add nex protocol support

1 files changed, 91 insertions, 0 deletions

diff --git a/nex/serve.go b/nex/serve.go
new file mode 100644
index 0000000..7e103e3
--- /dev/null
+++ b/nex/serve.go
@@ -0,0 +1,91 @@
+package nex
+
+import (
+	"bytes"
+	"context"
+	"crypto/tls"
+	"fmt"
+	"io"
+	"net"
+
+	"tildegit.org/tjp/sliderule/internal"
+	"tildegit.org/tjp/sliderule/internal/types"
+	"tildegit.org/tjp/sliderule/logging"
+)
+
+type nexServer struct {
+	internal.Server
+	handler types.Handler
+}
+
+func (ns nexServer) Protocol() string { return "NEX" }
+
+// NewServer builds a new nex server
+func NewServer(
+	ctx context.Context,
+	hostname string,
+	network string,
+	address string,
+	handler types.Handler,
+	baseLog logging.Logger,
+) (types.Server, error) {
+	ns := &nexServer{handler: handler}
+
+	hostname = internal.JoinDefaultPort(hostname, "1900")
+	address = internal.JoinDefaultPort(address, "1900")
+
+	var err error
+	ns.Server, err = internal.NewServer(ctx, hostname, network, address, baseLog, ns.handleConn)
+	if err != nil {
+		return nil, err
+	}
+
+	return ns, err
+}
+
+func NewTLSServer(
+	ctx context.Context,
+	hostname string,
+	network string,
+	address string,
+	handler types.Handler,
+	baseLog logging.Logger,
+	tlsConfig *tls.Config,
+) (types.Server, error) {
+	ns, err := NewServer(ctx, hostname, network, address, handler, baseLog)
+	if err != nil {
+		return nil, err
+	}
+
+	ns.(*nexServer).Listener = tls.NewListener(ns.(*nexServer).Listener, tlsConfig)
+	return ns, nil
+}
+
+func (ns *nexServer) handleConn(conn net.Conn) {
+	request, err := ParseRequest(conn)
+	if err != nil {
+		_, _ = fmt.Fprint(conn, err.Error()+"\n")
+	}
+
+	request.Server = ns
+	request.RemoteAddr = conn.RemoteAddr()
+
+	if tlsconn, ok := conn.(*tls.Conn); ok {
+		state := tlsconn.ConnectionState()
+		request.TLSState = &state
+	}
+
+	defer func() {
+		if r := recover(); r != nil {
+			_ = ns.LogError("msg", "panic in handler", "err", r)
+			_, _ = fmt.Fprint(conn, "Error handling request.\n")
+		}
+	}()
+	response := ns.handler.Handle(ns.Ctx, request)
+	if response == nil {
+		response = Response(bytes.NewBufferString("Document not found."))
+	}
+
+	defer response.Close()
+	_, _ = io.Copy(conn, response.Body)
+}