node-cache · erdii · Jul 26, 2019 · Jul 24, 2019 · Jul 25, 2019
diff --git a/README.md b/README.md
@@ -329,6 +329,29 @@ console.log( mykeys );
 
 ```
 
+## Has key (HAS)
+
+`myCache.has( key, [callback] )`
+
+Returns boolean indicating if the key is cached.
+
+```js
+// async
+myCache.has( 'myKey',  function( err, exists ){
+  if( !err ){
+    console.log( exists );
+   // true
+  }
+});
+
+// sync
+exists = myCache.has( 'myKey' );
+
+console.log( exists );
+// true
+
+```
+
 ## Statistics (STATS):
 
 `myCache.getStats()`

diff --git a/_src/lib/node_cache.coffee b/_src/lib/node_cache.coffee
@@ -104,7 +104,6 @@ module.exports = class NodeCache extends EventEmitter
 				cb( null, undefined ) if cb?
 			return undefined
 
-
 	# ## mget
 	#
 	# get multiple cached keys at once and change the stats
@@ -393,6 +392,30 @@ module.exports = class NodeCache extends EventEmitter
 		cb( null, _keys )if cb?
 		return _keys
 
+	# ## has
+	#
+	# Check if a key is cached
+	#
+	# **Parameters:**
+	#
+	# * `key` ( String | Number ): cache key to check the ttl value
+	# * `[cb]` ( Function ): Callback function
+	#
+	# **Return**
+	#
+	# ( Boolean ): A boolean that indicates if the key is cached
+	#
+	# **Example:**
+	#
+	#     _exists = myCache.has('myKey')
+	#
+	#     # true
+	#
+	has: ( key, cb )=>
+		_exists = @data[ key ]? and @_check( key, @data[ key ] )
+		cb( null, _exists )if cb?
+		return _exists
+
 	# ## getStats
 	#
 	# get the stats

diff --git a/_src/test/mocha_test.coffee b/_src/test/mocha_test.coffee
@@ -76,6 +76,20 @@ describe "`#{pkg.name}@#{pkg.version}` on `node@#{process.version}`", () ->
 				done()
 			return
 
+		it "has a key", (done) ->
+			localCache.has state.key, (err, res) ->
+				should.not.exist err
+				res.should.eql true
+				done()
+			return
+
+		it "doesn not have a key", (done) ->
+			localCache.has 'non existing key', (err, res) ->
+				should.not.exist err
+				res.should.eql false
+				done()
+			return
+
 		it "get key names", (done) ->
 			localCache.keys (err, res) ->
 				state.n++
@@ -253,6 +267,16 @@ describe "`#{pkg.name}@#{pkg.version}` on `node@#{process.version}`", () ->
 			[state.key].should.eql res
 			return
 
+		it "has key", () ->
+			res = localCache.has(state.key)
+			res.should.eql true
+			return
+
+		it "does not have key", () ->
+			res = localCache.has('non existing key')
+			res.should.eql false
+			return
+
 		it "delete an undefined key", () ->
 			count = localCache.del "xxx"
 			0.should.eql count
@@ -1148,9 +1172,52 @@ describe "`#{pkg.name}@#{pkg.version}` on `node@#{process.version}`", () ->
 				key3: "k3_#{randomString 20}"
 				key4: "k4_#{randomString 20}"
 				key5: "k5_#{randomString 20}"
+				key6: "k6_#{randomString 20}"
 				now: Date.now()
 			state.keys = [state.key1, state.key2, state.key3, state.key4, state.key5]
 			return
+
+		describe "has validates expired ttl", () -> 
+			it "set a key with ttl", () ->
+				localCacheTTL.set state.key6, state.val, 0.7, (err, res) ->
+					should.not.exist err
+					true.should.eql res
+				return
+
+			it "check this key immediately", () ->
+				localCacheTTL.has state.key6, (err, res) ->
+					should.not.exist err
+					res.should.eql true
+					return
+				return
+
+			it "before it times out", (done) ->
+				setTimeout(() ->
+					state.n++
+					res = localCacheTTL.has state.key6
+					res.should.eql true
+					localCacheTTL.get state.key6, (err, res) ->
+						should.not.exist err
+						state.val.should.eql res
+						done()
+						return
+				, 20)
+				return
+
+			it "and after it timed out", (done) ->
+				setTimeout(() ->
+					res = localCacheTTL.has state.key6
+					res.should.eql false
+
+					state.n++
+					localCacheTTL.get state.key6, (err, res) ->
+						should.not.exist err
+						should(res).be.undefined()
+						done()
+						return
+					return
+				, 800)
+				return
 
 		it "set a key with ttl", () ->
 			localCache.set state.key1, state.val, 0.7, (err, res) ->
@@ -1172,6 +1239,8 @@ describe "`#{pkg.name}@#{pkg.version}` on `node@#{process.version}`", () ->
 		it "before it times out", (done) ->
 			setTimeout(() ->
 				state.n++
+				res = localCache.has state.key1
+				res.should.eql true
 				localCache.get state.key1, (err, res) ->
 					should.not.exist err
 					state.val.should.eql res
@@ -1182,6 +1251,9 @@ describe "`#{pkg.name}@#{pkg.version}` on `node@#{process.version}`", () ->
 
 		it "and after it timed out", (done) ->
 			setTimeout(() ->
+				res = localCache.has state.key1
+				res.should.eql false
+
 				ts = localCache.getTtl state.key1
 				should.not.exist ts
 

diff --git a/_src/test/typedefinition_test.ts b/_src/test/typedefinition_test.ts
@@ -78,6 +78,15 @@ interface TypeSample {
 	result = cache.keys(cb);
 }
 
+{
+	let cache: NodeCache;
+	let key: string | number;
+	let cb: Callback<boolean>;
+	let result: boolean;
+	result = cache.has(key);
+	result = cache.has(key, cb);
+}
+
 {
 	let cache: NodeCache;
 	let result: Stats;

diff --git a/index.d.ts b/index.d.ts
@@ -265,6 +265,14 @@ declare class NodeCache extends events.EventEmitter implements NodeCache.NodeCac
 	 */
 	keys(cb?: Callback<string[]>): string[];
 
+	/**
+	 * Check if a key is cached
+	 * @param key cache key to check
+	 * @param cb Callback function
+	 * @returns Boolean indicating if the key is cached or not
+	 */
+	has(key: Key, cb?: Callback<boolean>): boolean;
+
 	/**
 	 * get the stats
 	 *