Javascript 如何从NodeJSAPI返回zip文件并在客户端处理?
我有一个API,它使用archiver模块创建一个zip文件,我想在其中将zip作为响应传递回客户端并下载它 这就是我创建zip的API的样子:Javascript 如何从NodeJSAPI返回zip文件并在客户端处理?,javascript,node.js,Javascript,Node.js,我有一个API,它使用archiver模块创建一个zip文件,我想在其中将zip作为响应传递回客户端并下载它 这就是我创建zip的API的样子: reports.get('/xxx/:fileName', async (req, res) => { var s3 = new AWS.S3(); var archiver = require('archiver'); var filenames = "xxx" var str_array = filenames.split
reports.get('/xxx/:fileName', async (req, res) => {
var s3 = new AWS.S3();
var archiver = require('archiver');
var filenames = "xxx"
var str_array = filenames.split(',');
for (var i = 0; i < str_array.length; i++) {
var filename = str_array[i].trim();
localFileName = './temp/' + filename.substring(filename.indexOf("/") + 1);
file = fs.createWriteStream(localFileName, {flags: 'a', encoding: 'utf-8',mode: 0666});
file.on('error', function(e) { console.error(e); });
s3.getObject({
Bucket: config.xxx,
Key: filename
})
.on('error', function (err) {
console.log(err);
})
.on('httpData', function (chunk) {
file.on('open', function(){
file.write(chunk);
});
})
.on('httpDone', function () {
file.end();
})
.send();
}
res.end("Files have been downloaded successfully")
// create a file to stream archive data to.
var output = fs.createWriteStream('example.zip');
var archive = archiver('zip', {
zlib: { level: 9 } // Sets the compression level.
});
// listen for all archive data to be written
// 'close' event is fired only when a file descriptor is involved
output.on('close', function() {
console.log(archive.pointer() + ' total bytes');
console.log('archiver has been finalized and the output file descriptor has closed.');
});
// This event is fired when the data source is drained no matter what was the data source.
// It is not part of this library but rather from the NodeJS Stream API.
// @see: https://nodejs.org/api/stream.html#stream_event_end
output.on('end', function() {
console.log('Data has been drained');
});
// good practice to catch warnings (ie stat failures and other non-blocking errors)
archive.on('warning', function(err) {
if (err.code === 'ENOENT') {
// log warning
} else {
// throw error
throw err;
}
});
// good practice to catch this error explicitly
archive.on('error', function(err) {
throw err;
});
// pipe archive data to the file
archive.pipe(output);
// append files from a sub-directory, putting its contents at the root of archive
archive.directory('./temp', false);
// finalize the archive (ie we are done appending files but streams have to finish yet)
// 'close', 'end' or 'finish' may be fired right after calling this method so register to them beforehand
archive.finalize();
});
如何将zip作为响应发送回客户端并将其下载到磁盘?由于
archive
是流式传输,我假设它可以通过管道(内衬)直接发送到响应(res
):
//Node.js v10+,如果res是正确的流
const{pipeline}=require('stream')
管道(存档,res)
//或者(搜索管道与管道的注意事项)
档案.管道(res)
您可能应该在res
上设置一些HTTP头,以告知浏览器MIME类型以及可能的文件名:
res.set({
“内容类型”:“应用程序/zip”,
“内容处置”:“附件;文件名=“filename.jpg””
})
好的,所以一旦您编写了文件,example.zip
您就可以轻松地按照中提到的示例进行操作:
这应该能很好地发挥作用。归功于?我明白你的意思,但我该怎么做?用一些例子更新了我的答案。好的,我该如何处理客户端的响应?我通常在响应中使用res.json,但是对于zip来说这应该是不同的。此问题和代码的参考:
reports.get('/xxx/:fileName', async (req, res) => {
var s3 = new AWS.S3();
var params = {
Bucket: config.reportBucket,
Key: req.params.fileName,
Expires: 60 * 5
}
try {
s3.getSignedUrl('getObject', params, function (err, url) {
if(err)throw err;
res.json(url);
});
}catch (err) {
res.status(500).send(err.toString());
}
});
var stat = fileSystem.statSync('example.zip');
res.writeHead(200, {
'Content-Type': 'application/zip',
'Content-Length': stat.size
});
var readStream = fileSystem.createReadStream('example.zip');
// We replaced all the event handlers with a simple call to readStream.pipe()
readStream.pipe(res);