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940 lines (858 loc) · 26.4 KB
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/*---------------------------------------------------------------------------------------------
* Copyright (c) Microsoft Corporation. All rights reserved.
*--------------------------------------------------------------------------------------------*/
package copilot
import (
"bytes"
"context"
"encoding/base64"
"errors"
"fmt"
"io"
"net/http"
"strconv"
"strings"
"sync"
"github.com/coder/websocket"
"github.com/github/copilot-sdk/go/rpc"
)
// Hop-by-hop and length headers the transport recomputes; forwarding them
// verbatim corrupts the request.
var forbiddenRequestHeaders = map[string]struct{}{
"host": {},
"connection": {},
"content-length": {},
"transfer-encoding": {},
"keep-alive": {},
"upgrade": {},
"proxy-connection": {},
"te": {},
"trailer": {},
}
func isForbiddenRequestHeader(name string) bool {
lower := strings.ToLower(name)
if _, ok := forbiddenRequestHeaders[lower]; ok {
return true
}
return strings.HasPrefix(lower, "sec-websocket-")
}
var sharedHTTPTransport = func() http.RoundTripper {
t := http.DefaultTransport.(*http.Transport).Clone()
t.DisableCompression = true
return t
}()
// CopilotRequestContext is the per-request context handed to every
// [CopilotRequestHandler] seam.
type CopilotRequestContext struct {
RequestID string
SessionID string
AgentID string
ParentAgentID string
InteractionType string
// AgentInvocationID is the runtime-provided logical invocation identity,
// unchanged across physical retries. Nil when the runtime omits it.
AgentInvocationID *string
// Transport is "http" (covering plain HTTP and SSE) or "websocket".
Transport string
Method string
URL string
Headers http.Header
// body yields request body frames as they arrive from the runtime. It is
// unexported framework plumbing: the adapter drains it for HTTP requests
// and pumps it to [CopilotWebSocketHandler.SendRequestMessage] for
// WebSocket requests. Consumers read the HTTP body via the standard
// [http.Request] Body in a custom RoundTripper, or receive WebSocket frames
// via SendRequestMessage — never from this channel directly (doing so would
// race the adapter's pump goroutine and lose frames). The channel is closed
// when the body ends or the request is cancelled. For WebSocket requests
// each frame's Binary flag distinguishes a binary frame from a UTF-8 text
// frame; for HTTP it is always a body byte chunk.
body <-chan CopilotWebSocketMessage
// Context is cancelled when the runtime cancels this in-flight request.
Context context.Context
}
// CopilotWebSocketCloseStatus is the terminal status for a callback-owned
// WebSocket connection.
type CopilotWebSocketCloseStatus struct {
Description string
ErrorCode string
Err error
}
// CopilotWebSocketMessage is a single WebSocket frame exchanged through the
// handler seam. Binary distinguishes a binary frame from a UTF-8 text frame.
type CopilotWebSocketMessage struct {
Data []byte
Binary bool
// AgentInvocationID identifies this runtime request message's invocation,
// which may differ from the invocation that opened the connection.
// Nil when the runtime omits it, including upstream response messages.
AgentInvocationID *string
}
// Text decodes the frame payload as a UTF-8 string.
func (m CopilotWebSocketMessage) Text() string { return string(m.Data) }
// NewTextMessage creates a text-frame message from a UTF-8 string. Binary
// frames are constructed directly with CopilotWebSocketMessage{Data: ..., Binary: true}.
func NewTextMessage(text string) CopilotWebSocketMessage {
return CopilotWebSocketMessage{Data: []byte(text), Binary: false}
}
// CopilotRequestHandler is the idiomatic handler for intercepting or replacing
// LLM inference requests. HTTP requests are forwarded through Transport (an
// [http.RoundTripper]); supply a custom RoundTripper to mutate the request,
// post-process the response, or replace the call entirely. WebSocket requests
// are serviced by OpenWebSocket; supply one to return a custom handler.
//
// The default behaviour (both fields nil) transparently forwards HTTP through a
// shared transport and opens a forwarding WebSocket connection to the runtime's
// original URL.
type CopilotRequestHandler struct {
// Transport forwards HTTP requests. When nil a shared default transport is
// used. RoundTrip is called directly, so redirects are not followed.
Transport http.RoundTripper
// OpenWebSocket returns a per-connection WebSocket handler. When nil a
// transparent [CopilotWebSocketForwarder] to the request URL is opened.
OpenWebSocket func(ctx *CopilotRequestContext) (CopilotWebSocketHandler, error)
}
// WebSocketResponseWriter forwards upstream→runtime WebSocket messages back
// into the runtime response. A [CopilotWebSocketHandler] receives one in
// [CopilotWebSocketHandler.Open].
type WebSocketResponseWriter interface {
// SendText forwards an upstream text message to the runtime.
SendText(data []byte) error
// SendBinary forwards an upstream binary message to the runtime.
SendBinary(data []byte) error
}
// CopilotWebSocketHandler is a per-connection WebSocket handler returned by
// [CopilotRequestHandler.OpenWebSocket]. The default implementation is
// [CopilotWebSocketForwarder]; a full transport replacement implements
// this interface directly.
type CopilotWebSocketHandler interface {
// Open establishes the connection and starts forwarding upstream→runtime
// messages into resp. It must not block. ctx is cancelled on teardown.
Open(ctx context.Context, resp WebSocketResponseWriter) error
// SendRequestMessage forwards one runtime→upstream message.
SendRequestMessage(ctx context.Context, msg CopilotWebSocketMessage) error
// Done is closed when the upstream connection completes (closed or errored).
Done() <-chan struct{}
// Err returns the terminal error after Done is closed, or nil on clean close.
Err() error
// Close tears down the connection.
Close() error
}
// copilotContextKey is used to attach [CopilotRequestContext] to an
// [http.Request] so custom [http.RoundTripper] implementations can access
// metadata (e.g. SessionID and AgentID) without additional parameters.
type copilotContextKey struct{}
// RequestContextFrom returns the [CopilotRequestContext] attached to an
// http.Request by the adapter, or nil if not present. Call this from a custom
// [http.RoundTripper] to access metadata such as SessionID and AgentID.
func RequestContextFrom(r *http.Request) *CopilotRequestContext {
v, _ := r.Context().Value(copilotContextKey{}).(*CopilotRequestContext)
return v
}
func (h *CopilotRequestHandler) handle(rctx *CopilotRequestContext, sink *responseSink) error {
if rctx.Transport == "websocket" {
return h.handleWebSocket(rctx, sink)
}
return h.handleHTTP(rctx, sink)
}
func (h *CopilotRequestHandler) roundTripper() http.RoundTripper {
if h.Transport != nil {
return h.Transport
}
return sharedHTTPTransport
}
func (h *CopilotRequestHandler) handleHTTP(rctx *CopilotRequestContext, sink *responseSink) error {
httpReq, err := buildHTTPRequest(rctx)
if err != nil {
return err
}
resp, err := h.roundTripper().RoundTrip(httpReq)
if err != nil {
return err
}
defer resp.Body.Close()
return streamResponseToSink(rctx.Context, resp, sink)
}
func buildHTTPRequest(rctx *CopilotRequestContext) (*http.Request, error) {
body := drainBody(rctx.body)
method := strings.ToUpper(rctx.Method)
var bodyReader io.Reader
if len(body) > 0 && method != http.MethodGet && method != http.MethodHead {
bodyReader = bytes.NewReader(body)
}
httpReq, err := http.NewRequestWithContext(rctx.Context, method, rctx.URL, bodyReader)
if err != nil {
return nil, err
}
// Attach rctx so custom RoundTripper implementations can read metadata
// (e.g. SessionID and AgentID) via [RequestContextFrom].
httpReq = httpReq.WithContext(context.WithValue(httpReq.Context(), copilotContextKey{}, rctx))
for name, values := range rctx.Headers {
if isForbiddenRequestHeader(name) {
continue
}
for _, v := range values {
httpReq.Header.Add(name, v)
}
}
return httpReq, nil
}
func drainBody(ch <-chan CopilotWebSocketMessage) []byte {
var buf bytes.Buffer
for frame := range ch {
buf.Write(frame.Data)
}
return buf.Bytes()
}
func streamResponseToSink(ctx context.Context, resp *http.Response, sink *responseSink) error {
if err := sink.start(resp.StatusCode, statusText(resp), cloneHeader(resp.Header)); err != nil {
return err
}
reader := newHTTPResponseReader(resp.Body)
defer reader.Close()
var chunk []byte
for {
ok, err := reader.nextChunk(ctx, &chunk)
if err != nil {
return err
}
if !ok {
return sink.end()
}
if err := sink.writeBinary(chunk); err != nil {
return err
}
}
}
func statusText(resp *http.Response) string {
return strings.TrimSpace(strings.TrimPrefix(resp.Status, strconv.Itoa(resp.StatusCode)))
}
func cloneHeader(h http.Header) http.Header {
out := http.Header{}
for k, vs := range h {
out[k] = append([]string(nil), vs...)
}
return out
}
func (h *CopilotRequestHandler) handleWebSocket(rctx *CopilotRequestContext, sink *responseSink) error {
var handler CopilotWebSocketHandler
var err error
if h.OpenWebSocket != nil {
handler, err = h.OpenWebSocket(rctx)
} else {
handler = NewCopilotWebSocketForwarder(rctx.URL, rctx.Headers)
}
if err != nil {
return err
}
writer := &wsResponseWriter{sink: sink}
// Emit the 101 upgrade head eagerly — the runtime gates connect_via_callback
// on receiving httpResponseStart/101 before sending request chunks; a lazy
// first-write start deadlocks until timeout.
if err := writer.start(); err != nil {
return err
}
if err := handler.Open(rctx.Context, writer); err != nil {
return writer.fail(err.Error(), "")
}
defer func() { _ = handler.Close() }()
clientDone := make(chan struct{})
go func() {
defer close(clientDone)
for {
select {
case frame, ok := <-rctx.body:
if !ok {
return
}
if err := handler.SendRequestMessage(rctx.Context, frame); err != nil {
return
}
case <-rctx.Context.Done():
return
}
}
}()
select {
case <-handler.Done():
if e := handler.Err(); e != nil {
return writer.fail(e.Error(), "")
}
return writer.end()
case <-clientDone:
_ = handler.Close()
<-handler.Done()
if e := handler.Err(); e != nil {
return writer.fail(e.Error(), "")
}
return writer.end()
case <-rctx.Context.Done():
return writer.fail("Request cancelled by runtime", "cancelled")
}
}
// wsResponseWriter serialises WebSocket response writes into the sink.
type wsResponseWriter struct {
mu sync.Mutex
sink *responseSink
started bool
completed bool
}
func (w *wsResponseWriter) start() error {
w.mu.Lock()
defer w.mu.Unlock()
if w.started {
return nil
}
w.started = true
return w.sink.start(101, "", http.Header{})
}
func (w *wsResponseWriter) SendText(data []byte) error {
w.mu.Lock()
defer w.mu.Unlock()
if w.completed {
return nil
}
return w.sink.writeText(data)
}
func (w *wsResponseWriter) SendBinary(data []byte) error {
w.mu.Lock()
defer w.mu.Unlock()
if w.completed {
return nil
}
return w.sink.writeBinary(data)
}
func (w *wsResponseWriter) end() error {
w.mu.Lock()
defer w.mu.Unlock()
if w.completed {
return nil
}
w.completed = true
return w.sink.end()
}
func (w *wsResponseWriter) fail(message string, code string) error {
w.mu.Lock()
defer w.mu.Unlock()
if w.completed {
return nil
}
w.completed = true
return w.sink.sinkError(message, code)
}
// CopilotWebSocketForwarder is the default [CopilotWebSocketHandler]:
// it dials the real upstream and runs a receive loop forwarding upstream→runtime
// messages. Set OnSendRequestMessage / OnSendResponseMessage to observe,
// transform, or drop messages in either direction.
type CopilotWebSocketForwarder struct {
URL string
Headers http.Header
// OnSendRequestMessage observes or transforms each runtime→upstream frame.
// The frame type (text vs binary) is available via the message's Binary
// field and may be changed in the returned message. Return nil to drop the
// frame.
OnSendRequestMessage func(msg CopilotWebSocketMessage) *CopilotWebSocketMessage
// OnSendResponseMessage observes or transforms each upstream→runtime frame.
// The frame type (text vs binary) is available via the message's Binary
// field and may be changed in the returned message. Return nil to drop the
// frame.
OnSendResponseMessage func(msg CopilotWebSocketMessage) *CopilotWebSocketMessage
conn *websocket.Conn
resp WebSocketResponseWriter
done chan struct{}
err error
closeOnce sync.Once
}
// NewCopilotWebSocketForwarder creates a forwarding handler targeting
// url with the given handshake headers.
func NewCopilotWebSocketForwarder(url string, headers http.Header) *CopilotWebSocketForwarder {
return &CopilotWebSocketForwarder{URL: url, Headers: headers, done: make(chan struct{})}
}
func (f *CopilotWebSocketForwarder) Open(ctx context.Context, resp WebSocketResponseWriter) error {
f.resp = resp
if f.done == nil {
f.done = make(chan struct{})
}
opts := &websocket.DialOptions{HTTPHeader: f.dialHeaders()}
conn, _, err := websocket.Dial(ctx, f.URL, opts)
if err != nil {
return err
}
conn.SetReadLimit(-1)
f.conn = conn
go f.receiveLoop(ctx)
return nil
}
func (f *CopilotWebSocketForwarder) dialHeaders() http.Header {
out := http.Header{}
for name, values := range f.Headers {
if isForbiddenRequestHeader(name) {
continue
}
for _, v := range values {
out.Add(name, v)
}
}
return out
}
func (f *CopilotWebSocketForwarder) receiveLoop(ctx context.Context) {
defer close(f.done)
for {
typ, data, err := f.conn.Read(ctx)
if err != nil {
if websocket.CloseStatus(err) == websocket.StatusNormalClosure || websocket.CloseStatus(err) == websocket.StatusGoingAway {
f.err = nil
} else if ctx.Err() != nil {
f.err = nil
} else {
f.err = err
}
return
}
out := CopilotWebSocketMessage{Data: data, Binary: typ == websocket.MessageBinary}
if f.OnSendResponseMessage != nil {
transformed := f.OnSendResponseMessage(out)
if transformed == nil {
continue
}
out = *transformed
}
if out.Binary {
_ = f.resp.SendBinary(out.Data)
} else {
_ = f.resp.SendText(out.Data)
}
}
}
func (f *CopilotWebSocketForwarder) SendRequestMessage(ctx context.Context, msg CopilotWebSocketMessage) error {
out := msg
if f.OnSendRequestMessage != nil {
transformed := f.OnSendRequestMessage(msg)
if transformed == nil {
return nil
}
out = *transformed
}
if f.conn == nil {
return nil
}
msgType := websocket.MessageText
if out.Binary {
msgType = websocket.MessageBinary
}
return f.conn.Write(ctx, msgType, out.Data)
}
func (f *CopilotWebSocketForwarder) Done() <-chan struct{} { return f.done }
func (f *CopilotWebSocketForwarder) Err() error { return f.err }
func (f *CopilotWebSocketForwarder) Close() error {
f.closeOnce.Do(func() {
if f.conn != nil {
_ = f.conn.Close(websocket.StatusNormalClosure, "")
}
})
return nil
}
// --- Internal adapter ---
// frameQueue is an unbounded FIFO of body frames, decoupling the RPC dispatch
// goroutine (which only pushes) from the consumer goroutine (which pops).
type frameQueue struct {
mu sync.Mutex
cond *sync.Cond
items []CopilotWebSocketMessage
done bool
}
func newFrameQueue() *frameQueue {
q := &frameQueue{}
q.cond = sync.NewCond(&q.mu)
return q
}
func (q *frameQueue) push(m CopilotWebSocketMessage) {
q.mu.Lock()
if !q.done {
q.items = append(q.items, m)
}
q.cond.Signal()
q.mu.Unlock()
}
func (q *frameQueue) close() {
q.mu.Lock()
q.done = true
q.cond.Broadcast()
q.mu.Unlock()
}
func (q *frameQueue) pop() (CopilotWebSocketMessage, bool) {
q.mu.Lock()
defer q.mu.Unlock()
for len(q.items) == 0 && !q.done {
q.cond.Wait()
}
if len(q.items) > 0 {
m := q.items[0]
q.items = q.items[1:]
return m, true
}
return CopilotWebSocketMessage{}, false
}
type pendingExchange struct {
mu sync.Mutex
queue *frameQueue
ctx context.Context
cancel context.CancelCauseFunc
started bool
finished bool
}
type copilotRequestAdapter struct {
handler *CopilotRequestHandler
getRPC func() *rpc.ServerLlmInferenceAPI
mu sync.Mutex
pending map[string]*pendingExchange
closed bool
connectionCtx context.Context
connectionCancel context.CancelCauseFunc
}
func newCopilotRequestAdapter(handler *CopilotRequestHandler, getRPC func() *rpc.ServerLlmInferenceAPI) *copilotRequestAdapter {
connectionCtx, connectionCancel := context.WithCancelCause(context.Background())
return &copilotRequestAdapter{
handler: handler,
getRPC: getRPC,
pending: make(map[string]*pendingExchange),
connectionCtx: connectionCtx,
connectionCancel: connectionCancel,
}
}
// getOrCreateExchange returns the exchange for requestID, allocating one if it
// does not yet exist. The runtime dispatches httpRequestStart and
// httpRequestChunk frames on separate goroutines (see jsonrpc2.handleRequest),
// so a body chunk — including the terminal end frame — can arrive before its
// start frame runs. Creating the exchange (and its buffering frameQueue) on
// first touch means those chunks are buffered rather than dropped, instead of
// hanging the body drain forever.
func (a *copilotRequestAdapter) getOrCreateExchange(requestID string) *pendingExchange {
a.mu.Lock()
defer a.mu.Unlock()
if exchange, ok := a.pending[requestID]; ok {
return exchange
}
ctx, cancel := context.WithCancelCause(a.connectionCtx)
exchange := &pendingExchange{queue: newFrameQueue(), ctx: ctx, cancel: cancel}
if a.closed {
exchange.queue.close()
return exchange
}
a.pending[requestID] = exchange
return exchange
}
func (a *copilotRequestAdapter) HttpRequestStart(params *rpc.LlmInferenceHTTPRequestStartRequest) (*rpc.LlmInferenceHTTPRequestStartResult, error) {
// Adopt any exchange a racing chunk already created — with its buffered
// body — rather than dropping those frames.
exchange := a.getOrCreateExchange(params.RequestID)
ctx := exchange.ctx
bodyCh := make(chan CopilotWebSocketMessage)
go func() {
defer close(bodyCh)
for {
m, ok := exchange.queue.pop()
if !ok {
return
}
select {
case bodyCh <- m:
case <-ctx.Done():
return
}
}
}()
transport := "http"
if params.Transport != nil {
transport = string(*params.Transport)
}
sessionID := ""
if params.SessionID != nil {
sessionID = *params.SessionID
}
headers := http.Header{}
for k, v := range params.Headers {
headers[k] = append([]string(nil), v...)
}
rctx := &CopilotRequestContext{
RequestID: params.RequestID,
SessionID: sessionID,
AgentID: stringOrEmpty(params.AgentID),
AgentInvocationID: params.AgentInvocationID,
ParentAgentID: stringOrEmpty(params.ParentAgentID),
InteractionType: stringOrEmpty(params.InteractionType),
Method: params.Method,
URL: params.URL,
Headers: headers,
Transport: transport,
body: bodyCh,
Context: ctx,
}
sink := &responseSink{requestID: params.RequestID, adapter: a, exchange: exchange}
go a.runHandler(rctx, sink, exchange)
return &rpc.LlmInferenceHTTPRequestStartResult{}, nil
}
func (a *copilotRequestAdapter) HttpRequestChunk(params *rpc.LlmInferenceHTTPRequestChunkRequest) (*rpc.LlmInferenceHTTPRequestChunkResult, error) {
// May arrive before the matching start frame (frames are dispatched on
// separate goroutines); get-or-create so the body is buffered, never lost.
exchange := a.getOrCreateExchange(params.RequestID)
a.routeChunk(exchange, params)
return &rpc.LlmInferenceHTTPRequestChunkResult{}, nil
}
func (a *copilotRequestAdapter) routeChunk(exchange *pendingExchange, params *rpc.LlmInferenceHTTPRequestChunkRequest) {
if params.Cancel != nil && *params.Cancel {
exchange.cancel(errRuntimeRequestCancelled)
exchange.queue.close()
return
}
if params.Data != "" {
binary := params.Binary != nil && *params.Binary
if data, err := decodeChunkData(params.Data, binary); err == nil {
exchange.queue.push(CopilotWebSocketMessage{
Data: data, Binary: binary, AgentInvocationID: params.AgentInvocationID,
})
}
}
if params.End != nil && *params.End {
exchange.queue.close()
}
}
func (a *copilotRequestAdapter) runHandler(rctx *CopilotRequestContext, sink *responseSink, exchange *pendingExchange) {
defer exchange.cancel(nil)
err := a.handler.handle(rctx, sink)
if err != nil {
cause := context.Cause(exchange.ctx)
if errors.Is(cause, errRuntimeRequestCancelled) {
a.finishCancelled(sink, exchange)
return
}
if cause != nil {
a.removePending(sink.requestID)
return
}
a.failViaSink(sink, exchange, err.Error())
return
}
cause := context.Cause(exchange.ctx)
if errors.Is(cause, errRuntimeRequestCancelled) {
a.finishCancelled(sink, exchange)
return
}
if cause != nil {
a.removePending(sink.requestID)
return
}
exchange.mu.Lock()
finished := exchange.finished
exchange.mu.Unlock()
if !finished {
a.failViaSink(sink, exchange, "CopilotRequestHandler returned without finalising the response")
}
}
func (a *copilotRequestAdapter) failViaSink(sink *responseSink, exchange *pendingExchange, message string) {
exchange.mu.Lock()
finished := exchange.finished
started := exchange.started
exchange.mu.Unlock()
if finished {
return
}
if !started {
_ = sink.start(502, "", http.Header{})
}
_ = sink.sinkError(message, "")
}
func (a *copilotRequestAdapter) finishCancelled(sink *responseSink, exchange *pendingExchange) {
exchange.mu.Lock()
finished := exchange.finished
started := exchange.started
exchange.mu.Unlock()
if finished {
return
}
if !started {
_ = sink.startWithContext(sink.adapter.connectionCtx, 499, "", http.Header{})
}
_ = sink.sinkError("Request cancelled by runtime", "cancelled")
}
func (a *copilotRequestAdapter) removePending(requestID string) {
a.mu.Lock()
delete(a.pending, requestID)
a.mu.Unlock()
}
var (
errRuntimeRequestCancelled = errors.New("request cancelled by runtime")
errRPCConnectionClosed = errors.New("RPC connection closed")
)
func (a *copilotRequestAdapter) close() {
a.mu.Lock()
if a.closed {
a.mu.Unlock()
return
}
a.closed = true
exchanges := make([]*pendingExchange, 0, len(a.pending))
for _, exchange := range a.pending {
exchanges = append(exchanges, exchange)
}
clear(a.pending)
a.mu.Unlock()
a.connectionCancel(errRPCConnectionClosed)
for _, exchange := range exchanges {
exchange.queue.close()
}
}
func stringOrEmpty(value *string) string {
if value == nil {
return ""
}
return *value
}
func decodeChunkData(data string, binary bool) ([]byte, error) {
if binary {
return base64.StdEncoding.DecodeString(data)
}
return []byte(data), nil
}
// responseSink writes response frames to the runtime via RPC.
type responseSink struct {
requestID string
adapter *copilotRequestAdapter
exchange *pendingExchange
}
func (s *responseSink) rpcAPI() (*rpc.ServerLlmInferenceAPI, error) {
r := s.adapter.getRPC()
if r == nil {
return nil, fmt.Errorf("CopilotRequestHandler response sink used after RPC connection closed")
}
return r, nil
}
func (s *responseSink) start(status int, statusTxt string, headers http.Header) error {
return s.startWithContext(s.exchange.ctx, status, statusTxt, headers)
}
func (s *responseSink) startWithContext(ctx context.Context, status int, statusTxt string, headers http.Header) error {
s.exchange.mu.Lock()
if s.exchange.started {
s.exchange.mu.Unlock()
return fmt.Errorf("CopilotRequestHandler response sink Start() called twice")
}
if s.exchange.finished {
s.exchange.mu.Unlock()
return fmt.Errorf("CopilotRequestHandler response sink already finished")
}
s.exchange.started = true
s.exchange.mu.Unlock()
api, err := s.rpcAPI()
if err != nil {
return err
}
var st *string
if statusTxt != "" {
st = &statusTxt
}
h := map[string][]string(headers)
if h == nil {
h = map[string][]string{}
}
result, err := api.HttpResponseStart(ctx, &rpc.LlmInferenceHTTPResponseStartRequest{
RequestID: s.requestID,
Status: int64(status),
StatusText: st,
Headers: h,
})
if err == nil && !result.Accepted {
return fmt.Errorf("llmInference.httpResponseStart was rejected")
}
return err
}
func (s *responseSink) writeText(data []byte) error {
return s.writeRaw(string(data), false)
}
func (s *responseSink) writeBinary(data []byte) error {
return s.writeRaw(base64.StdEncoding.EncodeToString(data), true)
}
func (s *responseSink) writeRaw(data string, binary bool) error {
s.exchange.mu.Lock()
started := s.exchange.started
finished := s.exchange.finished
s.exchange.mu.Unlock()
if !started {
return fmt.Errorf("CopilotRequestHandler response sink Write() called before Start()")
}
if finished {
return fmt.Errorf("CopilotRequestHandler response sink Write() called after End()/Error()")
}
api, err := s.rpcAPI()
if err != nil {
return err
}
end := false
chunk := &rpc.LlmInferenceHTTPResponseChunkRequest{
RequestID: s.requestID,
Data: data,
End: &end,
}
if binary {
b := true
chunk.Binary = &b
}
result, err := api.HttpResponseChunk(s.exchange.ctx, chunk)
if err == nil && !result.Accepted {
return fmt.Errorf("llmInference.httpResponseChunk was rejected")
}
return err
}
func (s *responseSink) end() error {
s.exchange.mu.Lock()
if s.exchange.finished {
s.exchange.mu.Unlock()
return nil
}
s.exchange.finished = true
s.exchange.mu.Unlock()
s.adapter.removePending(s.requestID)
api, err := s.rpcAPI()
if err != nil {
return err
}
end := true
result, err := api.HttpResponseChunk(s.exchange.ctx, &rpc.LlmInferenceHTTPResponseChunkRequest{
RequestID: s.requestID,
Data: "",
End: &end,
})
if err == nil && !result.Accepted {
return fmt.Errorf("llmInference.httpResponseChunk was rejected")
}
return err
}
func (s *responseSink) sinkError(message string, code string) error {
s.exchange.mu.Lock()
if s.exchange.finished {
s.exchange.mu.Unlock()
return nil
}
s.exchange.finished = true
s.exchange.mu.Unlock()
s.adapter.removePending(s.requestID)
api, err := s.rpcAPI()
if err != nil {
return err
}
end := true
chunkErr := &rpc.LlmInferenceHTTPResponseChunkError{Message: message}
if code != "" {
c := code
chunkErr.Code = &c
}
result, err := api.HttpResponseChunk(s.adapter.connectionCtx, &rpc.LlmInferenceHTTPResponseChunkRequest{
RequestID: s.requestID,
Data: "",
End: &end,
Error: chunkErr,
})
if err == nil && !result.Accepted {
return fmt.Errorf("llmInference.httpResponseChunk was rejected")
}
return err
}
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