Struct Expression

pub struct Expression {
    pub condition_expression: Option<String>,
    pub key_condition_expression: Option<String>,
    pub update_expression: Option<String>,
    pub filter_expression: Option<String>,
    pub projection_expression: Option<String>,
    pub expression_attribute_names: Option<HashMap<String, String>>,
    pub expression_attribute_values: Option<HashMap<String, AttributeValue>>,
}

The data needed for various aws_sdk_dynamodb input types.

Use Builder (via Expression::builder) to create DynamoDB condition, filter, projection, key condition, and update expressions.

You can use these methods to consume this and set up a DynamoDB operation. See their docs for examples.

• .put_item()
• .get_item()
• .scan()
• .query()
• .update_item()
• .delete_item()

See also the to_*_input_builder and to_*_fluent_builder methods for populating aws_sdk_dynamodb types.

You can use the fields on this struct to manually populate an aws_sdk_dynamodb input type, or you can use one of the many methods on this to automatically build or populate one of those types.

Fields

condition_expression: Option<String>

The string to use as a DynamoDB condition expression.

Be sure to also use .expression_attribute_names and .expression_attribute_values.

key_condition_expression: Option<String>

The string to use use as a DynamoDB key condition expression.

Be sure to also use .expression_attribute_names and .expression_attribute_values.

update_expression: Option<String>

The string to use as a DynamoDB update expression.

Be sure to also use .expression_attribute_names and .expression_attribute_values.

filter_expression: Option<String>

The string to use as a DynamoDB filter expression.

Be sure to also use .expression_attribute_names and .expression_attribute_values.

projection_expression: Option<String>

The string to use as a DynamoDB projection expression.

Be sure to also use .expression_attribute_names.

expression_attribute_names: Option<HashMap<String, String>>

DynamoDB expression attribute names.

expression_attribute_values: Option<HashMap<String, AttributeValue>>

DynamoDB expression attribute values.

Implementations

impl Expression

Methods related to PutItem operations.

pub fn to_put_builder(self) -> PutBuilder

Uses this Expression to create a PutBuilder with the following set:

• Condition expression
• Expression attribute names
• Expression attribute values

pub fn to_put_item_input_builder(self) -> PutItemInputBuilder

Uses this Expression to set the following on a PutItemInputBuilder:

• Condition expression
• Expression attribute names
• Expression attribute values

pub fn to_put_item_fluent_builder( self, builder: PutItemFluentBuilder, ) -> PutItemFluentBuilder

Uses this Expression to set the following on a PutItemFluentBuilder before returning it:

• Condition expression
• Expression attribute names
• Expression attribute values

pub fn put_item(self, client: &Client) -> PutItemFluentBuilder

Sets up a put_item using the provided Client and uses this Expression to set the following on the PutItemFluentBuilder before returning it:

• Condition expression
• Expression attribute names
• Expression attribute values

Example

use aws_config::BehaviorVersion;
use aws_sdk_dynamodb::{types::AttributeValue, Client};
use dynamodb_expression::{Expression, Path};

let client = Client::new(&aws_config::load_defaults(BehaviorVersion::latest()).await);

let output = Expression::builder()
    .with_condition("name".parse::<Path>()?.attribute_not_exists())
    .build()
    .put_item(&client)
    .table_name("people")
    .item("name", AttributeValue::S(String::from("Jill")))
    .item("age", AttributeValue::N(40.to_string()))
    .send()
    .await?;

impl Expression

Methods related to GetItem operations.

pub fn to_get_builder(self) -> GetBuilder

Uses this Expression to create a GetBuilder with the following set:

• Projection expression
• Expression attribute names

pub fn to_get_item_input_builder(self) -> GetItemInputBuilder

Uses this Expression to set the following on a GetItemInputBuilder:

• Projection expression
• Expression attribute names

pub fn to_get_item_fluent_builder( self, builder: GetItemFluentBuilder, ) -> GetItemFluentBuilder

Uses this Expression to set the following on a GetItemFluentBuilder before returning it:

• Projection expression
• Expression attribute names

pub fn get_item(self, client: &Client) -> GetItemFluentBuilder

Sets up a get_item using the provided Client and uses this Expression to set the following on the GetItemFluentBuilder before returning it:

• Projection expression
• Expression attribute names

Example

use aws_config::BehaviorVersion;
use aws_sdk_dynamodb::{types::AttributeValue, Client};
use dynamodb_expression::Expression;

let client = Client::new(&aws_config::load_defaults(BehaviorVersion::latest()).await);

let output = Expression::builder()
    .with_projection(["name", "age"])
    .build()
    .get_item(&client)
    .table_name("people")
    .key("id", AttributeValue::N(42.to_string()))
    .send()
    .await?;

impl Expression

Methods related to UpdateItem operations.

pub fn to_update_builder(self) -> UpdateBuilder

Uses this Expression to create an UpdateBuilder with the following set:

• Update expression
• Condition expression
• Expression attribute names
• Expression attribute values

pub fn to_update_item_input_builder(self) -> UpdateItemInputBuilder

Uses this Expression to create an UpdateItemInputBuilder with the following set:

• Update expression
• Condition expression
• Expression attribute names
• Expression attribute values

pub fn to_update_item_fluent_builder( self, builder: UpdateItemFluentBuilder, ) -> UpdateItemFluentBuilder

Uses this Expression to set the following on an UpdateItemFluentBuilder before returning it:

• Update expression
• Condition expression
• Expression attribute names
• Expression attribute values

pub fn update_item(self, client: &Client) -> UpdateItemFluentBuilder

Sets up an update_item using the provided Client and uses this Expression to set the following on the UpdateItemFluentBuilder before returning it:

• Update expression
• Condition expression
• Expression attribute names
• Expression attribute values

Example

use aws_config::BehaviorVersion;
use aws_sdk_dynamodb::{types::AttributeValue, Client};
use dynamodb_expression::{Expression, Num, Path};

let client = Client::new(&aws_config::load_defaults(BehaviorVersion::latest()).await);

let age: Path = "age".parse()?;
let output = Expression::builder()
    .with_condition(age.clone().equal(Num::new(40)))
    .with_update(age.math().add(1))
    .build()
    .update_item(&client)
    .table_name("people")
    .key("name", AttributeValue::S(String::from("Jack")))
    .send()
    .await?;

impl Expression

Methods related to DeleteItem operations.

pub fn to_delete_builder(self) -> DeleteBuilder

Uses this Expression to create a DeleteBuilder with the following set:

• Condition expression
• Expression attribute names
• Expression attribute values

pub fn to_delete_item_input_builder(self) -> DeleteItemInputBuilder

Uses this Expression to set the following on a DeleteItemInputBuilder:

• Condition expression
• Expression attribute names
• Expression attribute values

pub fn to_delete_item_fluent_builder( self, builder: DeleteItemFluentBuilder, ) -> DeleteItemFluentBuilder

Uses this Expression to set the following on a DeleteItemFluentBuilder before returning it:

• Condition expression
• Expression attribute names
• Expression attribute values

pub fn delete_item(self, client: &Client) -> DeleteItemFluentBuilder

Sets up a delete_item using the provided Client and uses this Expression to set the following on the DeleteItemFluentBuilder before returning it:

• Condition expression
• Expression attribute names
• Expression attribute values

Example

use aws_config::BehaviorVersion;
use aws_sdk_dynamodb::{types::AttributeValue, Client};
use dynamodb_expression::{Expression, Num, Path};

let client = Client::new(&aws_config::load_defaults(BehaviorVersion::latest()).await);

let output = Expression::builder()
    .with_condition("age".parse::<Path>()?.less_than(Num::new(20)))
    .build()
    .delete_item(&client)
    .table_name("people")
    .key("name", AttributeValue::S(String::from("Jack")))
    .send()
    .await?;

impl Expression

Methods related to Query operations.

pub fn to_query_input_builder(self) -> QueryInputBuilder

Uses this Expression to create a QueryInputBuilder with the following set:

• Key condition expression
• Filter expression
• Projection expression
• Expression attribute names
• Expression attribute values

pub fn to_query_fluent_builder( self, builder: QueryFluentBuilder, ) -> QueryFluentBuilder

Uses this Expression to set the following on a QueryFluentBuilder before returning it:

• Key condition expression
• Filter expression
• Projection expression
• Expression attribute names
• Expression attribute values

pub fn query(self, client: &Client) -> QueryFluentBuilder

Sets up a query using the provided Client and uses this Expression to set the following on the QueryFluentBuilder before returning it:

• Key condition expression
• Filter expression
• Projection expression
• Expression attribute names
• Expression attribute values

Example

use aws_config::BehaviorVersion;
use aws_sdk_dynamodb::Client;
use dynamodb_expression::{Expression, Num, Path};

let client = Client::new(&aws_config::load_defaults(BehaviorVersion::latest()).await);

let output = Expression::builder()
    .with_filter(
        "name"
            .parse::<Path>()?
            .attribute_exists()
            .and("age".parse::<Path>()?.greater_than_or_equal(Num::new(25))),
    )
    .with_projection(["name", "age"])
    .with_key_condition("id".parse::<Path>()?.key().equal(Num::new(42)))
    .build()
    .query(&client)
    .table_name("people")
    .send()
    .await?;

impl Expression

Methods related to Scan operations.

pub fn to_scan_input_builder(self) -> ScanInputBuilder

Uses this Expression to create a ScanInputBuilder with the following set:

• Filter expression
• Projection expression
• Expression attribute names
• Expression attribute values

pub fn to_scan_fluent_builder( self, builder: ScanFluentBuilder, ) -> ScanFluentBuilder

Uses this Expression to set the following on a ScanFluentBuilder before returning it:

• Filter expression
• Projection expression
• Expression attribute names
• Expression attribute values

pub fn scan(self, client: &Client) -> ScanFluentBuilder

Sets up a scan using the provided Client and uses this Expression to set the following on the ScanFluentBuilder before returning it:

• Filter expression
• Projection expression
• Expression attribute names
• Expression attribute values

Example

use aws_config::BehaviorVersion;
use aws_sdk_dynamodb::Client;
use dynamodb_expression::{Expression, Num, Path};

let client = Client::new(&aws_config::load_defaults(BehaviorVersion::latest()).await);

let output = Expression::builder()
    .with_filter("age".parse::<Path>()?.greater_than_or_equal(Num::new(25)))
    .with_projection(["name", "age"])
    .build()
    .scan(&client)
    .table_name("people")
    .send()
    .await?;

impl Expression

pub fn to_keys_and_attributes_builder(self) -> KeysAndAttributesBuilder

Uses this Expression to create a KeysAndAttributesBuilder with the following set:

• Projection expression
• Expression attribute names

Example

use std::collections::HashMap;

use aws_config::BehaviorVersion;
use aws_sdk_dynamodb::{types::AttributeValue, Client};
use dynamodb_expression::Expression;

let client = Client::new(&aws_config::load_defaults(BehaviorVersion::latest()).await);

let expression = Expression::builder()
    .with_projection(["name", "age"])
    .build();

let key = HashMap::from([("id".to_string(), AttributeValue::N(42.to_string()))]);

let output = client
    .batch_get_item()
    .request_items(
        "leads",
        expression
            .clone()
            .to_keys_and_attributes_builder()
            .keys(key.clone())
            .build()
            .unwrap(),
    )
    .request_items(
        "customers",
        expression
            .to_keys_and_attributes_builder()
            .keys(key)
            .build()
            .unwrap(),
    )
    .send()
    .await?;

pub fn to_condition_check_builder(self) -> ConditionCheckBuilder

Uses this Expression to create a ConditionCheckBuilder with the following set:

• Condition expression
• Expression attribute names
• Expression attribute values

impl Expression

pub fn builder() -> Builder

Trait Implementations

impl Clone for Expression

fn clone(&self) -> Expression

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Expression

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

Formats the value using the given formatter.

impl PartialEq for Expression

fn eq(&self, other: &Expression) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Expression