Files
llama-swap/proxy/manager.go
2024-11-17 20:49:14 -08:00

154 lines
3.7 KiB
Go

package proxy
import (
"bytes"
"encoding/json"
"fmt"
"io"
"net/http"
"sync"
"time"
)
type ProxyManager struct {
sync.Mutex
config *Config
currentProcess *Process
logMonitor *LogMonitor
}
func New(config *Config) *ProxyManager {
return &ProxyManager{config: config, currentProcess: nil, logMonitor: NewLogMonitor()}
}
func (pm *ProxyManager) HandleFunc(w http.ResponseWriter, r *http.Request) {
// https://github.com/ggerganov/llama.cpp/blob/master/examples/server/README.md#api-endpoints
if r.URL.Path == "/v1/chat/completions" {
// extracts the `model` from json body
pm.proxyChatRequest(w, r)
} else if r.URL.Path == "/v1/models" {
pm.listModels(w, r)
} else if r.URL.Path == "/logs" {
pm.streamLogs(w, r)
} else {
if pm.currentProcess != nil {
pm.currentProcess.ProxyRequest(w, r)
} else {
http.Error(w, "no strategy to handle request", http.StatusBadRequest)
}
}
}
func (pm *ProxyManager) streamLogs(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/plain")
w.Header().Set("Transfer-Encoding", "chunked")
w.Header().Set("X-Content-Type-Options", "nosniff")
ch := pm.logMonitor.Subscribe()
defer pm.logMonitor.Unsubscribe(ch)
notify := r.Context().Done()
flusher, ok := w.(http.Flusher)
if !ok {
http.Error(w, "Streaming unsupported", http.StatusInternalServerError)
return
}
skipHistory := r.URL.Query().Has("skip")
if !skipHistory {
// Send history first
history := pm.logMonitor.GetHistory()
if len(history) != 0 {
w.Write(history)
flusher.Flush()
}
}
if !r.URL.Query().Has("stream") {
return
}
// Stream new logs
for {
select {
case msg := <-ch:
w.Write(msg)
flusher.Flush()
case <-notify:
return
}
}
}
func (pm *ProxyManager) listModels(w http.ResponseWriter, _ *http.Request) {
data := []interface{}{}
for id := range pm.config.Models {
data = append(data, map[string]interface{}{
"id": id,
"object": "model",
"created": time.Now().Unix(),
"owned_by": "llama-swap",
})
}
// Set the Content-Type header to application/json
w.Header().Set("Content-Type", "application/json")
// Encode the data as JSON and write it to the response writer
if err := json.NewEncoder(w).Encode(map[string]interface{}{"data": data}); err != nil {
http.Error(w, "Error encoding JSON", http.StatusInternalServerError)
return
}
}
func (pm *ProxyManager) swapModel(requestedModel string) error {
pm.Lock()
defer pm.Unlock()
// find the model configuration matching requestedModel
modelConfig, modelID, found := pm.config.FindConfig(requestedModel)
if !found {
return fmt.Errorf("could not find configuration for %s", requestedModel)
}
// do nothing as it's already the correct process
if pm.currentProcess != nil {
if pm.currentProcess.ID == modelID {
return nil
} else {
pm.currentProcess.Stop()
}
}
pm.currentProcess = NewProcess(modelID, modelConfig, pm.logMonitor)
return pm.currentProcess.Start(pm.config.HealthCheckTimeout)
}
func (pm *ProxyManager) proxyChatRequest(w http.ResponseWriter, r *http.Request) {
bodyBytes, err := io.ReadAll(r.Body)
if err != nil {
http.Error(w, "Invalid JSON", http.StatusBadRequest)
return
}
var requestBody map[string]interface{}
if err := json.Unmarshal(bodyBytes, &requestBody); err != nil {
http.Error(w, "Invalid JSON", http.StatusBadRequest)
return
}
model, ok := requestBody["model"].(string)
if !ok {
http.Error(w, "Missing or invalid 'model' key", http.StatusBadRequest)
return
}
if err := pm.swapModel(model); err != nil {
http.Error(w, fmt.Sprintf("unable to swap to model, %s", err.Error()), http.StatusNotFound)
return
}
r.Body = io.NopCloser(bytes.NewBuffer(bodyBytes))
pm.currentProcess.ProxyRequest(w, r)
}