Struct PhotonBuilder 

pub struct PhotonBuilder { /* private fields */ }

Builder for constructing Photon runtimes.

Wire a StoragePort (or accept the default in-process port), optionally install inventory discovery and ops telemetry, then build. Keep the returned Photon handle for publish_on / subscribe_on.

Mode	Typical wiring
Mode 1 — Embedded	Default builder, or storage_port with SQLite
Mode 2 — Brokered	storage_port with NATS/Kafka/Fluvio on every binary

Getting started: Mode 1, Mode 2.

Examples

Default mem path (loads PHOTON_TRANSPORT_KEY via TransportCrypto::from_env):

use photon_runtime::Photon;

let _photon = Photon::builder().auto_registry().build()?;

Explicit storage port:

use std::sync::Arc;

use photon_backend::{InProcStoragePort, StoragePort, TransportCrypto};
use photon_runtime::Photon;

let port: Arc<dyn StoragePort> = Arc::new(InProcStoragePort::new(
    TransportCrypto::from_env()?,
));
let _photon = Photon::builder().storage_port(port).auto_registry().build()?;

Implementations

impl PhotonBuilder

pub fn storage_port(self, port: Arc<dyn StoragePort>) -> Self

Explicit storage port (defaults to in-process mem via InProcStoragePort).

Use this for SQLite (Mode 1 durable) and for broker adapters (Mode 2 — same port config on publisher and worker). See Getting started → Mode 2.

Example

use std::sync::Arc;

use photon_backend::{InProcStoragePort, StoragePort, TransportCrypto};
use photon_runtime::Photon;

let port: Arc<dyn StoragePort> = Arc::new(InProcStoragePort::new(
    TransportCrypto::from_env()?,
));
let _photon = Photon::builder().storage_port(port).auto_registry().build()?;

pub fn backend(self, backend: Arc<dyn PhotonBackend>) -> Self

Pre-built backend instance.

Prefer storage_port for normal hosts. Use this when you already constructed a PhotonBackend (tests, custom delivery stacks).

Errors

build returns an error if both this and backend_with_context are set.

pub fn backend_with_context<F>(self, install: F) -> Self

where F: FnOnce(BackendContext) -> Result<Arc<dyn PhotonBackend>> + Send + 'static,

Build backend from shared BackendContext (custom install closures).

Prefer storage_port for adapter wiring. This is for hosts that install a custom PhotonBackend from the registry context.

Example

use std::sync::Arc;

use photon_backend::{BackendContext, EmbeddedBackend};
use photon_runtime::Photon;

let _photon = Photon::builder()
    .backend_with_context(|ctx: BackendContext| EmbeddedBackend::install_mem(ctx))
    .auto_registry()
    .build()?;

pub fn mem_backend(self) -> Self

Shorthand for backend_with_context with EmbeddedBackend::install_mem.

Equivalent to the default path when you also omit storage_port (in-process mem). Prefer the default build unless you need an explicit install fn.

Example

use photon_runtime::Photon;

let _photon = Photon::builder().mem_backend().auto_registry().build()?;

pub fn ops_log(self, log: impl OpsLog + 'static) -> Self

Install a concrete OpsLog adapter before build.

Runnable: cargo run -p uf-photon --example telemetry_ops_log --features runtime,mem.

Example

use photon_runtime::Photon;
use photon_telemetry::ConsoleOpsLog;

let _photon = Photon::builder()
    .ops_log(ConsoleOpsLog)
    .auto_registry()
    .build()?;

pub fn ops_log_arc(self, log: Arc<dyn OpsLog>) -> Self

Install a shared OpsLog trait object before build.

pub const fn auto_registry(self) -> Self

Discover #[photon::topic] / #[photon::subscribe] descriptors via Quark inventory.

Required when using the macros in the same crate graph as the host. Without this, the topic registry stays empty and the executor has nothing to dispatch.

Runnable: cargo run -p uf-photon --example embedded_mem --features runtime,mem.

pub fn retention_policy(self, policy: RetentionPolicy) -> Self

Override default retention policy (env fallbacks apply for unset fields).

pub fn retention_hook(self, hook: Arc<dyn RetentionHook>) -> Self

Host hook for extra subscriptions and legal-hold floors.

pub fn build(self) -> Result<Photon>

Assemble the Photon runtime.

Defaults

• Storage port: InProcStoragePort with TransportCrypto::from_env when storage_port was not set — requires PHOTON_TRANSPORT_KEY
• Backend: generic backend over that port when no custom backend / backend_with_context is set
• Registry: empty unless auto_registry was called

Errors

Returns an error if transport crypto cannot load from the environment, a custom install fn fails, or both backend and backend_with_context were set.

Trait Implementations

impl Default for PhotonBuilder

fn default() -> PhotonBuilder

Returns the “default value” for a type.