Architecture

zero follows the dependency injection pattern and allows the abstractions to be centered around with main three components.

• App
• Container
• Context

App - Orchestrator

App orchestractes the application life cycle, manages the framework functionality.

App references to all major sub-systems and provides methods to access and execute the configurations, routing, logging, registered migrations and over all life-cycle

App is the main entry point for the zero app.

App key accessible methods

App Lifecyle

Methods explaination

const app = try App.new(allocator);

new() launches the zero app instance, and coordinates and creates all underlying sub-systems if the valid configurations are available.

try app.get("path", custom-handler);

get(), post(), patch(), delete() integrates the custom handlers to the http router and allows the resource endpoints to be responded on matched requests.

try app.addMigration(key, migrateHanlder);

addMigration() attaches the data model migrations to be executed on the application run. migrateHandler has to follow the migrate struct signature to execute correctly.

try app.runMigrations();

runMigrations() executes one or more migrations that has been attached in above steps, skips if the app found the migrations were already executed in it is flow.

try app.addCronJob("schedule-notation", "task-name", taskHandler);

addCronJob() comes handy to execute any repeatable jobs for the app has to perform.

try app.addSubscription(pubSubTopic, subscribeHandler);

addSubscription() allows app to subscribe to pubsub topic to perform needed actions.

try app.onStatup(prepareCache);

onStartup synchronize any needed actions for the app to perform before serving any requests such as warming up the cache, taking backups.

try app.addHttpService("external-service", "service-url");

addHttpService() help the developer to register any external http/https service to be associated with app life time and enables the service-to-service communications possible with minimal coding.

try app.addWebsocket(socketHandler);

addWebsocket enables the app to upgrade and stream the bi-directional communications to the client over websockets.