广州-肖业翔-同步锁，忽略超时重试

.gitignore

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+node_modules

index.js

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+const Koa = require('koa');
+const Router = require('koa-router');
+const redisCli = require('./util/client');
+const db = require('./util/db');
+
+const app = new Koa();
+const router = new Router();
+
+const PORT = 3000;
+const CACHE_KEY = 'cache-top5';
+
+router.get('/', async (ctx, next) => {
+    await next();
+    redisCli.set('testcli', '我只是想看看封装的能不能用着了', 'EX', 3600);
+    ctx.body = `It's OK! ${PORT}`
+});
+
+router.get('/cache', async (ctx, next) => {
+    await next();
+
+    let top5 = await redisCli.get(CACHE_KEY);
+    if(!top5) {
+        top5 = await db.query('select * from websites limit 5');
+        console.log('get db: ', top5.length);
+        if(await redisCli.checkLock(CACHE_KEY)) {
+            ctx.body = top5;
+        }
+        try {
+            await redisCli.set(CACHE_KEY, JSON.stringify(top5), 'PX', 360000);
+        } catch (err) {
+            console.log(`redisCli set err: ${err}`);
+            ctx.body = top5;
+        }
+    }
+
+    console.log('get cache: ', top5.length);
+    ctx.body = top5;
+});
+
+app.use(router.routes()).use(router.allowedMethods());
+
+app.listen(PORT, () => {
+    console.log(`listening http://localhost:${PORT}`);
+});