A DynamoDB abstraction for Rust
Deez is a DynamoDB abstraction for implementing Single Table Design easily,
inspired by ElectroDB.
Getting Started
Define a schema for your entities using the Deez
procedural macro. Doing so
will derive the From
conversion traits for your structs and the
HashMap<String, AttributeValue>
type used by the aws_sdk_dynamodb
library,
with some additional features for facilitating Single Table Design.
use aws_sdk_dynamodb::types::AttributeValue;
use deez::*;
use std::collections::HashMap;
use uuid::Uuid;
#[derive(Debug, Clone, Deez)]
#[deez_schema(table = "TaskTable", service = "TaskService", entity = "Task")]
#[deez_schema(primary_hash = "pk", primary_range = "sk")]
#[deez_schema(gsi1_name = "gsi1", gsi1_hash = "gsi1pk", gsi1_range = "gsi1sk")]
#[deez_schema(gsi2_name = "gsi2", gsi2_hash = "gsi2pk", gsi2_range = "gsi2sk")]
pub struct Task {
#[deez_primary(key = "hash")]
#[deez_gsi1(key = "range", position = 1)]
#[deez_gsi2(key = "range", position = 1)]
pub task_id: Option<String>,
#[deez_primary(key = "range", position = 1)]
#[deez_gsi1(key = "hash")]
#[deez_gsi2(key = "range")]
pub project: Option<String>,
#[deez_primary(key = "range")]
#[deez_gsi1(key = "range")]
#[deez_gsi2(key = "hash")]
pub employee: Option<String>,
pub description: String,
#[deez_ignore(ignore)]
pub some_metadata: String,
}
impl Default for Task {
fn default() -> Self {
Task {
task_id: Some(Uuid::new_v4().to_string()),
project: Some("".to_string()),
employee: Some("".to_string()),
description: "".to_string(),
some_metadata: "".to_string(),
}
}
}
Now you can convert your struct to a HashMap
that you can pass directly to the
DynamoDB client.
let task = Task {
project: Some("foo_project".to_string()),
employee: Some("e42069".to_string()),
description: "nothin' but chillin' 20's".to_string(),
some_metadata: "baz".to_string(),
..Default::default()
};
let map: HashMap<String, AttributeValue> = task.into();
println!("{:#?}", map);
The following example shows a practical use-case interacting with DynamoDB
client:
use anyhow::Result;
use aws_sdk_dynamodb::Client;
#[tokio::main]
async fn main() -> Result<()> {
let client = Client::new(
&aws_config::from_env()
.endpoint_url("http://localhost:8000")
.region("us-east-1")
.load()
.await,
);
create!(
client;
Task {
project: Some("foo_project".to_string()),
employee: Some("e42069".to_string()),
description: "nothin' but chillin' 20's".to_string(),
some_metadata: "baz".to_string(),
..Default::default()
}
)?;
let keys = Task {
task_id: Some("1a2b3c4d".to_string()),
project: Some("foo_project".to_string()),
employee: Some("e42069".to_string()),
..Default::default()
}
.primary_keys();
let tasks = vec_from_query!(
client
.query()
.table_name(Task::table_name())
.key_condition_expression("#pk = :pk and begins_with(#sk, :sk)")
.set_expression_attribute_names(Some(HashMap::from([
("#pk".to_string(), keys.hash.field()),
("#sk".to_string(), keys.range.field()),
])))
.set_expression_attribute_values(Some(HashMap::from([
(":pk".to_string(), keys.hash.av()),
(":sk".to_string(), keys.range.av()),
])))
.send()
.await?
=> TaskItems
);
Ok(())
}