Basic communication with lsp server

internal/lsp/server.go

@@ -0,0 +1,212 @@
+package lsp
+
+import (
+	"bufio"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"os/exec"
+	"strconv"
+	"strings"
+
+	"github.com/sourcegraph/go-lsp"
+	"github.com/zyedidia/micro/v2/internal/util"
+)
+
+var ActiveServers map[string]*Server
+
+func init() {
+	ActiveServers = make(map[string]*Server)
+}
+
+type Server struct {
+	cmd          *exec.Cmd
+	stdin        io.WriteCloser
+	stdout       *bufio.Reader
+	language     *Language
+	capabilities lsp.ServerCapabilities
+}
+
+type RPCMessage struct {
+	RPCVersion string      `json:"jsonrpc"`
+	ID         int         `json:"id"`
+	Method     string      `json:"method"`
+	Params     interface{} `json:"params"`
+}
+
+type RPCInit struct {
+	RPCVersion string               `json:"jsonrpc"`
+	ID         int                  `json:"id"`
+	Result     lsp.InitializeResult `json:"result"`
+}
+
+func StartServer(l Language) (*Server, error) {
+	c := exec.Command(l.Command, l.Args...)
+
+	log.Println("Running", l.Command, l.Args)
+
+	stdin, err := c.StdinPipe()
+	if err != nil {
+		return nil, err
+	}
+
+	stdout, err := c.StdoutPipe()
+	if err != nil {
+		return nil, err
+	}
+
+	err = c.Start()
+	if err != nil {
+		return nil, err
+	}
+
+	s := new(Server)
+	s.cmd = c
+	s.stdin = stdin
+	s.stdout = bufio.NewReader(stdout)
+	s.language = &l
+
+	// ActiveServers[l.Command] = s
+
+	return s, nil
+}
+
+func (s *Server) Initialize(directory string) error {
+	params := lsp.InitializeParams{
+		ProcessID: os.Getpid(),
+		RootURI:   lsp.DocumentURI("file://" + directory),
+		ClientInfo: lsp.ClientInfo{
+			Name:    "micro",
+			Version: util.Version,
+		},
+		Trace: "off",
+		Capabilities: lsp.ClientCapabilities{
+			Workspace: lsp.WorkspaceClientCapabilities{
+				WorkspaceEdit: struct {
+					DocumentChanges    bool     `json:"documentChanges,omitempty"`
+					ResourceOperations []string `json:"resourceOperations,omitempty"`
+				}{
+					DocumentChanges:    true,
+					ResourceOperations: []string{"create", "rename", "delete"},
+				},
+				ApplyEdit: true,
+			},
+			TextDocument: lsp.TextDocumentClientCapabilities{
+				Formatting: &struct {
+					DynamicRegistration bool `json:"dynamicRegistration,omitempty"`
+				}{
+					DynamicRegistration: true,
+				},
+				Completion: struct {
+					CompletionItem struct {
+						DocumentationFormat []lsp.DocumentationFormat `json:"documentationFormat,omitempty"`
+						SnippetSupport      bool                      `json:"snippetSupport,omitempty"`
+					} `json:"completionItem,omitempty"`
+
+					CompletionItemKind struct {
+						ValueSet []lsp.CompletionItemKind `json:"valueSet,omitempty"`
+					} `json:"completionItemKind,omitempty"`
+
+					ContextSupport bool `json:"contextSupport,omitempty"`
+				}{
+					CompletionItem: struct {
+						DocumentationFormat []lsp.DocumentationFormat `json:"documentationFormat,omitempty"`
+						SnippetSupport      bool                      `json:"snippetSupport,omitempty"`
+					}{
+						DocumentationFormat: []lsp.DocumentationFormat{lsp.DFPlainText},
+						SnippetSupport:      false,
+					},
+					ContextSupport: false,
+				},
+			},
+			Window: lsp.WindowClientCapabilities{
+				WorkDoneProgress: false,
+			},
+			Experimental: nil,
+		},
+	}
+
+	resp, err := s.SendMessage("initialize", params)
+	if err != nil {
+		return err
+	}
+
+	// todo parse capabilities
+	log.Println("Received", string(resp))
+
+	var r RPCInit
+	err = json.Unmarshal(resp, &r)
+	if err != nil {
+		return err
+	}
+
+	fmt.Println(r)
+	s.capabilities = r.Result.Capabilities
+	fmt.Println(s.capabilities)
+
+	_, err = s.SendMessage("initialized", struct{}{})
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (s *Server) SendMessage(method string, params interface{}) ([]byte, error) {
+	m := RPCMessage{
+		RPCVersion: "2.0",
+		ID:         os.Getpid(),
+		Method:     method,
+		Params:     params,
+	}
+
+	msg, err := json.Marshal(m)
+	if err != nil {
+		return nil, err
+	}
+
+	msg = append(msg, '\r', '\n')
+
+	header := []byte("Content-Length: " + strconv.Itoa(len(msg)) + "\r\n\r\n")
+	msg = append(header, msg...)
+
+	log.Println("Sending", string(msg))
+
+	s.stdin.Write(msg)
+
+	n := -1
+	for {
+		b, err := s.stdout.ReadBytes('\n')
+		if err != nil {
+			return nil, err
+		}
+		headerline := strings.TrimSpace(string(b))
+		if len(headerline) == 0 {
+			break
+		}
+		if strings.HasPrefix(headerline, "Content-Length:") {
+			split := strings.Split(headerline, ":")
+			if len(split) <= 1 {
+				break
+			}
+			n, err = strconv.Atoi(strings.TrimSpace(split[1]))
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	if n <= 0 {
+		return []byte{}, nil
+	}
+
+	bytes := make([]byte, n)
+	_, err = s.stdout.Read(bytes)
+	if err != nil {
+		return nil, err
+	}
+
+	return bytes, nil
+}