explain-unicloud/program/run.js

uniCloud云函数框架

"use strict";

const middleware = require("./middleware");

module.exports = async ({
	event,
	context,
	startup
}) => {
	// 构建explain对象
	let explain = {
		// 模式：路由模式 route/匹配模式 match
		mode: "",
		// 基础配置
		config: {},
		// 请求
		request: {
			service: "", // 匹配到的service
			action: "", // 匹配到的action
			data: {}, // 客户端传入的参数
			isHttp: false, // 是否是HTTP请求
			route: undefined, // 客户端传入的路由，只有当mode为route时该属性才有值
			routeTemplate: undefined, // 成功匹配的路由模板，只有当mode为route时该属性才有值
			httpMethod: undefined // HTTP Method，只有当mode为route时该属性才有值
		},
		// 响应
		response: {
			mpserverlessComposedResponse: true, // 使用阿里云返回集成响应是需要此字段为true
			statusCode: 200,
			headers: {
				"content-type": event.headers && event.headers["content-type"] || "application/json" // 默认响应json格式数据
			},
			body: undefined
		},
		// 异常
		exception: undefined,
		// 路由
		routes: [],
		// 中间件
		middlewares: [],
		// 过滤器
		filters: [],
		/**
		 * 扩展方法，在服务中引入并使用其他服务
		 */
		useService: obj => {
			return new obj({
				event,
				context,
				explain
			});
		}
	}

	// 应用属性
	let app = {
		/**
		 * 初始化
		 */
		init: ({
			baseDir = "",
			serviceDir = "/services/",
			serviceKey = "service",
			actionKey = "action",
			dataKey = "data",
			enableMatchMode = true,
			matchIgnore = []
		}) => {
			explain.config.baseDir = baseDir;
			explain.config.serviceDir = serviceDir;
			explain.config.serviceKey = serviceKey;
			explain.config.actionKey = actionKey;
			explain.config.dataKey = dataKey;
			explain.config.enableMatchMode = enableMatchMode;
			explain.config.matchIgnore = matchIgnore;
		},
		/**
		 * 添加中间件
		 */
		use: middleware => {
			explain.middlewares.push(middleware);
		},
		route: {
			/**
			 * 路由添加
			 */
			add: routes => {
				if (routes.constructor === Array) {
					explain.routes = explain.routes.concat(routes);
				} else if (routes.constructor === Object) {
					explain.routes.push(routes);
				}
			}
		},
		filter: {
			/**
			 * 过滤器添加
			 */
			add: filters => {
				if (filters.constructor === Array) {
					explain.filters = explain.filters.concat(filters);
				} else if (filters.constructor === Object) {
					explain.filters.push(filters);
				}
			}
		}
	}

	if (startup) {
		startup(app);
	}

	if (!explain.config.baseDir) {
		throw new Error(`"baseDir"必须配置。`);
	}

	// 使用中间件
	await middleware.use({
		event,
		context,
		explain
	});

	// console.log(explain.mode);
	// console.log(explain.response);
	if (explain.mode === "route") {
		// return explain.response 之前可以正常响应，现在会报错 The Body of Composed Response is not valid
		// 不知道是不是服务商更新后出现的bug，解决办法为JSON对象转为JSON字符串再传入body即可
		explain.response.body =
			typeof explain.response.body === "string" ?
			explain.response.body :
			JSON.stringify(explain.response.body); // route模式需要集成响应，集成响应body需要转为字符串
		return explain.response;
	} else if (explain.mode === "match") {
		return explain.response.body; // match模式不需要集成响应
	}
}