1
1
mirror of https://github.com/namibia/awesome-cheatsheets.git synced 2024-11-21 12:25:14 +00:00
awesome-cheatsheets/backend/moleculer.js
2018-03-10 17:11:24 -08:00

748 lines
22 KiB
JavaScript
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* *******************************************************************************************
* MOLECULER MICROSERVICES FRAMEWORK - CORE CHEATSHEET
* http://moleculer.services/0.12/docs/
*
* Version: 0.12.x
* ******************************************************************************************* */
/* *******************************************************************************************
* Install Moleculer
* ******************************************************************************************* */
```bash
npm i moleculer
```
/* *******************************************************************************************
* SERVICE BROKER OPTIONS
* ******************************************************************************************* */
// All ServiceBroker options with default values
const broker = new ServiceBroker({
namespace: "", // Namespace for node segmentation
nodeID: null, // NodeID. Default value is generated from hostname and PID
logger: null, // Logger instance.
logLevel: null, // Log level
logFormatter: "default", // Log formatter. Options: "default", "simple"
transporter: null, // Transporter config
requestTimeout: 0 * 1000, // Timeout of requests
requestRetry: 0, // Retries for requests
maxCallLevel: 0, // Maximum calling level.
heartbeatInterval: 5, // Heartbeat sending interval in seconds
heartbeatTimeout: 15, // Heartbeat timeout in seconds
disableBalancer: false, // Disable the built-in Moleculer balancer
registry: { // Service Registry options
strategy: "RoundRobin", // Invocation strategy
strategyOptions: null, // Strategy options
preferLocal: true // Prefer local invocations
},
circuitBreaker: { // Circuit-breaker options
enabled: false, // Enable circuit-breaker
maxFailures: 3, // Maximum failures
halfOpenTime: 10 * 1000, // Half-open time interval
failureOnTimeout: true, // Failure on timeouts
failureOnReject: true // Failure on rejects
},
transit: { // Transit options
maxQueueSize: 50 * 1000 // Max items in outgoing queue
},
cacher: null, // Cacher config
serializer: null, // Serializer config
validation: true, // Enable params validation
validator: null, // Validator instance
metrics: false, // Enable metrics
metricsRate: 1, // Metrics rate
statistics: false, // Enable statistics
internalServices: true, // Load internal ($node) services
hotReload: false, // Hot-reload services
middlewares: null, // List of middlewares
replCommands: null, // Custom REPL commands
ServiceFactory: null, // Custom Service factory class
ContextFactory: null // Custom Context factory class
});
/* *******************************************************************************************
* SERVICE BROKER METHODS
* ******************************************************************************************* */
// Broker properties
broker.Promise // Pointer to Bluebird Promise lib
broker.namespace // Namespace from options
broker.nodeID // Local NodeID
broker.logger // Logger instance
broker.cacher // Cacher instance
broker.serializer // Serializer instance
broker.validator // Validator instance
// Broker methods
broker.start(); // Start broker & all services. Returns a Promise
broker.stop(); // Stop broker & all services. Returns a Promise
broker.fatal(message, err, needExit = true); // Fired a fatal error.
broker.repl(); // Switch broker to REPL mode.
broker.getLogger(module, service, version); // Create a custom logger instance for modules
broker.loadServices(folder, fileMask); // Load all services from directory
broker.loadService(filePath); // Load a service from a file
broker.createService(schema, schemaMods); // Create a local service from schema
broker.destroyService(service); // Destroy a local service
broker.getLocalService(name, version); // Get a local service instance by name
// Wait for services. Returns a Promise
await broker.waitForServices(serviceNames, timeout, interval);
await broker.waitForServices(["posts", "users"], 5000);
await broker.waitForServices({
name: "posts", version: 2,
name: "users", version: 1
}, 5000);
broker.use(...middlewares); // Register middlewares
broker.call(actionName, params, opts); // Call a service
broker.mcall(def); // Multiple service calls
broker.emit(eventName, payload, groups); // Emit a balanced event
broker.broadcast(eventName, payload, groups = null) // Broadcast an event
broker.broadcastLocal(eventName, payload, groups = null) // Broadcast an event to local services
broker.sendPing(nodeID); // Ping a remote node
broker.MOLECULER_VERSION // Version number of Moleculer lib
broker.PROTOCOL_VERSION // Version number of Moleculer protocol
/* *******************************************************************************************
* BROKER SERVICE CALLS
* ******************************************************************************************* */
// Call the "users.get" service with params
broker.call("users.get", { id: 150 }).then(user => console.log(user));
// Call with async/await
const user = await broker.call("users.get", { id: 150});
// Call with calling options
const user = await broker.call("users.get", { id: 150}, { timeout: 5000, retryCount: 3 });
// Direct call to a remote node
const info = await broker.call("$node.services", null, { nodeID: "node-123" });
// Multiple calls with array def
const [posts, users] = await broker.mcall([
{ action: "posts.find", params: { limit: 5, offset: 0 } },
{ action: "users.find", params: { limit: 5, sort: "username" }, opts: { timeout: 500 } }
]);
// Multip calls with object def
const res = await broker.mcall({
posts: { action: "posts.find", params: { limit: 5, offset: 0 } },
users: { action: "users.find", params: { limit: 5, sort: "username" }, opts: { timeout: 500 } }
});
console.log(res.posts, res.users);
/* *******************************************************************************************
* BROKER EVENTS
* ******************************************************************************************* */
// Send a balanced event with payload
broker.emit("user.created", { user: user });
// Send a balanced event only for "mail" and "payment" service (only one instance)
broker.emit("user.created", { user: user }, ["mail", "payment"]);
// Send a broadcast event (for all service instances)
broker.broadcast("user.created", { user: user });
// Send a broadcast event only for "mail" and "payment" services (all instances)
broker.broadcast("user.created", { user: user }, ["mail", "payment"]);
/* *******************************************************************************************
* NATS TRANSPORTER
* Requirement: `npm i nats`
* ******************************************************************************************* */
// Default options
const broker = new ServiceBroker({
transporter: "NATS"
});
// With URI
const broker = new ServiceBroker({
transporter: "nats://localhost:4222"
});
// With options
const broker = new ServiceBroker({
transporter: {
type: "NATS",
options: {
url: "nats://localhost:4222",
user: "admin",
pass: "1234"
}
}
});
// With TLS (https://github.com/nats-io/node-nats#tls)
const broker = new ServiceBroker({
transporter: {
type: "NATS",
options: {
url: "nats://localhost:4222",
tls: {
key: fs.readFileSync('./client-key.pem'),
cert: fs.readFileSync('./client-cert.pem'),
ca: [ fs.readFileSync('./ca.pem') ]
}
}
}
});
/* *******************************************************************************************
* REDIS TRANSPORTER
* Requirement: `npm i ioredis`
* ******************************************************************************************* */
// Default options
const broker = new ServiceBroker({
transporter: "Redis"
});
// With URI
const broker = new ServiceBroker({
transporter: "redis://redis-server:6379"
});
// With options
const broker = new ServiceBroker({
transporter: {
type: "Redis",
options: {
port: 6379, // Redis port
host: 'redis-server', // Redis host
family: 4, // 4 (IPv4) or 6 (IPv6)
password: 'auth', // Password
db: 0 // Database index
}
}
});
/* *******************************************************************************************
* MQTT TRANSPORTER
* Requirement: `npm i mqtt`
* ******************************************************************************************* */
// Default options
const broker = new ServiceBroker({
transporter: "MQTT"
});
// With URI
const broker = new ServiceBroker({
transporter: "mqtt://mqtt-server:1883"
});
// With options
const broker = new ServiceBroker({
transporter: {
type: "MQTT",
options: {
host: "mqtt-server",
port: 1883,
username: "admin",
password: "1234"
}
}
});
/* *******************************************************************************************
* AMQP TRANSPORTER
* Requirement: `npm i amqplib`
* ******************************************************************************************* */
// Default options
const broker = new ServiceBroker({
transporter: "AMQP"
});
// With URI
const broker = new ServiceBroker({
transporter: "amqp://rabbitmq-server:5672"
});
// With options
const broker = new ServiceBroker({
transporter: {
type: "AMQP",
options: {
url: "amqp://user:pass@rabbitmq-server:5672",
eventTimeToLive: 5000,
prefetch: 1
}
}
});
/* *******************************************************************************************
* KAFKA TRANSPORTER
* Requirement: `npm i kafka-node`
* ******************************************************************************************* */
// Default options
const broker = new ServiceBroker({
transporter: "Kafka"
});
// With URI
const broker = new ServiceBroker({
transporter: "kafka://192.168.51.29:2181"
});
// With options
const broker = new ServiceBroker({
transporter: {
type: "kafka",
options: {
host: "192.168.51.29:2181",
// KafkaClient options. More info: https://github.com/SOHU-Co/kafka-node#clientconnectionstring-clientid-zkoptions-noackbatchoptions-ssloptions
client: {
zkOptions: undefined,
noAckBatchOptions: undefined,
sslOptions: undefined
},
// KafkaProducer options. More info: https://github.com/SOHU-Co/kafka-node#producerclient-options-custompartitioner
producer: {},
customPartitioner: undefined,
// ConsumerGroup options. More info: https://github.com/SOHU-Co/kafka-node#consumergroupoptions-topics
consumer: {
},
// Advanced options for `send`. More info: https://github.com/SOHU-Co/kafka-node#sendpayloads-cb
publish: {
partition: 0,
attributes: 0
}
}
}
});
/* *******************************************************************************************
* NATS STREAMING TRANSPORTER
* Requirement: `npm i node-nats-streaming`
* ******************************************************************************************* */
// Default options
const broker = new ServiceBroker({
transporter: "STAN"
});
// With URI
const broker = new ServiceBroker({
transporter: "stan://192.168.0.120:4222"
});
// With options
const broker = new ServiceBroker({
transporter: {
type: "STAN",
options: {
url: "stan://127.0.0.1:4222",
clusterID: "my-cluster"
}
}
});
/* *******************************************************************************************
* TCP STREAMING TRANSPORTER
* No requirements
* ******************************************************************************************* */
// Default options
const broker = new ServiceBroker({
transporter: "TCP"
});
// With static node list
const broker = new ServiceBroker({
transporter: "tcp://172.17.0.1:6000/node-1,172.17.0.2:6000/node-2"
});
const broker = new ServiceBroker({
nodeID: "node-1",
transporter: {
type: "TCP",
options: {
udpDiscovery: false,
urls: [
"172.17.0.1:6000/node-1",
"172.17.0.2:6000/node-2",
"172.17.0.3:6000/node-3"
]
}
}
});
// With full options
const broker = new ServiceBroker({
logger: true,
transporter: {
type: "TCP",
options: {
// Enable UDP discovery
udpDiscovery: true,
// Reusing UDP server socket
udpReuseAddr: true,
// UDP port
udpPort: 4445,
// UDP bind address
udpBindAddress: null,
// UDP sending period
udpPeriod: 5,
// Multicast address.
udpMulticast: "239.0.0.0",
// Multicast TTL setting
udpMulticastTTL: 1,
// Send broadcast
udpBroadcast: false,
// TCP server port. Null or 0 means random port
port: null,
// Static remote nodes address list (when UDP discovery is not available)
urls: null,
// Use hostname as preffered connection address
useHostname: true,
// Gossip sending period in seconds
gossipPeriod: 2,
// Maximum enabled outgoing connections. If reach, close the old connections
maxConnections: 32,
// Maximum TCP packet size
maxPacketSize: 1 * 1024 * 1024
}
}
});
/* *******************************************************************************************
* CACHERS
* http://moleculer.services/docs/cachers.html
* ******************************************************************************************* */
// Memory cacher
const broker = new ServiceBroker({
cacher: "Memory"
});
// or
const broker = new ServiceBroker({
cacher: true
});
// Memory cacher with options
const broker = new ServiceBroker({
cacher: {
type: "Memory",
options: {
ttl: 30
}
}
});
// Redis cacher
const broker = new ServiceBroker({
cacher: "Redis"
});
// Redis cacher with URI
const broker = new ServiceBroker({
cacher: "redis://redis-server:6379"
});
// Redis cacher with options
const broker = new ServiceBroker({
cacher: {
type: "Redis",
options: {
prefix: "MOL",
redis: {
host: "redis",
port: 6379,
password: "1234",
db: 0
}
}
}
});
/* *******************************************************************************************
* Manual caching
* ******************************************************************************************* */
// Save to cache
broker.cacher.set("mykey.a", { a: 5 });
// Get from cache
const obj = await broker.cacher.get("mykey.a");
// Remove entry from cache
broker.cacher.del("mykey.a");
// Clean all 'mykey' entries
broker.cacher.clean("mykey.*");
// Clean all entries
broker.cacher.clean();
/* *******************************************************************************************
* SERIALIZER
* http://moleculer.services/docs/serializers.html
* ******************************************************************************************* */
// JSON serializer (default)
const broker = new ServiceBroker({
serializer: "JSON"
});
// Avro serializer (need `npm i avsc`)
const broker = new ServiceBroker({
serializer: "Avro"
});
// Protocol Buffer serializer (need `npm i protobufjs`)
const broker = new ServiceBroker({
serializer: "ProtoBuf"
});
// MsgPack serializer (need `npm i msgpack5`)
const broker = new ServiceBroker({
serializer: "MsgPack"
});
/* *******************************************************************************************
* STRATEGY
* ******************************************************************************************* */
// Round-robin strategy (default)
const broker = new ServiceBroker({
registry: {
strategy: "RoundRobin"
}
});
// Random strategy
const broker = new ServiceBroker({
registry: {
strategy: "Random"
}
});
// CPU usage-based strategy
const broker = new ServiceBroker({
registry: {
strategy: "CpuUsageStrategy"
}
});
// CPU usage-based strategy with options
const broker = new ServiceBroker({
registry: {
strategy: "CpuUsageStrategy",
strategyOptions: {
sampleCount: 3,
lowCpuUsage: 10
}
}
});
/* *******************************************************************************************
* LOGGER
* http://moleculer.services/docs/logger.html
* ******************************************************************************************* */
// Logger methods
broker.logger.fatal();
broker.logger.error();
broker.logger.warn();
broker.logger.info();
broker.logger.debug();
broker.logger.trace();
// Custom log formatter
const broker = new ServiceBroker({
logger: console,
logFormatter(level, args, bindings) {
return level.toUpperCase() + " " + bindings.nodeID + ": " + args.join(" ");
}
});
// External Pino logger
const pino = require("pino")({ level: "info" });
const broker = new ServiceBroker({
logger: bindings => pino.child(bindings)
});
// External Bunyan logger
const logger = require("bunyan").createLogger({ name: "moleculer", level: "info" });
const broker = new ServiceBroker({
logger: bindings => logger.child(bindings)
});
/* *******************************************************************************************
* SERVICE SCHEMA
* ******************************************************************************************* */
module.exports = {
// Name
name: "greeter",
// Version
version: 2,
// Settings
settings: {},
// Metadata
metadata: {},
// Dependencies
dependencies: [],
// Actions
actions: {
// Shorthand actions
hello() {
// Call a method
this.doSomething();
return "Hello Moleculer";
},
// With properties
welcome: {
// Cache options
cache: {
keys: ["name"]
},
// Validation options
params: {
name: "string"
},
// Action handler
handler(ctx) {
return `Welcome, ${ctx.params.name}`;
}
}
},
events: {
"user.created"(payload, sender) {
}
},
// Service methods
methods: {
doSomething() {}
},
// Lifecycle event handlers
created() {
console.log("Service created");
},
started() {
console.log("Service started");
return Promise.resolve();
},
stopped() {
console.log("Service stopped");
return Promise.resolve();
}
};
/* *******************************************************************************************
* SERVICE
* ******************************************************************************************* */
this.name // Name of service
this.version // Version of service
this.settings // Settings of service
this.schema // Schema definition of service
this.broker // Broker instance
this.Promise // Class of Promise (Bluebird)
this.logger // Logger instance
this.actions // Actions of service.
this.waitForServices // Pointer to broker.waitForServices method
/* *******************************************************************************************
* CONTEXT
* ******************************************************************************************* */
ctx.id // Context ID
ctx.broker // Broker instance
ctx.action // Action definition
ctx.nodeID // Node ID
ctx.requestID // Request ID
ctx.parentID // ID of parent context (in case of sub-calls).
ctx.params // Request params
ctx.meta // Request metadata
ctx.callerNodeID // Caller Node ID if it is requested from a remote node.
ctx.level // Request level (in case of sub-calls). The first level is 1.
// Make a sub-call
ctx.call(actionName, params, callingOptions)
// Emit an event
ctx.emit(eventName, payload, groups);