使用 Micronaut 下载文件

Download File with Micronaut

我的客户应该从控制器收到一个文件。问题是客户端只收到一个字符串。如何从控制器获取返回的流?

这是我的控制器:

@Get("/{databaseName}")
MutableHttpResponse < Object > createDatabaseBackup(String databaseName) {
    InputStream inputStreamDatabaseBackup = backupTask.exportBackup(databaseName);
    return HttpResponse.ok(new StreamedFile(inputStreamDatabaseBackup, MediaType.APPLICATION_OCTET_STREAM_TYPE));
}

这是我的客户:

@Inject
@Client("${agent.connection-url}")
private RxHttpClient client;

public String getBackup(String dataBaseName) {
    return client.toBlocking().retrieve(HttpRequest.GET("/backup/" + dataBaseName));
}

您必须将您需要的响应定义为 byte[] 数组:

public byte[] getBackup(String databaseName) {
    return client.toBlocking().retrieve(HttpRequest.GET("/backup/" + databaseName), byte[].class);
}

然后你可以将byte数组转换成你想要的任何流。

或者你可以使用响应方式:

public Single<byte[]> getBackup(String databaseName) {
    return client.retrieve(HttpRequest.GET("/backup/" + databaseName), byte[].class)
        .collect(ByteArrayOutputStream::new, ByteArrayOutputStream::writeBytes)
        .map(ByteArrayOutputStream::toByteArray);
}

或者您可以定义声明式客户端:

@Client("${agent.connection-url}")
public interface SomeControllerClient {

    @Get(value = "/{databaseName}", processes = MediaType.APPLICATION_OCTET_STREAM)
    Flowable<byte[]> getBackup(String databaseName);

}

然后在需要的地方使用它:

@Inject
SomeControllerClient client;

public void someMethod() {
    client.getBackup("some-database")
        .collect(ByteArrayOutputStream::new, ByteArrayOutputStream::writeBytes)
        .map(ByteArrayOutputStream::toByteArray)
        .otherStreamProcessing...
}