> For the complete documentation index, see [llms.txt](https://ecfmg.gitbook.io/azure-serverless-quickstart/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ecfmg.gitbook.io/azure-serverless-quickstart/patterns-and-practices/ddd/field-types/primitive-types.md).

# Primitive Types

Describes how to deal with primitive field types from Cosmos to Domain

Primitive type fields are a one-to-one copy from Cosmos DB model into the Domain props.

### Cosmos DB Model

{% code title="/infrastructure/data-sources/cosmos-db/models/physician.ts" %}

```typescript
lastName: string;
```

{% endcode %}

### Domain Props

{% code title="/domain/contexts/physician/physician.ts" %}

```typescript
lastName: string;
```

{% endcode %}

<figure><img src="https://689969976-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-MHqEwg1NK1prYWccTSJ%2Fuploads%2FjR5t0AT0ubTmg8GQhWJR%2FsideBySide.png?alt=media&amp;token=12a19f73-5725-4605-a15b-9a2fa2064de1" alt=""><figcaption><p>Domain Props on left, Cosmos DB Model on right</p></figcaption></figure>

* Don't need id field on Domain Props side because already defined in EntityProps
* Every field in domain props is required regardless of if it's optional on cosmos db side

### Domain Entity Reference

```typescript
export interface PhysicianEntityReference extends Readonly<PhysicianProps> {} 
```

* primitive types are copied automatically as read-only in entity reference&#x20;
* no need to omit primitive type fields from entity reference like you would for non-primitive type
* if domain object only has primitive types, entity reference should look exactly as above

### Domain Class

* Primitive fields require getter and setter methods in the domain class of the object

#### Getter

{% code title="/domain/contexts/physician/physician.ts" %}

```typescript
get lastName() {
    return this.props.lastName;
}
```

{% endcode %}

#### Setter

{% code title="/domain/contexts/physician/physician.ts" %}

```typescript
public requestSetLastName(lastName: string) {
    this.props.lastName = lastName;
}
```

{% endcode %}

### Domain Adapter

* Primitive fields require getter and setter methods in the domain adapter of the object

#### Getter

{% code title="/domain/infrastructure/persistence/physician.domain-adapter.ts" %}

```typescript
get lastName() {
    return this.doc.lastName;
}
```

{% endcode %}

#### Setter

{% code title="/domain/infrastructure/persistence/physician.domain-adapter.ts" %}

```typescript
set lastName(lastName) {
    this.doc.lastName = lastName;
}
```

{% endcode %}