Struct Key 

pub struct Key<TD: TableDefinition>(/* private fields */);

A type-safe wrapper for a DynamoDB key belonging to a specific table.

Key<TD> holds only the key attributes (PK, and SK for composite-key tables) for the table defined by the TableDefinition TD.

A Key can only be obtain from a type implementing KeyBuilder — typically any DynamoDBItem — or by extracting it from an Item.

Examples

Building a key from a KeyBuilder:

use dynamodb_facade::{DynamoDBItem, Key, KeyBuilder};

fn platform_key<KB: KeyBuilder<PlatformTable>>(key_builder: &KB) -> Key<PlatformTable> {
    key_builder.get_key()
}

// User implements KeyBuilder<PlatformTable> because it is a DynamoDBItem<PlatformTable>
let user = sample_user();
let key = platform_key(&user);

let raw = key.into_inner();
assert_eq!(
    raw["PK"].as_s().unwrap(),
    "USER#user-1"
);

Extracting a key from an item:

use dynamodb_facade::DynamoDBItem;

let item = sample_user().to_item();
let key = item.into_key_only();
let raw = key.into_inner();

assert!(raw.contains_key("PK"));
assert!(raw.contains_key("SK"));
assert!(!raw.contains_key("name")); // payload stripped

Implementations

impl<TD: TableDefinition> Key<TD>

pub fn into_inner(self) -> HashMap<String, AttributeValue>

Consumes the key and returns the underlying raw attribute map.

The map contains only the key attributes (PK and SK for composite-key tables). Use this when you need to pass the key to raw SDK builders.

Examples

use dynamodb_facade::{DynamoDBItem, Key, KeyBuilder};

let key: Key<PlatformTable> = sample_user().get_key();
let raw = key.into_inner();
assert_eq!(raw["PK"].as_s().unwrap(), "USER#user-1");
assert_eq!(raw["SK"].as_s().unwrap(), "USER");

Trait Implementations

impl<TD: TableDefinition> Debug for Key<TD>

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

Formats the value using the given formatter.

impl<TD: TableDefinition> From<Key<TD>> for Item<TD>

fn from(value: Key<TD>) -> Self

Converts to this type from the input type.