azure_data_cosmos_driver 0.2.0

Core implementation layer for Azure Cosmos DB - provides transport, routing, and protocol handling for cross-language SDK reuse
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// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.

//! Account-level endpoint routing state.

use std::{collections::HashMap, sync::Arc, time::Instant};

use url::Url;

use super::{CosmosEndpoint, UnavailableReason};

/// Immutable account-level endpoint routing state.
#[derive(Clone, Debug)]
pub(crate) struct AccountEndpointState {
    /// Monotonically increasing generation for stale index detection.
    pub generation: u64,
    /// Ordered preferred read endpoints.
    pub preferred_read_endpoints: Arc<[CosmosEndpoint]>,
    /// Ordered preferred write endpoints.
    pub preferred_write_endpoints: Arc<[CosmosEndpoint]>,
    /// Endpoints marked temporarily unavailable, keyed by their primary URL.
    pub unavailable_endpoints: HashMap<Url, (Instant, UnavailableReason)>,
    /// Whether account supports multiple write locations.
    pub multiple_write_locations_enabled: bool,
    /// Fallback endpoint when no preferred endpoint is available.
    pub default_endpoint: CosmosEndpoint,
}

impl AccountEndpointState {
    /// Creates a minimal single-endpoint state.
    pub fn single(default_endpoint: CosmosEndpoint) -> Self {
        Self {
            generation: 0,
            preferred_read_endpoints: vec![default_endpoint.clone()].into(),
            preferred_write_endpoints: vec![default_endpoint.clone()].into(),
            unavailable_endpoints: HashMap::new(),
            multiple_write_locations_enabled: false,
            default_endpoint,
        }
    }

    /// Returns preferred endpoints for the given operation kind.
    pub fn preferred_endpoints(&self, read_only: bool) -> &[CosmosEndpoint] {
        if read_only {
            &self.preferred_read_endpoints
        } else {
            &self.preferred_write_endpoints
        }
    }
}