好久没更博了...
最近看了个真正全注解实现的 SpringMVC 博客,感觉很不错,终于可以彻底丢弃 web.xml
了。其实这玩意也是老东西了,丢弃 web.xml
,是基于 5、6年前发布的 Servlet 3.0 规范,只不过少有人玩而已...现在4.0都快正式发布了...Spring对注解的支持也从09年底就开始支持了...
基础部分我就不仔细讲了,可以先看一下这篇 以及其中提到的另外两篇文章,这三篇文章讲的很不错。
下面开始旧东西新玩~~~
构建
项目是基于 gradle 3.1
构建的,这是项目依赖:
dependencies {
def springVersion = '4.3.2.RELEASE'
compile "org.springframework:spring-web:$springVersion"
compile "org.springframework:spring-webmvc:$springVersion"
compile "redis.clients:jedis:2.9.0"
compile "javax.servlet:javax.servlet-api:3.1.0"
compile "org.json:json:20160810"
}
编写Java版的web.xml
想要让请求经过Java,少不了配置 web.xml
,不过现在我们来写个Java版的~
这里和传统的 web.xml
一样,依次添加 filter
, servlet
。
package org.xueliang.loginsecuritybyredis.commons;
import javax.servlet.FilterRegistration;
import javax.servlet.Servlet;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;
import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.filter.CharacterEncodingFilter;
import org.springframework.web.servlet.DispatcherServlet;
/**
* 基于注解的/WEB-INF/web.xml
* 依赖 servlet 3.0
* @author XueLiang
* @date 2016年10月24日 下午5:58:45
* @version 1.0
*/
public class CommonInitializer implements WebApplicationInitializer {
@Override
public void onStartup(ServletContext servletContext) throws ServletException {
// 基于注解配置的Web容器上下文
AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();
context.register(WebAppConfig.class);
// 添加编码过滤器并进行映射
CharacterEncodingFilter characterEncodingFilter = new CharacterEncodingFilter("UTF-8", true);
FilterRegistration.Dynamic dynamicFilter = servletContext.addFilter("characterEncodingFilter", characterEncodingFilter);
dynamicFilter.addMappingForUrlPatterns(null, true, "/*");
// 添加静态资源映射
ServletRegistration defaultServletRegistration = servletContext.getServletRegistration("default");
defaultServletRegistration.addMapping("*.html");
Servlet dispatcherServlet = new DispatcherServlet(context);
ServletRegistration.Dynamic dynamicServlet = servletContext.addServlet("dispatcher", dispatcherServlet);
dynamicServlet.addMapping("/");
}
}
这一步走完,Spring 基本上启动起来了。
编写Java版的Spring配置
现在Spring已经可以正常启动了,但我们还要给 Spring 做一些配置,以便让它按我们需要的方式工作~
这里因为后端只负责提供数据,而不负责页面渲染,所以只需要配置返回 json
视图即可,个人比较偏爱采用内容协商,所以这里我使用了 ContentNegotiationManagerFactoryBean
,但只配置了一个 JSON 格式的视图。
为了避免中文乱码,这里设置了 StringHttpMessageConverter
默认编码格式为 UTF-8
,然后将其设置为 RequestMappingHandlerAdapter
的消息转换器。
最后还需要再配置一个欢迎页,类似于 web.xml
的 welcome-file-list - welcome-file
,因为 Servlet 3.0 规范没有针对欢迎页的Java配置方案,所以目前只能在Java中这样配置,其效果类似于在XML版中配置 <mvc:redirect-view-controller path="/" redirect-url="/index.html"/>
。
最后注意这里的 @Bean
注解,默认的 name
是方法名。
package org.xueliang.loginsecuritybyredis.commons;
import java.nio.charset.Charset;
import java.util.Collections;
import java.util.Properties;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.http.MediaType;
import org.springframework.http.converter.StringHttpMessageConverter;
import org.springframework.web.accept.ContentNegotiationManager;
import org.springframework.web.accept.ContentNegotiationManagerFactoryBean;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter;
import org.springframework.web.servlet.view.ContentNegotiatingViewResolver;
@Configuration
@EnableWebMvc
@ComponentScan(basePackages = "org.xueliang.loginsecuritybyredis")
@PropertySource({"classpath:loginsecuritybyredis.properties"})
public class WebAppConfig extends WebMvcConfigurerAdapter {
/**
* 内容协商
* @return
*/
@Bean
public ContentNegotiationManager mvcContentNegotiationManager() {
ContentNegotiationManagerFactoryBean contentNegotiationManagerFactoryBean = new ContentNegotiationManagerFactoryBean();
contentNegotiationManagerFactoryBean.setFavorParameter(true);
contentNegotiationManagerFactoryBean.setIgnoreAcceptHeader(true);
contentNegotiationManagerFactoryBean.setDefaultContentType(MediaType.APPLICATION_JSON_UTF8);
Properties mediaTypesProperties = new Properties();
mediaTypesProperties.setProperty("json", MediaType.APPLICATION_JSON_UTF8_VALUE);
contentNegotiationManagerFactoryBean.setMediaTypes(mediaTypesProperties);
contentNegotiationManagerFactoryBean.afterPropertiesSet();
return contentNegotiationManagerFactoryBean.getObject();
}
@Bean
public ContentNegotiatingViewResolver contentNegotiatingViewResolver(@Autowired ContentNegotiationManager mvcContentNegotiationManager) {
ContentNegotiatingViewResolver contentNegotiatingViewResolver = new ContentNegotiatingViewResolver();
contentNegotiatingViewResolver.setOrder(1);
contentNegotiatingViewResolver.setContentNegotiationManager(mvcContentNegotiationManager);
return contentNegotiatingViewResolver;
}
/**
* 采用UTF-8编码,防止中文乱码
* @return
*/
@Bean
public StringHttpMessageConverter stringHttpMessageConverter() {
return new StringHttpMessageConverter(Charset.forName("UTF-8"));
}
@Bean
public RequestMappingHandlerAdapter requestMappingHandlerAdapter(@Autowired StringHttpMessageConverter stringHttpMessageConverter) {
RequestMappingHandlerAdapter requestMappingHandlerAdapter = new RequestMappingHandlerAdapter();
requestMappingHandlerAdapter.setMessageConverters(Collections.singletonList(stringHttpMessageConverter));
return requestMappingHandlerAdapter;
}
/**
* 设置欢迎页
* 相当于web.xml中的 welcome-file-list > welcome-file
*/
@Override
public void addViewControllers(ViewControllerRegistry registry) {
registry.addRedirectViewController("/", "/index.html");
}
}
编写登录认证Api
这里在 init
方法中初始化几个用户,放入 USER_DATA
集合,用于后续模拟登录。然后初始化 jedis
连接信息。init
方法被 @PostConstruct
注解,因此 Spring
创建该类的对象后,将自动执行其 init
方法,进行初始化操作。
然后看 login
方法,首先根据用户名获取最近 MAX_DISABLED_SECONDS
秒内失败的次数,是否超过最大限制 MAX_TRY_COUNT
。
若超过最大限制,不再对用户名和密码进行认证,直接返回认证失败提示信息,也即账户已被锁定的提示信息。
否则,进行用户认证。
若认证失败,将其添加到 Redis 缓存中,并设置过期默认为 MAX_DISABLED_SECONDS
,表示从此刻起,MAX_DISABLED_SECONDS
秒内,该用户已登录失败 count
次。
若Redis缓存中已存在该用户认证失败的计数信息,则刷新 count
值,并将旧值的剩余存活时间设置到新值上,然后返回认证失败提示信息。
否则,返回认证成功提示信息。
package org.xueliang.loginsecuritybyredis.web.controller.api;
import java.util.HashMap;
import java.util.Map;
import javax.annotation.PostConstruct;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.xueliang.loginsecuritybyredis.web.model.JSONResponse;
import org.xueliang.loginsecuritybyredis.web.model.User;
import redis.clients.jedis.Jedis;
/**
* 认证类
* @author XueLiang
* @date 2016年11月1日 下午4:11:59
* @version 1.0
*/
@RestController
@RequestMapping("/api/auth/")
public class AuthApi {
private static final Map<String, User> USER_DATA = new HashMap<String, User>();
@Value("${auth.max_try_count}")
private int MAX_TRY_COUNT = 0;
@Value("${auth.max_disabled_seconds}")
private int MAX_DISABLED_SECONDS = 0;
@Value("${redis.host}")
private String host;
@Value("${redis.port}")
private int port;
private Jedis jedis;
@PostConstruct
public void init() {
for (int i = 0; i < 3; i++) {
String username = "username" + 0;
String password = "password" + 0;
USER_DATA.put(username + "_" + password, new User(username, "nickname" + i));
}
jedis = new Jedis(host, port);
}
@RequestMapping(value = {"login"}, method = RequestMethod.POST)
public String login(@RequestParam("username") String username, @RequestParam("password") String password) {
JSONResponse jsonResponse = new JSONResponse();
String key = username;
String countString = jedis.get(key);
boolean exists = countString != null;
int count = exists ? Integer.parseInt(countString) : 0;
if (count >= MAX_TRY_COUNT) {
checkoutMessage(key, count, jsonResponse);
return jsonResponse.toString();
}
User user = USER_DATA.get(username + "_" + password);
if (user == null) {
count++;
int secondsRemain = MAX_DISABLED_SECONDS;
if (exists && count < 5) {
secondsRemain = (int)(jedis.pttl(key) / 1000);
}
jedis.set(key, count + "");
jedis.expire(key, secondsRemain);
checkoutMessage(key, count, jsonResponse);
return jsonResponse.toString();
}
count = 0;
if (exists) {
jedis.del(key);
}
checkoutMessage(key, count, jsonResponse);
return jsonResponse.toString();
}
/**
*
* @param key
* @param count 尝试次数,也可以改为从redis里直接读
* @param jsonResponse
* @return
*/
private void checkoutMessage(String key, int count, JSONResponse jsonResponse) {
if (count == 0) {
jsonResponse.setCode(0);
jsonResponse.addMsg("success", "恭喜,登录成功!");
return;
}
jsonResponse.setCode(1);
if (count >= MAX_TRY_COUNT) {
long pttlSeconds = jedis.pttl(key) / 1000;
long hours = pttlSeconds / 3600;
long sencondsRemain = pttlSeconds - hours * 3600;
long minutes = sencondsRemain / 60;
long seconds = sencondsRemain - minutes * 60;
jsonResponse.addError("login_disabled", "登录超过" + MAX_TRY_COUNT + "次,请" + hours + "小时" + minutes + "分" + seconds + "秒后再试!");
return;
}
jsonResponse.addError("username_or_password_is_wrong", "密码错误,您还有 " + (MAX_TRY_COUNT - count) + " 次机会!");
}
}
编写前端页面
页面很简单,监听表单提交事件,用 ajax 提交表单数据,然后将认证结果显示到 div
中。
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>登录</title>
<style>
span.error {
color: red;
}
span.msg {
color: green;
}
</style>
</head>
<body>
<form action="" method="post">
<label>用户名</label><input type="text" name="username">
<label>密码</label><input type="text" name="password">
<button type="submit">登录</button>
<div></div>
</form>
<script>
(function($) {
var $ = (selector) => document.querySelector(selector);
var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
var response = JSON.parse(this.responseText);
var html = '';
var msgNode = '';
if (response.code != 0) {
msgNode = 'error';
} else {
msgNode = 'msg';
}
for (var key in response[msgNode]) {
html += '<span class="' + msgNode + '">' + response[msgNode][key] + '</span>';
}
$('div').innerHTML = html;
}
}
var ajax = function(formData) {
xhr.open('POST', '/api/auth/login.json', true);
xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8'); // 将请求头设置为表单方式提交
xhr.send(formData);
}
$('form').addEventListener('submit', function(event) {
event.preventDefault();
var formData = '';
for (var elem of ['username', 'password']) {
var value = $('input[name="' + elem + '"]').value;
formData += (elem + '=' + value + '&');
}
ajax(formData);
});
})();
</script>
</body>
</html>
源码
最后上下源码地址:https://github.com/liangzai-cool/loginsecuritybyredis
更新
2016年11月29日 更新,代码优化,增加原子操作,org.xueliang.loginsecuritybyredis.web.controller.api.AuthApi#login
函数作如下优化:
@RequestMapping(value = {"login"}, method = RequestMethod.POST)
public String login(@RequestParam("username") String username, @RequestParam("password") String password) {
JSONResponse jsonResponse = new JSONResponse();
String key = username;
String countString = jedis.get(key);
boolean exists = countString != null;
int count = exists ? Integer.parseInt(countString) : 0;
if (count >= MAX_TRY_COUNT) {
checkoutMessage(key, count, jsonResponse);
return jsonResponse.toString();
}
User user = USER_DATA.get(username + "_" + password);
if (user == null) {
count++;
// int secondsRemain = MAX_DISABLED_SECONDS;
// if (exists && count < 5) {
// secondsRemain = (int)(jedis.pttl(key) / 1000);
// }
// jedis.set(key, count + "");
// jedis.expire(key, secondsRemain);
if (exists) {
jedis.incr(key);
if (count >= MAX_TRY_COUNT) {
jedis.expire(key, MAX_DISABLED_SECONDS);
}
} else {
jedis.set(key, count + "");
jedis.expire(key, MAX_DISABLED_SECONDS);
}
checkoutMessage(key, count, jsonResponse);
return jsonResponse.toString();
}
count = 0;
if (exists) {
jedis.del(key);
}
checkoutMessage(key, count, jsonResponse);
return jsonResponse.toString();
}
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来通知其他用户。