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"
factstr-postgres = "0.3"

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