Soul源码阅读 SpringCloud集成原理2【第十五天】

springcloud是如何进行调用的

SpringCloudPlugin中进行调用，核心代码如下

@Override
    // 执行代理调用
    protected Mono doExecute(final ServerWebExchange exchange, final SoulPluginChain chain, final SelectorData selector, final RuleData rule) {
        // 如果没有规则，直接返回空
        if (Objects.isNull(rule)) {
            return Mono.empty();
        }
        // 获取soul全局context
        final SoulContext soulContext = exchange.getAttribute(Constants.CONTEXT);
        assert soulContext != null;
        // springcloud规则
        final SpringCloudRuleHandle ruleHandle = GsonUtils.getInstance().fromJson(rule.getHandle(), SpringCloudRuleHandle.class);
        // 选择器
        final SpringCloudSelectorHandle selectorHandle = GsonUtils.getInstance().fromJson(selector.getHandle(), SpringCloudSelectorHandle.class);
        // 选择器和规则都不存在
        if (StringUtils.isBlank(selectorHandle.getServiceId()) || StringUtils.isBlank(ruleHandle.getPath())) {
            // 返回错误信息
            Object error = SoulResultWrap.error(SoulResultEnum.CANNOT_CONFIG_SPRINGCLOUD_SERVICEID.getCode(), SoulResultEnum.CANNOT_CONFIG_SPRINGCLOUD_SERVICEID.getMsg(), null);
            return WebFluxResultUtils.result(exchange, error);
        }
        // 负载均衡选择一个实例
        final ServiceInstance serviceInstance = loadBalancer.choose(selectorHandle.getServiceId());
        // 如果负载均衡选择的实例是空
        if (Objects.isNull(serviceInstance)) {
            // 返回错误信息
            Object error = SoulResultWrap.error(SoulResultEnum.SPRINGCLOUD_SERVICEID_IS_ERROR.getCode(), SoulResultEnum.SPRINGCLOUD_SERVICEID_IS_ERROR.getMsg(), null);
            return WebFluxResultUtils.result(exchange, error);
        }
        // 获取uri
        final URI uri = loadBalancer.reconstructURI(serviceInstance, URI.create(soulContext.getRealUrl()));
        //获取真实的url地址
        String realURL = buildRealURL(uri.toASCIIString(), soulContext.getHttpMethod(), exchange.getRequest().getURI().getQuery());
        // 存储需要执行调用的信息到exchange
        exchange.getAttributes().put(Constants.HTTP_URL, realURL);
        //set time out.
        exchange.getAttributes().put(Constants.HTTP_TIME_OUT, ruleHandle.getTimeout());
        return chain.execute(exchange);
    }

WebClientPlugin执行请求

 @Override
    public Mono execute(final ServerWebExchange exchange, final SoulPluginChain chain) {
        // 获取soulcontext
        final SoulContext soulContext = exchange.getAttribute(Constants.CONTEXT);
        assert soulContext != null;
        // 获取请求的url
        String urlPath = exchange.getAttribute(Constants.HTTP_URL);
        if (StringUtils.isEmpty(urlPath)) {
            // 如果是空，返回错误信息
            Object error = SoulResultWrap.error(SoulResultEnum.CANNOT_FIND_URL.getCode(), SoulResultEnum.CANNOT_FIND_URL.getMsg(), null);
            return WebFluxResultUtils.result(exchange, error);
        }
        // 超时时间
        long timeout = (long) Optional.ofNullable(exchange.getAttribute(Constants.HTTP_TIME_OUT)).orElse(3000L);
        // 重试册数
        int retryTimes = (int) Optional.ofNullable(exchange.getAttribute(Constants.HTTP_RETRY)).orElse(0);
        log.info("The request urlPath is {}, retryTimes is {}", urlPath, retryTimes);
        // 方法
        HttpMethod method = HttpMethod.valueOf(exchange.getRequest().getMethodValue());
        // 执行方法
        WebClient.RequestBodySpec requestBodySpec = webClient.method(method).uri(urlPath);
        return handleRequestBody(requestBodySpec, exchange, timeout, retryTimes, chain);
    }

WebClientResponsePlugin返回请求结果

@Override
    public Mono execute(final ServerWebExchange exchange, final SoulPluginChain chain) {
        return chain.execute(exchange).then(Mono.defer(() -> {
            // 请求返回结果
            ServerHttpResponse response = exchange.getResponse();
            // 客户端返回
            ClientResponse clientResponse = exchange.getAttribute(Constants.CLIENT_RESPONSE_ATTR);
            // 如果返回结果为空，状态为失败，返回错误信息
            if (Objects.isNull(clientResponse)
                    || response.getStatusCode() == HttpStatus.BAD_GATEWAY
                    || response.getStatusCode() == HttpStatus.INTERNAL_SERVER_ERROR) {
                Object error = SoulResultWrap.error(SoulResultEnum.SERVICE_RESULT_ERROR.getCode(), SoulResultEnum.SERVICE_RESULT_ERROR.getMsg(), null);
                return WebFluxResultUtils.result(exchange, error);
            }
            // 超时，返回超时错误
            if (response.getStatusCode() == HttpStatus.GATEWAY_TIMEOUT) {
                Object error = SoulResultWrap.error(SoulResultEnum.SERVICE_TIMEOUT.getCode(), SoulResultEnum.SERVICE_TIMEOUT.getMsg(), null);
                return WebFluxResultUtils.result(exchange, error);
            }
            response.setStatusCode(clientResponse.statusCode());
            response.getCookies().putAll(clientResponse.cookies());
            response.getHeaders().putAll(clientResponse.headers().asHttpHeaders());
            // 返回结果
            return response.writeWith(clientResponse.body(BodyExtractors.toDataBuffers()));
        }));
    }