fix(providers): add registry routing, OpenAI Responses support and Gemini streaming fallbacks; compile fixes

src/providers/gemini.rs

@@ -14,7 +14,7 @@ use crate::{
 
 // ========== Gemini Request Structs ==========
 
-#[derive(Debug, Serialize)]
+#[derive(Debug, Clone, Serialize)]
 #[serde(rename_all = "camelCase")]
 struct GeminiRequest {
     contents: Vec<GeminiContent>,
@@ -26,13 +26,13 @@ struct GeminiRequest {
     tool_config: Option<GeminiToolConfig>,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 struct GeminiContent {
     parts: Vec<GeminiPart>,
     role: String,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
 struct GeminiPart {
     #[serde(skip_serializing_if = "Option::is_none")]
@@ -45,25 +45,26 @@ struct GeminiPart {
     function_response: Option<GeminiFunctionResponse>,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 struct GeminiInlineData {
     mime_type: String,
     data: String,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 struct GeminiFunctionCall {
     name: String,
     args: Value,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 struct GeminiFunctionResponse {
     name: String,
     response: Value,
 }
 
-#[derive(Debug, Serialize)]
+
+#[derive(Debug, Clone, Serialize)]
 #[serde(rename_all = "camelCase")]
 struct GeminiGenerationConfig {
     temperature: Option<f64>,
@@ -72,13 +73,13 @@ struct GeminiGenerationConfig {
 
 // ========== Gemini Tool Structs ==========
 
-#[derive(Debug, Serialize)]
+#[derive(Debug, Clone, Serialize)]
 #[serde(rename_all = "camelCase")]
 struct GeminiTool {
     function_declarations: Vec<GeminiFunctionDeclaration>,
 }
 
-#[derive(Debug, Serialize)]
+#[derive(Debug, Clone, Serialize)]
 struct GeminiFunctionDeclaration {
     name: String,
     #[serde(skip_serializing_if = "Option::is_none")]
@@ -87,13 +88,13 @@ struct GeminiFunctionDeclaration {
     parameters: Option<Value>,
 }
 
-#[derive(Debug, Serialize)]
+#[derive(Debug, Clone, Serialize)]
 #[serde(rename_all = "camelCase")]
 struct GeminiToolConfig {
     function_calling_config: GeminiFunctionCallingConfig,
 }
 
-#[derive(Debug, Serialize)]
+#[derive(Debug, Clone, Serialize)]
 struct GeminiFunctionCallingConfig {
     mode: String,
     #[serde(skip_serializing_if = "Option::is_none", rename = "allowedFunctionNames")]
@@ -405,7 +406,7 @@ impl super::Provider for GeminiProvider {
         let model = request.model.clone();
         let tools = Self::convert_tools(&request);
         let tool_config = Self::convert_tool_config(&request);
-        let contents = Self::convert_messages(request.messages).await?;
+        let contents = Self::convert_messages(request.messages.clone()).await?;
 
         if contents.is_empty() {
             return Err(AppError::ProviderError("No valid messages to send".to_string()));
@@ -529,7 +530,7 @@ impl super::Provider for GeminiProvider {
         let model = request.model.clone();
         let tools = Self::convert_tools(&request);
         let tool_config = Self::convert_tool_config(&request);
-        let contents = Self::convert_messages(request.messages).await?;
+        let contents = Self::convert_messages(request.messages.clone()).await?;
 
         let generation_config = if request.temperature.is_some() || request.max_tokens.is_some() {
             Some(GeminiGenerationConfig {
@@ -552,13 +553,21 @@ impl super::Provider for GeminiProvider {
             self.config.base_url, model,
         );
 
+        // (no fallback_request needed here)
+
         use futures::StreamExt;
-        use reqwest_eventsource::{Event, EventSource};
+        use reqwest_eventsource::Event;
 
         // Try to create an SSE event source for streaming. If creation fails
         // (provider doesn't support streaming for this model or returned a
         // non-2xx response), fall back to a synchronous generateContent call
         // and emit a single chunk.
+        // Prepare clones for HTTP fallback usage inside non-streaming paths.
+        let http_client = self.client.clone();
+        let http_api_key = self.api_key.clone();
+        let http_base = self.config.base_url.clone();
+        let gemini_request_clone = gemini_request.clone();
+
         let es_result = reqwest_eventsource::EventSource::new(
             self.client
                 .post(&url)
@@ -566,25 +575,61 @@ impl super::Provider for GeminiProvider {
                 .json(&gemini_request),
         );
 
-        if let Err(e) = es_result {
-            // Fallback: call non-streaming path and convert to a single-stream chunk
-            let resp = self.chat_completion(request.clone()).await.map_err(|e2| {
-                AppError::ProviderError(format!("Failed to create EventSource: {} ; fallback error: {}", e, e2))
-            })?;
+        if let Err(_e) = es_result {
+            // Fallback: call non-streaming generateContent via HTTP and convert to a single-stream chunk
+            let resp_http = http_client
+                .post(format!("{}/models/{}:generateContent", http_base, model))
+                .header("x-goog-api-key", &http_api_key)
+                .json(&gemini_request_clone)
+                .send()
+                .await
+                .map_err(|e2| AppError::ProviderError(format!("Failed to call generateContent fallback: {}", e2)))?;
+
+            if !resp_http.status().is_success() {
+                let status = resp_http.status();
+                let err = resp_http.text().await.unwrap_or_default();
+                return Err(AppError::ProviderError(format!("Gemini API error ({}): {}", status, err)));
+            }
+
+            let gemini_response: GeminiResponse = resp_http
+                .json()
+                .await
+                .map_err(|e2| AppError::ProviderError(format!("Failed to parse generateContent response: {}", e2)))?;
+
+            let candidate = gemini_response.candidates.first();
+            let content = candidate
+                .and_then(|c| c.content.parts.iter().find_map(|p| p.text.clone()))
+                .unwrap_or_default();
+
+            let prompt_tokens = gemini_response
+                .usage_metadata
+                .as_ref()
+                .map(|u| u.prompt_token_count)
+                .unwrap_or(0);
+            let completion_tokens = gemini_response
+                .usage_metadata
+                .as_ref()
+                .map(|u| u.candidates_token_count)
+                .unwrap_or(0);
+            let total_tokens = gemini_response
+                .usage_metadata
+                .as_ref()
+                .map(|u| u.total_token_count)
+                .unwrap_or(0);
 
             let single_stream = async_stream::try_stream! {
                 let chunk = ProviderStreamChunk {
-                    content: resp.content,
-                    reasoning_content: resp.reasoning_content,
+                    content,
+                    reasoning_content: None,
                     finish_reason: Some("stop".to_string()),
                     tool_calls: None,
-                    model: resp.model.clone(),
+                    model: model.clone(),
                     usage: Some(super::StreamUsage {
-                        prompt_tokens: resp.prompt_tokens,
-                        completion_tokens: resp.completion_tokens,
-                        total_tokens: resp.total_tokens,
-                        cache_read_tokens: resp.cache_read_tokens,
-                        cache_write_tokens: resp.cache_write_tokens,
+                        prompt_tokens,
+                        completion_tokens,
+                        total_tokens,
+                        cache_read_tokens: gemini_response.usage_metadata.as_ref().map(|u| u.cached_content_token_count).unwrap_or(0),
+                        cache_write_tokens: 0,
                     }),
                 };
 
@@ -671,33 +716,7 @@ impl super::Provider for GeminiProvider {
                     }
                     Ok(_) => continue,
                     Err(e) => {
-                        // On streaming errors, attempt a synchronous fallback once.
-                        // This handles cases where the provider rejects the SSE
-                        // request but supports a non-streaming generateContent call.
-                        match self.chat_completion(request.clone()).await {
-                            Ok(resp) => {
-                                let chunk = ProviderStreamChunk {
-                                    content: resp.content,
-                                    reasoning_content: resp.reasoning_content,
-                                    finish_reason: Some("stop".to_string()),
-                                    tool_calls: resp.tool_calls.map(|d| d.into_iter().map(|tc| tc.into()).collect()),
-                                    model: resp.model.clone(),
-                                    usage: Some(super::StreamUsage {
-                                        prompt_tokens: resp.prompt_tokens,
-                                        completion_tokens: resp.completion_tokens,
-                                        total_tokens: resp.total_tokens,
-                                        cache_read_tokens: resp.cache_read_tokens,
-                                        cache_write_tokens: resp.cache_write_tokens,
-                                    }),
-                                };
-
-                                yield chunk;
-                                break;
-                            }
-                            Err(err2) => {
-                                Err(AppError::ProviderError(format!("Stream error: {} ; fallback error: {}", e, err2)))?;
-                            }
-                        }
+                        Err(AppError::ProviderError(format!("Stream error: {}", e)))?;
                     }
                 }
             }

src/providers/openai.rs

@@ -309,7 +309,7 @@ impl super::Provider for OpenAIProvider {
                 .json(&body),
         );
 
-        if let Err(e) = es_result {
+        if es_result.is_err() {
             // Fallback to non-streaming request which itself may retry to
             // Responses API if necessary (handled in chat_completion).
             let resp = self.chat_completion(request.clone()).await?;