ataraxia-services - npm Package Compare versions

Comparing version 0.4.4 to 0.5.0

index.js

@@ -19,2 +19,4 @@ 'use strict';
 		this.services = new Map();
+		this.version = 1;
+		this.nodes = new Map();
 
@@ -31,17 +33,45 @@ network.on('message', this._handleMessage.bind(this));
 	_handleNodeAvailable(node) {
-		/*
-		 * When we connect to a new node, send the node all of the local
-		 * services we provide.
-		 */
-		for(const service of this.services.values()) {
-			if(service instanceof LocalService) {
-				node.send('service:available', service.definition);
+		// Setup the node and initialize the version we have
+		const nodeData = {
+			node: node,
+			version: 0
+		};
+		this.nodes.set(node.id, nodeData);
+
+		// Request a list of services
+		node.send('service:list', { lastVersion: 0 });
+
+		// Schedule listing around every minute
+		function scheduleList() {
+			nodeData.listTimer = setTimeout(() => {
+				debug('Requesting list of services from', node);
+				node.send('service:list', { lastVersion: nodeData.version });
+				scheduleList();
+			}, 60000 + Math.random() * 5000);
+		}
+		scheduleList();
+
+		// Set a timer to fallback to broadcasting services
+		nodeData.broadcastTimer = setTimeout(() => {
+			nodeData.broadcastTimer = null;
+
+			for(const service of this.services.values()) {
+				if(service instanceof LocalService) {
+					node.send('service:available', service.definition);
+				}
 			}
-		}
+		}, 2000);
 	}
 
 	_handleNodeUnavailable(node) {
+		// Remove the node so we no longer query it
+		const nodeData = this.nodes.get(node.id);
+		clearTimeout(nodeData.listTimer);
+		clearTimeout(nodeData.broadcastTimer);
+		this.nodes.delete(node.id);
+
+		// Remove all the remote services of the node
 		for(const service of this.services.values()) {
 			if(service instanceof RemoteService && service.node.id === node.id) {
-				this._handleServiceUnavailable0(service);
+				this._handleServiceUnavailable0(node, service);
 			}
@@ -78,6 +108,12 @@ }
 	register(id, instance) {
+		// TODO: How should duplicate services be handled?
+
 		const service = new LocalService(this, id, instance);
 		this.services.set(id, service);
-		this.network.broadcast('service:available', service.definition);
 
+		// Update the version and broadcast this new service
+		this.version++;
+		const def = Object.assign({ servicesVersion: this.version }, service.definition);
+		this.network.broadcast('service:available', def);
+
 		this.events.emit('available', service.proxy);
@@ -98,4 +134,8 @@
 		this.services.delete(service.id);
-		this.network.broadcast('service:unavailable', service.definition);
 
+		// Update the version and broadcast that this service is no longer available
+		this.version++;
+		const def = Object.assign({ servicesVersion: this.version }, service.definition);
+		this.network.broadcast('service:unavailable', def);
+
 		this.events.emit('unavailable', service.proxy);
@@ -114,4 +154,17 @@ }
 
+	_serviceUpdated(service) {
+		// Update the version and broadcast the service
+		this.version++;
+		const def = Object.assign({ servicesVersion: this.version }, service.definition);
+		this.network.broadcast('service:available', def);
+	}
+
 	_handleMessage(msg) {
 		switch(msg.type) {
+			case 'service:list':
+				this._handleServiceList(msg.returnPath, msg.data);
+				break;
+			case 'service:list-result':
+				this._handleServiceListResult(msg.returnPath, msg.data);
+				break;
 			case 'service:available':
@@ -141,14 +194,115 @@ this._handleServiceAvailable(msg.returnPath, msg.data);
 
+	/**
+	 * Handle an incoming request to list services.
+	 *
+	 * Will check if anything has changed since the requested version and if
+	 * so sends back a complete list of services.
+	 */
+	_handleServiceList(node, data) {
+		// If the node has seen all of our services, skip reply
+		if(data.lastVersion === this.version) return;
+
+		// Mark that the other other node supports service listing, disable broadcast
+		const nodeData = this.nodes.get(node.id);
+		clearTimeout(nodeData.broadcastTimer);
+		nodeData.broadcastTimer = null;
+
+		// Collect the definitions for all of our local services
+		const services = [];
+		for(const service of this.services.values()) {
+			if(service instanceof LocalService) {
+				services.push(service.definition);
+			}
+		}
+
+		if(services.length > 0 || data.lastVersion === 0) {
+			// If we have any services send them back
+			node.send('service:list-result', {
+				servicesVersion: this.version,
+				services: services
+			});
+		}
+	}
+
+	/**
+	 * Handle an incoming result from a `service:list` request.
+	 */
+	_handleServiceListResult(node, data) {
+		// Figure out which services belong to the node
+		const servicesNoLongerAvailable = new Set();
+		for(const service of this.services.values()) {
+			if(service instanceof RemoteService && service.node.id === node.id) {
+				servicesNoLongerAvailable.add(service.id);
+			}
+		}
+
+		// Handle the incoming list of services
+		for(const service of data.services) {
+			// Remove from list of services that are unavailable
+			servicesNoLongerAvailable.delete(service.id);
+
+			// Add or update the service
+			this._handleServiceAvailable0(node, service);
+		}
+
+		// Remove the remaining services
+		for(const id of servicesNoLongerAvailable) {
+			const service = this.services.get(id);
+
+			this._handleServiceUnavailable0(service);
+		}
+
+		// Update the version we have seen
+		const nodeData = this.nodes.get(node.id);
+		nodeData.version = data.servicesVersion;
+	}
+
+	/**
+	 * Update the last version of a node or request a list of services if
+	 * there is a gap.
+	 */
+	_updateNodeVersion(node, data) {
+		if(! data.servicesVersion) return;
+
+		// Check the version being tracked for the node
+		const nodeData = this.nodes.get(node.id);
+		if(nodeData.version === data.servicesVersion - 1) {
+			// The version we have is the previous one, perform a simple update
+			nodeData.version = data.servicesVersion;
+		} else {
+			// There is a gap in our data, request the list of services
+			node.send('service:list', { lastVersion: nodeData.version });
+		}
+	}
+
+	/**
+	 * Handle that a new service is available or that it has been updated.
+	 */
 	_handleServiceAvailable(node, data) {
-		debug('Service', data.id, 'available via', node);
+		// Handle the incoming version information
+		this._updateNodeVersion(node, data);
 
+		// Actually handle the message
+		this._handleServiceAvailable0(node, data);
+	}
+
+	/**
+	 * Create or update a remote service based on its definition.
+	 */
+	_handleServiceAvailable0(node, data) {
 		let service = this.services.get(data.id);
 		if(! service) {
+			// This is a new service, create it and start tracking it
 			service = new RemoteService(this, node, data);
 			this.services.set(data.id, service);
 
+			debug('Service', data.id, 'available via', node);
 			this.events.emit('available', service.proxy);
 		} else {
-			service.updateDefinition(data);
-			this.events.emit('available', service.proxy);
+			// This is an existing service, update the definition
+			debug('Service', data.id, 'updated via', node);
+
+			if(service.updateDefinition(data)) {
+				this.events.emit('updated', service.proxy);
+			}
 		}
@@ -160,2 +314,5 @@ }
 
+		// Handle the incoming version information
+		this._updateNodeVersion(node, data);
+
 		// Get the service and protect against unknown service
@@ -165,9 +322,12 @@ let service = this.services.get(data.id);
 
-		this._handleServiceUnavailable0(service);
+		this._handleServiceUnavailable0(node, service);
 	}
 
-	_handleServiceUnavailable0(service) {
-		debug(service.id, 'is no longer available');
+	_handleServiceUnavailable0(node, service) {
+		debug('Service', service.id, 'is no longer available via', node);
 		this.services.delete(service.id);
 		this.events.emit('unavailable', service.proxy);
+
+		// Destroy the service object
+		service.destroy();
 	}
@@ -174,0 +334,0 @@

package-lock.json

 {
+	"name": "ataraxia-services",
+	"version": "0.4.4",
+	"lockfileVersion": 1,
 	"requires": true,
-	"lockfileVersion": 1,
 	"dependencies": {
+		"ataraxia": {
+			"version": "0.4.4",
+			"resolved": "https://registry.npmjs.org/ataraxia/-/ataraxia-0.4.4.tgz",
+			"integrity": "sha1-Zrfocc/YElWUxgB/ls0JrOA/W1Y=",
+			"requires": {
+				"debug": "3.1.0",
+				"deep-equal": "1.0.1",
+				"end-of-stream": "1.4.0",
+				"msgpack-lite": "0.1.26"
+			}
+		},
 		"debug": {
 			"version": "3.1.0",
 			"resolved": "https://registry.npmjs.org/debug/-/debug-3.1.0.tgz",
-			"integrity": "sha512-OX8XqP7/1a9cqkxYw2yXss15f26NKWBpDXQd0/uK/KPqdQhxbPa994hnzjcE2VqQpDslf55723cKPUOGSmMY3g==",
+			"integrity": "sha1-W7WgZyYotkFJVmuhaBnmFRjGcmE=",
 			"requires": {
@@ -13,2 +26,20 @@ "ms": "2.0.0"
 		},
+		"deep-equal": {
+			"version": "1.0.1",
+			"resolved": "https://registry.npmjs.org/deep-equal/-/deep-equal-1.0.1.tgz",
+			"integrity": "sha1-9dJgKStmDghO/0zbyfCK0yR0SLU="
+		},
+		"end-of-stream": {
+			"version": "1.4.0",
+			"resolved": "https://registry.npmjs.org/end-of-stream/-/end-of-stream-1.4.0.tgz",
+			"integrity": "sha1-epDYM+/abPpurA9JSduw+tOmMgY=",
+			"requires": {
+				"once": "1.4.0"
+			}
+		},
+		"event-lite": {
+			"version": "0.1.1",
+			"resolved": "https://registry.npmjs.org/event-lite/-/event-lite-0.1.1.tgz",
+			"integrity": "sha1-R88IqNN9C2lM23s7F7UfqsZXYIY="
+		},
 		"eventemitter2": {
@@ -19,2 +50,17 @@ "version": "4.1.2",
 		},
+		"ieee754": {
+			"version": "1.1.8",
+			"resolved": "https://registry.npmjs.org/ieee754/-/ieee754-1.1.8.tgz",
+			"integrity": "sha1-vjPUCsEO8ZJnAfbwii2G+/0a0+Q="
+		},
+		"int64-buffer": {
+			"version": "0.1.10",
+			"resolved": "https://registry.npmjs.org/int64-buffer/-/int64-buffer-0.1.10.tgz",
+			"integrity": "sha1-J3siiofZWtd30HwTgyAiQGpHNCM="
+		},
+		"isarray": {
+			"version": "1.0.0",
+			"resolved": "https://registry.npmjs.org/isarray/-/isarray-1.0.0.tgz",
+			"integrity": "sha1-u5NdSFgsuhaMBoNJV6VKPgcSTxE="
+		},
 		"ms": {
@@ -24,4 +70,28 @@ "version": "2.0.0",
 			"integrity": "sha1-VgiurfwAvmwpAd9fmGF4jeDVl8g="
+		},
+		"msgpack-lite": {
+			"version": "0.1.26",
+			"resolved": "https://registry.npmjs.org/msgpack-lite/-/msgpack-lite-0.1.26.tgz",
+			"integrity": "sha1-3TxQsm8FnyXn7e42REGDWOKprYk=",
+			"requires": {
+				"event-lite": "0.1.1",
+				"ieee754": "1.1.8",
+				"int64-buffer": "0.1.10",
+				"isarray": "1.0.0"
+			}
+		},
+		"once": {
+			"version": "1.4.0",
+			"resolved": "https://registry.npmjs.org/once/-/once-1.4.0.tgz",
+			"integrity": "sha1-WDsap3WWHUsROsF9nFC6753Xa9E=",
+			"requires": {
+				"wrappy": "1.0.2"
+			}
+		},
+		"wrappy": {
+			"version": "1.0.2",
+			"resolved": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",
+			"integrity": "sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8="
 		}
 	}
 }

package.json

 {
   "name": "ataraxia-services",
-  "version": "0.4.4",
+  "version": "0.5.0",
   "description": "Services with RPC and events over Ataraxia mesh network",
@@ -9,6 +9,7 @@ "main": "index.js",
   "dependencies": {
-    "ataraxia": "^0.4.4",
+    "ataraxia": "^0.5.0",
     "debug": "^3.1.0",
+    "deep-equal": "^1.0.1",
     "eventemitter2": "^4.1.2"
   }
 }

README.md

@@ -45,2 +45,40 @@ # ataraxia-services
 
-## Creat
+## Creating services
+
+Services are simple objects:
+
+```javascript
+services.register('service-id', {
+  hello(what='world') {
+    return 'Hello ' + what;
+  },
+
+  property: 1234
+});
+```
+
+The only special part of services is that the `metadata` property is
+automatically distributed througout the network.
+
+```javascript
+services.register('service-with-metadata', {
+  metadata: {
+    type: 'cookie-factory'
+  },
+  
+  cookiesMade: 0,
+
+  makeCookie() {
+    return ++this.cookiesMade;
+  }
+});
+```
+
+The metadata can be access on any node:
+
+```javascript
+const service = services.get('service-with-metadata');
+if(service) {
+  console.log(service.metadata.type);
+}
+```

service-local.js

@@ -73,3 +73,3 @@ 'use strict';
 	[metadataChanged]() {
-		this.parent.network.broadcast('service:available', this.definition);
+		this.parent._serviceUpdated(this);
 	}
@@ -76,0 +76,0 @@

service-remote.js

 'use strict';
 
 const Service = require('./service');
+const deepEqual = require('deep-equal');
 const customInspect = require('util').inspect.custom;
@@ -27,3 +28,8 @@
 	updateDefinition(def) {
-		this.metadata = def.metadata;
+		if(! deepEqual(this.metadata, def.metadata)) {
+			this.metadata = def.metadata;
+			return true;
+		}
+
+		return false;
 	}
@@ -126,3 +132,3 @@
 
-	remove() {
+	destroy() {
 		for(const promise of this.promises.values()) {
@@ -129,0 +135,0 @@ promise.reject(new Error('Service is no longer available'));

New alerts

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License

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Found 1 instance in 1 package

Fixed alerts

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License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

23009

increased by50.77%

Lines of code

713

increased by41.75%

Number of lines in readme file

84

increased by82.61%

Worsened metrics

Dependency count

4

increased by33.33%

Dependency changes

• + Addeddeep-equal@^1.0.1

• + Addedataraxia@0.5.2(transitive)

• + Addedhas-proto@1.1.0(transitive)

• + Addedhas-symbols@1.1.0(transitive)

• - Removedataraxia@0.4.4(transitive)

• - Removedhas-proto@1.0.3(transitive)

• - Removedhas-symbols@1.0.3(transitive)

• Updatedataraxia@^0.5.0