# Resource Lifecycle

Each operation on a resource follows a well-defined lifecycle.\
This flow ensures clear separation of concerns between reading data, applying business logic, and producing the final response.

{% @mermaid/diagram content="flowchart TD
A\[Request] --> B\[Routing & Metadata]
B --> C\[Provider]
C --> D\[Processor]
D --> E\[Responder]
E --> F\[Response]

```
subgraph ProviderPhase [Provider Phase]
    direction LR
    C1[Load existing resource]
    C2[Create new instance]
    C3[Hydrate resource from request]
    C4[Validate resource]
end

subgraph ProcessorPhase [Processor Phase]
    direction LR
    D1[Apply business logic]
    D2[Persist resource]
    D3[Dispatch domain events]
end

subgraph ResponderPhase [Responder Phase]
    direction LR
    E1[Render template or redirect]
    E2[Return HTTP response]
end

C --> ProviderPhase
D --> ProcessorPhase
E --> ResponderPhase

style ProviderPhase fill:#f4f8ff,stroke:#93c5fd,stroke-width:1px
style ProcessorPhase fill:#fef9c3,stroke:#facc15,stroke-width:1px
style ResponderPhase fill:#fef2f2,stroke:#f87171,stroke-width:1px" %}
```

## Step-by-step explanation

### Routing & Metadata

The request is matched to a `Resource` and an `Operation` using metadata collected from attributes (eg `#[AsResource]`).\
This step defines which provider, processor, and responder should handle the request.

### Provider Phase

The provider is responsible for loading or creating the resource object, hydrating it from the request, and validating it before any business logic is applied.

**Example:** load from Doctrine, create a new instance, populate from request data, validate, or fetch from an external API.

### Processor Phase

The processor applies the business logic of the operation.

**Example:** persist the entity, execute domain services, or dispatch events.

You can use the default Doctrine processor, or implement your own for DDD use cases.

### Responder Phase

The responder produces the final output — it can render a Twig template or redirect to another route.


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