2.4.2 • Published 1 year ago
@castore/event-storage-adapter-postgres v2.4.2
Postgres Event Storage Adapter
DRY Castore EventStorageAdapter implementation using a Postgres database.
📥 Installation
# npm
npm install @castore/event-storage-adapter-postgres
# yarn
yarn add @castore/event-storage-adapter-postgresThis package has @castore/core as peer dependency, so you will have to install it as well:
# npm
npm install @castore/core
# yarn
yarn add @castore/core👩💻 Usage
import { PostgresEventStorageAdapter } from '@castore/event-storage-adapter-postgres';
const pokemonsEventStorageAdapter = new PostgresEventStorageAdapter({
// 👇 You can specify a connection string for your Postgres database
connectionString: 'postgresql://postgres:postgres@localhost:5432/postgres',
});
const pokemonsEventStore = new EventStore({
...
eventStorageAdapter: pokemonsEventStorageAdapter,
});🤔 How it works
This adapter simply persists events in a Postgres database.
Database Table Structure and Customization
Below is an overview of the underlying table structure used by the adapter and the available customization options when creating the event table.
Table Structure Overview
| Column | Data Type(s) | Default Customization | Description |
|---|---|---|---|
| id | BIGSERIAL (or SERIAL if specified via idType) | BIGSERIAL | Primary key; auto-incrementing identifier |
| aggregate_name | VARCHAR(aggregateNameLength) | VARCHAR(32) | Aggregate name (identifies the event store) |
| aggregate_id | UUID, ULID, or VARCHAR(aggregateId.length if type is VARCHAR) | UUID | Identifier for the aggregate; if using VARCHAR, a length must be specified |
| version | BIGINT (or INTEGER if specified via versionType) | BIGINT | Event version number |
| type | VARCHAR(typeLength) | VARCHAR(64) | Name of the event type |
| data | JSONB | n/a | Event payload stored in JSONB |
| metadata | JSONB | n/a | Additional event metadata |
| timestamp | TIMESTAMPTZ with DEFAULT CURRENT_TIMESTAMP(3) | CURRENT_TIMESTAMP(3) | Timestamp of the event (set automatically at insertion) |
| UNIQUE | (aggregate_name, aggregate_id, version) | n/a | Enforces that each combination of aggregate_name, aggregate_id, and version is unique |
Customizable Options in createEventTable
| Option | Default Value | Allowed Values / Description |
|---|---|---|
| tableName | event | Name of the table to be created |
| idType | BIGSERIAL | Database type for the id column; allowed values: BIGSERIAL or SERIAL |
| aggregateNameLength | 32 | Length for the aggregate_name VARCHAR column |
| aggregateId | { type: "UUID" } | Defines the aggregate_id column type; can be UUID, ULID, or VARCHAR (if using VARCHAR, a length must be provided) |
| versionType | BIGINT | Database type for the version column; allowed values: BIGINT or INTEGER |
| typeLength | 64 | Length for the type VARCHAR column |
Additionally, indexes are created on aggregate_name, version, and a composite index on (aggregate_name, aggregate_id) to enhance query performance.