fix(app-proxy): honour the shared Postgres settings (#2262)

deploy/self-hosting/docker-compose.yml

@@ -1,6 +1,17 @@
 name: fluxer
 
+x-fluxer-postgres-env: &fluxer-postgres-env
+  FLUXER_DATABASE_BACKEND: postgres
+  FLUXER_POSTGRES_HOST: postgres
+  FLUXER_POSTGRES_PORT: "5432"
+  FLUXER_POSTGRES_DATABASE: fluxer
+  FLUXER_POSTGRES_USERNAME: fluxer
+  FLUXER_POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:?set POSTGRES_PASSWORD in .env}
+  FLUXER_POSTGRES_SSL: "false"
+  FLUXER_POSTGRES_PREPARED_STATEMENTS: ${FLUXER_POSTGRES_PREPARED_STATEMENTS:-true}
+
 x-fluxer-env: &fluxer-env
+  <<: *fluxer-postgres-env
   FLUXER_ENV: production
   NODE_ENV: production
   FLUXER_SELF_HOSTED: "true"
@@ -12,15 +23,6 @@ x-fluxer-env: &fluxer-env
   FLUXER_API_HEADERS_TIMEOUT_MS: ${FLUXER_API_HEADERS_TIMEOUT_MS:-30000}
   FLUXER_API_REQUEST_TIMEOUT_MS: ${FLUXER_API_REQUEST_TIMEOUT_MS:-120000}
 
-  FLUXER_DATABASE_BACKEND: postgres
-  FLUXER_POSTGRES_HOST: postgres
-  FLUXER_POSTGRES_PORT: "5432"
-  FLUXER_POSTGRES_DATABASE: fluxer
-  FLUXER_POSTGRES_USERNAME: fluxer
-  FLUXER_POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:?set POSTGRES_PASSWORD in .env}
-  FLUXER_POSTGRES_SSL: "false"
-  FLUXER_POSTGRES_PREPARED_STATEMENTS: ${FLUXER_POSTGRES_PREPARED_STATEMENTS:-true}
-
   FLUXER_KV_URL: redis://valkey:6379/0
   FLUXER_NATS_URL: nats://nats:4222
   FLUXER_NATS_JETSTREAM_URL: nats://nats:4222
@@ -412,6 +414,7 @@ services:
         limits:
           memory: ${FLUXER_APP_PROXY_MEMORY_LIMIT:-256mb}
     environment:
+      <<: *fluxer-postgres-env
       FLUXER_APP_PROXY_HOST: 0.0.0.0
       FLUXER_APP_PROXY_PORT: "8080"
       DISCOVERY_UPSTREAM_URL: http://caddy:8088/api/.well-known/fluxer

fluxer_app_proxy/src/config.rs

@@ -251,10 +251,7 @@ impl AppProxyConfig {
             postgres_ssl_ca: cfg::non_empty_env("FLUXER_POSTGRES_SSL_CA"),
             postgres_max_connections,
             postgres_kv_table: cfg::read_env("FLUXER_POSTGRES_KV_TABLE", "fluxer_kv"),
-            postgres_prepared_statements: cfg::read_bool_env(
-                &["FLUXER_POSTGRES_PREPARED_STATEMENTS"],
-                true,
-            ),
+            postgres_prepared_statements: resolve_postgres_prepared_statements_from_env(),
         }
     }
 }
@@ -274,6 +271,10 @@ fn resolve_time_freeze_enabled_from_env() -> bool {
     resolve_time_freeze_enabled(|name| env::var(name).ok())
 }
 
+fn resolve_postgres_prepared_statements_from_env() -> bool {
+    resolve_postgres_prepared_statements(|name| env::var(name).ok())
+}
+
 fn resolve_time_freeze_enabled<F>(mut read_var: F) -> bool
 where
     F: FnMut(&str) -> Option<String>,
@@ -292,6 +293,31 @@ fn parse_boolish(value: &str) -> bool {
     )
 }
 
+fn resolve_postgres_prepared_statements<F>(mut read_var: F) -> bool
+where
+    F: FnMut(&str) -> Option<String>,
+{
+    let Some(value) = read_var("FLUXER_POSTGRES_PREPARED_STATEMENTS")
+        .map(|value| value.trim().to_ascii_lowercase())
+        .filter(|value| !value.is_empty())
+    else {
+        return true;
+    };
+
+    match value.as_str() {
+        "1" | "true" | "yes" | "y" | "on" => true,
+        "0" | "false" | "no" | "n" | "off" => false,
+        other => {
+            tracing::warn!(
+                env = "FLUXER_POSTGRES_PREPARED_STATEMENTS",
+                value = other,
+                "invalid value; falling back to default"
+            );
+            true
+        }
+    }
+}
+
 fn resolve_discovery_upstream_url<F>(mut read_var: F) -> String
 where
     F: FnMut(&str) -> Option<String>,
@@ -342,6 +368,11 @@ mod tests {
         resolve_time_freeze_enabled(|name| env.get(name).map(|value| value.to_string()))
     }
 
+    fn resolve_prepared_statements_from_pairs(pairs: &[(&str, &str)]) -> bool {
+        let env: HashMap<&str, &str> = pairs.iter().copied().collect();
+        resolve_postgres_prepared_statements(|name| env.get(name).map(|value| value.to_string()))
+    }
+
     #[test]
     fn csp_config_default_has_no_extra_sources() {
         let c = CspConfig::default();
@@ -429,6 +460,43 @@ mod tests {
         );
     }
 
+    #[test]
+    fn a_set_but_empty_prepared_statements_value_keeps_the_shared_default() {
+        assert!(resolve_prepared_statements_from_pairs(&[]));
+        assert!(
+            resolve_prepared_statements_from_pairs(&[("FLUXER_POSTGRES_PREPARED_STATEMENTS", "")]),
+            "an empty value disabled named statements here while every other service kept them"
+        );
+        assert!(resolve_prepared_statements_from_pairs(&[(
+            "FLUXER_POSTGRES_PREPARED_STATEMENTS",
+            "   ",
+        )]));
+    }
+
+    #[test]
+    fn an_explicit_prepared_statements_value_is_honoured() {
+        assert!(!resolve_prepared_statements_from_pairs(&[(
+            "FLUXER_POSTGRES_PREPARED_STATEMENTS",
+            "false",
+        )]));
+        assert!(!resolve_prepared_statements_from_pairs(&[(
+            "FLUXER_POSTGRES_PREPARED_STATEMENTS",
+            "OFF",
+        )]));
+        assert!(resolve_prepared_statements_from_pairs(&[(
+            "FLUXER_POSTGRES_PREPARED_STATEMENTS",
+            "yes",
+        )]));
+    }
+
+    #[test]
+    fn a_non_boolean_prepared_statements_value_keeps_the_shared_default() {
+        assert!(resolve_prepared_statements_from_pairs(&[(
+            "FLUXER_POSTGRES_PREPARED_STATEMENTS",
+            "maybe",
+        )]));
+    }
+
     #[test]
     fn time_freeze_enabled_by_default_for_hosted_runtime() {
         assert!(resolve_time_freeze_from_pairs(&[]));