tencent cloud

Download and Installation

Relevant resources

• Download COS XML C++ SDK source code below:
  Linux/Windows/macOS: XML Linux C++ SDK
• Download XML C++ SDK.
• Download the demo here
• For the SDK changelog, see Changelog.

Note：

If you encounter errors such as non-existent functions or methods when using the XML version of the SDK, please update the SDK to the latest version and try again.

Pre-Compiled (Recommended)

Download the XML C++ SDK source code. In the libs directory, you can find the ready-to-use pre-compiled libraries. Please choose one that suits your system version.

libs/linux/libcossdk.a # Linux static library. `libcossdk.a` is compiled based on GCC v4.8.5. If your compilation environment uses a different GCC version, you need to compile `libcossdk.a` again.
libs/linux/libcossdk-shared.so # Linux dynamic library
libs/Win32/cossdk.lib # Win32 library
libs/x64/cossdk.lib # Win64 library
libs/macOS/libcossdk.a # macOS static library
libs/macOS/libcossdk-shared.dylib # macOS dynamic library

Note：

Copy the libraries and the SDK include files that suit your OS to your project.

The following third-party dependent libraries can be found in the Third-party directory:

third_party/lib/linux/poco/ # Linux-dependent POCO dynamic library. The POCO library is compiled based on OpenSSL v1.0.2. If your compilation environment uses a different OpenSSL version, you need to compile the POCO library again.
third_party/lib/Win32/openssl/ # Win32-dependent OpenSSL library
third_party/lib/Win32/poco/ # Win32-dependent POCO library
third_party/lib/x64/openssl/ # Win64-dependent OpenSSL library
third_party/lib/x64/poco/ # Win64-dependent POCO library
third_party/lib/macOS/poco/ # macOS-dependent POCO library

Note：

Copy the dependent libraries that suit your OS to your project.

Manual Compilation

Compilation options

You can configure the following compilation options using the CMakeLists.txt file in the root directory:

option(BUILD_UNITTEST "Build unittest" OFF) # Configure unit testing compilation.
option(BUILD_DEMO "Build demo" ON) # Configure demo testable code compilation.
option(BUILD_SHARED_LIB "Build shared library" OFF) # Configure dynamic library compilation.

Dependent libraries

Shared libraries: POCO, OpenSSL, Crypto

Compiling Linux SDK

1. Install the compiler and dependent libraries.

   yum install -y gcc gcc-c++ make cmake openssl
   # The CMake version should be later than 2.8.
   

2. Compile the SDK.
   Download the XML C++ SDK source code to your development environment and run the following command:

   cd ${cos-cpp-sdk} 
   mkdir -p build 
   cd build 
   cmake .. 
   make
   

3. Install the POCO libraries.

   cd ${cos-cpp-sdk} 
   sh install-libpoco.sh
   

Note：

This script installs the POCO dynamic library to the /usr/lib64 directory and creates a soft link. To use a COS SDK in the production environment, install the POCO library to the production environment as well.

4. Run the demo.

   Note：

   You can skip this step if you don’t need to test the demo.

   cd ${cos-cpp-sdk} 
   vim demo/cos_demo.cpp  # Modify the bucket name and testable code in the demo.
   vim CMakeLists.txt # Set "BUILD_DEMO" to "ON" in "CMakeLists.txt" in the root directory to start compiling the demo.
   cd build && make # Compile the demo.
   ls bin/cos_demo # The generated executable file is in the "bin" directory.
   vim bin/config.json # Modify the key and the region.
   cd bin && ./cos_demo # Run the demo.
   

5. Use the SDK.
   The compiled libraries can be found in the build/lib directory. The static library name is libcossdk.a and the dynamic library name is libcossdk-shared.so. During actual use, copy the libraries to your project and copy the include directory to the include directory of your project.

Compiling Windows SDK

1. Install Visual Studio 2017.
   Install the Visual Studio 2017 development environment.

2. Install CMake.
   Download the Windows version of the CMake compiler from the CMake official website, and configure ${CMake installation path}\bin in the Path environment variable.

3. Compile the SDK.
   i. Download XML Windows C++ SDK source code to your development environment.
   ii. Open the Windows command-line tool, cd to the directory of the C++ SDK source code, and run the following command:

   mkdir build
   cd build
   cmake .. # Generate the Win32 Makefile.
   cmake -G "Visual Studio 15 Win64" .. # Generate the Win64 Makefile.
   

   iii. Use Visual Studio 2017 to open the Solution Explorer and perform compilation.

4. Test the demo.
   

   Note：

   You can skip this step if you don’t need to test the demo.

   Modify the demo code and compile it. The generated cos_demo.exe file is in the bin directory. You can modify bin/config.json to run cos_demo.exe.

5. Use the SDK.
   The compiled libraries can be found in the build/Release directory. The static library is named cossdk.lib. During actual use, copy the library to your project and copy the include directory to the include directory of your project.

Compiling Mac SDK

1. Install the compiler and dependent libraries.

   brew install gcc make cmake openssl
   

2. Compile the SDK.
   Download the XML C++ SDK source code to your development environment and run the following command:

   cd ${cos-cpp-sdk} 
   mkdir -p build 
   cd build 
   cmake .. 
   make
   

3. Install the POCO libraries.
   The POCO libraries are in the third_party/lib/macOS/poco directory. You can install them by yourself.

4. Run the demo.

   Note：

   You can skip this step if you don’t need to test the demo.

   Modify the demo code and compile it. The generated cos_demo is in the bin directory. Copy cos-cpp-sdk-v5/demo/config.json to the bin directory and modify bin/config.json. Then you can run cos_demo.

5. Use the SDK.
   The compiled libraries can be found in the build/lib directory. The static library is named libcossdk.a, and the dynamic library is named libcossdk-shared.dylib. During actual use, copy the libraries to your project and copy the include directory to the include directory of your project.

Note：

If you encounter compilation problems, please refer to C++ SDK FAQ.

Getting Started

The section below describes how to use the COS C++ SDK to perform basic operations, such as initializing a client, creating a bucket, querying a bucket list, uploading an object, querying an object list, downloading an object, and deleting an object.

Note：

For the definition of terms such as SecretId, SecretKey, and Bucket, see COS Glossary.

Initialization

Note：

• We recommend you use a sub-account key and environment variables to call the SDK for security purposes. When authorizing a sub-account, follow the Notes on Principle of Least Privilege to avoid leaking resources besides your buckets and objects.
• If you must use a permanent key, we recommend you follow the Notes on Principle of Least Privilege to limit the scope of permission on the permanent key.

Accessing COS using a temporary key

To access COS using a temporary key, see the code below:

#include "cos_api.h"
#include "cos_sys_config.h"
#include "cos_defines.h"
int main(int argc, char *argv[]) {
    // Using the configuration file for initialization is not recommended because secret_id and secret_key of a temporary key will change.
    qcloud_cos::CosConfig config(appid, "secret_id", "secret_key", "region");
    // secret_id and secret_key of a temporary key are required. For details on how to generate and use a temporary key, visit https://www.tencentcloud.com/document/product/436/14048.
    config.SetTmpToken("xxx");
    qcloud_cos::CosAPI cos(config);
}

Accessing COS using a permanent key (not recommended)

To access COS using a permanent key, see the code below:

#include "cos_api.h"
#include "cos_sys_config.h"
#include "cos_defines.h"
int main(int argc, char *argv[]) {
    qcloud_cos::CosConfig config("./config.json");  // Use the configuration file for initialization
    // Or use constructor parameters for initialization directly
    //qcloud_cos::CosConfig config(appid, "secret_id", "secret_key", "region");  // Permanent key
    qcloud_cos::CosAPI cos(config);
}

Fields in the configuration file are described as follows:

{
"SecretId":"********************************", // Replace `sercret_id` with your `SecretId`. We recommend you use a sub-account key and follow the principle of least privilege to reduce risks. For information about how to obtain a sub-account key, visit https://www.tencentcloud.com/document/product/598/37140?from_cn_redirect=1.
"SecretKey":"*******************************", // Replace `sercret_key` with your `SecretKey`. We recommend you use a sub-account key and follow the principle of least privilege to reduce risks. For information about how to obtain a sub-account key, visit https://www.tencentcloud.com/document/product/598/37140?from_cn_redirect=1.
"Region":"ap-guangzhou",                // Bucket region. Replace it with your bucket region, which can be viewed on the overview page in the COS console at https://console.tencentcloud.com/cos5/bucket/. For more information about regions, visit https://www.tencentcloud.com/document/product/436/6224?from_cn_redirect=1.
"SignExpiredTime":360,              // Signature expiration time, in seconds
"ConnectTimeoutInms":6000,          // Connection timeout, in milliseconds
"ReceiveTimeoutInms":60000,         // Receive timeout, in milliseconds
"UploadPartSize":10485760,          // Size of the part to upload, which can be 1 MB to 5 GB. Defaults to 10 MB.
"UploadCopyPartSize":20971520,      // Size of the copied part for upload, which can be 5 MB to 5 GB. Defaults to 20 MB.
"UploadThreadPoolSize":5,           // Size of the upload thread pool for a single multipart upload
"DownloadSliceSize":4194304,        // Size of a part to download
"DownloadThreadPoolSize":5,         // Size of the download thread pool for a single file
"AsynThreadPoolSize":2,             // Async thread pool size for uploads/downloads
"LogoutType":1,                     // Log output type. Valid values: 0 (no output), 1 (output to screen), 2 (output to syslog)
"LogLevel":3,                       // Log level. Valid values: 1 (ERR), 2 (WARN), 3 (INFO), 4 (DBG)
"IsDomainSameToHost":false,         // Whether there is a dedicated host
"DestDomain":"",                    // Dedicated host
"IsUseIntranet":false,              // Whether a specific IP and port number are used
"IntranetAddr":""                   // IP and port number, such as "127.0.0.1:80"
}

Printing SDK internal logs to a custom log file

To print SDK internal logs (especially for Windows OS) to a custom log file, see the code below:

#include "cos_api.h"
#include "cos_sys_config.h"
#include "cos_defines.h"
void TestLogCallback(const std::string& log) {
    std::ofstream ofs;
    ofs.open("test.log", std::ios_base::app);
    ofs << log;
    ofs.close();
}
int main(int argc, char** argv) {
    qcloud_cos::CosConfig config("./config.json");
    config.SetLogCallback(&TestLogCallback);
    qcloud_cos::CosAPI cos(config);
}

Creating a bucket

#include "cos_api.h"
#include "cos_sys_config.h"
#include "cos_defines.h"

int main(int argc, char *argv[]) {
    // 1. Specify the path to the configuration file and initialize CosConfig
    qcloud_cos::CosConfig config("./config.json");
    qcloud_cos::CosAPI cos(config);
    
    // 2. Construct the PUT Bucket request
    std::string bucket_name = "examplebucket-1250000000"; // Replace it with your bucket name, which is in the format of BucketName-APPID (APPID is required). It can be viewed in the COS console at https://console.tencentcloud.com/cos5/bucket.
    qcloud_cos::PutBucketReq req(bucket_name);
    qcloud_cos::PutBucketResp resp;
    
    // 3. Call the PUT Bucket API
    qcloud_cos::CosResult result = cos.PutBucket(req, &resp);
    
    // 4. Process the call result
    if (result.IsSucc()) {
        // Group created successfully
    } else {
        // Failed to create the bucket. You can call the CosResult member functions to output the error information such as the requestID.
        std::cout << "HttpStatus=" << result.GetHttpStatus() << std::endl;
        std::cout << "ErrorCode=" << result.GetErrorCode() << std::endl;
        std::cout << "ErrorMsg=" << result.GetErrorMsg() << std::endl;
        std::cout << "ResourceAddr=" << result.GetResourceAddr() << std::endl;
        std::cout << "XCosRequestId=" << result.GetXCosRequestId() << std::endl;
        std::cout << "XCosTraceId=" << result.GetXCosTraceId() << std::endl;
    }
}

Querying the bucket list

#include "cos_api.h"
#include "cos_sys_config.h"
#include "cos_defines.h"

int main(int argc, char *argv[]) {
    // 1. Specify the path to the configuration file and initialize CosConfig
    qcloud_cos::CosConfig config("./config.json");
    qcloud_cos::CosAPI cos(config);
    
    // 2. Construct a request to query the bucket list
    qcloud_cos::GetServiceReq req;
    qcloud_cos::GetServiceResp resp;
    qcloud_cos::CosResult result = cos.GetService(req, &resp);
    
    // 3. Get the response information
    const qcloud_cos::Owner& owner = resp.GetOwner();
    const std::vector<qcloud_cos::Bucket>& buckets = resp.GetBuckets();
    std::cout << "owner.m_id=" << owner.m_id << ", owner.display_name=" << owner.m_display_name << std::endl;
    
    for (std::vector<qcloud_cos::Bucket>::const_iterator itr = buckets.begin(); itr != buckets.end(); ++itr) {
        const qcloud_cos::Bucket& bucket = *itr;
        std::cout << "Bucket name=" << bucket.m_name << ", location="
            << bucket.m_location << ", create_date=" << bucket.m_create_date << std::endl;
    }
    
    // 4. Process the call result
    if (result.IsSucc()) {
        // Queried the bucket list successfully
    } else {
        // Failed to query the bucket list. You can call the CosResult member functions to output the error information such as requestID.
        std::cout << "HttpStatus=" << result.GetHttpStatus() << std::endl;
        std::cout << "ErrorCode=" << result.GetErrorCode() << std::endl;
        std::cout << "ErrorMsg=" << result.GetErrorMsg() << std::endl;
        std::cout << "ResourceAddr=" << result.GetResourceAddr() << std::endl;
        std::cout << "XCosRequestId=" << result.GetXCosRequestId() << std::endl;
        std::cout << "XCosTraceId=" << result.GetXCosTraceId() << std::endl;
    }
}

Uploading an object

#include "cos_api.h"
#include "cos_sys_config.h"
#include "cos_defines.h"

int main(int argc, char *argv[]) {
    // 1. Specify the path to the configuration file and initialize CosConfig
    qcloud_cos::CosConfig config("./config.json");
    qcloud_cos::CosAPI cos(config);
    
    // 2. Construct a request to upload a file
    std::string bucket_name = "examplebucket-1250000000"; // Replace it with your bucket name, which is in the format of BucketName-APPID (APPID is required). It can be viewed in the COS console at https://console.tencentcloud.com/cos5/bucket.
    std::string object_name = "exampleobject"; // `exampleobject` is the ObjectKey (Key), the unique ID of an object in a bucket. For example, if the object's access domain name is `examplebucket-1250000000.cos.ap-guangzhou.myqcloud.com/doc/pic.jpg`, the object key is `doc/pic.jpg`. Replace it with your object name.
    qcloud_cos::PutObjectByFileReq req(bucket_name, object_name, "/path/to/local/file"); // Replace the value with your file path.
    //req.SetXCosStorageClass("STANDARD_IA"); // `STANDARD_IA` is the default value. You can call the `Set` method to set the storage class.
    qcloud_cos::PutObjectByFileResp resp;
    
    // 3. Call the PUT Object API
    qcloud_cos::CosResult result = cos.PutObject(req, &resp);
    
    // 4. Process the call result
    if (result.IsSucc()) {
        // File uploaded successfully
    } else {
        // Failed to upload the file. You can call the `CosResult` member functions to output the error information such as the requestID.
        std::cout << "HttpStatus=" << result.GetHttpStatus() << std::endl;
        std::cout << "ErrorCode=" << result.GetErrorCode() << std::endl;
        std::cout << "ErrorMsg=" << result.GetErrorMsg() << std::endl;
        std::cout << "ResourceAddr=" << result.GetResourceAddr() << std::endl;
        std::cout << "XCosRequestId=" << result.GetXCosRequestId() << std::endl;
        std::cout << "XCosTraceId=" << result.GetXCosTraceId() << std::endl;
    }
}

Querying objects

#include "cos_api.h"
#include "cos_sys_config.h"
#include "cos_defines.h"

int main(int argc, char *argv[]) {
    // 1. Specify the path to the configuration file and initialize CosConfig
    qcloud_cos::CosConfig config("./config.json");
    qcloud_cos::CosAPI cos(config);
    
    // 2. Construct a request to query the object list
    std::string bucket_name = "examplebucket-1250000000"; // Replace it with your bucket name, which is in the format of BucketName-APPID (APPID is required). It can be viewed in the COS console at https://console.tencentcloud.com/cos5/bucket.
    qcloud_cos::GetBucketReq req(bucket_name);
    qcloud_cos::GetBucketResp resp;
    qcloud_cos::CosResult result = cos.GetBucket(req, &resp);   
    
    std::vector<qcloud_cos::Content> cotents = resp.GetContents();
    for (std::vector<qcloud_cos::Content>::const_iterator itr = cotents.begin(); itr != cotents.end(); ++itr) {
        const qcloud_cos::Content& content = *itr;
        std::cout << "key name=" << content.m_key << ", lastmodified ="
            << content.m_last_modified << ", size=" << content.m_size << std::endl;
    }
    
    // 3. Process the call result
    if (result.IsSucc()) {
        // Queried the object list successfully
    } else {
        // Failed to query the object list. You can call the CosResult member functions to output the error information such as requestID.
        std::cout << "HttpStatus=" << result.GetHttpStatus() << std::endl;
        std::cout << "ErrorCode=" << result.GetErrorCode() << std::endl;
        std::cout << "ErrorMsg=" << result.GetErrorMsg() << std::endl;
        std::cout << "ResourceAddr=" << result.GetResourceAddr() << std::endl;
        std::cout << "XCosRequestId=" << result.GetXCosRequestId() << std::endl;
        std::cout << "XCosTraceId=" << result.GetXCosTraceId() << std::endl;
    }
}

Downloading an object

#include "cos_api.h"
#include "cos_sys_config.h"
#include "cos_defines.h"

int main(int argc, char *argv[]) {
    // 1. Specify the path to the configuration file and initialize CosConfig
    qcloud_cos::CosConfig config("./config.json");
    qcloud_cos::CosAPI cos(config);
    
    // 2. Construct a request to download the object
    std::string bucket_name = "examplebucket-1250000000"; // Replace it with your bucket name, which is in the format of BucketName-APPID (APPID is required). It can be viewed in the COS console at https://console.tencentcloud.com/cos5/bucket.
    std::string object_name = "exampleobject"; // `exampleobject` is the ObjectKey (Key), the unique ID of an object in a bucket. For example, if the object's access domain name is `examplebucket-1250000000.cos.ap-guangzhou.myqcloud.com/doc/pic.jpg`, the object key is `doc/pic.jpg`. Replace it with your object name.
    std::string local_path = "/tmp/exampleobject";
    // appid, bucketname, object, and a local path (including filename) are required for the request.
    qcloud_cos::GetObjectByFileReq req(bucket_name, object_name, local_path);
    qcloud_cos::GetObjectByFileResp resp;
    
    // 3. Call the object download API
    qcloud_cos::CosResult result = cos.GetObject(req, &resp);
    
    // 4. Process the call result
    if (result.IsSucc()) {
        // File downloaded successfully
    } else {
        // Failed to download the file. You can call the CosResult member functions to output the error information such as the requestID.
        std::cout << "HttpStatus=" << result.GetHttpStatus() << std::endl;
        std::cout << "ErrorCode=" << result.GetErrorCode() << std::endl;
        std::cout << "ErrorMsg=" << result.GetErrorMsg() << std::endl;
        std::cout << "ResourceAddr=" << result.GetResourceAddr() << std::endl;
        std::cout << "XCosRequestId=" << result.GetXCosRequestId() << std::endl;
        std::cout << "XCosTraceId=" << result.GetXCosTraceId() << std::endl;
    }
}

Deleting an object

#include "cos_api.h"
#include "cos_sys_config.h"
#include "cos_defines.h"

int main(int argc, char *argv[]) {
    // 1. Specify the path to the configuration file and initialize CosConfig
    qcloud_cos::CosConfig config("./config.json");
    qcloud_cos::CosAPI cos(config);
    
    // 2. Construct a request to delete the object
    std::string bucket_name = "examplebucket-1250000000"; // Replace it with your bucket name, which is in the format of BucketName-APPID (APPID is required). It can be viewed in the COS console at https://console.tencentcloud.com/cos5/bucket.
    std::string object_name = "exampleobject"; // `exampleobject` is the ObjectKey (Key), the unique ID of an object in a bucket. For example, if the object's access domain name is `examplebucket-1250000000.cos.ap-guangzhou.myqcloud.com/doc/pic.jpg`, the object key is `doc/pic.jpg`. Replace it with your object name.
    // 3. Call the object deleting API
    qcloud_cos::DeleteObjectReq req(bucket_name, object_name);
    qcloud_cos::DeleteObjectResp resp;
    qcloud_cos::CosResult result = cos.DeleteObject(req, &resp); 
    
    // 4. Process the call result
    if (result.IsSucc()) {
        // Deleted the object successfully
    } else {
        // Failed to delete the object. You can call the CosResult member functions to output the error information such as requestID.
        std::cout << "HttpStatus=" << result.GetHttpStatus() << std::endl;
        std::cout << "ErrorCode=" << result.GetErrorCode() << std::endl;
        std::cout << "ErrorMsg=" << result.GetErrorMsg() << std::endl;
        std::cout << "ResourceAddr=" << result.GetResourceAddr() << std::endl;
        std::cout << "XCosRequestId=" << result.GetXCosRequestId() << std::endl;
        std::cout << "XCosTraceId=" << result.GetXCosTraceId() << std::endl;
    }
}