merge files

Author: asmyasnikov

internal/cmd/engine_plugin_runner.go

@@ -1,13 +1,15 @@
-package cmd
+// This file runs a database-engine plugin as an external process (parse RPC over stdin/stdout).
+// It is used only by the plugin-engine generate path (runPluginQuerySet). Vet does not support plugin engines.
 
-// This file implements the plugin-**engine** path only (runPluginQuerySet).
-// When engine is not builtin, generate calls runPluginQuerySet: schema+query → engine plugin ParseRequest → compiler.Result → ProcessResult/codegen.
-// Codegen plugins are handled in generate.go/shim; this file is only for external database engines.
+package cmd
 
 import (
+	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strings"
 
@@ -18,9 +20,72 @@ import (
 	"github.com/sqlc-dev/sqlc/internal/source"
 	"github.com/sqlc-dev/sqlc/internal/sql/catalog"
 	"github.com/sqlc-dev/sqlc/internal/sql/sqlpath"
+	"google.golang.org/protobuf/proto"
+
+	"github.com/sqlc-dev/sqlc/internal/info"
 	pb "github.com/sqlc-dev/sqlc/pkg/engine"
 )
 
+// engineProcessRunner runs an engine plugin as an external process.
+type engineProcessRunner struct {
+	Cmd string
+	Dir string // Working directory for the plugin (config file directory)
+	Env []string
+}
+
+func newEngineProcessRunner(cmd, dir string, env []string) *engineProcessRunner {
+	return &engineProcessRunner{Cmd: cmd, Dir: dir, Env: env}
+}
+
+func (r *engineProcessRunner) invoke(ctx context.Context, method string, req, resp proto.Message) error {
+	stdin, err := proto.Marshal(req)
+	if err != nil {
+		return fmt.Errorf("failed to encode request: %w", err)
+	}
+
+	cmdParts := strings.Fields(r.Cmd)
+	if len(cmdParts) == 0 {
+		return fmt.Errorf("engine plugin not found: %s\n\nMake sure the plugin is installed and available in PATH.\nInstall with: go install <plugin-module>@latest", r.Cmd)
+	}
+
+	path, err := exec.LookPath(cmdParts[0])
+	if err != nil {
+		return fmt.Errorf("engine plugin not found: %s\n\nMake sure the plugin is installed and available in PATH.\nInstall with: go install <plugin-module>@latest", r.Cmd)
+	}
+
+	args := append(cmdParts[1:], method)
+	cmd := exec.CommandContext(ctx, path, args...)
+	cmd.Stdin = bytes.NewReader(stdin)
+	if r.Dir != "" {
+		cmd.Dir = r.Dir
+	}
+	cmd.Env = append(os.Environ(), fmt.Sprintf("SQLC_VERSION=%s", info.Version))
+
+	out, err := cmd.Output()
+	if err != nil {
+		stderr := err.Error()
+		var exit *exec.ExitError
+		if errors.As(err, &exit) {
+			stderr = string(exit.Stderr)
+		}
+		return fmt.Errorf("engine plugin error: %s", stderr)
+	}
+
+	if err := proto.Unmarshal(out, resp); err != nil {
+		return fmt.Errorf("failed to decode response: %w", err)
+	}
+	return nil
+}
+
+// parseRequest invokes the plugin's Parse RPC. Used by runPluginQuerySet.
+func (r *engineProcessRunner) parseRequest(ctx context.Context, req *pb.ParseRequest) (*pb.ParseResponse, error) {
+	resp := &pb.ParseResponse{}
+	if err := r.invoke(ctx, "parse", req, resp); err != nil {
+		return nil, err
+	}
+	return resp, nil
+}
+
 // defaultCommentSyntax is used when parsing query names from plugin-engine query files.
 var defaultCommentSyntax = metadata.CommentSyntax(source.CommentSyntax{Dash: true, SlashStar: true, Hash: false})