Add model capability caching and clear functions

src/ai/ollama.rs

@@ -2,7 +2,41 @@ use anyhow::Result;
 use chrono::NaiveDate;
 use reqwest::Client;
 use serde::{Deserialize, Serialize};
-use std::time::Duration;
+use std::collections::HashMap;
+use std::sync::{Arc, Mutex};
+use std::time::{Duration, Instant};
+
+// Cache duration: 15 minutes
+const CACHE_DURATION_SECS: u64 = 15 * 60;
+
+// Cached entry with timestamp
+#[derive(Clone)]
+struct CachedEntry<T> {
+    data: T,
+    cached_at: Instant,
+}
+
+impl<T> CachedEntry<T> {
+    fn new(data: T) -> Self {
+        Self {
+            data,
+            cached_at: Instant::now(),
+        }
+    }
+
+    fn is_expired(&self) -> bool {
+        self.cached_at.elapsed().as_secs() > CACHE_DURATION_SECS
+    }
+}
+
+// Global cache for model lists and capabilities
+lazy_static::lazy_static! {
+    static ref MODEL_LIST_CACHE: Arc<Mutex<HashMap<String, CachedEntry<Vec<String>>>>> =
+        Arc::new(Mutex::new(HashMap::new()));
+
+    static ref MODEL_CAPABILITIES_CACHE: Arc<Mutex<HashMap<String, CachedEntry<Vec<ModelCapabilities>>>>> =
+        Arc::new(Mutex::new(HashMap::new()));
+}
 
 #[derive(Clone)]
 pub struct OllamaClient {
@@ -39,8 +73,21 @@ impl OllamaClient {
         self.num_ctx = num_ctx;
     }
 
-    /// List available models on an Ollama server
+    /// List available models on an Ollama server (cached for 15 minutes)
     pub async fn list_models(url: &str) -> Result<Vec<String>> {
+        // Check cache first
+        {
+            let cache = MODEL_LIST_CACHE.lock().unwrap();
+            if let Some(entry) = cache.get(url) {
+                if !entry.is_expired() {
+                    log::debug!("Returning cached model list for {}", url);
+                    return Ok(entry.data.clone());
+                }
+            }
+        }
+
+        log::debug!("Fetching fresh model list from {}", url);
+
         let client = Client::builder()
             .connect_timeout(Duration::from_secs(5))
             .timeout(Duration::from_secs(10))
@@ -53,7 +100,15 @@ impl OllamaClient {
         }
 
         let tags_response: OllamaTagsResponse = response.json().await?;
-        Ok(tags_response.models.into_iter().map(|m| m.name).collect())
+        let models: Vec<String> = tags_response.models.into_iter().map(|m| m.name).collect();
+
+        // Store in cache
+        {
+            let mut cache = MODEL_LIST_CACHE.lock().unwrap();
+            cache.insert(url.to_string(), CachedEntry::new(models.clone()));
+        }
+
+        Ok(models)
     }
 
     /// Check if a model is available on a server
@@ -62,6 +117,30 @@ impl OllamaClient {
         Ok(models.iter().any(|m| m == model_name))
     }
 
+    /// Clear the model list cache for a specific URL or all URLs
+    pub fn clear_model_cache(url: Option<&str>) {
+        let mut cache = MODEL_LIST_CACHE.lock().unwrap();
+        if let Some(url) = url {
+            cache.remove(url);
+            log::debug!("Cleared model list cache for {}", url);
+        } else {
+            cache.clear();
+            log::debug!("Cleared all model list cache entries");
+        }
+    }
+
+    /// Clear the model capabilities cache for a specific URL or all URLs
+    pub fn clear_capabilities_cache(url: Option<&str>) {
+        let mut cache = MODEL_CAPABILITIES_CACHE.lock().unwrap();
+        if let Some(url) = url {
+            cache.remove(url);
+            log::debug!("Cleared model capabilities cache for {}", url);
+        } else {
+            cache.clear();
+            log::debug!("Cleared all model capabilities cache entries");
+        }
+    }
+
     /// Check if a model has vision capabilities using the /api/show endpoint
     pub async fn check_model_capabilities(
         url: &str,
@@ -104,8 +183,21 @@ impl OllamaClient {
         })
     }
 
-    /// List all models with their capabilities from a server
+    /// List all models with their capabilities from a server (cached for 15 minutes)
     pub async fn list_models_with_capabilities(url: &str) -> Result<Vec<ModelCapabilities>> {
+        // Check cache first
+        {
+            let cache = MODEL_CAPABILITIES_CACHE.lock().unwrap();
+            if let Some(entry) = cache.get(url) {
+                if !entry.is_expired() {
+                    log::debug!("Returning cached model capabilities for {}", url);
+                    return Ok(entry.data.clone());
+                }
+            }
+        }
+
+        log::debug!("Fetching fresh model capabilities from {}", url);
+
         let models = Self::list_models(url).await?;
         let mut capabilities = Vec::new();
 
@@ -123,6 +215,12 @@ impl OllamaClient {
             }
         }
 
+        // Store in cache
+        {
+            let mut cache = MODEL_CAPABILITIES_CACHE.lock().unwrap();
+            cache.insert(url.to_string(), CachedEntry::new(capabilities.clone()));
+        }
+
         Ok(capabilities)
     }