Interface ResourceQuery

src/common/resourceiterator.rs:30–57

/// This is a low-level trait that should not be used directly.
#[async_trait]
pub trait ResourceQuery {
    /// Item type.
    type Item;

    /// Default limit to use with this query.
    const DEFAULT_LIMIT: usize;

    /// Whether pagination is supported for this query.
    async fn can_paginate(&self) -> Result<bool>;

    /// Extract a marker from a resource.
    fn extract_marker(&self, resource: &Self::Item) -> String;

    /// Get a chunk of resources.
    async fn fetch_chunk(
        &self,
        limit: Option<usize>,
        marker: Option<String>,
    ) -> Result<Vec<Self::Item>>;

    /// Validate the query before the first execution.
    ///
    /// This call may modify internal representation of the query, so changing
    /// the query after calling it may cause undesired side effects.
    async fn validate(&mut self) -> Result<()> {
        Ok(())
    }
}

/// Generic iterator over resources.
#[derive(Debug, Clone)]