implement #5

Author: eviltik

index.js

@@ -16,6 +16,7 @@ class UdgerParser {
      */
     constructor(file) {
         this.db = new Database(file, {readonly: true, fileMustExist: true});
+        this.file = file;
         this.ip = null;
         this.ua = null;
 
@@ -29,6 +30,32 @@ class UdgerParser {
         this.retIp = {};
     }
 
+    /**
+     * Connect (reconnect) sqlite database
+     * @return {Boolean} true if db has been opened, false if already connected
+     */
+    connect() {
+        if (!this.db) {
+            this.db = new Database(this.file, {readonly: true, fileMustExist: true});
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Disconnect sqlite database, avoid read/write conflict
+     * see https://github.com/udger/udger-updater-nodejs/issues/5
+     * @return {Boolean} true if db has been closed, false if no db opened
+     */
+    disconnect() {
+        if (this.db) {
+            this.db.close();
+            this.db = null;
+            return true;
+        }
+        return false;
+    }
+
     /**
      * Initialize User-Agent or IP(v4/v6), or both
      * @param {Object} data - An object
@@ -149,6 +176,13 @@ class UdgerParser {
         }
     }
 
+    /**
+     * Clean the cache
+     */
+    cacheClean() {
+        this.cache = {};
+    }
+
     /**
      * Parse the User-Agent string
      * @param {String} ua - An User-Agent string
@@ -813,6 +847,8 @@ class UdgerParser {
      */
     parse(opts) {
 
+        if (!this.db) return {};
+
         if (
             this.isCacheEnable() &&
             this.cacheKeyExist(this.keyCache)

test/dbConnect.js

@@ -0,0 +1,60 @@
+const tap = require('tap');
+const config = require('./lib/config');
+
+tap.test(
+    'Connect: disconnect() should return true',
+    (t) => {
+        let disconnected = config.udgerParser.disconnect();
+        t.same(disconnected, true);
+        t.end();
+    }
+);
+
+tap.test(
+    'Connect: disconnect() should return false (already disconnected)',
+    (t) => {
+        let disconnected = config.udgerParser.disconnect();
+        t.same(disconnected, false);
+        t.end();
+    }
+);
+
+tap.test(
+    'Connect: parse() should return {} because disconnected',
+    (t) => {
+        let ret = config.udgerParser.parse();
+        t.same(ret, {});
+        t.end();
+    }
+);
+
+tap.test(
+    'Connect: connect() should return true',
+    (t) => {
+        let reconnected = config.udgerParser.connect();
+        t.same(reconnected, true);
+        t.end();
+    }
+);
+
+tap.test(
+    'Connect: connect() should return false (already connected)',
+    (t) => {
+        let reconnected = config.udgerParser.connect();
+        t.same(reconnected, false);
+        t.end();
+    }
+);
+
+tap.test(
+    'Connect: parse() should return an object',
+    (t) => {
+        let ret = config.udgerParser.parse();
+        t.same(ret, {
+            from_cache:false,
+            ip_address:{},
+            user_agent:{}
+        });
+        t.end();
+    }
+);