Error: ENOENT: no such file or directory, open When trying to access a directory with fs

Question

我不了解 nodejs 或 express，我在 http://localhost:3000 上有一个 API 运行并且端点之一调用使用文件系统读取文件的函数同步地。当我对 postman 发出 post 请求时，它在控制台中说它无法读取不存在的路径（据我所知）。

相关代码：

index.js

app.post('/write',(req,res)=>
{
    var body = req.body;
    console.log('endpoint reached');
    console.log(body);
    logic.append(body.key,body.path);
    res.send('Writting to state was successful');
});

stateLogic.js（这发生在第一次初始化 trieRoot 时）

async append(key,path)
    {
        var trieRoot = Buffer.from(programData.volatile.modularVariables.readSync(programData.persistent.paths.srcRoot,programData.volatile.modularVariables.encoding.utf8),'hex');

        console.log(trieRoot);

        var db = programData.persistent.states.singularity;
        var trie = new merkle_patricia_tree_1.SecureTrie(db,trieRoot);

        var data = programData.volatile.modularVariables.readSync(path,programData.volatile.modularVariables.encoding.utf8);

        var format = programData.volatile.modularVariables.getFormat(path);

        var name = programData.volatile.modularVariables.getName(path);

        var inData = JSON.stringify({name,format,data});
        

        console.log(`key: ${key} value: ${inData}`);

        await trie.put(Buffer.from(key),Buffer.from(inData));  

        var root = await trie.root; 

        programData.volatile.modularVariables.write(programData.persistent.paths.srcRoot,root.toString('hex'),programData.volatile.modularVariables.writeCB);

        var retGet = await trie.get(Buffer.from(key));

        console.log('Get returned:'+retGet.toString());
        console.log(`From Stack: ${root.toString('hex')} From File: ${this.malleableVar}`);

        return;
    };

使用的 readSync 函数：

readSync: (file,encoding)=>{return fs.readFileSync(file,{encoding:encoding,flag:'r'})},

使用的 srcRoot 值：

srcRoot: './storage/root.txt'

控制台错误：

(node:18808) UnhandledPromiseRejectionWarning: Error: ENOENT: no such file or directory, open './storage/root.txt'

路径：

问题：

为什么路径存在却说不存在？我做错了什么？谢谢你的时间。

Answer 1

您必须使用 absolute path 而不是 relative path

使用以下代码修改您的index.js：

const path = require('path') // <-- import path module to use absolute path.

app.post('/write',(req,res)=>
{
    var body = req.body;
    const absPath = path.join(__dirname, body.path); // <-- absolute path
    console.log("Absolute Path: ", absPath);
    logic.append(body.key, absPath);
    res.send('Writting to state was successful');
});

注意： 如果您仍然遇到同样的错误，请检查 body.path 值。

Answer 2

我们可以使用路径模块为目录提供绝对路径

folder
  |-server.js
  |-cert.pem

在 server.js 文件中

const const path = require('path') 
const certpath = path.join(__dirname,'chain.pem'); // folder\chain.pem

Error: ENOENT: no such file or directory, open When trying to access a directory with fs

Error: ENOENT: no such file or directory, open When trying to access a directory with fs

javascript

directory

node.js

express

server