Use a presigned URL to upload a file - Object Storage Service

By default, the access control list (ACL) of an object in an Object Storage Service (OSS) bucket is private, and only the object owner has the permissions to access the object. You can use OSS SDK for Go to generate a presigned URL, which you can then share with a user to allow them to upload an object. When you generate the presigned URL, you can specify its validity period to limit the time during which the user can upload the object. During the validity period of the presigned URL, the user can use the URL to upload an object to the bucket multiple times. After the validity period of the presigned URL ends, the user can no longer use the presigned URL to upload an object. To prolong access for the user, regenerate a presigned URL.

Usage notes

In this topic, the public endpoint of the China (Hangzhou) region is used. To access OSS from other Alibaba Cloud services in the same region, use an internal endpoint. For details about supported regions and endpoints, see Regions and endpoints.
In this topic, access credentials are obtained from environment variables. For more information about how to configure access credentials, see Configure access credentials.
In this topic, an OSSClient instance is created by using an OSS endpoint. If you want to create an OSSClient instance by using custom domain names or Security Token Service (STS), see Configuration examples for common scenarios.
You do not need specific permissions to generate a presigned URL. However, to allow others to use the presigned URL for uploading an object, you must have the oss:PutObject permission. For more information, see Authorize a RAM user to access multiple directories in a bucket.
In this topic, the signature algorithm V4 is used to generate presigned URLs with a validity period of up to 7 days. For more information, see (Recommended) V4 signatures in presigned URLs.

Process

The following figure shows how to use a presigned URL that allows HTTP PUT requests to upload a file to OSS.

Use a presigned URL for a simple upload

The object owner generates a presigned URL that allows HTTP PUT requests.

package main

import (
	"log"

	"github.com/aliyun/aliyun-oss-go-sdk/oss"
)

func main() {
	// Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
	provider, err := oss.NewEnvironmentVariableCredentialsProvider()
	if err != nil {
		log.Printf("Error: %v", err)
	}

	// Create an OSSClient instance. 
	// Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.  
	// Specify the region of the bucket. For example, if your bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.  
	clientOptions := []oss.ClientOption{oss.SetCredentialsProvider(&provider)}
	clientOptions = append(clientOptions, oss.Region("cn-hangzhou"))
	// Specify the signature algorithm version.
	clientOptions = append(clientOptions, oss.AuthVersion(oss.AuthV4))
	client, err := oss.New("https://oss-cn-hangzhou.aliyuncs.com", "", "", clientOptions...)
	if err != nil {
		log.Printf("Error: %v", err)
	}

	// Specify the name of the bucket. Example: examplebucket. 
	bucketName := "examplebucket"
	// Specify the full path of the object. Example: exampleobject.txt. Do not include the bucket name in the full path. 
	objectName := "exampleobject.txt"
	bucket, err := client.Bucket(bucketName)
	if err != nil {
		log.Printf("Error: %v", err)
	}

	// Generate a presigned URL and set the validity period of the presigned URL to 600 seconds. 
	signedURL, err := bucket.SignURL(objectName, oss.HTTPPut, 600)
	if err != nil {
		log.Printf("Error: %v", err)
	}
	log.Printf("Sign Url:%s\n", signedURL)
}

A user uses the presigned URL to upload a local file.

curl

curl -X PUT -T /path/to/local/file "https://exampleobject.oss-cn-hangzhou.aliyuncs.com/exampleobject.txt?x-oss-date=20241112T083238Z&x-oss-expires=3599&x-oss-signature-version=OSS4-HMAC-SHA256&x-oss-credential=LTAI****************%2F20241112%2Fcn-hangzhou%2Foss%2Faliyun_v4_request&x-oss-signature=ed5a******************************************************"

Java

import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPut;
import org.apache.http.entity.FileEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import java.io.*;
import java.net.URL;
import java.util.*;

public class SignUrlUpload {
    public static void main(String[] args) throws Throwable {
        CloseableHttpClient httpClient = null;
        CloseableHttpResponse response = null;

        // Replace <signedUrl> with the presigned URL. 
        URL signedUrl = new URL("<signedUrl>");

        // Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
        String pathName = "C:\\Users\\demo.txt";

        try {
            HttpPut put = new HttpPut(signedUrl.toString());
            System.out.println(put);
            HttpEntity entity = new FileEntity(new File(pathName));
            put.setEntity(entity);
            httpClient = HttpClients.createDefault();
            response = httpClient.execute(put);

            System.out.println("Status code:"+response.getStatusLine().getStatusCode());
            if(response.getStatusLine().getStatusCode() == 200){
                System.out.println("The object is uploaded by using the library.");
            }
            System.out.println(response.toString());
        } catch (Exception e){
            e.printStackTrace();
        } finally {
            response.close();
            httpClient.close();
        }
    }
}

Go

package main

import (
	"fmt"
	"io"
	"net/http"
	"os"
)

func uploadFile(signedUrl, filePath string) error {
	// Open the local file.
	file, err := os.Open(filePath)
	if err != nil {
		return fmt.Errorf("Unable to open the local file: %w", err)
	}
	defer file.Close()

	// Create an HTTP client.
	client := &http.Client{}

	// Create a PUT request.
	req, err := http.NewRequest("PUT", signedUrl, file)
	if err != nil {
		return fmt.Errorf("Failed to create the request: %w", err)
	}

	// Send the request.
	resp, err := client.Do(req)
	if err != nil {
		return fmt.Errorf("Failed to send the request:: %w", err)
	}
	defer resp.Body.Close()

	// Read the response.
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return fmt.Errorf("Failed to read the request: %w", err)
	}

	fmt.Printf("Status code: %d\n", resp.StatusCode)
	if resp.StatusCode == 200 {
		fmt.Println("The object is uploaded by using the library.")
	}
	fmt.Println(string(body))

	return nil
}

func main() {
	// Replace <signedUrl> with the presigned URL. 
	signedUrl := "<signedUrl>"

	// Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
	filePath := "C:\\Users\\demo.txt"

	err := uploadFile(signedUrl, filePath)
	if err != nil {
		fmt.Println("An error occurred: ", err)
	}
}

python

import requests

def upload_file(signed_url, file_path):
    try:
        # Open the local file that you want to upload.
        with open(file_path, 'rb') as file:
            # Send a PUT request to upload the local file.
            response = requests.put(signed_url, data=file)
     
        print(f"Status code: {response.status_code}")
        if response.status_code == 200:
            print("The object is uploaded by using the library.")
        print(response.text)
 
    except Exception as e:
        print(f"An error occurred: {e}")

if __name__ == "__main__":
    # Replace <signedUrl> with the generated signed URL. 
    signed_url = "<signedUrl>"
    
    # Specify the full path of the local file. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
    file_path = "C:\\Users\\demo.txt"

    upload_file(signed_url, file_path)

Node.js

const fs = require('fs');
const axios = require('axios');

async function uploadFile(signedUrl, filePath) {
    try {
        // Create a read stream.
        const fileStream = fs.createReadStream(filePath);
        
        // Send a PUT request to upload the local file.
        const response = await axios.put(signedUrl, fileStream, {
            headers: {
                'Content-Type': 'application/octet-stream' // Specify the Content-Type parameter.
            }
        });

        console.log(`Status code: ${response.status}`);
        if (response.status === 200) {
            console.log("The object is uploaded by using the library.");
        }
        console.log(response.data);
    } catch (error) {
        console.error(`An error occurred: ${error.message}`);
    }
}

// Specify the main function.
(async () => {
    // Replace <signedUrl> with the presigned URL. 
    const signedUrl = '<signedUrl>';
    
    // Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
    const filePath = 'C:\\Users\\demo.txt';

    await uploadFile(signedUrl, filePath);
})();

browser.js

Important

When uploading an object using Browser.js and a presigned URL, a 403 SignatureNotMatch error that indicates signature inconsistency may occur. This is typically caused by the browser's automatic inclusion of the Content-Type request header, which that was not specified when the presigned URL was generated. To prevent this error, ensure that the Content-Type header is specified when generating a presigned URL.

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>File Upload Example</title>
</head>
<body>
    <h1>File Upload Example</h1>

    <! -- Select File -->
    <input type="file" id="fileInput" />
    <button id="uploadButton">Upload File</button>

    <script>
        // Replace <signedUrl> with the presigned URL that was generated in Step 1. 
        const signedUrl = "<signedUrl>"; 


        document.getElementById('uploadButton').addEventListener('click', async () => {
            const fileInput = document.getElementById('fileInput');
            const file = fileInput.files[0];

            if (!file) {
                alert('Please select a file to upload.');
                return;
            }

            try {
                await upload(file, signedUrl);
                alert('File uploaded successfully!');
            } catch (error) {
                console.error('Error during upload:', error);
                alert('Upload failed: ' + error.message);
            }
        });

        /**
         * Upload a file to OSS.
         * @param {File} file - The file to be uploaded.
         * @param {string} presignedUrl - The presigned URL.
         */
        const upload = async (file, presignedUrl) => {
            const response = await fetch(presignedUrl, {
                method: 'PUT',
                body: file,  // Upload the entire file.
            });

            if (!response.ok) {
                throw new Error(`Upload failed, status: ${response.status}`);
            }

            console.log('File uploaded successfully');
        };
    </script>
</body>
</html>

C#

using System.Net.Http.Headers;

// Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
var filePath = "C:\\Users\\demo.txt";
// Replace <signedUrl> with the presigned URL.
var presignedUrl = "<signedUrl>";

// Create an HTTP client and a local file stream.
using var httpClient = new HttpClient(); 
using var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
using var content = new StreamContent(fileStream);
            
// Create a PUT request.
var request = new HttpRequestMessage(HttpMethod.Put, presignedUrl);
request.Content = content;

// Send a request.
var response = await httpClient.SendAsync(request);

// Process the response.
if (response.IsSuccessStatusCode)
{
    Console.WriteLine($"Uploaded! Status Code: {response.StatusCode}");
    Console.WriteLine("Response Header:");
    foreach (var header in response.Headers)
    {
        Console.WriteLine($"{header.Key}: {string.Join(", ", header.Value)}");
    }
}
else
{
    string responseContent = await response.Content.ReadAsStringAsync();
    Console.WriteLine($"Upload Failed! Status Code: {response.StatusCode}");
    Console.WriteLine("Response content: " + responseContent);
}

C++

#include <iostream>
#include <fstream>
#include <curl/curl.h>

void uploadFile(const std::string& signedUrl, const std::string& filePath) {
    CURL *curl;
    CURLcode res;

    curl_global_init(CURL_GLOBAL_DEFAULT);
    curl = curl_easy_init();

    if (curl) {
        // Specify the presigned URL.
        curl_easy_setopt(curl, CURLOPT_URL, signedUrl.c_str());

        // Set the request method to PUT.
        curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);

        // Open the local file.
        FILE *file = fopen(filePath.c_str(), "rb");
        if (!file) {
            std::cerr << "Unable to open the file: " << filePath << std::endl;
            return;
        }

        // Query the size of the local file.
        fseek(file, 0, SEEK_END);
        long fileSize = ftell(file);
        fseek(file, 0, SEEK_SET);

        // Specify the size of the local file.
        curl_easy_setopt(curl, CURLOPT_INFILESIZE_LARGE, (curl_off_t)fileSize);

        // Specify the input file handle.
        curl_easy_setopt(curl, CURLOPT_READDATA, file);

        // Execute the request.
        res = curl_easy_perform(curl);

        if (res != CURLE_OK) {
            std::cerr << "curl_easy_perform() failed: " << curl_easy_strerror(res) << std::endl;
        } else {
            long httpCode = 0;
            curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &httpCode);
            std::cout << "Status code: " << httpCode << std::endl;

            if (httpCode == 200) {
                std::cout << "The object is uploaded by using the network library." << std::endl;
            }
        }

        // Close the local file.
        fclose(file);

        // Clear the cURL handle.
        curl_easy_cleanup(curl);
    }

    curl_global_cleanup();
}

int main() {
    // Replace <signedUrl> with the presigned URL. 
    std::string signedUrl = "<signedUrl>";

    // Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
    std::string filePath = "C:\\Users\\demo.txt";

    uploadFile(signedUrl, filePath);

    return 0;
}

Android

package com.example.signurlupload;

import android.os.AsyncTask;
import android.util.Log;

import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.URL;

public class SignUrlUploadActivity {

    private static final String TAG = "SignUrlUploadActivity";

    public void uploadFile(String signedUrl, String filePath) {
        new UploadTask().execute(signedUrl, filePath);
    }

    private class UploadTask extends AsyncTask<String, Void, String> {

        @Override
        protected String doInBackground(String... params) {
            String signedUrl = params[0];
            String filePath = params[1];

            HttpURLConnection connection = null;
            DataOutputStream dos = null;
            FileInputStream fis = null;

            try {
                URL url = new URL(signedUrl);
                connection = (HttpURLConnection) url.openConnection();
                connection.setRequestMethod("PUT");
                connection.setDoOutput(true);
                connection.setRequestProperty("Content-Type", "application/octet-stream");

                fis = new FileInputStream(filePath);
                dos = new DataOutputStream(connection.getOutputStream());

                byte[] buffer = new byte[1024];
                int length;

                while ((length = fis.read(buffer)) != -1) {
                    dos.write(buffer, 0, length);
                }

                dos.flush();
                dos.close();
                fis.close();

                int responseCode = connection.getResponseCode();
                Log.d(TAG, "Status code: " + responseCode);

                if (responseCode == 200) {
                    Log.d(TAG, "The object is uploaded by using the library.");
                }

                return "Object uploaded. Status code: " + responseCode;

            } catch (IOException e) {
                e.printStackTrace();
                return "Upload failed: " + e.getMessage();
            } finally {
                if (connection != null) {
                    connection.disconnect();
                }
            }
        }

        @Override
        protected void onPostExecute(String result) {
            Log.d(TAG, result);
        }
    }

    public static void main(String[] args) {
        SignUrlUploadActivity activity = new SignUrlUploadActivity();
        // Replace <signedUrl> with the presigned URL. 
        String signedUrl = "<signedUrl>";
        // Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
        String filePath = "C:\\Users\\demo.txt";
        activity.uploadFile(signedUrl, filePath);
    }
}

Common scenarios

Use a presigned URL that contains specific request headers and user metadata to upload a file

The object owner generates a presigned URL that contains specific request headers and user metadata and allows HTTP PUT requests.

package main

import (
	"log"

	"github.com/aliyun/aliyun-oss-go-sdk/oss"
)

func main() {
	// Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
	provider, err := oss.NewEnvironmentVariableCredentialsProvider()
	if err != nil {
		log.Printf("Error: %v", err)
	}

	// Create an OSSClient instance. 
	// Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.  
	// Specify the region of the bucket. For example, if your bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.  
	clientOptions := []oss.ClientOption{oss.SetCredentialsProvider(&provider)}
	clientOptions = append(clientOptions, oss.Region("cn-hangzhou"))
	// Specify the signature algorithm version.
	clientOptions = append(clientOptions, oss.AuthVersion(oss.AuthV4))
	client, err := oss.New("https://oss-cn-hangzhou.aliyuncs.com", "", "", clientOptions...)
	if err != nil {
		log.Printf("Error: %v", err)
	}

	// Specify the name of the bucket. Example: examplebucket. 
	bucketName := "examplebucket"
	// Specify the full path of the object. Example: exampleobject.txt. Do not include the bucket name in the full path. 
	objectName := "exampleobject.txt"
	bucket, err := client.Bucket(bucketName)
	if err != nil {
		log.Printf("Error: %v", err)
	}
	// Note that when you use a presigned URL that contains custom parameters on the frontend, you must specify the same content type as the one that is specified here to generate the presigned URL. 
	options := []oss.Option{
		oss.Meta("key1", "value1"),
		oss.Meta("key2", "value2"),
		oss.ContentType("text/plain; charset=utf8"),
	}

	// Generate a presigned URL and set the validity period of the presigned URL to 600 seconds. 
	signedURL, err := bucket.SignURL(objectName, oss.HTTPPut, 600, options...)
	if err != nil {
		log.Printf("Error: %v", err)
	}
	log.Printf("Sign Url:%s\n", signedURL)
}

A user uses the presigned URL to upload a local file.

curl

curl -X PUT \
     -H "Content-Type: text/plain;charset=utf8" \
     -H "x-oss-storage-class: Standard" \
     -H "x-oss-meta-key1: value1" \
     -H "x-oss-meta-key2: value2" \
     -T "C:\\Users\\demo.txt" \
     "https://exampleobject.oss-cn-hangzhou.aliyuncs.com/exampleobject.txt?x-oss-date=20241112T083238Z&x-oss-expires=3599&x-oss-signature-version=OSS4-HMAC-SHA256&x-oss-credential=LTAI****************%2F20241112%2Fcn-hangzhou%2Foss%2Faliyun_v4_request&x-oss-signature=ed5a******************************************************"

Java

import com.aliyun.oss.internal.OSSHeaders;
import com.aliyun.oss.model.StorageClass;
import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPut;
import org.apache.http.entity.FileEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import java.io.*;
import java.net.URL;
import java.util.*;

public class SignUrlUpload {
    public static void main(String[] args) throws Throwable {
        CloseableHttpClient httpClient = null;
        CloseableHttpResponse response = null;

        // Replace <signedUrl> with the presigned URL. 
        URL signedUrl = new URL("<signedUrl>");

        // Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
        String pathName = "C:\\Users\\demo.txt";

        // Specify request headers. Make sure that the values of the request headers are the same as those specified when the presigned URL was generated. 
        Map<String, String> headers = new HashMap<String, String>();
        // Specify the storage class of the object. 
        headers.put(OSSHeaders.STORAGE_CLASS, StorageClass.Standard.toString());
        // Specify the content type. 
        headers.put(OSSHeaders.CONTENT_TYPE, "text/plain;charset=utf8");

        // Specify user metadata. Make sure that the user metadata here is the same as the user metadata specified when the presigned URL was generated. 
        Map<String, String> userMetadata = new HashMap<String, String>();
        userMetadata.put("key1","value1");
        userMetadata.put("key2","value2");

        try {
            HttpPut put = new HttpPut(signedUrl.toString());
            System.out.println(put);
            HttpEntity entity = new FileEntity(new File(pathName));
            put.setEntity(entity);
            // If you configure headers such as the user metadata and storage class when the presigned URL was generated, these headers must be sent to the server when the presigned URL is used to upload a file. If the headers that are sent to the server for the signature calculation are different from the headers specified when the presigned URL was generated, a signature error is reported. 
            for(Map.Entry header: headers.entrySet()){
                put.addHeader(header.getKey().toString(),header.getValue().toString());
            }
            for(Map.Entry meta: userMetadata.entrySet()){
                // If user metadata is specified, the SDK adds the "x-oss-meta-" prefix to the user metadata key. If you use other methods to upload a file, make sure that the "x-oss-meta-" prefix is also added to the user metadata key. 
                put.addHeader("x-oss-meta-"+meta.getKey().toString(), meta.getValue().toString());
            }

            httpClient = HttpClients.createDefault();

            response = httpClient.execute(put);

            System.out.println("Status code of the upload: "+response.getStatusLine().getStatusCode());
            if(response.getStatusLine().getStatusCode() == 200){
                System.out.println("The object is uploaded by using the library.");
            }
            System.out.println(response.toString());
        } catch (Exception e){
            e.printStackTrace();
        } finally {
            response.close();
            httpClient.close();
        }
    }
}

Go

package main

import (
	"bytes"
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
)

func uploadFile(signedUrl string, filePath string, headers map[string]string, metadata map[string]string) error {
	// Open the local file.
	file, err := os.Open(filePath)
	if err != nil {
		return err
	}
	defer file.Close()

	// Read the object content.
	fileBytes, err := ioutil.ReadAll(file)
	if err != nil {
		return err
	}

	// Create a request.
	req, err := http.NewRequest("PUT", signedUrl, bytes.NewBuffer(fileBytes))
	if err != nil {
		return err
	}

	// Specify request headers.
	for key, value := range headers {
		req.Header.Set(key, value)
	}

	// Specify user metadata.
	for key, value := range metadata {
		req.Header.Set(fmt.Sprintf("x-oss-meta-%s", key), value)
	}

	// Send a request.
	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	// Process the response.
	fmt.Printf("Status code: %d\n", resp.StatusCode)
	if resp.StatusCode == 200 {
		fmt.Println("The object is uploaded by using the library.")
	} else {
		fmt.Println("Upload failed")
	}
	body, _ := ioutil.ReadAll(resp.Body)
	fmt.Println(string(body))

	return nil
}

func main() {
	// Replace <signedUrl> with the presigned URL. 
	signedUrl := "<signedUrl>"

	// Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
	filePath := "C:\\Users\\demo.txt"

	// Specify request headers. Make sure that the values of the request headers are the same as those specified when the presigned URL was generated. 
	headers := map[string]string{
		"Content-Type": "text/plain;charset=utf8",
		"x-oss-storage-class": "Standard",
	}

	// Specify user metadata. Make sure that the user metadata here is the same as the user metadata specified when the presigned URL was generated. 
	metadata := map[string]string{
		"key1": "value1",
		"key2": "value2",
	}

	err := uploadFile(signedUrl, filePath, headers, metadata)
	if err != nil {
		fmt.Printf("An error occurred: %v\n", err)
	}
}

Python

import requests
from requests.auth import HTTPBasicAuth
import os

def upload_file(signed_url, file_path, headers=None, metadata=None):
    """
    Use a presigned URL to upload an object to OSS. 

    :param signed_url: the presigned URL. 
    :param file_path: the full path of the local file that you want to upload. 
    :param headers: request headers. This parameter is optional. 
    :param metadata: user metadata. This parameter is optional. 
    :return: None
    """
    if not headers:
        headers = {}
    if not metadata:
        metadata = {}

    # Add the x-oss-meta- prefix to the metadata key.
    for key, value in metadata.items():
        headers[f'x-oss-meta-{key}'] = value

    try:
        with open(file_path, 'rb') as file:
            response = requests.put(signed_url, data=file, headers=headers)
            print(f"Status code: {response.status_code}")
            if response.status_code == 200:
                print("The object is uploaded by using the library.")
            else:
                print("Upload failed.")
            print(response.text)
    except Exception as e:
        print(f"An error occurred: {e}")

if __name__ == "__main__":
    # Replace <signedUrl> with the generated signed URL. 
    signed_url = "<signedUrl>"
   
    # Specify the full path of the local file. By default, if you do not specify the full path of the local file, the local file is uploaded from the directory in which the script is stored. 
    file_path = "C:\\Users\\demo.txt"

    # Specify request headers. Make sure that the values of the request headers are the same as those specified when the presigned URL was generated. 
    headers = {
         "Content-Type": "text/plain;charset=utf8",
         "x-oss-storage-class": "Standard"
    }

    # Specify user metadata. Make sure that the user metadata is the same as the user metadata specified when the pesigned URL was generated. 
    metadata = {
         "key1": "value1",
         "key2": "value2"
    }

    upload_file(signed_url, file_path, headers, metadata)

Node.js

const fs = require('fs');
const axios = require('axios');

async function uploadFile(signedUrl, filePath, headers = {}, metadata = {}) {
    try {
        // Add the x-oss-meta- prefix to the metadata keys.
        for (const [key, value] of Object.entries(metadata)) {
            headers[`x-oss-meta-${key}`] = value;
        }

        // Create a readable stream.
        const fileStream = fs.createReadStream(filePath);

        // Send a PUT request.
        const response = await axios.put(signedUrl, fileStream, {
            headers: headers
        });

        console.log(`Status code: ${response.status}`);
        if (response.status === 200) {
            console.log("The object is uploaded by using the library.");
        } else {
            console.log("Upload failed.");
        }
        console.log(response.data);
    } catch (error) {
        console.error(`An error occurred: ${error.message}`);
    }
}

// Specify the main function.
(async () => {
    // Replace <signedUrl> with the presigned URL. 
    const signedUrl = "<signedUrl>";

    // Specify the full path of the local file that you want to upload. By default, if you do not specify the full path of the local file, the local file is uploaded from the directory in which the script is stored. 
    const filePath = "C:\\Users\\demo.txt";

    // Specify request headers. Make sure that the values of the request headers are the same as those specified when the presigned URL was generated. 
    const headers = {
         "Content-Type": "text/plain;charset=utf8",
         "x-oss-storage-class": "Standard"
    };

    // Specify user metadata. Make sure that the user metadata here is the same as the user metadata specified when the presigned URL was generated. 
    const metadata = {
         "key1": "value1",
         "key2": "value2"
    };

    await uploadFile(signedUrl, filePath, headers, metadata);
})();

Browser.js

Important

When you use Browser.js code to upload an object based on a presigned URL, you may encounter a 403 error that indicates a signature inconsistency. This error arises from a signature verification failure, which occurs because the browser automatically adds the Content-Type request header, an element that was not specified when the presigned URL was generated. To resolve the error, you must specify the Content-Type header when you generate a presigned URL that is expected to be used in Browser.js code to upload data to OSS.

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>File Upload Example</title>
</head>
<body>
    <h1>File Upload Example</h1>

    <input type="file" id="fileInput" />
    <button id="uploadButton">Upload File</button>

    <script>
        // Replace <signedUrl> with the actual presigned URL.
        const signedUrl = "<signedUrl>"; 

        document.getElementById('uploadButton').addEventListener('click', async () => {
            const fileInput = document.getElementById('fileInput');
            const file = fileInput.files[0];

            if (file) {
                try {
                    await upload(file, signedUrl);
                } catch (error) {
                    console.error('Error during upload:', error);
                    alert('Upload failed: ' + error.message);
                }
            } else {
                alert('Please select a file to upload.');
            }
        });

        const upload = async (file, presignedUrl) => {
            const headers = {
                "Content-Type": "text/plain;charset=utf8",
                'x-oss-storage-class': 'Standard',
                'x-oss-meta-key1': 'value1',
                'x-oss-meta-key2': 'value2'
            };

            const response = await fetch(presignedUrl, {
                method: 'PUT',
                headers: headers,
                body: file
            });

            if (!response.ok) {
                throw new Error(`Upload failed, status: ${response.status}`);
            }

            alert('File uploaded successfully');
            console.log('File uploaded successfully');
        };
    </script>
</body>
</html>

C#

using System.Net.Http.Headers;

// Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
var filePath = "C:\\Users\\demo.txt";
// Replace <signedUrl> with the presigned URL.
var presignedUrl = "<signedUrl>";

// Create an HTTP client and a local file stream.
using var httpClient = new HttpClient(); 
using var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
using var content = new StreamContent(fileStream);
            
// Create a PUT request.
var request = new HttpRequestMessage(HttpMethod.Put, presignedUrl);
request.Content = content;

// If you configure headers such as the user metadata and storage class when the presigned URL was generated, these headers must be sent to the server when the presigned URL is used to upload a file.
// Specify request headers. Make sure that the values of the request headers are the same as those specified when the presigned URL was generated.
request.Content.Headers.ContentType = new MediaTypeHeaderValue("text/plain") { CharSet = "utf8" };  // Specify the content type.      
// Specify user metadata. Make sure that the user metadata is the same as the user metadata specified when the pesigned URL was generated.
request.Content.Headers.Add("x-oss-meta-key1", "value1");
request.Content.Headers.Add("x-oss-meta-key2", "value2");
// Specify the storage class of the object.
request.Content.Headers.Add("x-oss-storage-class", "Standard");

// Output the request header.
Console.WriteLine("Request header:");
foreach (var header in request.Content.Headers)
{
    Console.WriteLine($"{header.Key}: {string.Join(", ", header.Value)}");
}

// Send a request.
var response = await httpClient.SendAsync(request);

// Process the response.
if (response.IsSuccessStatusCode)
{
    Console.WriteLine($"Uploaded! Status Code: {response.StatusCode}");
    Console.WriteLine("Response Header:");
    foreach (var header in response.Headers)
    {
        Console.WriteLine($"{header.Key}: {string.Join(", ", header.Value)}");
    }
}
else
{
    string responseContent = await response.Content.ReadAsStringAsync();
    Console.WriteLine($"Upload failed! Status Code: {response.StatusCode}");
    Console.WriteLine("Response Content: " + responseContent);
}

C++

#include <iostream>
#include <fstream>
#include <curl/curl.h>
#include <map>
#include <string>

// Specify the callback function that is used to process the HTTP response.
size_t WriteCallback(void* contents, size_t size, size_t nmemb, std::string* output) {
    size_t totalSize = size * nmemb;
    output->append((char*)contents, totalSize);
    return totalSize;
}

void uploadFile(const std::string& signedUrl, const std::string& filePath, const std::map<std::string, std::string>& headers, const std::map<std::string, std::string>& metadata) {
    CURL* curl;
    CURLcode res;
    std::string readBuffer;

    curl_global_init(CURL_GLOBAL_DEFAULT);
    curl = curl_easy_init();

    if (curl) {
        // Specify the presigned URL.
        curl_easy_setopt(curl, CURLOPT_URL, signedUrl.c_str());

        // Set the request method to PUT.
        curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);

        // Open the local file.
        FILE* file = fopen(filePath.c_str(), "rb");
        if (!file) {
            std::cerr << "Unable to open the file: " << filePath << std::endl;
            return;
        }

        // Specify the size of the local file.
        fseek(file, 0, SEEK_END);
        long fileSize = ftell(file);
        rewind(file);

        // Configure a file read callback.
        curl_easy_setopt(curl, CURLOPT_READDATA, file);
        curl_easy_setopt(curl, CURLOPT_INFILESIZE_LARGE, (curl_off_t)fileSize);

        // Specify request headers.
        struct curl_slist* chunk = nullptr;
        for (const auto& header : headers) {
            std::string headerStr = header.first + ": " + header.second;
            chunk = curl_slist_append(chunk, headerStr.c_str());
        }
        for (const auto& meta : metadata) {
            std::string metaStr = "x-oss-meta-" + meta.first + ": " + meta.second;
            chunk = curl_slist_append(chunk, metaStr.c_str());
        }
        curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);

        // Specify the callback function that is used to process the response.
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteCallback);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &readBuffer);

        // Execute the request.
        res = curl_easy_perform(curl);

        // Check the response.
        if (res != CURLE_OK) {
            std::cerr << "curl_easy_perform() failed: " << curl_easy_strerror(res) << std::endl;
        } else {
            long responseCode;
            curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &responseCode);
            std::cout << "Status code: " << responseCode << std::endl;
            if (responseCode == 200) {
                std::cout << "The object is uploaded by using the network library." << std::endl;
            } else {
                std::cout << "Upload failed." << std::endl;
            }
            std::cout << readBuffer << std::endl;
        }

        // Clear the cURL handle.
        fclose(file);
        curl_slist_free_all(chunk);
        curl_easy_cleanup(curl);
    }

    curl_global_cleanup();
}

int main() {
    // Replace <signedUrl> with the presigned URL. 
    std::string signedUrl = "<signedUrl>";

    // Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
    std::string filePath = "C:\\Users\\demo.txt";

    // Specify request headers. Make sure that the values of the request headers are the same as those specified when the presigned URL was generated. 
    std::map<std::string, std::string> headers = {
         {"Content-Type", "text/plain;charset=utf8"},
         {"x-oss-storage-class", "Standard"}
    };

    // Specify user metadata. Make sure that the user metadata here is the same as the user metadata specified when the presigned URL was generated. 
    std::map<std::string, std::string> metadata = {
         {"key1", "value1"},
         {"key2", "value2"}
    };

    uploadFile(signedUrl, filePath, headers, metadata);

    return 0;
}

Android

import android.os.AsyncTask;
import android.util.Log;

import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;

public class SignUrlUploadActivity extends AppCompatActivity {

    private static final String TAG = "SignUrlUploadActivity";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Replace <signedUrl> with the presigned URL. 
        String signedUrl = "<signedUrl>";

        // Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
        String pathName = "/storage/emulated/0/demo.txt";

        // Specify request headers. Make sure that the values of the request headers are the same as those specified when the presigned URL was generated. 
        Map<String, String> headers = new HashMap<>();
        headers.put("Content-Type", "text/plain;charset=utf8");
        headers.put("x-oss-storage-class", "Standard");

        // Specify user metadata. Make sure that the user metadata here is the same as the user metadata specified when the presigned URL was generated. 
        Map<String, String> userMetadata = new HashMap<>();
        userMetadata.put("key1", "value1");
        userMetadata.put("key2", "value2");

        new UploadTask().execute(signedUrl, pathName, headers, userMetadata);
    }

    private class UploadTask extends AsyncTask<Object, Void, Integer> {
        @Override
        protected Integer doInBackground(Object... params) {
            String signedUrl = (String) params[0];
            String pathName = (String) params[1];
            Map<String, String> headers = (Map<String, String>) params[2];
            Map<String, String> userMetadata = (Map<String, String>) params[3];

            try {
                URL url = new URL(signedUrl);
                HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                connection.setRequestMethod("PUT");
                connection.setDoOutput(true);
                connection.setUseCaches(false);

                // Specify request headers.
                for (Entry<String, String> header : headers.entrySet()) {
                    connection.setRequestProperty(header.getKey(), header.getValue());
                }

                // Specify user metadata.
                for (Entry<String, String> meta : userMetadata.entrySet()) {
                    connection.setRequestProperty("x-oss-meta-" + meta.getKey(), meta.getValue());
                }

                // Read the local file.
                File file = new File(pathName);
                FileInputStream fileInputStream = new FileInputStream(file);
                DataOutputStream dos = new DataOutputStream(connection.getOutputStream());

                byte[] buffer = new byte[1024];
                int count;
                while ((count = fileInputStream.read(buffer)) != -1) {
                    dos.write(buffer, 0, count);
                }

                fileInputStream.close();
                dos.flush();
                dos.close();

                // Obtain the response.
                int responseCode = connection.getResponseCode();
                Log.d(TAG, "Status code: " + responseCode);
                if (responseCode == 200) {
                    Log.d(TAG, "The object is uploaded by using the library.");
                } else {
                    Log.d(TAG, "Upload failed");
                }

                InputStream is = connection.getInputStream();
                byte[] responseBuffer = new byte[1024];
                StringBuilder responseStringBuilder = new StringBuilder();
                while ((count = is.read(responseBuffer)) != -1) {
                    responseStringBuilder.append(new String(responseBuffer, 0, count));
                }
                Log.d(TAG, responseStringBuilder.toString());

                return responseCode;
            } catch (IOException e) {
                e.printStackTrace();
                return -1;
            }
        }

        @Override
        protected void onPostExecute(Integer result) {
            super.onPostExecute(result);
            if (result == 200) {
                Toast.makeText(SignUrlUploadActivity.this, "Object uploaded", Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(SignUrlUploadActivity.this, "Upload failed", Toast.LENGTH_SHORT).show();
            }
        }
    }
}

Use presigned URLs for a multipart upload

To upload an object in parts by using presigned URLs, you must configure the part size and generate a presigned URL for each part. The following sample code uses presigned URLs for a multipart upload:

package main

import (
	"crypto/md5"
	"encoding/base64"
	"fmt"
	"log"
	"os"
	"strconv"
	"strings"

	"github.com/aliyun/aliyun-oss-go-sdk/oss"
)

func main() {
	// Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
	provider, err := oss.NewEnvironmentVariableCredentialsProvider()
	if err != nil {
		log.Printf("Error:%v", err)
	}
	// Create an OSSClient instance. 
	// Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.  
	client, err := oss.New("yourEndpoint", "", "", oss.SetCredentialsProvider(&provider))
	if err != nil {
		log.Printf("Error:%v", err)
	}
	bucketName := "bucket_name"

	bucket, err := client.Bucket(bucketName)
	if err != nil {
		log.Printf("Error:%v", err)
	}
	// Specify the full path of the object. Do not include the bucket name in the full path. 
	objectName := "example.txt"
	// Specify the full path of the local file that you want to upload. If the path of the local file is not specified, the local file is uploaded from the path of the project to which the sample program belongs. 
	localFile := "D:\\download\\demo.txt"

	// Split the local file into three parts. 
	chunks, err := oss.SplitFileByPartNum(localFile, 3)
	fd, err := os.Open(localFile)
	defer fd.Close()
	// Step 1: Initiate a multipart upload task and set the storage class of the object to Standard. 
	imur, err := bucket.InitiateMultipartUpload(objectName)
	// Step 2: Upload the parts. 
	var options []oss.Option

	for _, chunk := range chunks {
		// Configure MD5 verification. 
		buf := make([]byte, chunk.Size)
		fd.ReadAt(buf, chunk.Size)
		sum := md5.Sum(buf)
		b64 := base64.StdEncoding.EncodeToString(sum[:])
		options = []oss.Option{
			oss.ContentMD5(b64),
		}

		options = append(options, oss.AddParam("partNumber", strconv.Itoa(chunk.Number)))
		options = append(options, oss.AddParam("uploadId", imur.UploadID))
		// Generate a presigned URL. 
		signedURL, err := bucket.SignURL(objectName, oss.HTTPPut, 60, options...)
		if err != nil {
			log.Printf("Error:%v", err)
		}
		fmt.Printf("Presigned URL: %s\n", signedURL)
		err = bucket.PutObjectWithURL(signedURL, strings.NewReader(string(buf)), options...)
		if err != nil {
			log.Printf("Error:%v", err)
		}
	}

	lsRes, err := bucket.ListUploadedParts(imur)
	if err != nil {
		log.Printf("Error:%v", err)
	}

	// Traverse the parts and populate partETags. 
	var parts []oss.UploadPart
	for _, p := range lsRes.UploadedParts {
		parts = append(parts, oss.UploadPart{XMLName: p.XMLName, PartNumber: p.PartNumber, ETag: p.ETag})
	}

	// Step 3: Complete the multipart upload task. 
	_, err = bucket.CompleteMultipartUpload(imur, parts)
	if err != nil {
		log.Printf("Error:%v", err)
	}
	fmt.Println("Uploaded")
}

FAQ

When I use a presigned URL to upload a local file, will the file upload fail if the presigned URL expires during the upload?

No, the file upload will not fail, even if the presigned URL expires during the upload process.

A presigned URL can be used within its validity period, which is determined by the shorter duration of the token validity and the signature validity.

If I do not specify request headers and user metadata when I generate a URL, do I need to specify request headers and user metadata when I use the URL to upload a local file?

No, you do not need to specify request headers and user metadata.

The request headers and user metadata are optional parameters. If you do not specify request headers and user metadata, delete the relevant code in the preceding examples.

References

For the complete sample code that uploads files by using presigned URLs, visit GitHub.
For more information about the API operation that presigns a URL, see SignURL.