为什么 createReadStream 函数发送损坏的文件？

Question

我正在使用 fs 模块从 url 生成一个文件到我的本地系统。希望是成功的。但是当我尝试使用 createReadStream() 函数将该文件 post 分组时，它向我发送了一个损坏的文件。

目前我尝试使用 excel 文件。

function saveFileToLocal(urlData,fileName){
    return new Promise ((res,rej) => {
        https.get(urlData, function(response) {
            if (response.statusCode === 200) {
                var file = fs.createWriteStream(path+`/controller/localmaping/files/${fileName}`)
                response.pipe(file);
                file.on('finish', function() {
                    file.close();  // close() is async
                });
                res('done')
            }
            else{
                rej('failed')
            }
    })
})
}

async function postAttachmentToGroup(groupid, senderId, text, urlData) {
    let fileName = urlData.substring(urlData.lastIndexOf('/') + 1).split("?")[0] // File name

    await saveFileToLocal(urlData,fileName)
    console.log(fileName)
    console.log(path)

    request({
        url: "https://graph.facebook.com/group_file_revisions",
        headers: { "Content-Type": "form-data","Authorization":"Bearer "+config.ACCESS_TOKEN },
        method: "POST",
        formData:{"file":fs.createReadStream(path+`/controller/localmaping/files/${fileName}`)}
    }, (err, res, body) => {
        if (!err) {
            let id = JSON.parse(body).id;
            let request_body = {
                "message": text + "\nPost by @[" + senderId + "]",
                "formatting":"MARKDOWN",
                "files": [ id ]
            }
        request({
            "uri": `https://graph.workplace.com/${groupid}/feed`,
            "qs": { "access_token": config.ACCESS_TOKEN },
            "method": "POST",
            "json": request_body
        }, (err, res, body) => {
            if (!err) {
                console.log(body)
                console.log('Post Success in feed!')
            }
            else {
                console.error("Unable to Post in feed" + err);
            }
        });
    }
    else {
        console.error("Unable to Post in feed" + err);
    }
    })
}

Answer 1

我通过添加回调函数解决了这个问题。还添加了在文件发送过程成功后从本地存储中删除文件的功能。

function postAttachmentToGroup(groupid, senderId, text, urlData) {
    let fileName = urlData.substring(urlData.lastIndexOf('/') + 1).split("?")[0]

    https.get(urlData, function(response) {
        if (response.statusCode === 200) {
            var file = fs.createWriteStream(path+`/controller/localmaping/files/${fileName}`)
            response.pipe(file);
            
            file.on('finish', function() {
                request({
                    url: "https://graph.facebook.com/group_file_revisions",
                    headers: { "Content-Type": "multipart/form-data","Authorization":"Bearer "+config.ACCESS_TOKEN },
                    method: "POST",
                    formData:{"file":fs.createReadStream(path+`/controller/localmaping/files/${fileName}`)}
                }, (err, res, body) => {
                    if (!err) {
                        let id = JSON.parse(body).id;
                        
                        console.log(id)
                
                        let request_body = {
                            "message": text + "\nPost by @[" + senderId + "]",
                            "formatting":"MARKDOWN",
                            "files": [ id ]
                        }
            
                        request({
                            "uri": `https://graph.workplace.com/${groupid}/feed`,
                            "qs": { "access_token": config.ACCESS_TOKEN },
                            "method": "POST",
                            "json": request_body
                        }, (err, res, body) => {
                            if (!err) {
                                console.log(body)
                                console.log('Post Success in feed!')
                                fs.unlink(path+`/controller/localmaping/files/${fileName}`,function (err){
                                    if(err){
                                        console.log("error in deleting file")
                                    }
                                    else{
                                        console.log("file deleted successfully")
                                    }
                                })
                            }
                            else {
                                console.error("Unable to Post in feed" + err);
                            }
                        });
                    }
                    else {
                        console.error("Unable to Post in feed" + err);
                    }
                })
            });
        }
        else{
            console.log('failed')
        }
    })
}

为什么 createReadStream 函数发送损坏的文件？

Why createReadStream function sending corrupt file?

javascript

fs

node.js

express