systemprompt_api/routes/gateway/
models.rs

1use axum::Json;
2use axum::http::{HeaderMap, StatusCode};
3use serde::Serialize;
4use std::collections::BTreeMap;
5use systemprompt_config::ProfileBootstrap;
6use systemprompt_identifiers::headers::INFERENCE_PROTOCOL;
7use systemprompt_models::profile::{ProviderRegistry, WireProtocol};
8
9#[derive(Debug, Serialize)]
10pub struct RootResponse {
11    pub service: &'static str,
12    pub version: &'static str,
13    pub endpoints: Vec<&'static str>,
14}
15
16pub async fn root() -> Json<RootResponse> {
17    Json(RootResponse {
18        service: "systemprompt-gateway",
19        version: env!("CARGO_PKG_VERSION"),
20        endpoints: vec!["/v1/models", "/v1/messages"],
21    })
22}
23
24#[derive(Debug, Serialize)]
25pub struct ModelEntry {
26    #[serde(rename = "type")]
27    pub kind: &'static str,
28    pub id: String,
29    pub display_name: String,
30    pub created_at: String,
31}
32
33#[derive(Debug, Serialize)]
34pub struct ModelsResponse {
35    pub data: Vec<ModelEntry>,
36    pub has_more: bool,
37    #[serde(skip_serializing_if = "Option::is_none")]
38    pub first_id: Option<String>,
39    #[serde(skip_serializing_if = "Option::is_none")]
40    pub last_id: Option<String>,
41}
42
43pub async fn list(headers: HeaderMap) -> Result<Json<ModelsResponse>, (StatusCode, String)> {
44    let profile = ProfileBootstrap::get().map_err(|e| {
45        (
46            StatusCode::SERVICE_UNAVAILABLE,
47            format!("Profile not ready: {e}"),
48        )
49    })?;
50
51    profile
52        .gateway
53        .as_ref()
54        .and_then(systemprompt_models::profile::GatewayState::resolved)
55        .filter(|g| g.enabled)
56        .ok_or_else(|| (StatusCode::NOT_FOUND, "Gateway not enabled".to_owned()))?;
57
58    let protocols = protocols_from_header(&headers)?;
59    let entries = model_entries(&profile.providers, &protocols);
60    let first_id = entries.first().map(|e| e.id.clone());
61    let last_id = entries.last().map(|e| e.id.clone());
62
63    Ok(Json(ModelsResponse {
64        data: entries,
65        has_more: false,
66        first_id,
67        last_id,
68    }))
69}
70
71/// Resolve the `x-inference-protocol` selection header into wire protocols. An
72/// absent or empty header yields the full catalog (empty slice); a present but
73/// unrecognised tag is a misconfiguration and fails with `400` rather than
74/// silently widening the advertised set.
75fn protocols_from_header(headers: &HeaderMap) -> Result<Vec<WireProtocol>, (StatusCode, String)> {
76    let Some(raw) = headers
77        .get(INFERENCE_PROTOCOL)
78        .and_then(|v| v.to_str().ok())
79    else {
80        return Ok(Vec::new());
81    };
82    let mut protocols = Vec::new();
83    for tag in raw.split(',').map(str::trim).filter(|t| !t.is_empty()) {
84        let protocol = WireProtocol::from_tag(tag).ok_or_else(|| {
85            (
86                StatusCode::BAD_REQUEST,
87                format!("unknown {INFERENCE_PROTOCOL} value: {tag}"),
88            )
89        })?;
90        protocols.push(protocol);
91    }
92    Ok(protocols)
93}
94
95pub fn model_entries(registry: &ProviderRegistry, protocols: &[WireProtocol]) -> Vec<ModelEntry> {
96    let mut by_id: BTreeMap<String, ModelEntry> = BTreeMap::new();
97    for id in registry.advertised_model_ids(protocols) {
98        by_id.insert(
99            id.clone(),
100            ModelEntry {
101                kind: "model",
102                display_name: humanize_model_id(&id),
103                id,
104                created_at: "1970-01-01T00:00:00Z".to_owned(),
105            },
106        );
107    }
108    by_id.into_values().collect()
109}
110
111fn humanize_model_id(id: &str) -> String {
112    id.split('-')
113        .map(|part| {
114            let mut chars = part.chars();
115            chars.next().map_or_else(String::new, |c| {
116                c.to_ascii_uppercase().to_string() + chars.as_str()
117            })
118        })
119        .collect::<Vec<_>>()
120        .join(" ")
121}
systemprompt_api/routes/gateway/models.rs

systemprompt_api/routes/gateway/
models.rs
