feat: auto env setup

lang/cxx/lib.go

@@ -15,6 +15,7 @@
 package cxx
 
 import (
+	"fmt"
 	"time"
 
 	"github.com/cloudwego/abcoder/lang/uniast"
@@ -23,6 +24,10 @@ import (
 
 const MaxWaitDuration = 5 * time.Minute
 
+func InstallLanguageServer() (string, error) {
+	return "", fmt.Errorf("please install clangd-18 manually. See https://releases.llvm.org/ (clangd is in clang-extra)")
+}
+
 func GetDefaultLSP() (lang uniast.Language, name string) {
 	return uniast.Cxx, "clangd-18"
 }

lang/parse.go

@@ -20,7 +20,6 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"github.com/cloudwego/abcoder/lang/register"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -33,6 +32,7 @@ import (
 	"github.com/cloudwego/abcoder/lang/log"
 	"github.com/cloudwego/abcoder/lang/lsp"
 	"github.com/cloudwego/abcoder/lang/python"
+	"github.com/cloudwego/abcoder/lang/register"
 	"github.com/cloudwego/abcoder/lang/rust"
 	"github.com/cloudwego/abcoder/lang/uniast"
 )
@@ -138,40 +138,63 @@ func checkRepoPath(repoPath string, language uniast.Language) (openfile string,
 }
 
 func checkLSP(language uniast.Language, lspPath string, args ParseOptions) (l uniast.Language, s string, err error) {
-	switch language {
-	case uniast.Rust:
-		l, s = rust.GetDefaultLSP()
-	case uniast.Cxx:
-		l, s = cxx.GetDefaultLSP()
-	case uniast.Python:
-		l, s = python.GetDefaultLSP()
-	case uniast.Java:
-		l, s = java.GetDefaultLSP(args.LspOptions)
-	case uniast.Golang:
-		l = uniast.Golang
-		s = ""
-		if _, err := exec.LookPath("go"); err != nil {
-			if _, err := os.Stat(lspPath); os.IsNotExist(err) {
-				log.Error("Go compiler not found, please make it excutable!\n", lspPath)
-				return uniast.Unknown, "", err
+	if lspPath != "" {
+		// designated LSP
+		l = language
+		s = lspPath
+	} else {
+		// default LSP
+		switch language {
+		case uniast.Rust:
+			l, s = rust.GetDefaultLSP()
+		case uniast.Cxx:
+			l, s = cxx.GetDefaultLSP()
+		case uniast.Python:
+			l, s = python.GetDefaultLSP()
+		case uniast.Java:
+			l, s = java.GetDefaultLSP(args.LspOptions)
+		case uniast.Golang:
+			if _, err := exec.LookPath("go"); err != nil {
+				if _, err := os.Stat(lspPath); os.IsNotExist(err) {
+					log.Error("Go compiler not found, please make it excutable!\n", lspPath)
+					return uniast.Unknown, "", err
+				}
 			}
+			return uniast.Golang, "", nil
+		default:
+			return uniast.Unknown, "", fmt.Errorf("unsupported language: %s", language)
 		}
-		return
-	default:
-		return uniast.Unknown, "", fmt.Errorf("unsupported language: %s", language)
 	}
-	// check if lsp excutable
-	if lspPath != "" {
-		if _, err := exec.LookPath(lspPath); err != nil {
-			if _, err := os.Stat(lspPath); os.IsNotExist(err) {
-				log.Error("Language server %s not found, please make it excutable!\n", lspPath)
-				return uniast.Unknown, "", err
-			}
+
+	// lsp already installed
+	if absLspPath, err := exec.LookPath(s); err == nil {
+		return l, absLspPath, nil
+	}
+
+	// install the lsp.
+	log.Error("Language server %s not found. Trying to auto install.\n", s)
+	s, err = installLanguageServer(language)
+	if err == nil {
+		if absLspPath, err := exec.LookPath(s); err == nil {
+			log.Error("Auto installation ok. lspPath=%s.", absLspPath)
+			return l, absLspPath, nil
 		}
-		s = lspPath
 	}
 
-	return
+	// install failed or broken (lsp not in PATH)
+	log.Info("Failed to install language server %s: %+w.\n", s, err)
+	return uniast.Unknown, "", err
+}
+
+func installLanguageServer(language uniast.Language) (string, error) {
+	switch language {
+	case uniast.Cxx:
+		return cxx.InstallLanguageServer()
+	case uniast.Python:
+		return python.InstallLanguageServer()
+	default:
+		return "", fmt.Errorf("auto installation not supported for language: %s", language)
+	}
 }
 
 func collectSymbol(ctx context.Context, cli *lsp.LSPClient, repoPath string, opts collect.CollectOption) (repo *uniast.Repository, err error) {

lang/python/lib.go

@@ -15,16 +15,82 @@
 package python
 
 import (
+	"fmt"
+	"os"
+	"os/exec"
+	"regexp"
+	"strconv"
+	"strings"
 	"time"
 
+	"github.com/cloudwego/abcoder/lang/log"
 	"github.com/cloudwego/abcoder/lang/uniast"
 	"github.com/cloudwego/abcoder/lang/utils"
 )
 
 const MaxWaitDuration = 5 * time.Second
+const lspName = "pylsp"
+
+func CheckPythonVersion() error {
+	// Check python3 command availability and get version.
+	output, err := exec.Command("python3", "--version").CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("python3 not found: %w. Do you have it installed? Or is it `python` but not aliased?", err)
+	}
+
+	// The regex is corrected to handle a capital 'P' and correctly capture the minor version.
+	format := `^Python 3\.(\d+)\..*$`
+	ptn := regexp.MustCompile(format)
+	matches := ptn.FindStringSubmatch(strings.TrimSpace(string(output)))
+	if len(matches) < 2 {
+		return fmt.Errorf("unexpected `python3 --version` output format: %q", output)
+	}
+	subver, err := strconv.ParseInt(matches[1], 10, 64)
+	if err != nil {
+		return fmt.Errorf("failed to parse python version from `python3 --version` output %q: %w", output, err)
+	}
+	if subver < 9 {
+		return fmt.Errorf("python version 3.%d is not supported; 3.9 or higher is required", subver)
+	}
+	return nil
+}
+
+func InstallLanguageServer() (string, error) {
+	if _, err := os.Stat("go.mod"); os.IsNotExist(err) {
+		log.Error("Auto installation requires working directory to be /path/to/abcoder/")
+		return "", fmt.Errorf("bad cwd")
+	}
+	if err := CheckPythonVersion(); err != nil {
+		log.Error("python version check failed: %v", err)
+		return "", err
+	}
+	// git submodule init
+	log.Error("Installing pylsp...")
+	if err := exec.Command("git", "submodule", "init").Run(); err != nil {
+		log.Error("git submodule init failed: %v", err)
+		return "", err
+	}
+	// git submodule update
+	if err := exec.Command("git", "submodule", "update").Run(); err != nil {
+		log.Error("git submodule update failed: %v", err)
+		return "", err
+	}
+	// python -m pip install -e projectRoot/pylsp
+	log.Error("Running `python3 -m pip install -e pylsp/` .\nThis might take some time, make sure the network connection is ok.")
+	if err := exec.Command("python3", "-m", "pip", "install", "-e", "pylsp/").Run(); err != nil {
+		log.Error("python -m pip install failed: %v", err)
+		return "", err
+	}
+	if err := exec.Command("pylsp", "--version").Run(); err != nil {
+		log.Error("`pylsp --version` failed: %v", err)
+		return "", err
+	}
+	log.Error("pylsp installed.")
+	return lspName, nil
+}
 
 func GetDefaultLSP() (lang uniast.Language, name string) {
-	return uniast.Python, "pylsp"
+	return uniast.Python, lspName
 }
 
 func CheckRepo(repo string) (string, time.Duration) {