Service Creation

Creating a Service

The Phestus Service provides an abstraction between Phestus and the underlying data system used by your application.

Instead of Phestus modules directly depending on a specific database, CMS, or ORM, they interact with the PhestusService interface.

This allows the same Phestus modules to work with different implementations of your application's data layer.

A service contains two primary areas:

• schema - Defines and manages Phestus schemas.
• data - Provides operations for reading and modifying data.

Creating a Simple Service

A basic service can be created by implementing the PhestusService interface.

import type {
    PhestusService,
} from '@phestus/sdk'

export const service: PhestusService = {
    schema: {
        async get(collection) {
            return null
        },

        async exists(collection) {
            return false
        },

        async create(collection, schema) {},
        async update(collection, schema) {},
        async ensure(collection, schema) {},
    },

    data: {
        async find(collection, query) {
            return {
                docs: [],
                totalDocs: 0,
                limit: query?.limit ?? 10,
                offset: query?.offset ?? 0,
                hasNextPage: false,
                hasPrevPage: false,
            }
        },

        async findById(collection, id) {
            return null
        },

        async count(collection, query) {
            return 0
        },

        async create(collection, data) {
            return data
        },

        async update(collection, id, data) {
            return data
        },

        async delete(collection, id) {
            return null
        },
    },
}

This example is only a basic implementation. In a real application, these methods would connect to your database, CMS, ORM, or another data source.

Adding the Service to Phestus

The service is provided through the PhestusConfig:

import type { PhestusConfig } from '@phestus/sdk'

export const config: PhestusConfig = {
    service,
    logger,
    eventBus,
}

Phestus then provides the service to modules through the PhestusContext.

const context: PhestusContext = {
    service,
    logger,
    eventBus,
}

Modules can use the service without needing to know what system is actually providing the data.

For example:

const result = await context.service.data.find(
    'users',
    {
        limit: 10,
    },
)

The module only knows that it is using the PhestusService interface. The actual implementation could be backed by Payload, PostgreSQL, Redis, an ORM, or another system.

Next Steps

The service system provides much more functionality than this basic implementation. The Services section covers:

• Data queries and operators
• Creating and managing schemas
• Service adapters
• Data operations
• Schema validation
• Building custom service implementations