aether-llm 0.9.18

Multi-provider LLM abstraction layer for the Aether AI agent framework
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137

use aws_sdk_bedrockruntime::error::SdkError;
use aws_sdk_bedrockruntime::operation::converse_stream::ConverseStreamError;
use aws_sdk_bedrockruntime::operation::invoke_model_with_response_stream::InvokeModelWithResponseStreamError;
use aws_sdk_bedrockruntime::primitives::event_stream::EventReceiver;
use aws_sdk_bedrockruntime::types::error::{ConverseStreamOutputError, ResponseStreamError};
use aws_smithy_types::event_stream::RawMessage;
use futures::{Stream, stream};
use std::fmt::Debug;
use std::time::Duration;
use tracing::error;

use super::provider::ModelTarget;
use crate::providers::response_stream::{OpenedStream, StreamAssembler, response_stream};
use crate::{LlmError, LlmResponse, LlmResponseStream, ProviderError, Result};

pub(super) trait BedrockException {
    fn kind(&self) -> ExceptionKind;
}

pub(super) enum ExceptionKind {
    Throttled,
    Transient,
    Other,
}

pub(super) fn stream<T, U, V>(
    send: impl Future<Output = Result<EventReceiver<T, U>>> + Send + 'static,
    decode: impl FnMut(T, &mut StreamAssembler<V>) -> Result<Vec<LlmResponse>> + Send + 'static,
    idle_timeout: Duration,
) -> LlmResponseStream
where
    T: Send + 'static,
    U: BedrockException + Send + 'static,
    V: Ord + Debug + Send + 'static,
{
    response_stream(async move { Ok(OpenedStream::new(events(send.await?))) }, decode, idle_timeout)
}

pub(super) fn request_error<T: BedrockException + Debug>(target: &ModelTarget, error: &SdkError<T>) -> LlmError {
    error!(model = %target.model, error = ?error, "Bedrock API error");
    let message = format!("Bedrock API error: {error}");
    let status = error.raw_response().map(|response| response.status().as_u16());
    let request_id =
        error.raw_response().and_then(|response| response.headers().get("x-amzn-requestid")).map(str::to_string);
    let provider = match error {
        SdkError::TimeoutError(_) => ProviderError::timeout(message),
        SdkError::DispatchFailure(_) => ProviderError::network(message),
        SdkError::ResponseError(_) => ProviderError::server(message),
        SdkError::ServiceError(service) => match service.err().kind() {
            ExceptionKind::Throttled => ProviderError::rate_limit(message),
            ExceptionKind::Transient => ProviderError::server(message),
            ExceptionKind::Other => ProviderError::api(message),
        },
        _ => ProviderError::api(message),
    };
    provider.with_http_metadata(status, request_id).into()
}

impl BedrockException for ConverseStreamError {
    fn kind(&self) -> ExceptionKind {
        match self {
            Self::ThrottlingException(_) => ExceptionKind::Throttled,
            Self::ServiceUnavailableException(_)
            | Self::InternalServerException(_)
            | Self::ModelStreamErrorException(_)
            | Self::ModelTimeoutException(_)
            | Self::ModelNotReadyException(_) => ExceptionKind::Transient,
            _ => ExceptionKind::Other,
        }
    }
}

impl BedrockException for InvokeModelWithResponseStreamError {
    fn kind(&self) -> ExceptionKind {
        match self {
            Self::ThrottlingException(_) | Self::ServiceQuotaExceededException(_) => ExceptionKind::Throttled,
            Self::ServiceUnavailableException(_)
            | Self::InternalServerException(_)
            | Self::ModelStreamErrorException(_)
            | Self::ModelTimeoutException(_)
            | Self::ModelNotReadyException(_) => ExceptionKind::Transient,
            _ => ExceptionKind::Other,
        }
    }
}

impl BedrockException for ConverseStreamOutputError {
    fn kind(&self) -> ExceptionKind {
        match self {
            Self::ThrottlingException(_) => ExceptionKind::Throttled,
            Self::ServiceUnavailableException(_)
            | Self::InternalServerException(_)
            | Self::ModelStreamErrorException(_) => ExceptionKind::Transient,
            _ => ExceptionKind::Other,
        }
    }
}

impl BedrockException for ResponseStreamError {
    fn kind(&self) -> ExceptionKind {
        match self {
            Self::ThrottlingException(_) => ExceptionKind::Throttled,
            Self::ServiceUnavailableException(_)
            | Self::InternalServerException(_)
            | Self::ModelStreamErrorException(_)
            | Self::ModelTimeoutException(_) => ExceptionKind::Transient,
            _ => ExceptionKind::Other,
        }
    }
}

fn stream_error<T: BedrockException>(error: &SdkError<T, RawMessage>) -> LlmError {
    let message = format!("Bedrock stream error: {error}");
    let provider = match error {
        SdkError::ServiceError(service) => match service.err().kind() {
            ExceptionKind::Throttled => ProviderError::rate_limit(message),
            ExceptionKind::Transient => ProviderError::stream_interrupted(message),
            ExceptionKind::Other => ProviderError::api(message),
        },
        _ => ProviderError::stream_interrupted(message),
    };
    provider.into()
}

fn events<T, U>(receiver: EventReceiver<T, U>) -> impl Stream<Item = Result<T>> + Send
where
    T: Send,
    U: BedrockException + Send,
{
    stream::unfold(receiver, |mut receiver| async move {
        let event = receiver.recv().await.map_err(|e| {
            error!("Bedrock stream recv error: {e}");
            stream_error(&e)
        });
        event.transpose().map(|event| (event, receiver))
    })
}