Struct ProxyConfig 

pub struct ProxyConfig {

    pub listen_address: String,
    pub admin_address: String,
    pub admin_token: Option<String>,
    pub tr_enabled: bool,
    pub tr_mode: TrMode,
    pub pool: PoolConfig,
    pub pool_mode: PoolModeConfig,
    pub load_balancer: LoadBalancerConfig,
    pub health: HealthConfig,
    pub nodes: Vec<NodeConfig>,
    pub tls: Option<TlsConfig>,
    pub write_timeout_secs: u64,
    pub plugins: PluginToml,
    pub hba: Vec<HbaRule>,
    pub auth: AuthConfig,
    pub mcp: McpConfig,
    pub agent_contracts: Vec<AgentContract>,
    pub http_gateway: HttpGatewayConfig,
    pub mirror: MirrorConfig,
    pub branch: BranchConfig,
    pub routing_hints: RoutingHintsConfig,
    pub rate_limit: RateLimitToml,
    pub circuit_breaker: CircuitBreakerToml,
    pub analytics: AnalyticsToml,
    pub lag_routing: LagRoutingToml,
    pub cache: CacheToml,
    pub query_rewrite: QueryRewriteToml,
    pub multi_tenancy: MultiTenancyToml,
    pub schema_routing: SchemaRoutingToml,
    pub graphql_gateway: GraphqlGatewayConfig,
    pub optimize_unnamed_parse: bool,
    pub shutdown_drain_timeout_secs: u64,
}

Proxy configuration

Fields

listen_address: String

Listen address for client connections

admin_address: String

Admin API address

admin_token: Option<String>

Bearer token required on admin API requests. When set, every admin endpoint except liveness probes (/health*, /livez, /readyz) requires Authorization: Bearer <token>. Absent (default) = open (current behaviour) — set this for any non-loopback deployment.

tr_enabled: bool

Enable TR (Transaction Replay)

tr_mode: TrMode

TR mode

pool: PoolConfig

Connection pool configuration

pool_mode: PoolModeConfig

Pool mode configuration (Session/Transaction/Statement)

load_balancer: LoadBalancerConfig

Load balancer configuration

health: HealthConfig

Health check configuration

nodes: Vec<NodeConfig>

Backend nodes

tls: Option<TlsConfig>

TLS configuration

write_timeout_secs: u64

Write timeout during failover (seconds) When primary is unavailable, wait this long for a new primary before returning error

plugins: PluginToml

Plugin system configuration. Only consumed when the wasm-plugins feature is enabled; on a feature-off build, values are parsed and ignored so existing configs don’t break.

hba: Vec<HbaRule>

pg_hba-style connection admission rules, evaluated in order before any backend connection is opened. Empty (the default) means admit all (current behaviour preserved).

auth: AuthConfig

Client authentication mode. Absent/default = pass-through (the proxy relays the client’s auth to the backend, current behaviour).

mcp: McpConfig

MCP (Model Context Protocol) agent gateway. Disabled by default.

agent_contracts: Vec<AgentContract>

Per-agent SQL contracts (scoped grants). Referenced by id from the MCP gateway ([mcp] contract). Empty by default.

http_gateway: HttpGatewayConfig

HTTP SQL gateway (Neon-serverless-driver compatible). Disabled by default — lets edge/serverless clients run SQL over HTTP.

mirror: MirrorConfig

Continuous traffic mirroring to a secondary backend. Disabled by default — the on-ramp to a PG->Nano migration mirror.

branch: BranchConfig

Instant branch databases. Disabled by default — provisions CREATE DATABASE … TEMPLATE clones through the proxy.

routing_hints: RoutingHintsConfig

SQL-comment routing hints (/*helios:route=primary*/). Disabled by default — when enabled, the proxy parses hints from query SQL and applies them as a route override that wins over the default verb routing (but never over a plugin Block). Only consumed when the routing-hints feature is compiled in; parsed-and-ignored otherwise.

rate_limit: RateLimitToml

Multi-dimensional rate limiting (token bucket + concurrency). Disabled by default. Only enforced when the rate-limiting feature is compiled in; parsed-and-ignored otherwise.

circuit_breaker: CircuitBreakerToml

Per-node circuit breaker (trip failing backends out of rotation, fast-fail while open). Disabled by default. Only enforced when the circuit-breaker feature is compiled in.

analytics: AnalyticsToml

Query analytics (fingerprinting, per-query statistics, slow-query log, pattern detection). Disabled by default. Only active when the query-analytics feature is compiled in.

lag_routing: LagRoutingToml

Replica-lag-aware routing + read-your-writes. Disabled by default. Only enforced when the lag-routing feature is compiled in.

cache: CacheToml

Query-result cache (L1 hot / L2 warm). Disabled by default. Only active when the query-cache feature is compiled in.

query_rewrite: QueryRewriteToml

SQL query rewriting (rules engine). Disabled by default. Only active when the query-rewriting feature is compiled in.

multi_tenancy: MultiTenancyToml

Multi-tenancy (per-tenant row isolation via injected predicates). Disabled by default. Only active when the multi-tenancy feature is compiled in.

schema_routing: SchemaRoutingToml

Schema/workload-aware routing (route OLAP queries to an analytics node). Disabled by default. Only active when the schema-routing feature is on.

graphql_gateway: GraphqlGatewayConfig

GraphQL-to-SQL gateway (separate HTTP listener). Disabled by default. Only active when the graphql-gateway feature is compiled in.

optimize_unnamed_parse: bool

Proxy-side unnamed-Parse promotion (Batch H). When a client re-sends an identical unnamed extended Parse (the dominant pgbench/ORM pattern), the proxy skips forwarding it to a backend that already holds that exact unnamed statement and synthesizes the ParseComplete locally — cutting the per-cycle re-Parse overhead. Default on; a kill-switch for drivers that somehow depend on the redundant round trip.

shutdown_drain_timeout_secs: u64

How long a graceful binary-handoff drain (SIGUSR2) keeps serving in-flight connections before the old process exits (Batch H). After this many seconds, any still-open connections are dropped so the handoff completes in bounded time. Overridable at runtime via the HELIOS_DRAIN_TIMEOUT_SECS env var.

Implementations

impl ProxyConfig

pub fn write_timeout(&self) -> Duration

Get write timeout as Duration

pub fn from_file(path: &str) -> Result<Self>

Load configuration from file

pub fn add_node(&mut self, host_port: &str, role: &str) -> Result<()>

Add a node from host:port string

pub fn validate(&self) -> Result<()>

Validate configuration

pub fn primary_node(&self) -> Option<&NodeConfig>

Get primary node

pub fn standby_nodes(&self) -> Vec<&NodeConfig>

Get standby nodes

pub fn enabled_nodes(&self) -> Vec<&NodeConfig>

Get all enabled nodes

Trait Implementations

impl Clone for ProxyConfig

fn clone(&self) -> ProxyConfig

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ProxyConfig

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ProxyConfig

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for ProxyConfig

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for ProxyConfig

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.