How can the server automatically interrupt the file transfer? #456
Description
Now I have a need, that is, you want to limit the number of customer-side upload files.
Assuming the server now want to limit the client can only upload a file, then it is possible to detect the client is the time to upload the first two files on the initiative to interrupt transmission ? This is just an example, as well as a single file size limit, file type, file extension, etc.
I read the API seems to filter only some of the files, although not stored in the file, but the client actually upload the file stream.
I was wondering if it was possible to take the initiative to throw a bit off the onprogress, onfileBegin, onfile, etc. interrupts the transfer and called onerror.
ps: Forgive me for not going to English, all Google Translate.
mart of my code:
/** 初始默认配置 */
const options = {
dir: null,
bytesExpected: 10 * 1024 * 1024,
maxFieldsSize: 2 * 1024 * 1024,
maxFields: 1000,
multiples: false,
hash: false,
fileNum: 1,
fileSize: 10 * 1024 * 1024,
fileType: null,
fileExt: null,
};
const getFormidable = async function (request, option) {
return new Promise(async (resolve, reject) => {
/** 初始化配置对象 */
if (utils.lodash.isUndefined(option)) {
option = {};
}
/** 检查配置对象 */
if (!utils.lodash.isPlainObject(option)) {
return throwError(new Error('${option} 必须是一个普通对象！'));
}
option = utils.lodash.merge(options, option);
let error = checkOption(options);
const throwError = function (err) {
request.pause();
error = err;
return reject(err);
};
if (utils.lodash.isError(error)) {
return throwError(error);
}
var form = new formidable.IncomingForm();
if (form.bytesExpected > option.bytesExpected) {
return throwError(new Error(`字节预期不可以超过${option.bytesExpected}字节！`));
}
form.encoding = 'utf-8';
if (uploadDir) form.uploadDir = utils.rootJoin(uploadDir);
form.keepExtensions = false;
// form.type = 'multipart';
form.maxFieldsSize = option.maxFieldsSize;
form.maxFields = option.maxFields;
form.multiples = option.multiples;
form.hash = option.hash;
let fileNum = 0;
form.onPart = function (part) {
if (option.fileNum) {
if (part.filename) { fileNum += 1; }
if (fileNum > option.fileNum) {
return throwError(new Error(`上传文件数量不可以超过${option.fileNum}个！`));
}
}
if (option.fileExt && !option.fileExt.includes(utils.path.extname(part.filename))) {
return throwError(new Error(`上传文件后缀名必须是(${option.fileExt})！`));
}
form.handlePart(part);
};
form.on('progress', function (bytesReceived, bytesExpected) {
if (bytesExpected > option.bytesExpected) {
return throwError(new Error(`字节预期不可以超过${option.bytesExpected}字节！`));
}
});
// form.on('field', function (name, value) { });
form.on('fileBegin', function (name, file) {
if (option.fileType && !option.fileType.includes(file.type)) {
return throwError(new Error(`上传文件类型必须是(${option.fileType})！`));
}
});
form.on('file', function (name, file) {
if (file.size > option.fileSize) {
return throwError(new Error(`上传文件大小不可以超过${option.fileSize}字节！`));
}
});
form.on('error', function (err) {
return throwError(err);
});
form.on('aborted', function () {
return throwError(new Error(`当前请求被用户发出中止时！`));
});
// form.on('end', function () { });
form.parse(request, function (err, fields, files) {
if (err) return throwError(err);
if (error) return throwError(error);
return resolve({ fields, files });
});
});
};