Object Storage Service:Initialize OSS SDK for Go

Prerequisites

Access credentials are configured. For more information, see Configure access credentials.

Create an OSSClient instance

package main

import (
	"log"

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

// Call handleError to handle unrecoverable errors and terminate the program after recording the error messages.
func handleError(err error) {
	log.Fatalf("Error: %v", err)
}

// Use setupClient to create and configure an OSSClient instance.
// Parameters:
//
//	endpoint: endpoint of the region in which the bucket is located.
//	region: the region in which the bucket is located.
//
// Return the created OSSClient instance.
func setupClient(endpoint, region string) (*oss.Client, error) {
	// Obtain access credentials from environment variables.
	provider, err := oss.NewEnvironmentVariableCredentialsProvider()
	if err != nil {
		return nil, err
	}

	// Create an OSSClient instance and use the signature algorithm V4.
	client, err := oss.New(endpoint, "", "", oss.SetCredentialsProvider(&provider), oss.AuthVersion(oss.AuthV4), oss.Region(region))
	if err != nil {
		return nil, err
	}

	return client, nil
}

func main() {
	// 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 your actual endpoint.
	endpoint := "yourEndpoint"

	// Specify the ID of the region that maps to the endpoint. Example: cn-hangzhou.
	region := "yourRegion"

	// Check whether the environment variables are configured.
	if endpoint == "" || region == "" {
		log.Fatal("Please set yourEndpoint and yourRegion.")
	}

	// Create and configure an OSSClient instance.
	client, err := setupClient(endpoint, region)
	if err != nil {
		handleError(err)
	}

	// Display the client information.
	log.Printf("Client: %#v\n", client)
}

package main

import (
	"log"

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

// Call handleError to handle unrecoverable errors and terminate the program after recording the error messages.
func handleError(err error) {
	log.Fatalf("Error: %v", err)
}

// Use setupClient to create and configure an OSSClient instance.
// Parameters:
//
//	endpoint: endpoint of the region in which the bucket is located.
//
// Return the created OSSClient instance.
func setupClient(endpoint string) (*oss.Client, error) {
	// Obtain access credentials from environment variables.
	provider, err := oss.NewEnvironmentVariableCredentialsProvider()
	if err != nil {
		return nil, err
	}

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

	return client, nil
}

func main() {
	// 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 your actual endpoint.
	endpoint := "yourEndpoint"

	// Check whether the environment variables are configured.
	if endpoint == "" {
		log.Fatal("Please set yourEndpoint.")
	}

	// Create and configure an OSSClient instance.
	client, err := setupClient(endpoint)
	if err != nil {
		handleError(err)
	}

	// Display the client information.
	log.Printf("Client: %#v\n", client)
}

package main

import (
	"log"

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

// Call handleError to handle unrecoverable errors and terminate the program after recording the error messages.
func handleError(err error) {
	log.Fatalf("Error: %v", err)
}

// Use setupClient to create and configure an OSSClient instance and use CNAME as an endpoint.
// Parameters:
//
//	endpoint: the custom domain name that you want to map to the bucket.
//
// Return the created OSSClient instance.
func setupClient(endpoint string) (*oss.Client, error) {
	// Obtain access credentials from environment variables.
	provider, err := oss.NewEnvironmentVariableCredentialsProvider()
	if err != nil {
		return nil, err
	}

	// Create an OSSClient instance and use CNAME as an endpoint.
	// Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou. Specify the actual region.
	clientOptions := []oss.ClientOption{oss.SetCredentialsProvider(&provider)}
	clientOptions = append(clientOptions, oss.Region("yourRegion"))
	clientOptions = append(clientOptions, oss.UseCname(true))
	// Specify the version of the signature algorithm.
	clientOptions = append(clientOptions, oss.AuthVersion(oss.AuthV4))
	client, err := oss.New(endpoint, "", "", clientOptions...)
	if err != nil {
		return nil, err
	}

	return client, nil
}

func main() {
	// Specify the endpoint of the region in which the bucket is located.
	// Example: custom-domain-for-your-bucket.com.
	endpoint := "yourEndpoint"

	// Check whether the environment variables are configured.
	if endpoint == "" {
		log.Fatal("Please set yourEndpoint.")
	}

	// Create and configure an OSSClient instance and use CNAME as an endpoint.
	client, err := setupClient(endpoint)
	if err != nil {
		handleError(err)
	}

	// Display the client information.
	log.Printf("Client: %#v\n", client)
}

Configure an OSSClient instance

You can use an OSSClient instance to configure parameters, such as the proxy server, connection timeout period, and the maximum number of connections. The following table describes the parameters.

Example:

package main

import (
	"log"

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

// Call handleError to handle unrecoverable errors and terminate the program after recording the error messages.
func handleError(err error) {
	log.Fatalf("Error: %v", err)
}

// Use setupClient to create and configure an OSSClient instance.
// Parameters:
//
//	endpoint: endpoint of the region in which the bucket is located.
//
// Return the created OSSClient instance.
func setupClient(endpoint string) (*oss.Client, error) {
	// Obtain access credentials from environment variables.
	provider, err := oss.NewEnvironmentVariableCredentialsProvider()
	if err != nil {
		return nil, err
	}

	// Set the number of connections to 10, the maximum number of idle connections of a server to 20, and the maximum number of connections of a server to 20.
	conn := oss.MaxConns(10, 20, 20)

	// Set the timeout period of an HTTP connection to 20 and the read or write timeout period of an HTTP connection to 60. Unit: seconds.
	time := oss.Timeout(20, 60)

	// Specify whether a custom domain name can be used as an endpoint. By default, a custom domain name cannot be used as an endpoint.
	cname := oss.UseCname(true)

	// Specify the User-Agent header. Default value: aliyun-sdk-go.
	userAgent := oss.UserAgent("aliyun-sdk-go")

	// Specify whether to enable HTTP redirection. Default value: true.
	redirect := oss.RedirectEnabled(true)

	// Specify whether to enable SSL-based authentication. Default value: false.
	verifySsl := oss.InsecureSkipVerify(false)

	// Specify whether to enable the IP address and port of the proxy server.
	// proxy := oss.Proxy("yourProxyHost")

	// Specify the IP address and the port of the proxy server, and the username and the password that are used to log on to the proxy server.
	authProxy := oss.AuthProxy("yourProxyHost", "yourProxyUserName", "yourProxyPassword")

	// Enable CRC-64.
	crc := oss.EnableCRC(true)

	// Specify the log mode.
	logLevel := oss.SetLogLevel(oss.LogOff)

	// Create an OSSClient instance. 
	// Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou. Specify the actual region.
	client, err := oss.New(endpoint, "", "", oss.SetCredentialsProvider(&provider), oss.Region("yourRegion"), oss.AuthVersion(oss.AuthV4),
		conn, time, cname, userAgent, authProxy, verifySsl, redirect, crc, logLevel)
	if err != nil {
		return nil, err
	}

	return client, nil
}

func main() {
	// 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 your actual endpoint. 
	endpoint := "yourEndpoint"

	// Check whether the environment variables are configured.
	if endpoint == "" {
		log.Fatal("Please set yourEndpoint.")
	}

	// Create and configure an OSSClient instance.
	client, err := setupClient(endpoint)
	if err != nil {
		handleError(err)
	}

	// Display the client information.
	log.Printf("Client: %#v\n", client)
}

Specify the request context

You can use the request context to manage the lifecycle of a request and pass context information related to the request.

The following sample code provides an example on how to specify the request context. You can specify the request context by using OSS SDK for Go 2.2.9 and later.

package main

import (
	"context"
	"fmt"
	"log"
	"time"

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

// Call handleError to handle unrecoverable errors and terminate the program after recording the error messages.
func handleError(err error) {
	log.Fatalf("Error: %v", err)
}

// Call uploadFile to upload a local file to an OSS bucket.
// Parameters:
//
//	bucketName: name of the bucket.
//	objectName: the full path of the object. Do not include the bucket name in the full path.
//	localFileName: the full path of the local file.
//	endpoint: endpoint of the region in which the bucket is located.
//
// If the local file is uploaded, a log is generated. Otherwise, an error message is returned.
func uploadFile(bucketName, objectName, localFileName, endpoint string) error {
	// Obtain access credentials from environment variables.
	provider, err := oss.NewEnvironmentVariableCredentialsProvider()
	if err != nil {
		return err
	}

	// Create an OSSClient instance. 
	// Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
	client, err := oss.New(endpoint, "", "", oss.SetCredentialsProvider(&provider), oss.Region("yourRegion"), oss.AuthVersion(oss.AuthV4))
	if err != nil {
		return err
	}

	// Create a bucket.
	bucket, err := client.Bucket(bucketName)
	if err != nil {
		return err
	}

	// Specify the request context.
	ctx := context.Background()

	// Specify the expiration time of the request context.
	ctx, cancel := context.WithTimeout(ctx, 5*time.Second)
	defer cancel()

	// Upload the local file to OSS.
	err = bucket.PutObjectFromFile(objectName, localFileName, oss.WithContext(ctx))
	if err != nil {
		select {
		case <-ctx.Done():
			return fmt.Errorf("Request cancelled or timed out")
		default:
			return err
		}
	}

	// After the local file is uploaded, a log is generated.
	log.Printf("File uploaded successfully: %s/%s", bucketName, objectName)
	return nil
}

func main() {
	// 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 your actual endpoint. 
	endpoint := "yourEndpoint"

	// Specify the name of the bucket. Example: examplebucket.
	bucketName := "examplebucket"

	// Specify the full path of the object. Do not include the bucket name in the full path.
	objectName := "yourObjectName"

	// Specify the full path of the local file.
	localFileName := "yourLocalFile"

	// Check whether the environment variables are configured.
	if endpoint == "" || bucketName == "" || objectName == "" || localFileName == "" {
		log.Fatal("Please set yourEndpoint, bucketName, objectName, and localFileName.")
	}

	// Upload the local file. If the local file fails to be uploaded, an error is reported. Resolve the error.
	if err := uploadFile(bucketName, objectName, localFileName, endpoint); err != nil {
		handleError(err)
	}

	// A message indicating that the object is uploaded is returned.
	log.Println("Upload Success!")
}

What to do next

After you initialize OSS SDK for Go, you can use the OSSClient instance to initiate a request. For more information, see Get started with OSS SDK for Go.