精简缓存逻辑，精简文档 (#915)

https://github.com/HenryQW/RSSHub/issues/6
https://github.com/HenryQW/RSSHub/issues/7

docs/README.md

@@ -1494,15 +1494,13 @@ IATA 国际航空运输协会机场代码, 参见[维基百科 国际航空运
 
 ### 中国美术馆
 
-<route name="通知公告" author="HenryQW" example="/namoc/announcement" path="/namoc/announcement"/>
+<route name="美术馆新闻" author="HenryQW" example="/namoc/announcement" path="/namoc/:type" :paramsDesc="['新闻类型， 可选如下']">
 
-<route name="新闻" author="HenryQW" example="/namoc/news" path="/namoc/news"/>
+| 通知公告     | 新闻 | 媒体联报 | 展览预告   | 焦点专题 |
+| ------------ | ---- | -------- | ---------- | -------- |
+| announcement | news | media    | exhibition | specials |
 
-<route name="媒体联报" author="HenryQW" example="/namoc/media" path="/namoc/media"/>
-
-<route name="展览预告" author="HenryQW" example="/namoc/exhibition" path="/namoc/exhibition"/>
-
-<route name="焦点专题" author="HenryQW" example="/namoc/specials" path="/namoc/specials"/>
+</route>
 
 ### 国家地理
 

middleware/cache-common.js

@@ -0,0 +1,65 @@
+const pathToRegExp = require('path-to-regexp');
+const readall = require('readall');
+const crypto = require('crypto');
+
+const paired = (route, path) => {
+    const options = {
+        sensitive: true,
+        strict: true,
+    };
+
+    return pathToRegExp(route, [], options).exec(path);
+};
+
+// eslint-disable-next-line no-unused-vars
+const read = (stream) =>
+    new Promise((resolve, reject) => {
+        readall(stream, (err, data) => {
+            if (err) {
+                reject(err);
+            } else {
+                resolve(data);
+            }
+        });
+    });
+
+const md5 = (str) =>
+    crypto
+        .createHash('md5')
+        .update(str)
+        .digest('hex');
+
+const validityCheck = (routes, exclude, path) => {
+    let match = false;
+    let routeExpire = false;
+
+    for (let i = 0; i < routes.length; i++) {
+        let route = routes[i];
+
+        if (typeof routes[i] === 'object') {
+            route = routes[i].path;
+            routeExpire = routes[i].expire;
+        }
+
+        if (paired(route, path)) {
+            match = true;
+            break;
+        }
+    }
+
+    for (let j = 0; j < exclude.length; j++) {
+        if (paired(exclude[j], path)) {
+            match = false;
+            break;
+        }
+    }
+
+    return { match, routeExpire };
+};
+
+module.exports = {
+    paired,
+    read,
+    md5,
+    validityCheck,
+};

middleware/lru-cache.js

@@ -1,9 +1,7 @@
-// baed on https://github.com/coderhaoxin/koa-redis-cache
+// based on https://github.com/coderhaoxin/koa-redis-cache
 
-const pathToRegExp = require('path-to-regexp');
-const readall = require('readall');
-const crypto = require('crypto');
 const lru = require('lru-cache');
+const common = require('./cache-common');
 
 module.exports = function(options = {}) {
     const {
@@ -29,31 +27,10 @@ module.exports = function(options = {}) {
     return async function cache(ctx, next) {
         const { url, path } = ctx.request;
         const resolvedPrefix = typeof prefix === 'function' ? prefix.call(ctx, ctx) : prefix;
-        const key = resolvedPrefix + md5(ignoreQuery ? path : url);
+        const key = resolvedPrefix + common.md5(ignoreQuery ? path : url);
         const tkey = key + ':type';
-        let match = false;
-        let routeExpire = false;
 
-        for (let i = 0; i < routes.length; i++) {
-            let route = routes[i];
-
-            if (typeof routes[i] === 'object') {
-                route = routes[i].path;
-                routeExpire = routes[i].expire;
-            }
-
-            if (paired(route, path)) {
-                match = true;
-                break;
-            }
-        }
-
-        for (let j = 0; j < exclude.length; j++) {
-            if (paired(exclude[j], path)) {
-                match = false;
-                break;
-            }
-        }
+        let { match, routeExpire } = common.validityCheck(routes, exclude, path);
 
         if (!match || (passParam && ctx.request.query[passParam])) {
             return await next();
@@ -134,32 +111,3 @@ module.exports = function(options = {}) {
         }
     }
 };
-
-function paired(route, path) {
-    const options = {
-        sensitive: true,
-        strict: true,
-    };
-
-    return pathToRegExp(route, [], options).exec(path);
-}
-
-// eslint-disable-next-line no-unused-vars
-function read(stream) {
-    return new Promise((resolve, reject) => {
-        readall(stream, (err, data) => {
-            if (err) {
-                reject(err);
-            } else {
-                resolve(data);
-            }
-        });
-    });
-}
-
-function md5(str) {
-    return crypto
-        .createHash('md5')
-        .update(str)
-        .digest('hex');
-}

middleware/redis-cache.js

@@ -1,10 +1,8 @@
-// baed on https://github.com/coderhaoxin/koa-redis-cache
+// based on https://github.com/coderhaoxin/koa-redis-cache
 
-const pathToRegExp = require('path-to-regexp');
 const wrapper = require('co-redis');
-const readall = require('readall');
-const crypto = require('crypto');
 const Redis = require('redis');
+const common = require('./cache-common');
 
 module.exports = function(options = {}) {
     let redisAvailable = false;
@@ -50,31 +48,10 @@ module.exports = function(options = {}) {
     return async function cache(ctx, next) {
         const { url, path } = ctx.request;
         const resolvedPrefix = typeof prefix === 'function' ? prefix.call(ctx, ctx) : prefix;
-        const key = resolvedPrefix + md5(ignoreQuery ? path : url);
+        const key = resolvedPrefix + common.md5(ignoreQuery ? path : url);
         const tkey = key + ':type';
-        let match = false;
-        let routeExpire = false;
 
-        for (let i = 0; i < routes.length; i++) {
-            let route = routes[i];
-
-            if (typeof routes[i] === 'object') {
-                route = routes[i].path;
-                routeExpire = routes[i].expire;
-            }
-
-            if (paired(route, path)) {
-                match = true;
-                break;
-            }
-        }
-
-        for (let j = 0; j < exclude.length; j++) {
-            if (paired(exclude[j], path)) {
-                match = false;
-                break;
-            }
-        }
+        let { match, routeExpire } = common.validityCheck(routes, exclude, path);
 
         if (!redisAvailable || !match || (passParam && ctx.request.query[passParam])) {
             return await next();
@@ -155,32 +132,3 @@ module.exports = function(options = {}) {
         }
     }
 };
-
-function paired(route, path) {
-    const options = {
-        sensitive: true,
-        strict: true,
-    };
-
-    return pathToRegExp(route, [], options).exec(path);
-}
-
-// eslint-disable-next-line no-unused-vars
-function read(stream) {
-    return new Promise((resolve, reject) => {
-        readall(stream, (err, data) => {
-            if (err) {
-                reject(err);
-            } else {
-                resolve(data);
-            }
-        });
-    });
-}
-
-function md5(str) {
-    return crypto
-        .createHash('md5')
-        .update(str)
-        .digest('hex');
-}