不正确，期望为${param.type}`);
    }

    paramObject[param.name] = paramValue;
  });

  const functionPath = `${modulePath}#${functionName}`;
  const functionResult = invokeFunctionCache.getOrCreate(functionPath, () => {
    const functionModule = require(modulePath);
    const functionReference = functionModule[functionName] || functionModule.default || functionModule;

    return functionReference(...params);
  });

  // 检验返回值类型
  if (functionObject.returnType && typeof functionResult !== functionObject.returnType) {
    throw new Error(`返回值类型不正确，期望为${functionObject.returnType}`);
  }

  return functionResult;
}

interface InvokeFunctionCacheEntry {
  result: any;
  timestamp: number;
}

class InvokeFunctionCache {
  private readonly cache: Record<string, InvokeFunctionCacheEntry> = {};
  private readonly timeout: number;

  constructor(timeout?: number) {
    this.timeout = timeout ?? 5000;
  }

  public getOrCreate(key: string, createFunc: () => any): any {
    const cachedEntry = this.cache[key];
    const currentTime = Date.now();

    if (cachedEntry && currentTime - cachedEntry.timestamp < this.timeout) {
      return cachedEntry.result;
    } else {
      const result = createFunc();
      this.cache[key] = { result, timestamp: currentTime };

      return result;
    }
  }
}

const invokeFunctionCache = new InvokeFunctionCache();

[
  {
    "functionModule": "./function1.ts",
    "functionName": "function1",
    "args": [
      1,
      2
    ]
  },
  {
    "functionModule": "./function2.ts",
    "functionName": "function2",
    "args": [
      "hello"
    ]
  },
]

type Args = unknown[];

interface JsonFunction {
  functionModule: string;
  functionName: string;
  args: Args;
}

function main(jsonFunctions: JsonFunction[]): void {
  for (const jsonFunction of jsonFunctions) {
    const {functionModule, functionName, args} = jsonFunction;

    try {
      const result = invokeFunction(functionModule, functionName, args);
      console.log(`执行 ${functionName}(${args.join(', ')}) 结果为 ${result}`);
    } catch (err) {
      console.error(`执行 ${functionName}(${args.join(', ')}) 失败，原因为 ${err.message}`);
    }
  }
}

const jsonFunctions: JsonFunction[] = [
  {
    functionModule: './function1.ts',
    functionName: 'function1',
    args: [1, 2],
  },
  {
    functionModule: './function2.ts',
    functionName: 'function2',
    args: ['hello'],
  },
];

main(jsonFunctions);

在该代码中，我们通过loadModule函数加载ts文件，并从中获取需要执行的函数的参数数量和返回值类型等信息。然后，我们通过invokeFunction函数来执行函数，并做出必要的参数和返回值类型检查。最后，我们利用invokeFunctionCache来缓存函数的执行结果，以加快函数的重复执行速度。

最后，我们可以通过调用main函数来执行由JSON序列化的函数调用列表。