Specialized components
Background processing
Service interaction layer
30 min
overview the service interaction layer provides a standardized mechanism for background tasks to communicate with other components of the ir engine it enables tasks to retrieve data, store results, and trigger actions without needing to understand the internal implementation details of those components by leveraging feathersjs services, the layer creates a consistent, modular approach to inter component communication this chapter explores how background tasks use the service interaction layer to access and manipulate data across the ir engine ecosystem purpose and functionality the service interaction layer serves several essential purposes standardized communication provides a consistent interface for accessing different parts of the system abstraction hides implementation details of data storage and processing decoupling reduces dependencies between components centralized logic keeps business logic within appropriate services testability enables easier testing through service mocking the layer enables background tasks to perform operations such as retrieving data from various sources creating or updating records triggering actions in other components subscribing to events and notifications accessing shared resources implementation feathersjs services the service interaction layer is built on feathersjs, a framework for real time applications and rest apis // example of a feathersjs service definition (not in the background processing project) // this would typically be in another part of the ir engine ecosystem app use('/channel', { async find(params) { // query the database for channels const channels = await db query('select from channels where active = true'); return channels; }, async create(data, params) { // create a new channel const result = await db query('insert into channels (name, type) values ($1, $2) returning ', \[data name, data type]); return result\[0]; }, // other methods get, update, patch, remove }); each service is registered with a unique path (e g , '/channel') implements standard methods (find, get, create, update, patch, remove) encapsulates the logic for a specific resource or functionality can use any data source or implementation internally accessing services background tasks access these services through the application instance // example from a background task async function collectchanneldata(app) { // get the channel service const channelservice = app service('channel'); // use the service to find active channels const activechannels = await channelservice find({ query { active true }, paginate false }); return activechannels; } the key components app service('service name') retrieves a reference to the specified service find() , create() , etc calls standard methods on the service parameters like query configure the service request common service methods the service interaction layer provides several standard methods find retrieves multiple records, often with filtering // find all active channels const activechannels = await app service('channel') find({ query { active true }, paginate false // get all results, not just the first page }); // find channels with specific criteria const gamechannels = await app service('channel') find({ query { category 'gaming', createdat { $gt new date('2023 01 01') } } }); get retrieves a single record by id // get a specific channel by id const channel = await app service('channel') get('channel 123'); create creates a new record // create a new analytics record const newrecord = await app service('analytics') create({ type 'activechannels', count 42, timestamp new date() }); update/patch updates existing records // update a record completely (replacing all fields) await app service('channel') update('channel 123', { name 'new name', active true, category 'general' }); // patch a record (updating only specified fields) await app service('channel') patch('channel 123', { active false }); remove deletes records // remove a specific record await app service('channel') remove('channel 123'); // remove multiple records matching criteria await app service('channel') remove(null, { query { temporary true, createdat { $lt yesterday } } }); practical examples analytics data collection the analytics data collector uses services to gather and store metrics // simplified from src/collect analytics ts async function collectandstoredata(app) { // get data from the channel service const activechannelslist = await app service('channel') find({ paginate false }); const activechannelscount = activechannelslist length; // store the result in the analytics service await app service('analytics') create({ type 'activechannels', count activechannelscount, timestamp new date() }); logger info(`stored channel count (${activechannelscount}) in analytics`); } this example demonstrates using the 'channel' service to retrieve data processing the data (counting channels) using the 'analytics' service to store the result kubernetes event processing the kubernetes event collector might use services to process and store events // simplified concept from src/collect events ts async function processkubernetesevent(app, event) { // check if this is a critical event if (event type === 'warning' && event reason === 'failed') { // create an alert using the alerts service await app service('alerts') create({ source 'kubernetes', level 'warning', message `${event involvedobject kind} ${event involvedobject name} ${event message}`, timestamp new date(event lasttimestamp) }); logger info(`created alert for kubernetes event ${event reason}`); } // store the event for historical records await app service('k8s events') create({ type event type, reason event reason, message event message, object `${event involvedobject kind}/${event involvedobject name}`, namespace event involvedobject namespace, timestamp new date(event lasttimestamp) }); } this example shows processing a kubernetes event using the 'alerts' service to create notifications for critical events using the 'k8s events' service to store all events for historical records service interaction flow the typical flow of service interaction follows these steps sequencediagram participant task as background task participant app as feathers app participant service as target service participant datastore as data store task >>app app service('service name') app >>task service reference task >>service service method(params) service >>datastore query/update data store datastore >>service return results service >>task return processed results this diagram illustrates the task requests a service reference from the app the task calls a method on the service with parameters the service interacts with its data store (database, api, etc ) the service processes the results and returns them to the task advanced service patterns hooks feathersjs services can use hooks for cross cutting concerns // example of service hooks (conceptual) app service('analytics') hooks({ before { create \[ // validate data before creation validateanalyticsdata(), // add timestamp if not provided addtimestamp() ] }, after { create \[ // notify other systems about new analytics notifydashboard() ] } }); hooks can validate input data transform data before or after service methods handle authentication and authorization log operations trigger side effects real time events services can emit events that other parts of the system can listen for // listening for service events app service('alerts') on('created', alert => { // react to new alerts if (alert level === 'critical') { sendemergencynotification(alert); } }); this enables real time updates across the system event driven architectures loose coupling between components pagination services can return paginated results for large datasets // using pagination const result = await app service('logs') find({ query { level 'error' }, $limit 25, $skip 0 }); // result structure with pagination // { // total 142, // limit 25, // skip 0, // data \[ / 25 log entries / ] // } this helps manage memory usage for large datasets improve performance enable efficient ui pagination integration with other components the service interaction layer integrates with several other components of the background processing system task server application the task server application provides the service access point // from src/start ts const app = await createfeatherskoaapp(servermode task); // pass the app to tasks, giving them access to services collectanalytics(app); collectevents(app); this integration initializes the feathersjs application registers all available services provides tasks with the entry point to services application configuration management services may use configuration to determine their behavior // example of a service using configuration app service('analytics') hooks({ before { create \[ async context => { // get storage limit from configuration const storagelimit = config analytics storagelimit; // check if we need to clean up old records const count = await getanalyticscount(); if (count > storagelimit) { await cleanupoldanalytics(storagelimit); } return context; } ] } }); this integration allows services to adapt to configuration enables environment specific service behavior supports runtime adjustments to service parameters periodic task scheduler tasks scheduled by the periodic task scheduler often use services // from a task using setinterval setinterval(async () => { try { // use services within the periodic task const data = await app service('some service') find(); await processdata(app, data); } catch (error) { logger error('error in periodic task ', error); } }, intervalmilliseconds); this integration enables periodic tasks to access and update data allows scheduled operations to interact with other components maintains separation between scheduling and service interaction benefits of the service interaction layer the service interaction layer provides several key benefits consistency provides a uniform interface across different resources modularity allows components to be developed and tested independently abstraction hides implementation details behind a standard interface flexibility enables services to change their internal implementation without affecting clients testability makes it easier to mock services for testing scalability supports distributed architectures and service separation maintainability centralizes resource specific logic in appropriate services these benefits make the service interaction layer a critical component for enabling effective communication between background tasks and other parts of the ir engine next steps with an understanding of how background tasks interact with services to retrieve and store data, the next chapter explores a specific task that monitors the kubernetes environment next kubernetes event collector docid\ gfdlk sf1elkjnrh5i8ab