How to use PHP cache development to improve website security

With the popularity of the Internet, more and more websites and applications have emerged, most of which need to interact with databases. However, frequent access to the database will have a great impact on the performance of the website. In order to solve this problem, we can use caching to improve the access speed and security of the website. The following will introduce how to use PHP to develop cache to improve the security of the website, and illustrate it through specific code examples.

1. Why do you need caching?

In traditional website applications, every time the client makes a request, the application server usually queries the database for data, which will generate a lot of database access requests. When the number of concurrent users increases, the pressure on accessing the database will also increase, thus reducing the access speed of the website. Moreover, since data access to the database is uncontrollable, there may be risks of malicious attacks or illegal operations.

In order to solve these problems, we can use caching technology. Caching refers to storing commonly used data in memory so that it can be read and accessed quickly. Through caching technology, websites can reduce the access pressure on the database, improve access speed, and protect the security of the database.

2. Implementation of PHP caching technology

In PHP, there are many ready-made caching technologies available, such as APC, Memcache, Redis, etc. The implementation of these technologies varies, but the basic idea is similar, that is, storing frequently used data in memory to increase access speed and reduce database pressure. Below, we take APC caching as an example to introduce how to use PHP caching technology to improve website security.

1. Installing APC

Before using APC technology, it needs to be installed and enabled on the server. APC can be installed through the following command:

sudo apt-get install php-apcu

After the installation is completed, you need to enable the APC module in the php.ini file (usually in /etc/php/7.0/fpm/php.ini) and replace the following code Add to the bottom of the file:

extension=apcu.so
apc.enabled=1

Then restart the PHP service:

sudo systemctl restart php7.0-fpm

2. Write caching code

Before using APC caching technology, you need to detect whether the cache is Available. The following code can be used to detect:

if(!function_exists('apc_store')){
    echo 'APC Cache Not Available';
    exit;
}

Then, the apc_store() function can be used to store data into the APC cache:

if(!apc_exists('my_cache_key')){
    $cache = 'This data will be cached';
    //存储数据
    apc_store('my_cache_key', $cache, 300);
}else{
    //从缓存中获取数据
    echo 'Data from Cache : '.apc_fetch('my_cache_key');
}

In the above code, the apc_store() function is used Store data in the cache. Parameter 1 specifies the unique key value of the cached data. Parameter 2 is the data to be cached. Parameter 3 specifies the cache time (seconds) of the data. If the apc_fetch() function finds the corresponding cached data, it will return the cached data.

3. Use caching technology to protect website security

In addition to improving the access speed of the website, caching technology can also improve the security of the website. For example, if there is an API that requires key verification, we can cache the verification results to reduce database access requests for each verification. In addition, if the passwords stored in the database are in clear text, to improve security, the MD5 hash value or other encrypted value of the password can be cached in memory.

The following is an example of using caching technology to protect API security:

function validate_key($api_key){
    if(apc_exists($api_key)){
        //从缓存中获取验证结果
        return apc_fetch($api_key);
    }else{
        //在数据库中验证API密钥
        $result = verify_api_key($api_key);
        //将验证结果缓存起来，缓存时间为30秒
        apc_store($api_key, $result, 30);
        return $result;
    }
}

In the above code, the function validate_key() is used to verify the API key. If the key value exists in the APC cache, the verification result will be obtained from the cache, otherwise it will be verified in the database, and then the result will be stored in the APC cache and returned.

3. Summary

Using caching technology can greatly improve the access speed and security of the website and reduce the pressure of database access. In PHP, you can choose from a variety of caching technologies, such as APC, Memcache, Redis, etc. When using caching technology, you need to pay attention to caching time and caching conditions to avoid cache invalidation or storage of useless data, which will reduce website security.

The above is the detailed content of How to use PHP cache development to improve website security. For more information, please follow other related articles on the PHP Chinese website!