swift - Vapor 一次上传多个文件

Question

我想在一个 POST 请求中上传多张图片。目前，我的请求中与文件上传相关的部分正在获取一个文件，如下所示:

return try req.content.decode(File.self).flatMap(to: Image.self) { (file) in
    try file.data.write(to: URL(fileURLWithPath: DirectoryConfig.detect().workDir + localImageStorage + file.filename))
    return try Image(userID: user.requireID(), url: imageStorage + file.filename, filename: file.filename).save(on: req)
}

这很好用。现在，我尝试将 .decode(File.self) 更改为 .decode([File].self)，并对所有文件进行循环。
尝试在 Postman 中使用 data[] 参数上传图片时，出现以下错误:

Nested form-data decoding is not supported.

我该如何解决？

Answer 1

下面的例子效果很好，已经测试了多次 🙂

struct MyPayload: Content {
    var somefiles: [File]
}

func myUpload(_ req: Request) -> Future<HTTPStatus> {
    let user: User = try req.requireAuthenticated()
    return try req.content.decode(MyPayload.self).flatMap { payload in
        let workDir = DirectoryConfig.detect().workDir
        return payload.somefiles.map { file in
            let url = URL(fileURLWithPath: workDir + localImageStorage + file.filename)
            try file.data.write(to: url)
            return try Image(userID: user.requireID(), url: imageStorage + file.filename, filename: file.filename).save(on: req).transform(to: ())
        }.flatten(on: req).transform(to: .ok)
    }
}

顺便说一句，您也可以在函数参数中准确声明您的有效载荷

func myUpload(_ req: Request, _ payload: MyPayload) -> Future<HTTPStatus> {
    let user: User = try req.requireAuthenticated()
    let workDir = DirectoryConfig.detect().workDir
    return payload.somefiles.map { file in
        let url = URL(fileURLWithPath: workDir + localImageStorage + file.filename)
        try file.data.write(to: url)
        return try Image(userID: user.requireID(), url: imageStorage + file.filename, filename: file.filename).save(on: req).transform(to: ())
    }.flatten(on: req).transform(to: .ok)
}

唯一的区别在于在路由器上声明端点​​函数

router.post("upload", use: myUpload)

对比

router.post(MyPayload.self, at: "upload", use: myUpload)

然后在 Postman 中像这样上传你的文件