lean_ctx/proxy/
anthropic.rs1use axum::{
2 body::Body,
3 extract::State,
4 http::{Request, StatusCode},
5 response::Response,
6};
7use serde_json::Value;
8
9use super::compress::compress_tool_result;
10use super::forward;
11use super::ProxyState;
12
13pub async fn handler(
14 State(state): State<ProxyState>,
15 req: Request<Body>,
16) -> Result<Response, StatusCode> {
17 let upstream = state.anthropic_upstream.clone();
18 forward::forward_request(
19 State(state),
20 req,
21 &upstream,
22 "/v1/messages",
23 compress_request_body,
24 "Anthropic",
25 &[],
26 )
27 .await
28}
29
30fn compress_request_body(body: &[u8]) -> (Vec<u8>, usize, usize) {
31 let original_size = body.len();
32
33 let parsed: Value = match serde_json::from_slice(body) {
34 Ok(v) => v,
35 Err(_) => return (body.to_vec(), original_size, original_size),
36 };
37
38 let mut doc = parsed;
39 let mut modified = false;
40
41 if let Some(messages) = doc.get_mut("messages").and_then(|m| m.as_array_mut()) {
42 super::history_prune::prune_history(messages, 6);
43 modified = true;
44
45 for msg in messages.iter_mut() {
46 let role = msg.get("role").and_then(|r| r.as_str()).unwrap_or("");
47 if role != "user" {
48 continue;
49 }
50
51 if let Some(content) = msg.get_mut("content").and_then(|c| c.as_array_mut()) {
52 for block in content.iter_mut() {
53 if block.get("type").and_then(|t| t.as_str()) != Some("tool_result") {
54 continue;
55 }
56
57 if let Some(inner_content) = block.get_mut("content") {
58 modified |= compress_content_field(inner_content, None);
59 }
60 }
61 }
62 }
63 }
64
65 if !modified {
66 return (body.to_vec(), original_size, original_size);
67 }
68
69 match serde_json::to_vec(&doc) {
70 Ok(compressed) => {
71 let compressed_size = compressed.len();
72 (compressed, original_size, compressed_size)
73 }
74 Err(_) => (body.to_vec(), original_size, original_size),
75 }
76}
77
78fn compress_content_field(content: &mut Value, tool_name: Option<&str>) -> bool {
79 match content {
80 Value::String(s) => {
81 let compressed = compress_tool_result(s, tool_name);
82 if compressed.len() < s.len() {
83 *s = compressed;
84 return true;
85 }
86 false
87 }
88 Value::Array(arr) => {
89 let mut modified = false;
90 for item in arr.iter_mut() {
91 if item.get("type").and_then(|t| t.as_str()) == Some("text") {
92 if let Some(text) = item
93 .get_mut("text")
94 .and_then(|t| t.as_str().map(String::from))
95 {
96 let compressed = compress_tool_result(&text, tool_name);
97 if compressed.len() < text.len() {
98 item["text"] = Value::String(compressed);
99 modified = true;
100 }
101 }
102 }
103 }
104 modified
105 }
106 _ => false,
107 }
108}