初次提交

src/error.ts

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+export class RouterError extends Error {
+	#code: string;
+
+	public constructor(code: string, message: string) {
+		super(message);
+		this.#code = code;
+	}
+
+	public get code(): string {
+		return this.#code;
+	}
+}

src/index.ts

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+export * from "./error";
+export * from "./router";

src/router.ts

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+import { Middleware } from "koa";
+import Koa from "koa";
+import { RouterError } from "./error";
+
+
+
+export type KoaRouterMethods = "get" | "post" | "put" | "delete" | "patch";
+
+interface IKoaRouterMatcher {
+}
+
+interface IKoaRouteConfig {
+	method: KoaRouterMethods
+	pathname: string
+	regexp: RegExp
+	parsers: Record<string, IKoaRouterTypeParser>
+	middleware: Middleware
+}
+
+interface IKoaRouterTypeParser {
+	(value: string): any
+}
+
+type KoaRouterDefaultTypes = "int" | "boolean";
+
+export interface IKoaRouterOptions {
+	/** 前缀 */
+	prefix?: string;
+	/** 默认的参数类型，如果传true则安装所有，如果传数组则安装指定的类型 */
+	defaultParamTypes?: Array<KoaRouterDefaultTypes> | boolean;
+	/** 自定义类型 */
+	customParamtypes?: Record<string, { regexp: RegExp, parser?: IKoaRouterTypeParser }>
+}
+
+export class KoaRouter {
+
+	#option: IKoaRouterOptions
+	#types: Record<string, { regexpString: string, parser?: IKoaRouterTypeParser }> = {};
+	#routes: IKoaRouteConfig[] = [];
+
+	constructor(option?: IKoaRouterOptions) {
+		this.#option = {
+			...option,
+			prefix: option?.prefix?.replace(/\/+$/, "") ?? "/",
+		};
+
+		//参数类型安装
+		if (typeof option?.defaultParamTypes === "boolean") {
+			if (option.defaultParamTypes) this.installDefaultParamTypes();
+		}
+		else if (Array.isArray(option?.defaultParamTypes)) this.installDefaultParamTypes(option.defaultParamTypes);
+
+		//自定义类型安装
+		if (option?.customParamtypes) {
+			for (const key in option.customParamtypes) {
+				this.installParamType(key, option.customParamtypes[key].regexp, option.customParamtypes[key].parser);
+			}
+		}
+	}
+
+	/**
+	 * 安装类型，类型安装后，可以在路由路径中使用类型参数，例如：
+	 * 
+	 * 	"/users/{id:int}"
+	 * 
+	 * 	"/users/{name:string}"
+	 * 
+	 * @param typename 类型名称
+	 * @param regexp 类型正则表达式（不能包含开始符号^和结束符号$）
+	 * @param parser 匹配结果转换函数
+	 */
+	public installParamType(typename: string, regexp: RegExp, parser?: IKoaRouterTypeParser) {
+		this.#types[typename] = { regexpString: regexp.toString().slice(1, -1), parser };
+	}
+
+	/**
+	 * 安装默认类型
+	 * @param types 要安装的类型，如果没有传递则安装所有类型
+	 */
+	public installDefaultParamTypes(types?: KoaRouterDefaultTypes[]) {
+		const typeMap: Record<KoaRouterDefaultTypes, { regexp: RegExp, parser?: IKoaRouterTypeParser }> = {
+			"int": { regexp: /\d+/, parser: parseInt },
+			"boolean": { regexp: /(true|false|yes|no|on|off)/, parser: (v: string) => v.toLowerCase() == "true" },
+		};
+		for (const type of types ?? Object.keys(typeMap)) {
+			if (typeMap[type as KoaRouterDefaultTypes]) this.installParamType(type, typeMap[type as KoaRouterDefaultTypes].regexp, typeMap[type as KoaRouterDefaultTypes].parser);
+		}
+	}
+
+	/**
+	 * 注册路由
+	 * @param method 路由方法
+	 * @param pathname 路由路径
+	 * @param middleware 路由中间件
+	 */
+	public register(method: KoaRouterMethods[], pathname: string, middleware: Middleware): void {
+		//处理路径参数
+		const prefix = this.#option.prefix?.replace(/\/+$/, "") ?? "";
+		pathname = prefix + (pathname[0] == "/" ? pathname : `/${pathname}`);
+
+		//匹配参数
+		// 支持的参数格式有:
+		// 		{name}
+		// 		{name:type}
+		const res = pathname.matchAll(/\{([a-zA-Z][a-zA-Z0-9_]*)(:([a-zA-Z][a-zA-Z0-9_]*))?\}/g);
+		const parsers: IKoaRouteConfig["parsers"] = {};
+
+		//处理参数，并生成正则表达式
+		const regexpItems: string[] = [];
+		let offset = 0;
+		for (const match of res) {
+			const name = match[1];
+			const type = match[3];
+			//放入路由前部分
+			regexpItems.push(pathname.slice(offset, match.index));
+
+			//放入路由参数部分
+			if (type) {
+				if (!this.#types[type]) throw new RouterError("ERR_ROUTER_PARAM_TYPE_NOT_INSTALL", `路由参数类型"${type}"未安装`);
+				regexpItems.push(`(?<${name}>${this.#types[type].regexpString})`)
+				if (this.#types[type].parser) parsers[name] = this.#types[type].parser;
+			}
+			else regexpItems.push(`(?<${name}>[^/]+)`);
+
+			//剩余内容
+			offset = match.index + match[0].length;
+		}
+
+		//得到正则表达式
+		const regexpStr = "^" + regexpItems.join("") + pathname.slice(offset) + "$";
+		const regexp = new RegExp(regexpStr);
+
+		//注册路由
+		for (const m of method) this.#routes.push({ method: m, pathname, regexp, middleware, parsers });
+	}
+
+	/**
+	 * 注册GET路由
+	 * @param pathname 路由路径
+	 * @param middleware 路由中间件
+	 */
+	public get(pathname: string, middleware: Middleware) { this.register(["get"], pathname, middleware); }
+
+	/**
+	 * 注册POST路由
+	 * @param pathname 路由路径
+	 * @param middleware 路由中间件
+	 */
+	public post(pathname: string, middleware: Middleware) { this.register(["post"], pathname, middleware); }
+
+	/**
+	 * 注册PUT路由
+	 * @param pathname 路由路径
+	 * @param middleware 路由中间件
+	 */
+	public put(pathname: string, middleware: Middleware) { this.register(["put"], pathname, middleware); }
+
+	/**
+	 * 注册DELETE路由
+	 * @param pathname 路由路径
+	 * @param middleware 路由中间件
+	 */
+	public delete(pathname: string, middleware: Middleware) { this.register(["delete"], pathname, middleware); }
+
+	/**
+	 * 注册PATCH路由
+	 * @param pathname 路由路径
+	 * @param middleware 路由中间件
+	 */
+	public patch(pathname: string, middleware: Middleware) { this.register(["patch"], pathname, middleware); }
+
+	/**
+	 * 注册所有路由方法
+	 * @param pathname 路由路径
+	 * @param middleware 路由中间件
+	 */
+	public all(pathname: string, middleware: Middleware) { this.register(["get", "post", "put", "delete", "patch"], pathname, middleware); }
+
+	/** 路由匹配中间件 */
+	public callback(): Middleware {
+		return (ctx: Koa.Context, next: Koa.Next) => {
+			//匹配路由
+			const method = ctx.method.toLocaleLowerCase() as KoaRouterMethods;
+			let match: RegExpMatchArray | null = null as any;
+			const route = this.#routes.find(route => {
+				if (route.method != method) return false;
+				match = ctx.URL.pathname.match(route.regexp);
+				return match != null;
+			})
+			if (!route) return next();
+
+			//处理参数
+			const params = match?.groups ?? {};
+			for (const key in route.parsers) {
+				params[key] = route.parsers[key](params[key]);
+			}
+			ctx.params = params;
+
+			//执行中间件
+			return route.middleware(ctx, next);
+		}
+	}
+
+	get #prefix() {
+		return this.#option.prefix!;
+	}
+
+}
+
+
+