systemprompt_database/services/postgres/
connection.rs

1//! Initial-connect retry policy for `PostgresProvider`.
2//!
3//! Wraps the first `PgPool` connect in a bounded exponential backoff so
4//! transient startup races (Postgres still booting, SSL handshake racing
5//! the TCP listener) recover without surfacing as user-visible failures.
6//! The retry loop intentionally targets a narrow set of error shapes so
7//! permanent failures (auth, missing database, bad URL) fail fast. The
8//! backoff itself runs on [`crate::resilience::retry::retry_async`].
9//!
10//! Copyright (c) systemprompt.io — Business Source License 1.1.
11//! See <https://systemprompt.io> for licensing details.
12
13use std::future::Future;
14use std::time::Duration;
15
16use sqlx::postgres::{PgConnectOptions, PgPool, PgPoolOptions};
17
18use crate::error::DatabaseResult;
19use crate::resilience::classify::Outcome;
20use crate::resilience::config::RetryConfig;
21use crate::resilience::retry::retry_async;
22
23const RETRY_DELAYS_MS: &[u64] = &[100, 200, 400, 800, 1600];
24const MAX_ATTEMPTS: u32 = 5;
25
26/// Operator-tunable connection-pool sizing for a `PostgresProvider`.
27///
28/// [`PoolConfig::default`] reproduces the historical hardcoded values; callers
29/// that have profile config supply their own. The connect/SSL/retry behaviour
30/// is fixed and not exposed here — only the sizing/lifetime knobs an operator
31/// needs to fit the pool to their Postgres `max_connections` and replica count.
32#[derive(Debug, Clone, Copy)]
33pub struct PoolConfig {
34    pub max_connections: u32,
35    pub min_connections: u32,
36    pub acquire_timeout: Duration,
37    pub idle_timeout: Duration,
38    pub max_lifetime: Duration,
39}
40
41impl Default for PoolConfig {
42    fn default() -> Self {
43        Self {
44            max_connections: 50,
45            min_connections: 0,
46            acquire_timeout: Duration::from_secs(30),
47            idle_timeout: Duration::from_mins(5),
48            max_lifetime: Duration::from_mins(30),
49        }
50    }
51}
52
53#[must_use]
54pub fn build_pool_options(cfg: &PoolConfig) -> PgPoolOptions {
55    PgPoolOptions::new()
56        .max_connections(cfg.max_connections)
57        .min_connections(cfg.min_connections)
58        .max_lifetime(cfg.max_lifetime)
59        .acquire_timeout(cfg.acquire_timeout)
60        .idle_timeout(cfg.idle_timeout)
61}
62
63pub async fn connect_with_retry(
64    options: PgPoolOptions,
65    connect_options: PgConnectOptions,
66) -> DatabaseResult<PgPool> {
67    let connector = |opts: PgConnectOptions| {
68        let options = options.clone();
69        async move { options.connect_with(opts).await }
70    };
71    connect_with_retry_using(connect_options, MAX_ATTEMPTS, RETRY_DELAYS_MS, connector).await
72}
73
74pub async fn connect_with_retry_using<T, F, Fut>(
75    connect_options: PgConnectOptions,
76    max_attempts: u32,
77    delays_ms: &[u64],
78    connector: F,
79) -> DatabaseResult<T>
80where
81    T: Send,
82    F: Fn(PgConnectOptions) -> Fut + Send + Sync,
83    Fut: Future<Output = Result<T, sqlx::Error>> + Send,
84{
85    let cfg = RetryConfig {
86        max_attempts,
87        base_delay: Duration::from_millis(delays_ms.first().copied().unwrap_or(100)),
88        max_delay: Duration::from_millis(delays_ms.iter().copied().max().unwrap_or(1600)),
89        jitter: false,
90    };
91    let classify = |err: &sqlx::Error| {
92        if is_retryable(err) {
93            Outcome::Transient { retry_after: None }
94        } else {
95            Outcome::Permanent
96        }
97    };
98    retry_async(&cfg, "postgres-connect", classify, || {
99        connector(connect_options.clone())
100    })
101    .await
102    .map_err(Into::into)
103}
104
105fn is_retryable(err: &sqlx::Error) -> bool {
106    if let sqlx::Error::Io(io_err) = err
107        && io_err.kind() == std::io::ErrorKind::ConnectionRefused
108    {
109        return true;
110    }
111    let msg = err.to_string();
112    msg.contains("unexpected response from SSLRequest") || msg.contains("starting up")
113}
systemprompt_database/services/postgres/connection.rs

systemprompt_database/services/postgres/
connection.rs
