### Download Object Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/object.md

Basic example of downloading an object and reading its content. Ensure to close the response body.

```go
resp, err := client.Object.Get(context.Background(), "myfile.txt", nil)
if err != nil {
	panic(err)
}
deferr resp.Body.Close()

// Read response body
data, err := ioutil.ReadAll(resp.Body)
fmt.Println(string(data))
```

--------------------------------

### Complete COS Go SDK v5 Configuration Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/configuration.md

This example demonstrates a full configuration of the COS Go SDK, including setting the base URL, customizing the HTTP client with authorization transport, and configuring SDK options like retry mechanisms and CRC checks.

```go
package main

import (
	"context"
	"net/http"
	"net/url"
	"os"
	"time"

	"github.com/tencentyun/cos-go-sdk-v5"
)

func main() {
	// 1. Configure base URL
	u, _ := url.Parse("https://mybucket.cos.ap-beijing.myqcloud.com")
	baseURL := &cos.BaseURL{BucketURL: u}

	// 2. Configure HTTP client
	httpClient := &http.Client{
		Timeout: 100 * time.Second,
		Transport: &cos.AuthorizationTransport{
			SecretID:  os.Getenv("COS_SECRETID"),
			SecretKey: os.Getenv("COS_SECRETKEY"),
			Expire:    time.Hour,
		},
	}

	// 3. Create client
	client := cos.NewClient(baseURL, httpClient)

	// 4. Configure SDK options
	client.Conf = &cos.Config{
		EnableCRC:              true,
		RequestBodyClose:       false,
		RetryOpt: cos.RetryOptions{
			Count:          3,
			Interval:       100 * time.Millisecond,
			AutoSwitchHost: false,
		},
		ObjectKeySimplifyCheck: true,
	}

	// 5. Use client
	resp, err := client.Object.Get(context.Background(), "myfile.txt", nil)
	if err != nil {
		panic(err)
	}
	defer resp.Body.Close()
}
```

--------------------------------

### Test Suite Setup

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/vendor/github.com/stretchr/testify/README.md

Defines a test suite struct, including setup methods and test methods. The suite is run using `suite.Run`.

```go
// Basic imports
import (
    "testing"
    "github.com/stretchr/testify/assert"
    "github.com/stretchr/testify/suite"
)

// Define the suite, and absorb the built-in basic suite
// functionality from testify - including a T() method which
// returns the current testing context
type ExampleTestSuite struct {
    suite.Suite
    VariableThatShouldStartAtFive int
}

// Make sure that VariableThatShouldStartAtFive is set to five
// before each test
func (suite *ExampleTestSuite) SetupTest() {
    suite.VariableThatShouldStartAtFive = 5
}

// All methods that begin with "Test" are run as tests within a
// suite.
func (suite *ExampleTestSuite) TestExample() {
    assert.Equal(suite.T(), 5, suite.VariableThatShouldStartAtFive)
}

// In order for 'go test' to run this suite, we need to create
// a normal test function and pass our suite to suite.Run
func TestExampleTestSuite(t *testing.T) {
    suite.Run(t, new(ExampleTestSuite))
}
```

--------------------------------

### Install COS Go SDK

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/index.md

Installs the Tencent COS Go SDK v5 using the go get command.

```bash
go get -u github.com/tencentyun/cos-go-sdk-v5
```

--------------------------------

### Describe Job Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/batch.md

Example of how to retrieve and display details of a specific batch job using its jobID. It prints the job's ID, status, priority, and progress summary.

```go
result, _, err := client.Batch.DescribeJob(context.Background(), jobID)
if err != nil {
	panic(err)
}

job := result.Job
fmt.Printf("Job ID: %s\n", job.JobID)
fmt.Printf("Status: %s\n", job.JobStatus)
fmt.Printf("Priority: %d\n", job.Priority)
fmt.Printf("Progress: %d/%d succeeded, %d failed\n",
	job.ProgressSummary.NumberOfTasksSucceeded,
	job.ProgressSummary.TotalNumberOfTasks,
	job.ProgressSummary.NumberOfTasksFailed)
```

--------------------------------

### Minimal COS Client Setup

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Initialize a COS client with the minimal required configuration, including parsing the bucket URL.

```go
// Minimal setup
u, _ := url.Parse("https://bucket.cos.region.myqcloud.com")
c := cos.NewClient(&cos.BaseURL{BucketURL: u}, nil)
```

--------------------------------

### Download Object with Progress Tracking

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/object.md

Example of downloading an object while tracking download progress using a listener.

```go
opt := &cos.ObjectGetOptions{
	Listener: &cos.ProgressListener{
		ProgressChangedCallback: func(event *cos.ProgressEvent) {
			fmt.Printf("Downloaded: %d/%d bytes\n", event.ConsumedBytes, event.TotalBytes)
		},
	},
}

resp, err := client.Object.Get(context.Background(), "myfile.txt", opt)
```

--------------------------------

### Setup COS Client

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Demonstrates how to create a COS client instance. Ensure you have the necessary imports and provide your bucket URL and authentication credentials.

```go
import (
	"context"
	"net/http"
	"net/url"
	"os"
	"time"
	"github.com/tencentyun/cos-go-sdk-v5"
)

// Create client
u, _ := url.Parse("https://bucket-123456789.cos.ap-beijing.myqcloud.com")
client := cos.NewClient(&cos.BaseURL{BucketURL: u}, &http.Client{
	Timeout: 100 * time.Second,
	Transport: &cos.AuthorizationTransport{
		SecretID:  os.Getenv("COS_SECRETID"),
		SecretKey: os.Getenv("COS_SECRETKEY"),
	},
})
```

--------------------------------

### Example: Initiate Multipart Upload

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/object-multipart.md

Demonstrates how to initiate a multipart upload for a large file and retrieve the UploadID. Ensure you handle potential errors.

```go
result, _, err := client.Object.InitiateMultipartUpload(context.Background(), "largefile.bin", nil)
if err != nil {
	panic(err)
}

uploadID := result.UploadID
fmt.Printf("Initiated multipart upload. UploadID: %s\n", uploadID)
```

--------------------------------

### Image Processing Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/ci.md

Demonstrates how to initialize the CI client, define image processing rules, and execute the processing pipeline.

```APIDOC
## ImageProcess

### Description
Processes an image using a defined set of rules. This can include resizing, format conversion, and adding watermarks.

### Method
`client.CI.ImageProcess(context.Context, string, *cos.ImageProcessOptions) (*cos.ImageProcessResult, *Response, error)`

### Parameters
#### Path Parameters
- **objectKey** (string) - Required - The key of the object in the bucket to process.

#### Request Body
- **opt** (*cos.ImageProcessOptions) - Optional - Options for image processing, including `IsPicInfo` and `Rules`.
  - **IsPicInfo** (int) - Optional - Set to 1 to return image information.
  - **Rules** ([]cos.PicOperationsRules) - Optional - A list of processing rules to apply.
    - **FileId** (string) - Required - The ID of the output file.
    - **Rule** (string) - Required - The image processing rule string.

### Request Example
```go
opt := &cos.ImageProcessOptions{
	IsPicInfo: 1,
	Rules: []cos.PicOperationsRules{
		{
			FileId: "thumbnail.jpg",
			Rule: "imageMogr2/thumbnail/!100x100r/gravity/center/crop/100x100",
		},
		{
			FileId: "converted.png",
			Rule: "imageMogr2/format/png",
		},
	},
}
result, _, err := client.CI.ImageProcess(context.Background(), "original.jpg", opt)
```

### Response
#### Success Response (200)
- **OriginalInfo** (*PicOriginalInfo) - Original image metadata.
- **ProcessResults** ([]PicProcessObject) - Processed images.
- **ImgTargetRecResult** (*ImgTargetRecResult) - Target recognition results (optional).

#### Response Example
```json
{
  "OriginalInfo": {
    "ImageInfo": {
      "Width": 1920,
      "Height": 1080,
      "Format": "jpg",
      "Quality": 90,
      "Size": 102400,
      "ColorModel": "RGB"
    }
  },
  "ProcessResults": [
    {
      "Location": "thumbnail.jpg",
      "Width": 100,
      "Height": 100,
      "Format": "jpg",
      "Size": 5120
    },
    {
      "Location": "converted.png",
      "Width": 1920,
      "Height": 1080,
      "Format": "png",
      "Size": 204800
    }
  ]
}
```
```

--------------------------------

### Basic Assertion Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/vendor/github.com/stretchr/testify/README.md

Shows how to import and use the `assert` package for basic boolean assertions in a test function.

```go
package yours

import (
  "testing"
  "github.com/stretchr/testify/assert"
)

func TestSomething(t *testing.T) {

  assert.True(t, true, "True is true!")

}
```

--------------------------------

### Mock Object Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/vendor/github.com/stretchr/testify/README.md

Demonstrates how to use a mock object to set expectations on a method call and assert that those expectations were met.

```go
func TestSomething(t *testing.T) {

  // create an instance of our test object
  testObj := new(MyMockedObject)

  // setup expectations
  testObj.On("DoSomething", 123).Return(true, nil)

  // call the code we are testing
  targetFuncThatDoesSomethingWithObj(testObj)

  // assert that the expectations were met
  testObj.AssertExpectations(t)


}
```

```go
func TestSomethingElse(t *testing.T) {

  // create an instance of our test object
  testObj := new(MyMockedObject)

  // setup expectations with a placeholder in the argument list
  testObj.On("DoSomething", mock.Anything).Return(true, nil)

  // call the code we are testing
  targetFuncThatDoesSomethingWithObj(testObj)

  // assert that the expectations were met
  testObj.AssertExpectations(t)


}
```

--------------------------------

### Example of Encoding Picture Operations

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/ci.md

Demonstrates how to use the EncodePicOperations function with a sample PicOperations struct.

```go
pic := &cos.PicOperations{
	IsPicInfo: 1,
	Rules: []cos.PicOperationsRules{
		{
			FileId: "thumb.jpg",
			Rule: "imageMogr2/thumbnail/!50x50r/gravity/center/crop/50x50",
		},
	},
}

encoded := cos.EncodePicOperations(pic)
fmt.Println(encoded)
```

--------------------------------

### COS Client Setup with All Options

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Initialize a COS client with all available configuration options, including multiple URLs, custom HTTP client with timeout and session token, and SDK configurations like CRC and retry options.

```go
baseURL := &cos.BaseURL{
	BucketURL: bucketURL,
	ServiceURL: serviceURL,
	BatchURL: batchURL,
	CIURL: ciURL,
}

httpClient := &http.Client{
	Timeout: 100 * time.Second,
	Transport: &cos.AuthorizationTransport{
		SecretID: "xxx",
		SecretKey: "xxx",
		SessionToken: "xxx",
		Expire: time.Hour,
	},
}

c := cos.NewClient(baseURL, httpClient)
c.Conf.EnableCRC = true
c.Conf.RetryOpt.Count = 3
```

--------------------------------

### Download Object with Range

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/object.md

Example of downloading a specific byte range of an object. Useful for large files.

```go
opt := &cos.ObjectGetOptions{
	Range: "bytes=0-99",  // First 100 bytes
}

resp, err := client.Object.Get(context.Background(), "largefile.bin", opt)
```

--------------------------------

### Access Service APIs - Get Buckets

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/client.md

Demonstrates how to access the Service API to retrieve a list of buckets associated with the account.

```go
// Access service APIs
buckets, _, err := client.Service.Get(ctx)
```

--------------------------------

### Initialize COS Client and Get Object

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/README.md

Demonstrates how to initialize the COS client with your bucket, region, and credentials, and then retrieve an object from COS. Ensure your bucket name follows the format {name}-{appid} and set your SecretID and SecretKey, preferably via environment variables.

```go
package main

import (
	"context"
	"fmt"
	"io/ioutil"
	"net/http"
	"net/url"
	"os"
	"time"
	
	"github.com/tencentyun/cos-go-sdk-v5"
)

func main() {
	//将<bucket>和<region>修改为真实的信息
	//bucket的命名规则为{name}-{appid} ，此处填写的存储桶名称必须为此格式
	u, _ := url.Parse("https://<bucket>.cos.<region>.myqcloud.com")
	b := &cos.BaseURL{BucketURL: u}
	c := cos.NewClient(b, &http.Client{
		//设置超时时间
		Timeout: 100 * time.Second,
		Transport: &cos.AuthorizationTransport{
			//如实填写账号和密钥，也可以设置为环境变量
			SecretID:  os.Getenv("COS_SECRETID"),
			SecretKey: os.Getenv("COS_SECRETKEY"),
		},
	})

	name := "test/hello.txt"
	resp, err := c.Object.Get(context.Background(), name, nil)
	if err != nil {
		panic(err)
	}
	bs, _ := ioutil.ReadAll(resp.Body)
	resp.Body.Close()
	fmt.Printf("%s\n", string(bs))
}
```

--------------------------------

### Complete Batch Job Workflow Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/batch.md

Demonstrates the full lifecycle of a batch job: creation, setting status to Ready, and monitoring progress. Ensure you have initialized the COS client and provided necessary parameters like bucket names and target resources.

```go
package main

import (
	"context"
	"fmt"
	"time"

	"github.com/tencentyun/cos-go-sdk-v5"
)

func main() {
	// Assume baseURL and httpClient are initialized
	// baseURL := &cos.BaseURL{BucketURL: "https://my-bucket-1250000000.cos.ap-guangzhou.myqcloud.com"}
	// httpClient := &http.Client{}

	client := cos.NewClient(baseURL, httpClient)

	// Step 1: Create job
	createOpt := &cos.CreateJobOptions{
		Report: &cos.BatchJobReport{
			Bucket:  "report-bucket",
			Enabled: "true",
			Format:  "Report_CSV_20180820",
			Prefix:  "batch-reports/",
		},
		Operation: &cos.BatchJobOperation{
			PutObjectCopy: &cos.BatchJobOperationCopy{
				TargetResource:  "cos://target-bucket",
				TargetKeyPrefix: "archived/",
			},
		},
		Priority: 10,
	}

	result, _, err := client.Batch.CreateJob(context.Background(), createOpt)
	if err != nil {
		panic(err)
	}
	jobID := result.JobID
	fmt.Printf("Created job: %s\n", jobID)

	// Step 2: Update job status to Ready
	statusOpt := &cos.UpdateJobStatusOptions{
		RequestedJobStatus: "Ready",
	}
	_, err = client.Batch.UpdateJobStatus(context.Background(), jobID, statusOpt)
	if err != nil {
		panic(err)
	}
	fmt.Println("Job ready to run")

	// Step 3: Monitor job progress
	for i := 0; i < 10; i++ {
		describeResult, _, err := client.Batch.DescribeJob(context.Background(), jobID)
		if err != nil {
			panic(err)
		}

		job := describeResult.Job
		fmt.Printf("Status: %s\n", job.JobStatus)
		fmt.Printf("Progress: %d/%d tasks completed\n",
			job.ProgressSummary.NumberOfTasksSucceeded +
				job.ProgressSummary.NumberOfTasksFailed,
			job.ProgressSummary.TotalNumberOfTasks)

		if job.JobStatus == "Complete" || job.JobStatus == "Failed" {
			fmt.Printf("Job finished with status: %s\n", job.JobStatus)
			break
		}

		time.Sleep(5 * time.Second)
	}
}
```

--------------------------------

### Example: Uploading a Part File

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/object-multipart.md

Demonstrates how to open a file, upload it as a part of a multipart upload, and retrieve the ETag from the response. Ensure ContentLength is specified for readers other than standard types.

```go
partFile, err := os.Open("part1.bin")
if err != nil {
	panic(err)
}
defer partFile.Close()

resp, err := client.Object.UploadPart(
	context.Background(),
	"largefile.bin",
	uploadID,
	1,  // Part number
	partFile,
	nil,
)
if err != nil {
	panic(err)
}

etag := resp.Header.Get("ETag")
fmt.Printf("Part 1 uploaded. ETag: %s\n", etag)
```

--------------------------------

### Get Bucket Versioning Configuration

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Retrieves the versioning configuration for a bucket.

```go
// Get
result, _, _ := client.Bucket.GetVersioning(context.Background())
```

--------------------------------

### Service Access Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/client.md

Demonstrates how to access and utilize different service APIs provided by the client, such as listing buckets, managing objects, and initiating multipart uploads.

```APIDOC
## Service Access Example

### Description
This example shows how to interact with various service APIs available through the client, including operations on services, buckets, and objects.

### Example Usage

```go
// Access service APIs to list buckets
buckets, _, err := client.Service.Get(ctx)

// List objects in a bucket with specific options
listResp, _, err := client.Bucket.Get(ctx, &cos.BucketGetOptions{MaxKeys: 100})

// Download an object from the bucket
resp, err := client.Object.Get(ctx, "myfile.txt", nil)

// Initiate a multipart upload for a large file
uploadID, _, err := client.Object.InitiateMultipartUpload(ctx, "largefile.bin", nil)
```
```

--------------------------------

### Get Bucket Website Configuration

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/bucket.md

Retrieves the website configuration for a bucket. Use this to check current website settings.

```go
func (s *BucketService) GetWebsite(ctx context.Context, opt ...*BucketGetWebsiteOptions) (*BucketGetWebsiteResult, *Response, error)
```

--------------------------------

### Image Processing Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/ci.md

Demonstrates how to process an image using ImageProcessOptions, specifying resizing rules and output file name. It prints the location of the processed image.

```go
opt := &cos.ImageProcessOptions{
	IsPicInfo: 1,
	Rules: []cos.PicOperationsRules{
		{
			FileId: "resized.jpg",
			Rule: "imageMogr2/format/jpeg/w/200/h/200",
		},
	},
}

result, _, err := client.CI.ImageProcess(context.Background(), "photo.jpg", opt)
if err != nil {
	panic(err)
}

fmt.Printf("Output: %s\n", result.ProcessResults[0].Location)
```

--------------------------------

### Set Bucket Tagging

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Sets or replaces the tagging information for a bucket. This example adds a 'Type: Data' tag.

```go
// Set
client.Bucket.PutTagging(context.Background(), &cos.BucketPutTaggingOptions{
	TagSet: []cos.BucketTagSet{
		{Key: "Type", Value: "Data"},
	},
})
```

--------------------------------

### List all objects with pagination

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/bucket.md

This example demonstrates how to list all objects within a bucket, handling pagination to retrieve all items even if they exceed the initial response limit.

```APIDOC
## Get Bucket Objects

### Description
Lists objects in a bucket with pagination support.

### Method
GET

### Endpoint
/bucket

### Parameters
#### Query Parameters
- **MaxKeys** (int) - Optional - The maximum number of keys to return.
- **Marker** (string) - Optional - Specifies the object key to start listing from. Used for pagination.

### Request Example
```go
marker := ""
for {
	resp, _, err := client.Bucket.Get(context.Background(), &cos.BucketGetOptions{
		MaxKeys: 1000,
		Marker: marker,
	})
	if err != nil {
		panic(err)
	}

	for _, obj := range resp.Contents {
		fmt.Println(obj.Key)
	}

	if !resp.IsTruncated {
		break
	}
	marker = resp.NextMarker
}
```

### Response
#### Success Response (200)
- **Contents** ([]Object) - A list of objects in the bucket.
- **IsTruncated** (bool) - Indicates if the listing is truncated and more objects are available.
- **NextMarker** (string) - The marker to use for the next listing request if `IsTruncated` is true.
```

--------------------------------

### Create and Use COS Client Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/client.md

Demonstrates how to create a COS client with a custom HTTP client and authorization, then use it to retrieve an object. Ensure environment variables COS_SECRETID and COS_SECRETKEY are set.

```go
package main

import (
	"context"
	"net/http"
	"net/url"
	"os"
	"time"

	"github.com/tencentyun/cos-go-sdk-v5"
)

func main() {
	// Create bucket URL
	u, _ := url.Parse("https://mybucket.cos.ap-beijing.myqcloud.com")
	baseURL := &cos.BaseURL{BucketURL: u}

	// Create HTTP client with authorization
	httpClient := &http.Client{
		Timeout: 100 * time.Second,
		Transport: &cos.AuthorizationTransport{
			SecretID:  os.Getenv("COS_SECRETID"),
			SecretKey: os.Getenv("COS_SECRETKEY"),
		},
	}

	// Create COS client
	client := cos.NewClient(baseURL, httpClient)

	// Use the client
	resp, err := client.Object.Get(context.Background(), "myfile.txt", nil)
	if err != nil {
		panic(err)
	}
	defer resp.Body.Close()
}
```

--------------------------------

### Get Bucket Lifecycle Configuration

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Retrieves the lifecycle configuration for a bucket.

```go
// Get
result, _, _ := client.Bucket.GetLifecycle(context.Background())
```

--------------------------------

### Example Authorization Header

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/authentication.md

Illustrates the structure of the Authorization header automatically added by the SDK, including signing algorithm, access key, timestamps, and signature.

```text
Authorization: q-sign-algorithm=sha1&q-ak=AKIDz8krbsJ5GPXXXXXXXX&q-sign-time=1234567890;1234571490&q-key-time=1234567890;1234571490&q-header-list=host;x-cos-storage-class&q-url-param-list=prefix&q-signature=0123456789abcdef0123456789abcdef01234567
```

--------------------------------

### Customize Client Configuration

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/client.md

Example of how to customize the SDK client's configuration, including disabling CRC verification, adjusting retry attempts and intervals, and modifying object key validation.

```go
client := cos.NewClient(baseURL, httpClient)

// Customize configuration
client.Conf.EnableCRC = false              // Disable CRC verification
client.Conf.RetryOpt.Count = 5             // Increase retry attempts
client.Conf.RetryOpt.Interval = 100 * time.Millisecond
client.Conf.ObjectKeySimplifyCheck = false // Disable key validation
```

--------------------------------

### List All Buckets

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/service.md

Retrieves a list of all buckets associated with your account. This is the most basic usage of the Service Get API.

```go
resp, _, err := client.Service.Get(context.Background())
if err != nil {
	panic(err)
}

for _, bucket := range resp.Buckets {
	fmt.Printf("Bucket: %s (Region: %s, Created: %s)\n",
		bucket.Name, bucket.Location, bucket.CreationDate)
}
```

--------------------------------

### Configure COS Client Access Settings

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/configuration.md

Example of initializing a COS client and modifying its configuration for CRC verification and retry attempts.

```go
client := cos.NewClient(baseURL, httpClient)
client.Conf.EnableCRC = false          // Disable CRC verification
client.Conf.RetryOpt.Count = 5         // Set retry attempts
```

--------------------------------

### Mock Object Setup in Go with Testify

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/vendor/github.com/stretchr/testify/README.md

The mock package facilitates creating mock objects for dependency injection in tests. Define mock types and their methods to simulate behavior and record calls.

```go
package yours

import (
  "testing"
  "github.com/stretchr/testify/mock"
)

/*
  Test objects
*/

// MyMockedObject is a mocked object that implements an interface
// that describes an object that the code I am testing relies on.
type MyMockedObject struct{
  mock.Mock
}

// DoSomething is a method on MyMockedObject that implements some interface
// and just records the activity, and returns what the Mock object tells it to.
//
// In the real object, this method would do something useful, but since this
// is a mocked object - we're just going to stub it out.
//
// NOTE: This method is not being tested here, code that uses this object is.
func (m *MyMockedObject) DoSomething(number int) (bool, error) {

  args := m.Called(number)
  return args.Bool(0), args.Error(1)

}
```

--------------------------------

### Set bucket lifecycle policy

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/bucket.md

This example shows how to set a lifecycle policy for a bucket, defining rules for object expiration based on prefixes and days.

```APIDOC
## Put Bucket Lifecycle

### Description
Sets the lifecycle configuration for a bucket.

### Method
PUT

### Endpoint
/bucket?lifecycle

### Parameters
#### Request Body
- **Rules** ([]BucketLifecycleRule) - Required - A list of lifecycle rules.
  - **ID** (string) - Required - The unique identifier for the rule.
  - **Filter** (BucketLifecycleFilter) - Optional - Specifies the objects to which the rule applies.
    - **Prefix** (string) - Optional - Filters objects with the specified prefix.
  - **Expiration** (BucketLifecycleExpiration) - Optional - Defines the expiration action.
    - **Days** (int) - Optional - The number of days after creation when objects expire.
```

--------------------------------

### Set Bucket Lifecycle Configuration

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Sets the lifecycle configuration for a bucket. This example configures objects with the prefix 'logs/' to expire after 30 days.

```go
// Set (expire objects after 30 days)
client.Bucket.PutLifecycle(context.Background(), &cos.BucketPutLifecycleOptions{
	Rules: []cos.BucketLifecycleRule{
		{
			ID: "rule1",
			Filter: &cos.BucketLifecycleFilter{
				Prefix: "logs/",
			},
			Expiration: &cos.BucketLifecycleExpiration{
				Days: 30,
			},
		},
	},
})
```

--------------------------------

### Common COS Operations

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/START_HERE.md

Provides examples for common COS tasks including uploading, downloading to a file, listing objects, deleting objects, and generating presigned URLs. These snippets assume the client has already been initialized.

```go
// Upload
client.Object.Put(ctx, "key", file, nil)
```

```go
// Download
client.Object.GetToFile(ctx, "key", "/tmp/file", nil)
```

```go
// List objects
client.Bucket.Get(ctx, &cos.BucketGetOptions{MaxKeys: 100})
```

```go
// Delete
client.Object.Delete(ctx, "key")
```

```go
// Presigned URL
url, _ := client.Object.GetPresignedURL(ctx, "GET", "key", ak, sk, time.Hour, nil)
```

--------------------------------

### Get (Download Object) Function Signature

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/object.md

Signature for downloading an object from a bucket. Supports context, object name, options, and version ID.

```go
func (s *ObjectService) Get(ctx context.Context, name string, opt *ObjectGetOptions, id ...string) (*Response, error)
```

--------------------------------

### Setting Environment Variables for COS Credentials

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/configuration.md

This example shows how to set environment variables for COS credentials and region. These variables are commonly used to configure the SDK.

```bash
export COS_SECRETID=your_access_key_id
export COS_SECRETKEY=your_secret_access_key
export COS_REGION=ap-beijing
export COS_BUCKET=mybucket
```

--------------------------------

### COS Client Setup with Custom Timeout

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Configure a COS client with a custom HTTP client, including a specific timeout and an authorization transport.

```go
// With custom timeout
c := cos.NewClient(baseURL, &http.Client{
	Timeout: 30 * time.Second,
	Transport: &cos.AuthorizationTransport{
		SecretID:  "xxx",
		SecretKey: "xxx",
	},
})
```

--------------------------------

### Update Job Status Example

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/batch.md

Example of how to update the status of a batch job using the UpdateJobStatusOptions. Ensure you have a valid jobID.

```go
opt := &cos.UpdateJobStatusOptions{
	RequestedJobStatus: "Ready",
	StatusUpdateReason: "Starting bulk copy operation",
}

resp, err := client.Batch.UpdateJobStatus(context.Background(), jobID, opt)
if err != nil {
	panic(err)
}
fmt.Println("Job status updated")
```

--------------------------------

### Buckets: Tagging

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Get or set tags for a bucket.

```APIDOC
## Buckets: Tagging

### Description
Manages tags associated with a bucket, which can be used for organizing, managing costs, and controlling access.

### Methods
- GetTagging
- PutTagging

### Usage Example
```go
// Get
result, _, _ := client.Bucket.GetTagging(context.Background())

// Set
client.Bucket.PutTagging(context.Background(), &cos.BucketPutTaggingOptions{
	TagSet: []cos.BucketTagSet{
		{Key: "Type", Value: "Data"},
	},
})
```
```

--------------------------------

### Set Bucket Lifecycle Policy - Go

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/bucket.md

Configure a lifecycle rule for a bucket, such as expiring objects after a specified number of days. This example sets a rule to expire objects in the 'logs/' prefix after 90 days.

```go
lifecycle := &cos.BucketLifecycleRule{
	ID: "rule1",
	Filter: &cos.BucketLifecycleFilter{
		Prefix: "logs/",
	},
	Expiration: &cos.BucketLifecycleExpiration{
		Days: 90,
	},
}

opt := &cos.BucketPutLifecycleOptions{
	Rules: []cos.BucketLifecycleRule{*lifecycle},
}

_, err := client.Bucket.PutLifecycle(context.Background(), opt)
```

--------------------------------

### Initialize COS Client and Download Object

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/START_HERE.md

Demonstrates how to initialize the COS client with your bucket URL and credentials, and then download an object. Ensure your COS_SECRETID and COS_SECRETKEY environment variables are set.

```go
package main

import (
	"context"
	"fmt"
	"net/http"
	"net/url"
	"os"
	"time"

	"github.com/tencentyun/cos-go-sdk-v5"
)

func main() {
	// Initialize
	u, _ := url.Parse("https://bucket-123456789.cos.ap-beijing.myqcloud.com")
	client := cos.NewClient(&cos.BaseURL{BucketURL: u}, &http.Client{
		Timeout: 100 * time.Second,
		Transport: &cos.AuthorizationTransport{
			SecretID:  os.Getenv("COS_SECRETID"),
			SecretKey: os.Getenv("COS_SECRETKEY"),
		},
	})

	// Download
	resp, err := client.Object.Get(context.Background(), "file.txt", nil)
	if err != nil {
		panic(err)
	}
	defer resp.Body.Close()

	// Use response body...
}
```

--------------------------------

### Buckets: Versioning

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Get or enable/disable versioning for a bucket.

```APIDOC
## Buckets: Versioning

### Description
Manages the versioning state of a bucket, allowing you to keep multiple versions of an object to protect against accidental overwrites or deletions.

### Methods
- GetVersioning
- PutVersioning

### Usage Example
```go
// Get
result, _, _ := client.Bucket.GetVersioning(context.Background())

// Enable
client.Bucket.PutVersioning(context.Background(), &cos.BucketPutVersioningOptions{
	Status: "Enabled",
})
```
```

--------------------------------

### Buckets: Lifecycle

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Get or set the lifecycle configuration for a bucket.

```APIDOC
## Buckets: Lifecycle

### Description
Manages the lifecycle of objects within a bucket, defining rules for expiration or transition based on age or other criteria.

### Methods
- GetLifecycle
- PutLifecycle

### Usage Example
```go
// Get
result, _, _ := client.Bucket.GetLifecycle(context.Background())

// Set (expire objects after 30 days)
client.Bucket.PutLifecycle(context.Background(), &cos.BucketPutLifecycleOptions{
	Rules: []cos.BucketLifecycleRule{
		{
			ID: "rule1",
			Filter: &cos.BucketLifecycleFilter{
				Prefix: "logs/",
			},
			Expiration: &cos.BucketLifecycleExpiration{
				Days: 30,
			},
		},
	},
})
```
```

--------------------------------

### Get Bucket Tagging

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Retrieves the tagging information for a bucket.

```go
// Get
result, _, _ := client.Bucket.GetTagging(context.Background())
```

--------------------------------

### List Buckets with Pagination

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/service.md

Demonstrates how to list buckets with pagination using `MaxKeys` and `Marker`. If `resp.IsTruncated` is true, you can use `resp.NextMarker` to fetch the subsequent page.

```go
opt := &cos.ServiceGetOptions{
	MaxKeys: 100,
}

resp, _, err := client.Service.Get(context.Background(), opt)
if err != nil {
	panic(err)
}

for _, bucket := range resp.Buckets {
	fmt.Println(bucket.Name)
}

// Get next page
if resp.IsTruncated {
	opt.Marker = resp.NextMarker
	nextResp, _, _ := client.Service.Get(context.Background(), opt)
	// Process nextResp.Buckets
}
```

--------------------------------

### Buckets: ACL

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Get or set the Access Control List (ACL) for a bucket.

```APIDOC
## Buckets: ACL

### Description
Manages the Access Control List (ACL) for a bucket, allowing you to define permissions for different users or groups.

### Methods
- GetACL
- PutACL

### Usage Example
```go
// Get
result, _, _ := client.Bucket.GetACL(context.Background())

// Set
client.Bucket.PutACL(context.Background(), &cos.BucketPutACLOptions{
	Header: &cos.ACLHeaderOptions{
		XCosACL: "private",
	},
})
```
```

--------------------------------

### Get Bucket ACL

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Retrieves the Access Control List (ACL) for a bucket.

```go
// Get
result, _, _ := client.Bucket.GetACL(context.Background())
```

--------------------------------

### Buckets: CORS

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Get or set the Cross-Origin Resource Sharing (CORS) configuration for a bucket.

```APIDOC
## Buckets: CORS

### Description
Configures Cross-Origin Resource Sharing (CORS) for a bucket, enabling web applications from different domains to access resources in the bucket.

### Methods
- GetCORS
- PutCORS

### Usage Example
```go
// Get
result, _, _ := client.Bucket.GetCORS(context.Background())

// Set
client.Bucket.PutCORS(context.Background(), &cos.BucketPutCORSOptions{
	Rules: []cos.BucketCORSRule{
		{
			AllowedOrigins: []string{"https://example.com"},
			AllowedMethods: []string{"GET", "PUT"},
			MaxAgeSeconds: 3600,
		},
	},
})
```
```

--------------------------------

### Create, Update, and Describe Batch Jobs

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Shows how to create a batch job with a PutObjectCopy operation, update its status to 'Ready', and describe its progress.

```go
// Create job
result, _, _ := client.Batch.CreateJob(context.Background(), &cos.CreateJobOptions{
	Operation: &cos.BatchJobOperation{
		PutObjectCopy: &cos.BatchJobOperationCopy{
			TargetResource: "cos://target-bucket",
		},
	})

// Update status
client.Batch.UpdateJobStatus(context.Background(), result.JobID, 
	&cos.UpdateJobStatusOptions{
		RequestedJobStatus: "Ready",
	})

// Check progress
job, _, _ := client.Batch.DescribeJob(context.Background(), result.JobID)
fmt.Printf("Progress: %d/%d\n", job.ProgressSummary.NumberOfTasksSucceeded, 
	job.ProgressSummary.TotalNumberOfTasks)
```

--------------------------------

### Get Bucket CORS Configuration

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Retrieves the Cross-Origin Resource Sharing (CORS) configuration for a bucket.

```go
// Get
result, _, _ := client.Bucket.GetCORS(context.Background())
```

--------------------------------

### Get Service

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/README.md

Retrieves the service information for the COS account. This operation lists all buckets associated with the account.

```APIDOC
## Get Service

### Description
Retrieves the service information for the COS account. This operation lists all buckets associated with the account.

### Method
GET

### Endpoint
/

### Parameters
None

### Request Example
None

### Response
#### Success Response (200)
- **Buckets** (Array of Bucket) - A list of buckets owned by the requester.

#### Response Example
```json
{
  "Buckets": [
    {
      "Name": "examplebucket-1250000000",
      "CreationDate": "2023-01-01T12:00:00.000Z"
    }
  ]
}
```
```

--------------------------------

### Set Bucket ACL

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Sets the Access Control List (ACL) for a bucket. Example sets the bucket to private.

```go
// Set
client.Bucket.PutACL(context.Background(), &cos.BucketPutACLOptions{
	Header: &cos.ACLHeaderOptions{
		XCosACL: "private",
	},
})
```

--------------------------------

### Filter Buckets by Tag

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/service.md

Filters buckets based on specified tag key-value pairs, for example, 'Environment: Production'.

```go
opt := &cos.ServiceGetOptions{
	TagKey: "Environment",
	TagValue: "Production",
}

resp, _, err := client.Service.Get(context.Background(), opt)
if err != nil {
	panic(err)
}
```

--------------------------------

### Get Bucket Encryption Configuration

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/bucket.md

Retrieves the encryption configuration for a bucket. This is useful for verifying current encryption settings.

```go
func (s *BucketService) GetEncryption(ctx context.Context, opt ...*BucketGetEncryptionOptions) (*BucketGetEncryptionResult, *Response, error)
```

--------------------------------

### Access Object API - Download Object

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/client.md

Illustrates how to use the Object API to download a file from a bucket.

```go
// Download object
resp, err := client.Object.Get(ctx, "myfile.txt", nil)
```

--------------------------------

### Initialize COS Client

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/index.md

Initializes the COS client with bucket URL and credentials. Ensure your COS_SECRETID and COS_SECRETKEY environment variables are set.

```go
package main

import (
	"context"
	"net/http"
	"net/url"
	"os"
	"time"
	
	"github.com/tencentyun/cos-go-sdk-v5"
)

func main() {
	// Initialize client with bucket URL and credentials
	u, _ := url.Parse("https://bucket-name.cos.region.myqcloud.com")
	b := &cos.BaseURL{BucketURL: u}
	c := cos.NewClient(b, &http.Client{
		Timeout: 100 * time.Second,
		Transport: &cos.AuthorizationTransport{
			SecretID:  os.Getenv("COS_SECRETID"),
			SecretKey: os.Getenv("COS_SECRETKEY"),
		},
	})

	// Use the client to perform operations
	resp, err := c.Object.Get(context.Background(), "test/hello.txt", nil)
	if err != nil {
		panic(err)
	}
	defer resp.Body.Close()
}
```

--------------------------------

### Configure SDK Features and Retries

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Demonstrates how to enable/disable features like CRC verification and connection reuse, and configure retry options including count, interval, and auto-switch host.

```go
// Enable/disable features
client.Conf.EnableCRC = true              // Verify downloads
client.Conf.RequestBodyClose = false      // Reuse connections
client.Conf.ObjectKeySimplifyCheck = true // Validate keys

// Configure retries
client.Conf.RetryOpt.Count = 3
client.Conf.RetryOpt.Interval = 100 * time.Millisecond
client.Conf.RetryOpt.AutoSwitchHost = true
```

--------------------------------

### Get (List Objects)

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/api-reference/bucket.md

Lists objects within a specified bucket. This operation allows for filtering and pagination of the object list.

```APIDOC
## Get (List Objects)

### Description
Lists objects in a bucket. This operation supports filtering by prefix, delimiter, and marker, as well as controlling the number of returned items.

### Method
GET

### Endpoint
`/{bucketName}`

### Parameters
#### Query Parameters
- **prefix** (string) - Optional - Filters the objects to be returned, returning only those whose keys begin with the specified prefix.
- **delimiter** (string) - Optional - A delimiter is a character you can use to group objects by name. It acts like a folder separator.
- **encoding-type** (string) - Optional - Specifies the encoding method for the object keys.
- **marker** (string) - Optional - Specifies the object key to start the listing from. Objects with keys alphabetically preceding the marker will not be included.
- **max-keys** (int) - Optional - Sets the maximum number of objects to be returned in the response.

### Request Example
```go
opt := &cos.BucketGetOptions{
	MaxKeys: 100,
	Prefix: "logs/",
}

resp, _, err := client.Bucket.Get(context.Background(), opt)
if err != nil {
	panic(err)
}

for _, obj := range resp.Contents {
	fmt.Printf("Key: %s, Size: %d bytes\n", obj.Key, obj.Size)
}
```

### Response
#### Success Response (200)
- **Name** (string) - The name of the bucket.
- **Prefix** (string) - The prefix used for the listing.
- **Marker** (string) - The marker used for the listing.
- **NextMarker** (string) - The marker to be used for the next listing request if the results are truncated.
- **Delimiter** (string) - The delimiter used for the listing.
- **MaxKeys** (int) - The maximum number of keys returned in the response.
- **IsTruncated** (bool) - Indicates whether the list of objects is truncated.
- **Contents** ([]Object) - A list of objects in the bucket.
- **CommonPrefixes** ([]string) - A list of common prefixes, used when a delimiter is specified.
- **EncodingType** (string) - The encoding type used for the object keys.

#### Response Example
{
  "Name": "my-bucket",
  "Prefix": "logs/",
  "Marker": "",
  "NextMarker": "log_2023-01-01.txt",
  "Delimiter": "/",
  "MaxKeys": 100,
  "IsTruncated": true,
  "Contents": [
    {
      "Key": "logs/access.log",
      "LastModified": "2023-10-26T10:00:00Z",
      "ETag": "\"abcdef1234567890\"",
      "Size": 1024,
      "Owner": {
        "ID": "1234567890"
      },
      "StorageClass": "STANDARD"
    }
  ],
  "CommonPrefixes": [
    "logs/archive/"
  ],
  "EncodingType": "url"
}
```

--------------------------------

### Configuration Options

Source: https://github.com/tencentyun/cos-go-sdk-v5/blob/master/_autodocs/QUICK_REFERENCE.md

Shows how to configure various aspects of the SDK client, including feature flags, connection reuse, key validation, and retry mechanisms.

```APIDOC
## Configuration

This section covers various client configuration options.

### Feature Flags
- `client.Conf.EnableCRC` (bool): Enable/disable CRC checksum verification for downloads. Defaults to `false`.
- `client.Conf.RequestBodyClose` (bool): Controls whether to reuse connections after the request body is sent. Defaults to `true`.
- `client.Conf.ObjectKeySimplifyCheck` (bool): Enable/disable validation of object keys. Defaults to `false`.

### Retry Options
- `client.Conf.RetryOpt.Count` (int): The number of retry attempts. Defaults to `0`.
- `client.Conf.RetryOpt.Interval` (time.Duration): The interval between retry attempts. Defaults to `0`.
- `client.Conf.RetryOpt.AutoSwitchHost` (bool): Whether to automatically switch hosts on retry. Defaults to `false`.

### Credentials Update
To update credentials, access the underlying transport and use `SetCredential`.

#### Method Signature
```go
transport := client.client.Transport.(*cos.AuthorizationTransport)
transport.SetCredential(accessKey, secretKey, sessionToken)
```

### Example Configuration
```go
// Enable/disable features
client.Conf.EnableCRC = true              // Verify downloads
client.Conf.RequestBodyClose = false      // Reuse connections
client.Conf.ObjectKeySimplifyCheck = true // Validate keys

// Configure retries
client.Conf.RetryOpt.Count = 3
client.Conf.RetryOpt.Interval = 100 * time.Millisecond
client.Conf.RetryOpt.AutoSwitchHost = true

// Update credentials
transport := client.client.Transport.(*cos.AuthorizationTransport)
transport.SetCredential("new_ak", "new_sk", "")
```
```