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本文次要钻研一下mybatis-plus的SafetyEncryptProcessor

SafetyEncryptProcessor

mybatis-plus-boot-starter/src/main/java/com/baomidou/mybatisplus/autoconfigure/SafetyEncryptProcessor.java

public class SafetyEncryptProcessor implements EnvironmentPostProcessor {    @Override    public void postProcessEnvironment(ConfigurableEnvironment environment, SpringApplication application) {        /**         * 命令行中获取密钥         */        String mpwKey = null;        for (PropertySource<?> ps : environment.getPropertySources()) {            if (ps instanceof SimpleCommandLinePropertySource) {                SimpleCommandLinePropertySource source = (SimpleCommandLinePropertySource) ps;                mpwKey = source.getProperty("mpw.key");                break;            }        }        /**         * 解决加密内容         */        if (StringUtils.isNotBlank(mpwKey)) {            HashMap<String, Object> map = new HashMap<>();            for (PropertySource<?> ps : environment.getPropertySources()) {                if (ps instanceof OriginTrackedMapPropertySource) {                    OriginTrackedMapPropertySource source = (OriginTrackedMapPropertySource) ps;                    for (String name : source.getPropertyNames()) {                        Object value = source.getProperty(name);                        if (value instanceof String) {                            String str = (String) value;                            if (str.startsWith("mpw:")) {                                map.put(name, AES.decrypt(str.substring(4), mpwKey));                            }                        }                    }                }            }            // 将解密的数据放入环境变量，并处于第一优先级上            if (CollectionUtils.isNotEmpty(map)) {                environment.getPropertySources().addFirst(new MapPropertySource("custom-encrypt", map));            }        }    }}
SafetyEncryptProcessor实现了EnvironmentPostProcessor接口，在postProcessEnvironment办法中先是找到mpw.key，而后遍历所有PropertySource的所有属性，找到mpw:结尾的，而后进行解密并替换到密文，最初放在environment的第一个PropertySource

spring.factories

mybatis-plus-boot-starter/src/main/resources/META-INF/spring.factories

# Auto Configureorg.springframework.boot.env.EnvironmentPostProcessor=\  com.baomidou.mybatisplus.autoconfigure.SafetyEncryptProcessor

小结

之前的文章聊聊springboot的EnvironmentPostProcessor提到springboot提供了EnvironmentPostProcessor接口，该接口有postProcessEnvironment办法，其中envrionment参数类型为ConfigurableEnvironment，即利用能够通过实现这个接口进行env环境变量的操作。而mybatis-plus的SafetyEncryptProcessor正是一个实战的好例子。