项目背景
- 前后端分离
- 负载均衡
- gateway转发
使用
基于springboot
<dependency>
<groupId>org.jasig.cas.client</groupId>
<artifactId>cas-client-support-springboot</artifactId>
<version>3.6.1</version>
</dependency>
基本的接入
// 注册验证bean
@Bean
public FilterRegistrationBean filterAuthenticationRegistration() {
FilterRegistrationBean registration = new FilterRegistrationBean();
registration.setFilter(new AuthenticationFilter());
registration.addUrlPatterns("/*");
Map<String, String> initParameters = new HashMap<String, String>(3);
initParameters.put("casServerLoginUrl", casProperties.getCasServerUrl());
initParameters.put("serverName", casProperties.getClientHostUrl());
// 自定义重定向策略
initParameters.put("authenticationRedirectStrategyClass", "package.CustomAuthenticationRedirectStrategy");
initParameters.put("ignorePattern", casProperties.getIgnoreUrl());
registration.setInitParameters(initParameters);
registration.setOrder(1);
return registration;
}
配置信息
cas:
server-url-prefix: http://cas-server-url
server-login-url: http://cas-server-url/login
client-host-url: http://cas-client-application-host // cas服务器通过这个关联ticket信息，需要保证后续请求cas服务器的host都是这个
validation-type: CAS
接入中遇到的问题
前后端分离
- 未登录情况下，前端处理重定向地址
通过自定义重定向策略实现返回json给前端值跳转，与前端约定规则做跳转即可
public class CustomAuthenticationRedirectStrategy implements AuthenticationRedirectStrategy {
@Override
public void redirect(final HttpServletRequest request, final HttpServletResponse response,
final String potentialRedirectUrl) throws IOException {
CasProperties casProperties = SpringUtils.getBean("casProperties", CasProperties.class);
response.setContentType("application/json");
response.setStatus(401);
BaseResponse baseResponse = BaseResponse.success();
baseResponse.setCode(10401);
Map<String, String> re = new HashMap<>(2);
// 封转 返回重定向地址：cas登录的地址，service 为后端接口，用作登录成功后跳转到前端页面逻辑处理
re.put("redirect", casProperties.getCasServerLoginUrl() + "?service=" + casProperties.getClientHostUrl()+"/cas");
baseResponse.setData(re);
try (
final PrintWriter writer = response.getWriter()
) {
writer.write(new ObjectMapper().writeValueAsString(baseResponse));
writer.flush();
}
}
}
- 负载均衡
由于cas是使用session做票据的存储，当架构为nginx负载多台服务器情况下，需要做session共享处理，否则一台机子有票据信息，一台没有，当同一个用的的请求负载到不同服务器会出现登录失败情况。
- gateway 条状的架构
gateway条状的情况下使用的服务调用，目前的实现方式都是调用注册中心的服务列表，使用ip:port的形式调用。查看源码AbstractTicketValidationFilter源码
@Override
public final void doFilter(final ServletRequest servletRequest, final ServletResponse servletResponse,
final FilterChain filterChain) throws IOException, ServletException {
// 省略代码...
try {
// 问题在这里的url校验，构造之后url会待上端口信息，导致在cas服务器上校验不通过
final Assertion assertion = this.ticketValidator.validate(ticket,
constructServiceUrl(request, response));
} catch (final TicketValidationException e) {
// ...
}
filterChain.doFilter(request, response);
}
直接看CommonUtils.constructServiceUrl
public static String constructServiceUrl(final HttpServletRequest request, final HttpServletResponse response,
final String service, final String serverNames, final String serviceParameterName,
final String artifactParameterName, final boolean encode) {
if (CommonUtils.isNotBlank(service)) {
return encode ? response.encodeURL(service) : service;
}
final String serverName = findMatchingServerName(request, serverNames);
final URIBuilder originalRequestUrl = new URIBuilder(request.getRequestURL().toString(), encode);
originalRequestUrl.setParameters(request.getQueryString());
final URIBuilder builder;
if (!serverName.startsWith("https://") && !serverName.startsWith("http://")) {
final String scheme = request.isSecure() ? "https://" : "http://";
builder = new URIBuilder(scheme + serverName, encode);
} else {
builder = new URIBuilder(serverName, encode);
}
// 判断了端口不是80，443就拼接上端口
if (builder.getPort() == -1 && !requestIsOnStandardPort(request)) {
builder.setPort(request.getServerPort());
}
builder.setEncodedPath(builder.getEncodedPath() + request.getRequestURI());
final List<String> serviceParameterNames = Arrays.asList(serviceParameterName.split(","));
if (!serviceParameterNames.isEmpty() && !originalRequestUrl.getQueryParams().isEmpty()) {
for (final URIBuilder.BasicNameValuePair pair : originalRequestUrl.getQueryParams()) {
final String name = pair.getName();
if (!name.equals(artifactParameterName) && !serviceParameterNames.contains(name)) {
if (name.contains("&") || name.contains("=")) {
final URIBuilder encodedParamBuilder = new URIBuilder();
encodedParamBuilder.setParameters(name);
for (final URIBuilder.BasicNameValuePair pair2 : encodedParamBuilder.getQueryParams()) {
final String name2 = pair2.getName();
if (!name2.equals(artifactParameterName) && !serviceParameterNames.contains(name2)) {
builder.addParameter(name2, pair2.getValue());
}
}
} else {
builder.addParameter(name, pair.getValue());
}
}
}
}
final String result = builder.toString();
final String returnValue = encode ? response.encodeURL(result) : result;
LOGGER.debug("serviceUrl generated: {}", returnValue);
return returnValue;
}
直接下载源码改写
总结
基于公司项目的接入情况遇到的问题解决。相对于前期接入方案较单一，从而导致接入过程磕磕绊绊，记录一下。
