Make gateway Open Responses compliant

This commit is contained in:
2026-03-02 04:21:29 +00:00
parent 47d517c913
commit 3e645a3525
6 changed files with 858 additions and 453 deletions

View File

@@ -5,6 +5,10 @@ import (
"fmt"
"log"
"net/http"
"strings"
"time"
"github.com/google/uuid"
"github.com/yourusername/go-llm-gateway/internal/api"
"github.com/yourusername/go-llm-gateway/internal/conversation"
@@ -74,16 +78,34 @@ func (s *GatewayServer) handleResponses(w http.ResponseWriter, r *http.Request)
return
}
// Build full message history
messages := s.buildMessageHistory(&req)
if messages == nil {
http.Error(w, "conversation not found", http.StatusNotFound)
return
// Normalize input to internal messages
inputMsgs := req.NormalizeInput()
// Build full message history from previous conversation
var historyMsgs []api.Message
if req.PreviousResponseID != nil && *req.PreviousResponseID != "" {
conv, ok := s.convs.Get(*req.PreviousResponseID)
if !ok {
http.Error(w, "conversation not found", http.StatusNotFound)
return
}
historyMsgs = conv.Messages
}
// Update request with full history for provider
fullReq := req
fullReq.Input = messages
// Combined messages for conversation storage (history + new input, no instructions)
storeMsgs := make([]api.Message, 0, len(historyMsgs)+len(inputMsgs))
storeMsgs = append(storeMsgs, historyMsgs...)
storeMsgs = append(storeMsgs, inputMsgs...)
// Build provider messages: instructions + history + input
var providerMsgs []api.Message
if req.Instructions != nil && *req.Instructions != "" {
providerMsgs = append(providerMsgs, api.Message{
Role: "developer",
Content: []api.ContentBlock{{Type: "input_text", Text: *req.Instructions}},
})
}
providerMsgs = append(providerMsgs, storeMsgs...)
provider, err := s.resolveProvider(&req)
if err != nil {
@@ -91,64 +113,44 @@ func (s *GatewayServer) handleResponses(w http.ResponseWriter, r *http.Request)
return
}
// Resolve provider_model_id (e.g., Azure deployment name) before sending to provider
fullReq.Model = s.registry.ResolveModelID(req.Model)
// Resolve provider_model_id (e.g., Azure deployment name)
resolvedReq := req
resolvedReq.Model = s.registry.ResolveModelID(req.Model)
// Handle streaming vs non-streaming
if req.Stream {
s.handleStreamingResponse(w, r, provider, &fullReq, &req)
s.handleStreamingResponse(w, r, provider, providerMsgs, &resolvedReq, &req, storeMsgs)
} else {
s.handleSyncResponse(w, r, provider, &fullReq, &req)
s.handleSyncResponse(w, r, provider, providerMsgs, &resolvedReq, &req, storeMsgs)
}
}
func (s *GatewayServer) buildMessageHistory(req *api.ResponseRequest) []api.Message {
// If no previous_response_id, use input as-is
if req.PreviousResponseID == "" {
return req.Input
}
// Load previous conversation
conv, ok := s.convs.Get(req.PreviousResponseID)
if !ok {
return nil
}
// Append new input to conversation history
messages := make([]api.Message, len(conv.Messages))
copy(messages, conv.Messages)
messages = append(messages, req.Input...)
return messages
}
func (s *GatewayServer) handleSyncResponse(w http.ResponseWriter, r *http.Request, provider providers.Provider, fullReq *api.ResponseRequest, origReq *api.ResponseRequest) {
resp, err := provider.Generate(r.Context(), fullReq)
func (s *GatewayServer) handleSyncResponse(w http.ResponseWriter, r *http.Request, provider providers.Provider, providerMsgs []api.Message, resolvedReq *api.ResponseRequest, origReq *api.ResponseRequest, storeMsgs []api.Message) {
result, err := provider.Generate(r.Context(), providerMsgs, resolvedReq)
if err != nil {
s.logger.Printf("provider %s error: %v", provider.Name(), err)
http.Error(w, "provider error", http.StatusBadGateway)
return
}
// Store conversation - use previous_response_id if continuing, otherwise use new ID
conversationID := origReq.PreviousResponseID
if conversationID == "" {
conversationID = resp.ID
responseID := generateID("resp_")
// Build assistant message for conversation store
assistantMsg := api.Message{
Role: "assistant",
Content: []api.ContentBlock{{Type: "output_text", Text: result.Text}},
}
messages := append(fullReq.Input, resp.Output...)
s.convs.Create(conversationID, resp.Model, messages)
// Return the conversation ID (not the provider's response ID)
resp.ID = conversationID
allMsgs := append(storeMsgs, assistantMsg)
s.convs.Create(responseID, result.Model, allMsgs)
// Build spec-compliant response
resp := s.buildResponse(origReq, result, provider.Name(), responseID)
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(http.StatusOK)
_ = json.NewEncoder(w).Encode(resp)
}
func (s *GatewayServer) handleStreamingResponse(w http.ResponseWriter, r *http.Request, provider providers.Provider, fullReq *api.ResponseRequest, origReq *api.ResponseRequest) {
// Set headers for SSE
func (s *GatewayServer) handleStreamingResponse(w http.ResponseWriter, r *http.Request, provider providers.Provider, providerMsgs []api.Message, resolvedReq *api.ResponseRequest, origReq *api.ResponseRequest, storeMsgs []api.Message) {
w.Header().Set("Content-Type", "text/event-stream")
w.Header().Set("Cache-Control", "no-cache")
w.Header().Set("Connection", "keep-alive")
@@ -160,89 +162,322 @@ func (s *GatewayServer) handleStreamingResponse(w http.ResponseWriter, r *http.R
return
}
chunkChan, errChan := provider.GenerateStream(r.Context(), fullReq)
var responseID string
var fullText string
responseID := generateID("resp_")
itemID := generateID("msg_")
seq := 0
outputIdx := 0
contentIdx := 0
// Build initial response snapshot (in_progress, no output yet)
initialResp := s.buildResponse(origReq, &api.ProviderResult{
Model: origReq.Model,
}, provider.Name(), responseID)
initialResp.Status = "in_progress"
initialResp.CompletedAt = nil
initialResp.Output = []api.OutputItem{}
initialResp.Usage = nil
// response.created
s.sendSSE(w, flusher, &seq, "response.created", &api.StreamEvent{
Type: "response.created",
Response: initialResp,
})
// response.in_progress
s.sendSSE(w, flusher, &seq, "response.in_progress", &api.StreamEvent{
Type: "response.in_progress",
Response: initialResp,
})
// response.output_item.added
inProgressItem := &api.OutputItem{
ID: itemID,
Type: "message",
Status: "in_progress",
Role: "assistant",
Content: []api.ContentPart{},
}
s.sendSSE(w, flusher, &seq, "response.output_item.added", &api.StreamEvent{
Type: "response.output_item.added",
OutputIndex: &outputIdx,
Item: inProgressItem,
})
// response.content_part.added
emptyPart := &api.ContentPart{
Type: "output_text",
Text: "",
Annotations: []api.Annotation{},
}
s.sendSSE(w, flusher, &seq, "response.content_part.added", &api.StreamEvent{
Type: "response.content_part.added",
ItemID: itemID,
OutputIndex: &outputIdx,
ContentIndex: &contentIdx,
Part: emptyPart,
})
// Start provider stream
deltaChan, errChan := provider.GenerateStream(r.Context(), providerMsgs, resolvedReq)
var fullText string
var streamErr error
var providerModel string
loop:
for {
select {
case chunk, ok := <-chunkChan:
case delta, ok := <-deltaChan:
if !ok {
return
break loop
}
// Capture response ID
if chunk.ID != "" && responseID == "" {
responseID = chunk.ID
if delta.Model != "" && providerModel == "" {
providerModel = delta.Model
}
// Override chunk ID with conversation ID
if origReq.PreviousResponseID != "" {
chunk.ID = origReq.PreviousResponseID
} else if responseID != "" {
chunk.ID = responseID
if delta.Text != "" {
fullText += delta.Text
s.sendSSE(w, flusher, &seq, "response.output_text.delta", &api.StreamEvent{
Type: "response.output_text.delta",
ItemID: itemID,
OutputIndex: &outputIdx,
ContentIndex: &contentIdx,
Delta: delta.Text,
})
}
// Accumulate text from deltas
if chunk.Delta != nil && len(chunk.Delta.Content) > 0 {
for _, block := range chunk.Delta.Content {
fullText += block.Text
}
if delta.Done {
break loop
}
data, err := json.Marshal(chunk)
if err != nil {
s.logger.Printf("failed to marshal chunk: %v", err)
continue
}
fmt.Fprintf(w, "data: %s\n\n", data)
flusher.Flush()
if chunk.Done {
// Store conversation with a single consolidated assistant message
s.storeStreamConversation(fullReq, origReq, responseID, fullText)
return
}
case err := <-errChan:
if err != nil {
s.logger.Printf("stream error: %v", err)
errData, _ := json.Marshal(map[string]string{"error": err.Error()})
fmt.Fprintf(w, "data: %s\n\n", errData)
flusher.Flush()
streamErr = err
}
// Store whatever we accumulated before the error
s.storeStreamConversation(fullReq, origReq, responseID, fullText)
return
break loop
case <-r.Context().Done():
s.logger.Printf("client disconnected")
return
}
}
}
func (s *GatewayServer) storeStreamConversation(fullReq *api.ResponseRequest, origReq *api.ResponseRequest, responseID string, fullText string) {
if responseID == "" || fullText == "" {
if streamErr != nil {
s.logger.Printf("stream error: %v", streamErr)
failedResp := s.buildResponse(origReq, &api.ProviderResult{
Model: origReq.Model,
}, provider.Name(), responseID)
failedResp.Status = "failed"
failedResp.CompletedAt = nil
failedResp.Output = []api.OutputItem{}
failedResp.Error = &api.ResponseError{
Type: "server_error",
Message: streamErr.Error(),
}
s.sendSSE(w, flusher, &seq, "response.failed", &api.StreamEvent{
Type: "response.failed",
Response: failedResp,
})
return
}
assistantMsg := api.Message{
Role: "assistant",
Content: []api.ContentBlock{
{Type: "output_text", Text: fullText},
},
}
messages := append(fullReq.Input, assistantMsg)
// response.output_text.done
s.sendSSE(w, flusher, &seq, "response.output_text.done", &api.StreamEvent{
Type: "response.output_text.done",
ItemID: itemID,
OutputIndex: &outputIdx,
ContentIndex: &contentIdx,
Text: fullText,
})
conversationID := origReq.PreviousResponseID
if conversationID == "" {
conversationID = responseID
// response.content_part.done
completedPart := &api.ContentPart{
Type: "output_text",
Text: fullText,
Annotations: []api.Annotation{},
}
s.sendSSE(w, flusher, &seq, "response.content_part.done", &api.StreamEvent{
Type: "response.content_part.done",
ItemID: itemID,
OutputIndex: &outputIdx,
ContentIndex: &contentIdx,
Part: completedPart,
})
// response.output_item.done
completedItem := &api.OutputItem{
ID: itemID,
Type: "message",
Status: "completed",
Role: "assistant",
Content: []api.ContentPart{*completedPart},
}
s.sendSSE(w, flusher, &seq, "response.output_item.done", &api.StreamEvent{
Type: "response.output_item.done",
OutputIndex: &outputIdx,
Item: completedItem,
})
// Build final completed response
model := origReq.Model
if providerModel != "" {
model = providerModel
}
finalResult := &api.ProviderResult{
Model: model,
Text: fullText,
}
completedResp := s.buildResponse(origReq, finalResult, provider.Name(), responseID)
completedResp.Output[0].ID = itemID
// response.completed
s.sendSSE(w, flusher, &seq, "response.completed", &api.StreamEvent{
Type: "response.completed",
Response: completedResp,
})
// Store conversation
if fullText != "" {
assistantMsg := api.Message{
Role: "assistant",
Content: []api.ContentBlock{{Type: "output_text", Text: fullText}},
}
allMsgs := append(storeMsgs, assistantMsg)
s.convs.Create(responseID, model, allMsgs)
}
}
func (s *GatewayServer) sendSSE(w http.ResponseWriter, flusher http.Flusher, seq *int, eventType string, event *api.StreamEvent) {
event.SequenceNumber = *seq
*seq++
data, err := json.Marshal(event)
if err != nil {
s.logger.Printf("failed to marshal SSE event: %v", err)
return
}
fmt.Fprintf(w, "event: %s\ndata: %s\n\n", eventType, data)
flusher.Flush()
}
func (s *GatewayServer) buildResponse(req *api.ResponseRequest, result *api.ProviderResult, providerName string, responseID string) *api.Response {
now := time.Now().Unix()
model := result.Model
if model == "" {
model = req.Model
}
s.convs.Create(conversationID, fullReq.Model, messages)
// Build output item
itemID := generateID("msg_")
outputItem := api.OutputItem{
ID: itemID,
Type: "message",
Status: "completed",
Role: "assistant",
Content: []api.ContentPart{{
Type: "output_text",
Text: result.Text,
Annotations: []api.Annotation{},
}},
}
// Echo back request params with defaults
tools := req.Tools
if tools == nil {
tools = json.RawMessage(`[]`)
}
toolChoice := req.ToolChoice
if toolChoice == nil {
toolChoice = json.RawMessage(`"auto"`)
}
text := req.Text
if text == nil {
text = json.RawMessage(`{"format":{"type":"text"}}`)
}
truncation := "disabled"
if req.Truncation != nil {
truncation = *req.Truncation
}
temperature := 1.0
if req.Temperature != nil {
temperature = *req.Temperature
}
topP := 1.0
if req.TopP != nil {
topP = *req.TopP
}
presencePenalty := 0.0
if req.PresencePenalty != nil {
presencePenalty = *req.PresencePenalty
}
frequencyPenalty := 0.0
if req.FrequencyPenalty != nil {
frequencyPenalty = *req.FrequencyPenalty
}
topLogprobs := 0
if req.TopLogprobs != nil {
topLogprobs = *req.TopLogprobs
}
parallelToolCalls := true
if req.ParallelToolCalls != nil {
parallelToolCalls = *req.ParallelToolCalls
}
store := true
if req.Store != nil {
store = *req.Store
}
background := false
if req.Background != nil {
background = *req.Background
}
serviceTier := "default"
if req.ServiceTier != nil {
serviceTier = *req.ServiceTier
}
var reasoning json.RawMessage
if req.Reasoning != nil {
reasoning = req.Reasoning
}
metadata := req.Metadata
if metadata == nil {
metadata = map[string]string{}
}
var usage *api.Usage
if result.Text != "" {
usage = &result.Usage
}
return &api.Response{
ID: responseID,
Object: "response",
CreatedAt: now,
CompletedAt: &now,
Status: "completed",
IncompleteDetails: nil,
Model: model,
PreviousResponseID: req.PreviousResponseID,
Instructions: req.Instructions,
Output: []api.OutputItem{outputItem},
Error: nil,
Tools: tools,
ToolChoice: toolChoice,
Truncation: truncation,
ParallelToolCalls: parallelToolCalls,
Text: text,
TopP: topP,
PresencePenalty: presencePenalty,
FrequencyPenalty: frequencyPenalty,
TopLogprobs: topLogprobs,
Temperature: temperature,
Reasoning: reasoning,
Usage: usage,
MaxOutputTokens: req.MaxOutputTokens,
MaxToolCalls: req.MaxToolCalls,
Store: store,
Background: background,
ServiceTier: serviceTier,
Metadata: metadata,
SafetyIdentifier: nil,
PromptCacheKey: nil,
Provider: providerName,
}
}
func (s *GatewayServer) resolveProvider(req *api.ResponseRequest) (providers.Provider, error) {
@@ -254,3 +489,8 @@ func (s *GatewayServer) resolveProvider(req *api.ResponseRequest) (providers.Pro
}
return s.registry.Default(req.Model)
}
func generateID(prefix string) string {
id := strings.ReplaceAll(uuid.NewString(), "-", "")
return prefix + id[:24]
}