Struct QueryParams 

pub struct QueryParams {
    pub page: usize,
    pub limit: usize,
    pub filter: Option<String>,
    pub sort: Option<String>,
}

Query parameters for pagination and filtering

This structure is used to extract pagination and filtering parameters from URL query strings. All parameters have sensible defaults.

Example

// In handler:
pub async fn list_items(
    Query(params): Query<QueryParams>,
) -> Json<PaginatedResponse<Item>> {
    // params.page defaults to 1
    // params.limit defaults to 20
}

// Usage:
GET /items?page=2&limit=10
GET /items?filter={"status": "active"}
GET /items?page=1&limit=20&filter={"amount>": 100}&sort=created_at:desc

Fields

page: usize

Page number (starts at 1)

limit: usize

Number of items per page

filter: Option<String>

Filters as JSON object

Format

• Exact match: {"field": "value"}
• Comparison: {"field>": value, "field<": value, "field>=": value, "field<=": value}

Example

filter={"status": "active", "amount>": 100, "customer_name": "Acme"}

sort: Option<String>

Sort field and direction

Format

• field:asc or field (ascending)
• field:desc (descending)

Example

sort=amount:desc
sort=created_at:asc

Implementations

impl QueryParams

pub fn page(&self) -> usize

Get page number, ensuring minimum of 1

pub fn limit(&self) -> usize

Get limit, ensuring it doesn’t exceed the maximum

pub fn filter_value(&self) -> Option<Value>

Parse filter JSON string into Value

Trait Implementations

impl Clone for QueryParams

fn clone(&self) -> QueryParams

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for QueryParams

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

Formats the value using the given formatter.

impl Default for QueryParams

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for QueryParams

where QueryParams: Default,

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.