Android REST API客户端，允许http POST的文件附件

Question

是否有人知道Android应用程序充当REST API客户端并允许附加文件？我希望在Postman中做相同的操作，但是来自Android设备：

我在Google Play上尝试过“REST Client for Android”和“HTTP Client”，但这些似乎只允许正文中的文字，而不是文件附件。任何人都可以为Android目前的选项提供建议吗？

Answer 1

https://futurestud.io/blog/retrofit-2-how-to-upload-files-to-server

请找到改造api的上述链接，主要使用restapi。

Answer 2

使用HttpURLConnection类在服务器上上传图像。

String urlStr= "url link";
String response;
boolean isGetMethod = false;
private class HttpAsyncTask extends AsyncTask<String, Void, String> {

    @Override
    protected String doInBackground(String... params) {

        DataOutputStream dataOutputStream;
        String lineEnd = "\r\n", twoHyphens = "--", boundary = "*****";
        int bytesRead, bytesAvailable, bufferSize;
        byte[] buffer;
        File file;
        int maxBufferSize = 1024 * 1024;
        FileInputStream fileInputStream;

        try {
            URL url = new URL(urlStr);

            httpURLConnection = (HttpURLConnection) url.openConnection();

            if (!isGetMethod) {

                httpURLConnection.setRequestMethod("POST");
                httpURLConnection.setDoOutput(true);
                httpURLConnection.setDoInput(true);
                httpURLConnection.setUseCaches(false);
                httpURLConnection.setRequestProperty("Connection", "Keep-Alive");
                httpURLConnection.setRequestProperty("ENCTYPE", "multipart/form-data");
                httpURLConnection.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);

                dataOutputStream = new DataOutputStream(httpURLConnection.getOutputStream());

                file = new File("image file path");
                fileInputStream = new FileInputStream(file);

                dataOutputStream.writeBytes(twoHyphens + boundary + lineEnd);
                dataOutputStream.writeBytes("Content-Disposition: form-data; name=\"" + key + "\"; filename=\"" + file.getName() + "\"" + lineEnd);
                dataOutputStream.writeBytes("Content-Type: image/jpeg" + lineEnd);
                dataOutputStream.writeBytes("Content-Transfer-Encoding: binary" + lineEnd);
                dataOutputStream.writeBytes(lineEnd);

                bytesAvailable = fileInputStream.available();
                bufferSize = Math.min(bytesAvailable, maxBufferSize);
                buffer = new byte[bufferSize];

                bytesRead = fileInputStream.read(buffer, 0, bufferSize);
                while (bytesRead > 0) {
                    dataOutputStream.write(buffer, 0, bufferSize);
                    bytesAvailable = fileInputStream.available();
                    bufferSize = Math.min(bytesAvailable, maxBufferSize);
                    bytesRead = fileInputStream.read(buffer, 0, bufferSize);
                }

                // send multipart form data necesssary after file data...

                dataOutputStream.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
                dataOutputStream.flush();
                dataOutputStream.close();
            }

            if (httpURLConnection.getResponseCode() == HttpURLConnection.HTTP_OK) {
                BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(httpURLConnection.getInputStream()));
                String inputLine;
                StringBuilder builder = new StringBuilder();
                while ((inputLine = bufferedReader.readLine()) != null) {
                    builder.append(inputLine);
                }
                response = builder.toString();
                bufferedReader.close();
            } else
                return response;

        } catch (Exception e) {
           e.printStackTrace();
        }

        httpURLConnection.disconnect();
        return response;
    }

    @Override
    protected void onPostExecute(String response) {
    }
}