每特教育学院蚂蚁课堂-3期分布式解决方案彻底解决网站跨域求

客户对向服务器端发送请求后，SessionSessionid给客户端浏览器sessionId获取对应的从服务器上获取对应的SesisonSession保证在那里关闭浏览器Session会失效吗相关代创建session会@RequestMappublicStringcreateSession(HttpServletRequestrequest,StringnameValue)HttpSessionsession=System.out.println("存入Sessionsessionid:信息session.getId()",nameValue:"nameValue);session.setAttribute("name",nameValue);returnreturn} publicObjectgetSession(HttpServletRequestrequest)HttpSessionsession=System.out.println("获取Sessionsessionid:信息"+Objectvalue=return}publicstaticvoidmain(String[]args)SpringApplication.run(TestSessionController.class,}}Nginx配置Nginx负载均衡提供上游服务器(真实业务逻辑的服务器),负载均衡故障转移失败重试容错健康检查等。当上游服务器(真实业务逻辑的服务器)发生故障时，可以转移到其他上游服务器(真实业务逻辑的服务器)。UpstreamServerupstream要配置如下IP地址和端：配置上游服务器的IP地址和端###定义上###定义上游服务器(需要被nginx真的服务器)默认是轮训机backServer{server127001:8080;server12700serverserver_namewwwitmayiedulocation/###指定上游服务器负载均衡服务;indexindexhtmlindex}}负载均衡算法轮询（默认每个请求按时间顺序逐一分配到不同的后端服务，如果后端某台服务器死机，自动剔除故障系统，使用户不受影响weight（轮询权值weigt的值越大分配到的概率越高，主要用于后端每台服务器性能不均衡的情况下。或者仅仅为在主从的情况下设置不同的权值，达到合理有效的地利用主机资源。每个请求按IP的哈希结果分配，使来自同一个IP的访客固定一台后端服务器，并且可以有效解决页session享问题IPfair（第比weihtip_hah更加智能的负载均衡算法，fair算法可以根据页面大小和加载时间长短智能地进行负载均衡，也就是根据后端服务器的响应时间来分配请求，响应时间短的优先分配。Nginx本身不支持fair，如果需要这种调度算法，则必须安装upstream_far模块。url_hash(第按的URL的希结果来分配请求，使每个URL定到台服器可进步高缓服器效Nginx本身不支持url_hsh，如果需要这种调度算法，则必须安装Nginx的ash包。privateStringpublicStringindex()return}创建session会publicStringcreateSession(HttpServletRequestrequest,StringnameValue)HttpSessionsession=session.setAttribute("name",return"success-"+} publicObjectgetSession(HttpServletRequestrequest)HttpSessionsession=if(session==null)returnserverPort+"没有找到对应的session值}Objectvalue=returnserverPort+"-"+}publicstaticvoidmain(String[]args)SpringApplication.run(TestSessionController.class,}}nginxhaproxyIP利用数据库同步使用Session集群存放maven <artifactId>spring-boot-starter-<relativePath/><!--lookupparentfromrepository--<weixin-java-mp.version>2.8.0</weixin-java-<<><piler.encoding>UTF-<project.build.sourceEncoding>UTF- <artifactId>spring-boot-starter-<!--<exclusions><exclusion><artifactId>jackson-databind</artifactId></exclusion></exclusions>--<!-- .alibaba/fastjson--<!--TestingDependencies-- <artifactId>spring-boot-starter- <artifactId>spring-boot-starter-data-<!--springsessionredis应用基本环境配置,需要开启redis后才Spring会报错 <artifactId>spring-session-data- <artifactId>commons- piler- <artifactId>spring-boot-maven-YML配置信port:/ importimport//这个类用配置redis服务器的连接//maxInactiveIntervalInSeconds为SpringSession的过期时间（单位：秒@EnableRedisHttpSession(maxInactiveIntervalInSeconds=publicclassSessionConfig//StringintpublicJedisConnectionFactoryconnectionFactory()JedisConnectionFactoryconnection=newreturn}}初始////初始化Session配置publicclassSessionInitializerpublicpublic{}}最靠谱的分布式Session解决方publicclassTokenServiceprivateRedisService新增返回publicStringput(Objectobject)Stringtoken=redisService.setString(token,return}获取信publicStringget(Stringtoken)Stringreuslt=return}publicpublicStringgetToken()return}}privateTokenServiceprivateStringpublicStringput(StringnameValue)Stringtoken=returntoken+"-"+}publicStringget(Stringtoken)Stringvalue=returnvalue+"-"+}}跨域报 :8081/ajaxB:No'Access-Control-Allow-Origin'headerispresentontherequestedresource.Origin'http :8080'isthereforenotallowedaccess.五种跨域解决方使用JSONP解决跨前端代<<scriptmon/jquery-1.7.2.min.js?t=2017-07-<script).ready(function()type:async:url:dataType:jsonp:" allback",//服务端用于接收callback调用的functionsuccess:function(data)error:function()}后端代 (value="/ajaxB",method=public JSONObjectroot=newroot.put("errorCode",root.put("errorMsg","登陆成功response.setHeader("Content- "text/html;charset=UTF-PrintWriterwriter= allback+"("+root.toString()+}使用设置响应头允许跨域前端代<<scriptmon/jquery-1.7.2.min.js?t=2017-07-<script).ready(function()type:async:url:dataTypedataType:success:function(data)error:function()}后端代 publicMap<String,Object>ajaxB(HttpServletResponseresponse)response.setHeader("Access-Control-Allow-Origin",Map<String,Object>result=newHashMap<String,result.put("errorMsg","登陆成功return}response.setHeader("Access-Control-Allow-Origin","*");使用HttpClient进行转前端代<<scriptmon/jquery-1.7.2.min.js?t=2017-07-<script).ready(function()type:async:url:dataType:success:function(data)error:function()}后端代 publicJSONObjectforwardB()JSONObjectresult=System.out.println("result:"+return} publicMap<String,Object>ajaxB(HttpServletResponseresponse)response.setHeader("Access-Control-Allow-Origin",Map<String,Object>result=newHashMap<String,result.put("errorMsg","登陆成功return}搭建企业级API接口使用NginxAPI接口网Nginx相关配serverserverlocation/a index.html}###Blocation/b index.html}}前端代码<<script /jquery-<script ).ready(function()type:async:url:dataType:success:function(data)errorerror:function()}后端代码 publicMap<String,Object>ajaxB(HttpServletResponse{response.setHeader("Access-Control-Allow-Origin","*");Map<String,Object>result=newHashMap<String,Object>();result.put("errorCode","200");result.put("errorMsg","登陆成功}SpringCloud搭建API接口网Maven初始化依赖参数 <artifactId>spring-boot-starter-SpringBootlombok<groupId><!--SpringBootweb组件--<groupId><artifactId>spring-boot-starter-<groupId><artifactId>spring-boot-starter-SpringBoot外部tomcat支持<groupId><artifactId>tomcat-embed-<!--<!--springboot-log4j-- <artifactId>spring-boot-starter- <artifactId>spring-boot-starter-<!-- .alibaba/fastjson--port:port:prefix:/WEB-suffix:HttpClientUtils工具privatestaticLoggerlogger=LoggerFactory.getLogger(HttpClientUtils.class);//日志记privatestaticonfigonfig=static//设置请求和传输超时onfig=}*post请求传输json参**@param*url*@param*参*//post请求返回结CloseableHttpClienthttpClient=JSONObjectjsonResult=HttpPosthttpPost=new//设置请求和传输超时 tryif(null!=jsonParam)//解决中文乱码问StringEntityentity=newStringEntity(jsonParam.toString(),"utf-entity.setContentEncoding("UTF-}CloseableHttpResponseresult=//请求发送成功，并得到响if(result.getStatusLine().getStatusCode()==HttpStatus.SC_OK)Stringstr=try 服务器返回过来的jsonstr=EntityUtils.toString(result.getEntity(),"utf-//json字符串转换成json对jsonResult=}catch(Exceptione)}}}catch(IOExceptione)logger.error("post请求提交失败:"+url,}finally}return}post请求传输String参数Content-type:application/x-www-form-@paramurl@param参publicstaticJSONObjecthttpPost(Stringurl,StringstrParam)//post请求返回结CloseableHttpClienthttpClient=JSONObjectjsonResult=HttpPosthttpPost=new tryif(null!=strParam)//解决中文乱码问StringEntityentity=newStringEntity(strParam,"utf-entity.setContentEncoding("UTF-entity.setContentType("application/x-www-form-}CloseableHttpResponseresult=//请求发送成功，并得到响if(result.getStatusLine().getStatusCode()==HttpStatus.SC_OK)Stringstr=try 服务器返回过来的jsonstr=EntityUtils.toString(result.getEntity(),"utf-//json字符串转换成json对jsonResult=}catch(Exceptione)}}}catch(IOExceptione)logger.err