litellm-rs 0.6.0

A high-performance AI Gateway written in Rust, providing OpenAI-compatible APIs with intelligent routing, load balancing, and enterprise features
Documentation
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//! Execution flow tests

#![allow(deprecated)]

use super::router_tests::create_test_deployment;
use crate::core::providers::bedrock::BedrockErrorMapper;
use crate::core::providers::unified_provider::ProviderError;
use crate::core::router::RetrySchedule;
use crate::core::router::config::{RouterConfig, RoutingStrategy};
use crate::core::router::error::RouterError;
use crate::core::router::execution::is_retryable_error;
use crate::core::router::fallback::{ExecutionResult, FallbackConfig};
use crate::core::router::unified::Router;
use crate::core::types::model::ProviderCapability;
use std::sync::atomic::Ordering;

#[test]
fn test_is_retryable_error() {
    assert!(is_retryable_error(&ProviderError::rate_limit(
        "test",
        Some(60)
    )));
    assert!(is_retryable_error(&ProviderError::timeout(
        "test",
        "Request timed out"
    )));
    assert!(is_retryable_error(&ProviderError::network(
        "test",
        "Connection failed"
    )));
    assert!(is_retryable_error(&ProviderError::ProviderUnavailable {
        provider: "test",
        message: "Service unavailable".to_string(),
    }));
    let not_ready =
        BedrockErrorMapper::map_service_error("ModelNotReadyException", "model not ready")
            .expect("modeled Bedrock service error");
    assert!(is_retryable_error(&not_ready));
    assert!(!is_retryable_error(&ProviderError::api_error(
        "bedrock",
        424,
        "ModelNotReadyException: misleading ordinary HTTP message"
    )));
    assert!(!is_retryable_error(&ProviderError::api_error(
        "bedrock",
        404,
        "resource not found"
    )));
    assert!(!is_retryable_error(&ProviderError::api_error(
        "custom_httpx",
        424,
        "failed dependency"
    )));

    assert!(!is_retryable_error(&ProviderError::authentication(
        "test",
        "Invalid API key"
    )));
    assert!(!is_retryable_error(&ProviderError::model_not_found(
        "test", "gpt-5"
    )));
    assert!(!is_retryable_error(&ProviderError::invalid_request(
        "test",
        "Bad request"
    )));
    assert!(is_retryable_error(&ProviderError::quota_exceeded(
        "budget",
        "provider 'openai' budget exceeded"
    )));
    assert!(!is_retryable_error(&ProviderError::quota_exceeded(
        "budget",
        "budget exceeded for provider 'openai' model 'gpt-4o'"
    )));
    assert!(is_retryable_error(&ProviderError::quota_exceeded(
        "budget",
        "model 'gpt-4o' budget exceeded"
    )));
    assert!(!is_retryable_error(&ProviderError::quota_exceeded(
        "openai",
        "account quota exceeded"
    )));
}

#[tokio::test]
async fn test_execute_once_success() {
    let router = Router::default();
    let deployment = create_test_deployment("test-1", "gpt-4").await;
    router.add_deployment(deployment);

    let result = router
        .execute_once("gpt-4", |_deployment_id| async move {
            Ok(("success".to_string(), 100u64))
        })
        .await;

    assert!(result.is_ok());
    let exec_result = result.unwrap();
    assert_eq!(exec_result.result, "success");
    assert_eq!(exec_result.attempts, 1);
    assert!(!exec_result.used_fallback);
    assert!(exec_result.latency_us > 0);
}

#[tokio::test]
async fn test_execute_once_with_selected_deployment_keeps_snapshot_after_same_id_swap() {
    let router = std::sync::Arc::new(Router::default());
    let deployment = create_test_deployment("same-id", "gpt-4").await;
    router.add_deployment(deployment);

    let router_for_operation = router.clone();
    let result = router
        .execute_once_with_selected_deployment("gpt-4", move |deployment| {
            let router = router_for_operation.clone();
            async move {
                let selected_model = deployment.model.clone();
                let mut replacement = create_test_deployment("same-id", "gpt-4").await;
                replacement.model = "replacement-model".to_string();
                router.set_model_list(vec![replacement]);
                let current_model = router.get_deployment("same-id").unwrap().model.clone();
                Ok(((selected_model, current_model), 100u64))
            }
        })
        .await
        .unwrap();

    assert_eq!(result.result.0, "gpt-4-turbo");
    assert_eq!(result.result.1, "replacement-model");
    assert_eq!(result.deployment_id, "same-id");
    assert_eq!(result.model_used, "gpt-4-turbo");
    let current = router.get_deployment("same-id").unwrap();
    assert_eq!(current.state.total_requests.load(Ordering::Relaxed), 1);
}

#[tokio::test]
async fn test_execute_once_deployment_not_found() {
    let router = Router::default();

    let result = router
        .execute_once("gpt-4", |_deployment_id| async move {
            Ok(("success".to_string(), 100u64))
        })
        .await;

    assert!(result.is_err());
    let err = result.unwrap_err();
    assert!(matches!(err, RouterError::ModelNotFound(_)));
}

#[tokio::test]
async fn test_execute_once_operation_fails() {
    let router = Router::default();
    let deployment = create_test_deployment("test-1", "gpt-4").await;
    router.add_deployment(deployment);

    let result: Result<ExecutionResult<String>, _> = router
        .execute_once("gpt-4", |_deployment_id| async move {
            Err::<(String, u64), _>(ProviderError::authentication("test", "Invalid API key"))
        })
        .await;

    assert!(result.is_err());

    if let Some(d) = router.get_deployment("test-1") {
        assert_eq!(d.state.fail_requests.load(Ordering::Relaxed), 1);
    }
}

#[tokio::test]
async fn test_execute_with_retry_success_first_attempt() {
    let router = Router::default();
    let deployment = create_test_deployment("test-1", "gpt-4").await;
    router.add_deployment(deployment);

    let result = router
        .execute_with_retry("gpt-4", |_deployment_id| async move {
            Ok(("success".to_string(), 100u64))
        })
        .await;

    assert!(result.is_ok());
    let (value, deployment_id, attempts, _latency) = result.unwrap();
    assert_eq!(value, "success");
    assert_eq!(attempts, 1);
    assert_eq!(deployment_id, "test-1");
}

#[tokio::test]
async fn test_execute_with_retry_success_second_attempt() {
    let config = RouterConfig {
        num_retries: 3,
        retry_after_secs: 0,
        cooldown_time_secs: 0,
        ..Default::default()
    };
    let router = Router::new(config);
    let deployment = create_test_deployment("test-1", "gpt-4").await;
    router.add_deployment(deployment);

    let attempt_count = std::sync::Arc::new(std::sync::atomic::AtomicU32::new(0));
    let attempt_count_clone = attempt_count.clone();

    let result = router
        .execute_with_retry("gpt-4", move |_deployment_id| {
            let attempt_count = attempt_count_clone.clone();
            async move {
                let current = attempt_count.fetch_add(1, Ordering::Relaxed);
                if current == 0 {
                    Err(ProviderError::timeout("test", "Request timed out"))
                } else {
                    Ok(("success".to_string(), 100u64))
                }
            }
        })
        .await;

    assert!(result.is_ok());
    let (_value, _deployment_id, attempts, _latency) = result.unwrap();
    assert_eq!(attempts, 2);
}

fn one_millisecond_retry_schedule() -> RetrySchedule {
    RetrySchedule {
        base_delay_ms: 1,
        max_delay_ms: 1,
        backoff_multiplier: 2.0,
        jitter_ratio: 0.0,
    }
}

#[tokio::test]
async fn test_execute_with_retry_uses_selected_deployment_schedule() {
    let router = Router::new(RouterConfig {
        num_retries: 1,
        retry_after_secs: 30,
        ..Default::default()
    });
    let mut deployment = create_test_deployment("scheduled-retry", "gpt-4").await;
    deployment.config.retry_schedule = Some(one_millisecond_retry_schedule());
    router.add_deployment(deployment);
    let attempts = std::sync::Arc::new(std::sync::atomic::AtomicU32::new(0));

    let execution = router.execute_with_selected_deployment_retry("gpt-4", {
        let attempts = attempts.clone();
        move |_deployment| {
            let attempts = attempts.clone();
            async move {
                if attempts.fetch_add(1, Ordering::Relaxed) == 0 {
                    Err(ProviderError::timeout("test", "first attempt"))
                } else {
                    Ok(("success", 0))
                }
            }
        }
    });

    let result = tokio::time::timeout(std::time::Duration::from_secs(1), execution)
        .await
        .expect("deployment schedule should replace the 30-second router delay")
        .expect("second attempt should succeed");

    assert_eq!(result.0, "success");
    assert_eq!(result.2, 2);
}

#[tokio::test]
async fn test_execute_with_capability_retry_uses_selected_deployment_schedule() {
    let router = Router::new(RouterConfig {
        num_retries: 1,
        retry_after_secs: 30,
        ..Default::default()
    });
    let mut deployment = create_test_deployment("scheduled-capability-retry", "gpt-4").await;
    deployment.config.retry_schedule = Some(one_millisecond_retry_schedule());
    router.add_deployment(deployment);
    let attempts = std::sync::Arc::new(std::sync::atomic::AtomicU32::new(0));

    let execution = router.execute_with_selected_deployment_capability_retry(
        "gpt-4",
        &ProviderCapability::ChatCompletion,
        {
            let attempts = attempts.clone();
            move |_deployment| {
                let attempts = attempts.clone();
                async move {
                    if attempts.fetch_add(1, Ordering::Relaxed) == 0 {
                        Err(ProviderError::timeout("test", "first attempt"))
                    } else {
                        Ok(("success", 0))
                    }
                }
            }
        },
    );

    let result = tokio::time::timeout(std::time::Duration::from_secs(1), execution)
        .await
        .expect("deployment schedule should replace the 30-second router delay")
        .expect("second attempt should succeed");

    assert_eq!(result.0, "success");
    assert_eq!(result.2, 2);
}

#[tokio::test]
async fn test_execute_with_retry_excludes_model_budget_failures() {
    let config = RouterConfig {
        routing_strategy: RoutingStrategy::PriorityBased,
        num_retries: 1,
        retry_after_secs: 0,
        ..Default::default()
    };
    let router = Router::new(config);
    let mut primary = create_test_deployment("primary-model-budget", "shared").await;
    primary.model = "model-a".to_string();
    primary.config.priority = 0;
    let mut fallback = create_test_deployment("fallback-model-budget", "shared").await;
    fallback.model = "model-b".to_string();
    fallback.config.priority = 10;
    router.add_deployment(primary);
    router.add_deployment(fallback);
    let attempts = std::sync::Arc::new(std::sync::Mutex::new(Vec::new()));

    let result = router
        .execute_with_selected_deployment_retry("shared", {
            let attempts = attempts.clone();
            move |deployment| {
                let attempts = attempts.clone();
                async move {
                    attempts.lock().unwrap().push(deployment.model.clone());
                    if deployment.model == "model-a" {
                        Err(ProviderError::quota_exceeded(
                            "budget",
                            "model 'model-a' budget exceeded",
                        ))
                    } else {
                        Ok((deployment.id.clone(), 0))
                    }
                }
            }
        })
        .await
        .expect("fallback deployment should be selected after model budget miss");

    assert_eq!(result.0, "fallback-model-budget");
    assert_eq!(attempts.lock().unwrap().as_slice(), ["model-a", "model-b"]);
    let primary = router
        .get_deployment("primary-model-budget")
        .expect("primary deployment should exist");
    assert_eq!(primary.state.fail_requests.load(Ordering::Relaxed), 0);
}

async fn build_same_provider_budget_fallback_router(num_retries: u32) -> Router {
    let config = RouterConfig {
        routing_strategy: RoutingStrategy::PriorityBased,
        num_retries,
        retry_after_secs: 0,
        ..Default::default()
    };
    let router = Router::new(config);
    let mut primary = create_test_deployment("same-provider-expensive", "shared").await;
    primary.model = "gpt-expensive".to_string();
    primary.config.priority = 0;
    let mut fallback = create_test_deployment("same-provider-cheap", "shared").await;
    fallback.model = "gpt-cheap".to_string();
    fallback.config.priority = 10;
    router.add_deployment(primary);
    router.add_deployment(fallback);
    router
}

#[tokio::test]
async fn test_execute_with_retry_budget_fallback_ignores_retry_limit_and_provider_scope() {
    let router = build_same_provider_budget_fallback_router(0).await;
    let attempts = std::sync::Arc::new(std::sync::Mutex::new(Vec::new()));

    let result = router
        .execute_with_selected_deployment_retry("shared", {
            let attempts = attempts.clone();
            move |deployment| {
                let attempts = attempts.clone();
                async move {
                    attempts.lock().unwrap().push(deployment.model.clone());
                    if deployment.model == "gpt-expensive" {
                        Err(ProviderError::quota_exceeded(
                            "budget",
                            "provider 'openai' budget exceeded",
                        ))
                    } else {
                        Ok((deployment.id.clone(), 0))
                    }
                }
            }
        })
        .await
        .expect("budget fallback should select another same-provider deployment");

    assert_eq!(result.0, "same-provider-cheap");
    assert_eq!(
        attempts.lock().unwrap().as_slice(),
        ["gpt-expensive", "gpt-cheap"]
    );
    assert_eq!(result.2, 1);
    let primary = router
        .get_deployment("same-provider-expensive")
        .expect("primary deployment should exist");
    assert_eq!(primary.state.fail_requests.load(Ordering::Relaxed), 0);
}

#[tokio::test]
async fn test_execute_with_capability_retry_budget_fallback_ignores_retry_limit() {
    let router = build_same_provider_budget_fallback_router(0).await;
    let attempts = std::sync::Arc::new(std::sync::Mutex::new(Vec::new()));

    let result = router
        .execute_with_selected_deployment_capability_retry(
            "shared",
            &ProviderCapability::ChatCompletion,
            {
                let attempts = attempts.clone();
                move |deployment| {
                    let attempts = attempts.clone();
                    async move {
                        attempts.lock().unwrap().push(deployment.model.clone());
                        if deployment.model == "gpt-expensive" {
                            Err(ProviderError::quota_exceeded(
                                "budget",
                                "provider 'openai' budget exceeded",
                            ))
                        } else {
                            Ok((deployment.id.clone(), 0))
                        }
                    }
                }
            },
        )
        .await
        .expect("capability retry should select another same-provider deployment");

    assert_eq!(result.0, "same-provider-cheap");
    assert_eq!(
        attempts.lock().unwrap().as_slice(),
        ["gpt-expensive", "gpt-cheap"]
    );
    assert_eq!(result.2, 1);
    let primary = router
        .get_deployment("same-provider-expensive")
        .expect("primary deployment should exist");
    assert_eq!(primary.state.fail_requests.load(Ordering::Relaxed), 0);
}

#[tokio::test]
async fn test_execute_with_retry_exhausted() {
    let config = RouterConfig {
        num_retries: 2,
        retry_after_secs: 0,
        cooldown_time_secs: 0,
        ..Default::default()
    };
    let router = Router::new(config);
    let deployment = create_test_deployment("test-1", "gpt-4").await;
    router.add_deployment(deployment);

    let result = router
        .execute_with_retry("gpt-4", |_deployment_id| async move {
            Err::<(String, u64), _>(ProviderError::timeout("test", "Request timed out"))
        })
        .await;

    assert!(result.is_err());
    let (error, attempts) = result.unwrap_err();
    assert_eq!(attempts, 3);
    assert!(matches!(error, ProviderError::Timeout { .. }));
}

#[tokio::test]
async fn test_execute_with_retry_non_retryable_error() {
    let config = RouterConfig {
        num_retries: 3,
        ..Default::default()
    };
    let router = Router::new(config);
    let deployment = create_test_deployment("test-1", "gpt-4").await;
    router.add_deployment(deployment);

    let result = router
        .execute_with_retry("gpt-4", |_deployment_id| async move {
            Err::<(String, u64), _>(ProviderError::authentication("test", "Invalid API key"))
        })
        .await;

    assert!(result.is_err());
    let (_error, attempts) = result.unwrap_err();
    assert_eq!(attempts, 1);
}

#[tokio::test]
async fn test_execute_with_fallback() {
    let config = RouterConfig {
        num_retries: 1,
        retry_after_secs: 0,
        max_fallbacks: 2,
        ..Default::default()
    };

    let fallback_config =
        FallbackConfig::new().add_general("gpt-4", vec!["gpt-3.5-turbo".to_string()]);

    let router = Router::new(config).with_fallback_config(fallback_config);

    let deployment1 = create_test_deployment("test-gpt4", "gpt-4").await;
    let deployment2 = create_test_deployment("test-gpt3.5", "gpt-3.5-turbo").await;
    router.add_deployment(deployment1);
    router.add_deployment(deployment2);

    let call_count = std::sync::Arc::new(std::sync::atomic::AtomicU32::new(0));
    let call_count_clone = call_count.clone();

    let result: Result<ExecutionResult<String>, _> = router
        .execute("gpt-4", move |deployment_id| {
            let call_count = call_count_clone.clone();
            async move {
                let count = call_count.fetch_add(1, Ordering::Relaxed);
                if deployment_id.contains("gpt4") {
                    Err(ProviderError::timeout("test", "gpt-4 timed out"))
                } else {
                    Ok((format!("fallback-{}", count), 100u64))
                }
            }
        })
        .await;

    assert!(result.is_ok());
    let exec_result = result.unwrap();
    assert!(exec_result.used_fallback);
    assert!(exec_result.model_used.contains("gpt-3.5-turbo"));
    assert!(exec_result.attempts > 1);
}

#[tokio::test]
async fn test_execute_all_models_fail() {
    let config = RouterConfig {
        num_retries: 1,
        retry_after_secs: 0,
        max_fallbacks: 2,
        ..Default::default()
    };

    let fallback_config =
        FallbackConfig::new().add_general("gpt-4", vec!["gpt-3.5-turbo".to_string()]);

    let router = Router::new(config).with_fallback_config(fallback_config);

    let deployment1 = create_test_deployment("test-gpt4", "gpt-4").await;
    let deployment2 = create_test_deployment("test-gpt3.5", "gpt-3.5-turbo").await;
    router.add_deployment(deployment1);
    router.add_deployment(deployment2);

    let result: Result<ExecutionResult<String>, _> = router
        .execute("gpt-4", |_deployment_id| async move {
            Err::<(String, u64), _>(ProviderError::timeout("test", "All models timed out"))
        })
        .await;

    assert!(result.is_err());
    assert!(matches!(
        result.unwrap_err(),
        RouterError::NoAvailableDeployment(_)
    ));
}

#[tokio::test]
async fn test_execute_respects_max_fallbacks() {
    let config = RouterConfig {
        num_retries: 0,
        max_fallbacks: 1,
        retry_after_secs: 0,
        ..Default::default()
    };

    let fallback_config = FallbackConfig::new().add_general(
        "gpt-4",
        vec![
            "fallback-1".to_string(),
            "fallback-2".to_string(),
            "fallback-3".to_string(),
        ],
    );

    let router = Router::new(config).with_fallback_config(fallback_config);

    let deployment1 = create_test_deployment("test-gpt4", "gpt-4").await;
    let deployment2 = create_test_deployment("test-fb1", "fallback-1").await;
    let deployment3 = create_test_deployment("test-fb2", "fallback-2").await;
    let deployment4 = create_test_deployment("test-fb3", "fallback-3").await;
    router.add_deployment(deployment1);
    router.add_deployment(deployment2);
    router.add_deployment(deployment3);
    router.add_deployment(deployment4);

    let tried_models = std::sync::Arc::new(std::sync::Mutex::new(Vec::new()));
    let tried_models_clone = tried_models.clone();

    let result: Result<ExecutionResult<String>, _> = router
        .execute("gpt-4", move |deployment_id| {
            let tried = tried_models_clone.clone();
            async move {
                tried.lock().unwrap().push(deployment_id.clone());
                Err::<(String, u64), _>(ProviderError::timeout("test", "Failed"))
            }
        })
        .await;

    assert!(result.is_err());

    let models = tried_models.lock().unwrap();
    assert!(
        models.len() <= 2,
        "Tried {} models, expected <= 2",
        models.len()
    );
}

#[tokio::test]
async fn test_execute_records_metrics() {
    let router = Router::default();
    let deployment = create_test_deployment("test-1", "gpt-4").await;
    router.add_deployment(deployment);

    let result = router
        .execute_once("gpt-4", |_deployment_id| async move {
            Ok(("success".to_string(), 500u64))
        })
        .await;

    assert!(result.is_ok());

    if let Some(d) = router.get_deployment("test-1") {
        assert_eq!(d.state.total_requests.load(Ordering::Relaxed), 1);
        assert!(d.state.avg_latency_us.load(Ordering::Relaxed) > 0);
    }
}

// ==================== Additional Edge Case Tests ====================

#[tokio::test]
async fn test_execute_with_rate_limit_error() {
    let config = RouterConfig {
        num_retries: 2,
        retry_after_secs: 0,
        cooldown_time_secs: 0,
        ..Default::default()
    };
    let router = Router::new(config);
    let deployment = create_test_deployment("test-1", "gpt-4").await;
    router.add_deployment(deployment);

    let attempt_count = std::sync::Arc::new(std::sync::atomic::AtomicU32::new(0));
    let attempt_count_clone = attempt_count.clone();

    let result = router
        .execute_with_retry("gpt-4", move |_deployment_id| {
            let attempt_count = attempt_count_clone.clone();
            async move {
                let current = attempt_count.fetch_add(1, Ordering::Relaxed);
                if current < 2 {
                    Err(ProviderError::rate_limit("test", Some(1)))
                } else {
                    Ok(("success after rate limit".to_string(), 100u64))
                }
            }
        })
        .await;

    assert!(result.is_ok());
    let (_value, _deployment_id, attempts, _latency) = result.unwrap();
    assert_eq!(attempts, 3);
}

#[tokio::test]
async fn test_execute_deployment_selection_failure() {
    let router = Router::default();

    // No deployments added
    let result = router
        .execute_with_retry("nonexistent-model", |_deployment_id| async move {
            Ok(("should not reach here".to_string(), 100u64))
        })
        .await;

    assert!(result.is_err());
    let (_error, attempts) = result.unwrap_err();
    assert_eq!(attempts, 1); // Should fail immediately on deployment selection
}

#[tokio::test]
async fn test_execute_max_retries_exceeded() {
    let config = RouterConfig {
        num_retries: 3,
        retry_after_secs: 0,
        cooldown_time_secs: 0,
        ..Default::default()
    };
    let router = Router::new(config);
    let deployment = create_test_deployment("test-1", "gpt-4").await;
    router.add_deployment(deployment);

    let attempt_count = std::sync::Arc::new(std::sync::atomic::AtomicU32::new(0));
    let attempt_count_clone = attempt_count.clone();

    let result = router
        .execute_with_retry("gpt-4", move |_deployment_id| {
            let attempt_count = attempt_count_clone.clone();
            async move {
                attempt_count.fetch_add(1, Ordering::Relaxed);
                Err::<(String, u64), _>(ProviderError::timeout("test", "Always timeout"))
            }
        })
        .await;

    assert!(result.is_err());
    let (_error, attempts) = result.unwrap_err();
    assert_eq!(attempts, 4); // Initial attempt + 3 retries
}