4.2.6 框架之网络请求-拦截器

在整个http的链路中，异常错误对前端来说尤为重要，他作用在很多不同的场景，通用的比如500, 502等; 一个好的软件通常需要在不同的错误场景中做不同的事情。当用户cookie失效时，希望能自动跳转到登录页；当用户权限发生变更时，希望能跳转到一个友好的提示页；那么如何满足这些个性化的诉求呢？接下来让我们一起了解oinone前端网络请求-拦截器。

一、入口

在src目录下main.ts中可以看到VueOioProvider，这是系统功能提供者的注册入口

import interceptor from './middleware/network-interceptor';
VueOioProvider(
  {
    http: {
      callback: interceptor
    }
  },
  []
);

二、middleware

在项目初始化时使用CLI构建初始化前端工程，在src/middleware有拦截器的默认实现：

三、interceptor

interceptor在请求返回后触发，interceptor有两个回调函数，error和next

error参数

• graphQLErrors 处理业务异常

• networkError 处理网络异常

next

• extensions 后端返回扩展参数

const interceptor: RequestHandler = (operation, forward) => {
  return forward(operation).subscribe({
    error: ({ graphQLErrors, networkError }) => {
            console.log(graphQLErrors, networkError);
      // 默认实现 => interceptor error 
    },
    next: ({ extensions }) => {
            console.log(extensions);
      // 默认实现 => interceptor next 
    },
  });
};

四、interceptor error

// 定义错误提示等级
const DEFAULT_MESSAGE_LEVEL = ILevel.ERROR;
// 错误提示等级 对应提示的报错
const MESSAGE_LEVEL_MAP = {
  [ILevel.ERROR]: [ILevel.ERROR],
  [ILevel.WARN]: [ILevel.ERROR, ILevel.WARN],
  [ILevel.INFO]: [ILevel.ERROR, ILevel.WARN, ILevel.INFO],
  [ILevel.SUCCESS]: [ILevel.ERROR, ILevel.WARN, ILevel.INFO, ILevel.SUCCESS],
  [ILevel.DEBUG]: [ILevel.ERROR, ILevel.WARN, ILevel.INFO, ILevel.SUCCESS, ILevel.DEBUG]
};
// 错误提示通用函数
const notificationMsg = (type: string = 'error', tip: string = '错误', desc: string = '') => {
  notification[type]({
    message: tip,
    description: desc
  });
};
// 根据错误等级 返回错误提示和类型
const getMsgInfoByLevel = (level: ILevel) => {
  let notificationType = 'info';
  let notificationText = translate('kunlun.common.info');
  switch (level) {
    case ILevel.DEBUG:
      notificationType = 'info';
      notificationText = translate('kunlun.common.debug');
      break;
    case ILevel.INFO:
      notificationType = 'info';
      notificationText = translate('kunlun.common.info');
      break;
    case ILevel.SUCCESS:
      notificationType = 'success';
      notificationText = translate('kunlun.common.success');
      break;
    case ILevel.WARN:
      notificationType = 'warning';
      notificationText = translate('kunlun.common.warning');
      break;
  }
  return {
    notificationType,
    notificationText
  };
};

error: ({ graphQLErrors, networkError }) => {
      if (graphQLErrors) {
        graphQLErrors.forEach(async ({ message, locations, path, extensions }) => {
          let { errorCode, errorMessage, messages } = extensions || {};
          // FIXME: extensions.errorCode
          if (errorCode == null) {
            const codeArr = /code: (\d+),/.exec(message);
            if (codeArr) {
              errorCode = Number(codeArr[1]);
            }
          }
          if (errorMessage == null) {
            const messageArr = /msg: (.*),/.exec(message);
            if (messageArr) {
              errorMessage = messageArr[1];
            }
          }
          // 错误通用提示
          if (messages && messages.length) {
            messages.forEach((m) => {
              notificationMsg('error', translate('kunlun.common.error'), m.message || '');
            });
          } else {
            notificationMsg('error', translate('kunlun.common.error'), errorMessage || message);
          }
            // 提示扩展信息 根据错误等级来提示对应级别的报错
          const extMessage = getValue(response, 'extensions.messages');
          if (extMessage && extMessage.length) {
            const messageLevelArr = MESSAGE_LEVEL_MAP[DEFAULT_MESSAGE_LEVEL];
            extMessage.forEach((m) => {
              if (messageLevelArr.includes(m.level)) {
                const { notificationType, notificationText } = getMsgInfoByLevel(m.level);
                notificationMsg(notificationType, notificationText, m.message || '');
              }
            });
          }

          // 消息模块的用户未登录错误码
          const MAIL_USER_NOT_LOGIN = 20080002;
          // 基础模块的用户未登录错误码
          const BASE_USER_NOT_LOGIN_ERROR = 11500001;
          if (
            [MAIL_USER_NOT_LOGIN, BASE_USER_NOT_LOGIN_ERROR].includes(Number(errorCode)) &&
            location.pathname !== '/auth/login'
          ) {
            const redirect_url = location.pathname;
            location.href = `/login?redirect_url=${redirect_url}`;
          }
          /**
           * 应用配置异常跳转至通用的教程页面
           */
          // 模块参数配置未完成
          const BASE_SYSTEM_CONFIG_IS_NOT_COMPLETED_ERROR = 11500004;
          if ([BASE_SYSTEM_CONFIG_IS_NOT_COMPLETED_ERROR].includes(Number(errorCode))) {
            const action = getValue(response, 'extensions.extra.action');
            if (action) {
              Action.registerAction(action.model, action);
              const searchParams: string[] = [];
              searchParams.push(`module=${action.module}`);
              searchParams.push(`model=${action.model}`);
              searchParams.push(`viewType=${action.viewType}`);
              searchParams.push(`actionId=${action.id}`);
              const href = `${origin}/page;${searchParams.join(';')}`;
              location.href = href;
            }
          }
        });
      }
      if (networkError) {
        const { name, result } = networkError;
        const errMsg = (result && result.message) || `${networkError}`;
        if (name && result && result.message) {
          notification.error({
            message: translate('kunlun.common.error'),
            description: `[${name}]: ${errMsg}`,
          });
        }
      }
    }

四、interceptor next

next: ({ extensions }) => {
  if (extensions) {
    const messages = extensions.messages as {
      level: 'SUCCESS';
      message: string;
    }[];
    if (messages)
      messages.forEach((msg) => {
        notification.success({
          message: '操作成功',
          description: msg.message,
        });
      });
  }
}

六、完整代码

import { NextLink, Operation } from 'apollo-link';
import { notification } from 'ant-design-vue';
import getValue from 'lodash/get';
import { Action, ILevel, translate } from '@kunlun/dependencies';

interface RequestHandler {
  (operation: Operation, forward: NextLink): Promise<any> | any;
}

const DEFAULT_MESSAGE_LEVEL = ILevel.ERROR;
const MESSAGE_LEVEL_MAP = {
  [ILevel.ERROR]: [ILevel.ERROR],
  [ILevel.WARN]: [ILevel.ERROR, ILevel.WARN],
  [ILevel.INFO]: [ILevel.ERROR, ILevel.WARN, ILevel.INFO],
  [ILevel.SUCCESS]: [ILevel.ERROR, ILevel.WARN, ILevel.INFO, ILevel.SUCCESS],
  [ILevel.DEBUG]: [ILevel.ERROR, ILevel.WARN, ILevel.INFO, ILevel.SUCCESS, ILevel.DEBUG]
};

const notificationMsg = (type: string = 'error', tip: string = '错误', desc: string = '') => {
  notification[type]({
    message: tip,
    description: desc
  });
};

const getMsgInfoByLevel = (level: ILevel) => {
  let notificationType = 'info';
  let notificationText = translate('kunlun.common.info');
  switch (level) {
    case ILevel.DEBUG:
      notificationType = 'info';
      notificationText = translate('kunlun.common.debug');
      break;
    case ILevel.INFO:
      notificationType = 'info';
      notificationText = translate('kunlun.common.info');
      break;
    case ILevel.SUCCESS:
      notificationType = 'success';
      notificationText = translate('kunlun.common.success');
      break;
    case ILevel.WARN:
      notificationType = 'warning';
      notificationText = translate('kunlun.common.warning');
      break;
  }
  return {
    notificationType,
    notificationText
  };
};

const interceptor: RequestHandler = (operation, forward) => {
  return forward(operation).subscribe({
    error: ({ graphQLErrors, networkError, response }) => {
      if (graphQLErrors) {
        graphQLErrors.forEach(async ({ message, locations, path, extensions }) => {
          let { errorCode, errorMessage, messages } = extensions || {};
          // FIXME: extensions.errorCode
          if (errorCode == null) {
            const codeArr = /code: (\d+),/.exec(message);
            if (codeArr) {
              errorCode = Number(codeArr[1]);
            }
          }
          if (errorMessage == null) {
            const messageArr = /msg: (.*),/.exec(message);
            if (messageArr) {
              errorMessage = messageArr[1];
            }
          }
          if (messages && messages.length) {
            messages.forEach((m) => {
              notificationMsg('error', translate('kunlun.common.error') || '', m.message || '');
            });
          } else {
            notificationMsg('error', translate('kunlun.common.error') || '', errorMessage || message);
          }

          const extMessage = getValue(response, 'extensions.messages');
          if (extMessage && extMessage.length) {
            const messageLevelArr = MESSAGE_LEVEL_MAP[DEFAULT_MESSAGE_LEVEL];
            extMessage.forEach((m) => {
              if (messageLevelArr.includes(m.level)) {
                const { notificationType, notificationText } = getMsgInfoByLevel(m.level);
                notificationMsg(notificationType, notificationText, m.message || '');
              }
            });
          }
          console.log(extMessage);

          // 消息模块的用户未登录错误码
          const MAIL_USER_NOT_LOGIN = 20080002;
          // 基础模块的用户未登录错误码
          const BASE_USER_NOT_LOGIN_ERROR = 11500001;
          if (
            [MAIL_USER_NOT_LOGIN, BASE_USER_NOT_LOGIN_ERROR].includes(Number(errorCode)) &&
            location.pathname !== '/auth/login'
          ) {
            const redirect_url = location.pathname;
            location.href = `/login?redirect_url=${redirect_url}`;
          }
          /**
           * 应用配置异常跳转至通用的教程页面
           */
          // 模块参数配置未完成
          const BASE_SYSTEM_CONFIG_IS_NOT_COMPLETED_ERROR = 11500004;
          if ([BASE_SYSTEM_CONFIG_IS_NOT_COMPLETED_ERROR].includes(Number(errorCode))) {
            const action = getValue(response, 'extensions.extra.action');
            if (action) {
              Action.registerAction(action.model, action);
              const searchParams: string[] = [];
              searchParams.push(`module=${action.module}`);
              searchParams.push(`model=${action.model}`);
              searchParams.push(`viewType=${action.viewType}`);
              searchParams.push(`actionId=${action.id}`);
              const href = `${origin}/page;${searchParams.join(';')}`;
              location.href = href;
            }
          }
        });
      }
      if (networkError) {
        const { name, result } = networkError;
        const errMsg = (result && result.message) || `${networkError}`;
        if (name && result && result.message) {
          notification.error({
            message: translate('kunlun.common.error') || '',
            description: `[${name}]: ${errMsg}`
          });
        }
      }
    }
  });
};

export default interceptor;