factstr-postgres

factstr-postgres is the PostgreSQL-backed store implementation for the shared factstr contract.

Use this crate when an application already operates PostgreSQL and wants FACTSTR persistence there.

What it implements

factstr-postgres implements the shared factstr::EventStore contract, including:

append
query
append_if
stream_all
stream_to
stream_all_durable
stream_to_durable

When to use it

Use factstr-postgres when:

you want FACTSTR backed by PostgreSQL
your application already operates PostgreSQL
you want durable stream cursor state to persist in PostgreSQL

Store behavior and boundaries

Committed facts and durable stream cursors are stored in PostgreSQL.
SQL transactions and indexes are used internally.
An internal worker thread keeps the synchronous store API safe to call from inside a running Tokio runtime.
Durable replay depends on persisted append-batch history.
Older databases without contiguous append-batch history are rejected for durable replay instead of being silently backfilled.

Integration tests for this crate require a PostgreSQL database.

Add to `Cargo.toml`

[dependencies]
factstr = "0.3.1"
factstr-postgres = "0.3.1"
serde_json = "1"

Minimal example

use factstr::{EventQuery, EventStore, NewEvent};
use factstr_postgres::PostgresStore;
use serde_json::json;
use std::env;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let database_url = env::var("DATABASE_URL")?;
    let store = PostgresStore::connect(&database_url)?;

    store.append(vec![NewEvent {
        event_type: "item-added".to_owned(),
        payload: json!({ "sku": "ABC-123", "quantity": 1 }),
    }])?;

    let result = store.query(&EventQuery::all())?;
    assert_eq!(result.event_records.len(), 1);

    Ok(())
}

Related crates

factstr: shared contract and core types
factstr-memory: in-memory store
factstr-sqlite: embedded persistent store

License

Licensed under either of:

MIT license
Apache License, Version 2.0

factstr-postgres 0.3.1