feat: informative error message

cmd/envd/main.go

@@ -21,6 +21,7 @@ import (
 	"github.com/cockroachdb/errors"
 	"github.com/spf13/viper"
 	"github.com/urfave/cli/v2"
+	"go.starlark.net/resolve"
 	"go.starlark.net/starlark"
 	"go.starlark.net/syntax"
 
@@ -44,18 +45,20 @@ func handleErr(err error) {
 	}
 
 	if viper.GetBool(flag.FlagDebug) {
-		fmt.Fprintf(os.Stderr, "error: %v\n", err)
+		fmt.Fprintf(os.Stderr, "error: %+v\n", err)
 	}
 
-	rootCause := errors.Cause(err)
 	var evalErr *starlark.EvalError
 	var syntaxErr *syntax.Error
+	var resolveErr resolve.ErrorList
 	if ok := errors.As(err, &evalErr); ok {
 		fmt.Fprintln(os.Stderr, evalErr.Backtrace())
 	} else if ok := errors.As(err, &syntaxErr); ok {
 		fmt.Fprintln(os.Stderr, syntaxErr)
+	} else if ok := errors.As(err, &resolveErr); ok {
+		fmt.Fprintf(os.Stderr, "%+v\n", resolveErr)
 	} else {
-		fmt.Fprintf(os.Stderr, "error: %v\n", rootCause)
+		fmt.Fprintf(os.Stderr, "error: %v\n", errors.Cause(err))
 	}
 	os.Exit(1)
 }

pkg/builder/builder.go

@@ -16,6 +16,7 @@ package builder
 
 import (
 	"context"
+	"fmt"
 	"io"
 	"os"
 	"path/filepath"
@@ -72,6 +73,15 @@ type Options struct {
 	UseHTTPProxy bool
 }
 
+type BuildkitdErr struct {
+	err error
+}
+
+func (e *BuildkitdErr) Error() string {
+	return e.err.Error()
+}
+func (e *BuildkitdErr) Format(s fmt.State, verb rune) { errors.FormatError(e, s, verb) }
+
 type generalBuilder struct {
 	Options
 	manifestCodeHash string
@@ -280,7 +290,8 @@ func (b generalBuilder) build(ctx context.Context, pw progresswriter.Writer) err
 				}
 				_, err := b.Client.Build(ctx, solveOpt, "envd", b.BuildFunc(), pw.Status())
 				if err != nil {
-					err = errors.Wrap(err, "failed to solve LLB")
+					err = errors.Wrap(&BuildkitdErr{err: err}, "Buildkit error")
+					logrus.Errorf("%+v", err)
 					return err
 				}
 				b.logger.Debug("llb def is solved successfully")

pkg/lang/frontend/starlark/config/config.go

@@ -20,6 +20,7 @@ import (
 	"go.starlark.net/starlark"
 	"go.starlark.net/starlarkstruct"
 
+	"github.com/tensorchord/envd/pkg/lang/frontend/starlark/starlarkutils"
 	"github.com/tensorchord/envd/pkg/lang/ir"
 )
 
@@ -202,11 +203,9 @@ func ruleFuncEntrypoint(thread *starlark.Thread, _ *starlark.Builtin,
 		return nil, err
 	}
 
-	argList := []string{}
-	if argv != nil {
-		for i := 0; i < argv.Len(); i++ {
-			argList = append(argList, argv.Index(i).(starlark.String).GoString())
-		}
+	argList, err := starlarkutils.ToStringSlice(argv)
+	if err != nil {
+		return nil, err
 	}
 
 	logger.Debugf("user defined entrypoints: {%s}\n", argList)

pkg/lang/frontend/starlark/install/install.go

@@ -20,6 +20,7 @@ import (
 	"go.starlark.net/starlark"
 	"go.starlark.net/starlarkstruct"
 
+	"github.com/tensorchord/envd/pkg/lang/frontend/starlark/starlarkutils"
 	"github.com/tensorchord/envd/pkg/lang/ir"
 )
 
@@ -51,26 +52,22 @@ func ruleFuncPyPIPackage(thread *starlark.Thread, _ *starlark.Builtin,
 		return nil, err
 	}
 
-	nameList := []string{}
-	if name != nil {
-		for i := 0; i < name.Len(); i++ {
-			nameList = append(nameList, name.Index(i).(starlark.String).GoString())
-		}
+	nameList, err := starlarkutils.ToStringSlice(name)
+	if err != nil {
+		return nil, err
 	}
 
 	requirementsFileStr := requirementsFile.GoString()
 
-	localWheels := []string{}
-	if wheels != nil {
-		for i := 0; i < wheels.Len(); i++ {
-			localWheels = append(localWheels, wheels.Index(i).(starlark.String).GoString())
-		}
+	localWheels, err := starlarkutils.ToStringSlice(wheels)
+	if err != nil {
+		return nil, err
 	}
 
 	logger.Debugf("rule `%s` is invoked, name=%v, requirements=%s, local_wheels=%s",
 		rulePyPIPackage, nameList, requirementsFileStr, localWheels)
 
-	err := ir.PyPIPackage(nameList, requirementsFileStr, localWheels)
+	err = ir.PyPIPackage(nameList, requirementsFileStr, localWheels)
 	return starlark.None, err
 }
 
@@ -83,11 +80,9 @@ func ruleFuncRPackage(thread *starlark.Thread, _ *starlark.Builtin,
 		return nil, err
 	}
 
-	nameList := []string{}
-	if name != nil {
-		for i := 0; i < name.Len(); i++ {
-			nameList = append(nameList, name.Index(i).(starlark.String).GoString())
-		}
+	nameList, err := starlarkutils.ToStringSlice(name)
+	if err != nil {
+		return nil, err
 	}
 
 	logger.Debugf("rule `%s` is invoked, name=%v", ruleRPackage, nameList)
@@ -105,13 +100,10 @@ func ruleFuncJulia(thread *starlark.Thread, _ *starlark.Builtin,
 		return nil, err
 	}
 
-	nameList := []string{}
-	if name != nil {
-		for i := 0; i < name.Len(); i++ {
-			nameList = append(nameList, name.Index(i).(starlark.String).GoString())
-		}
+	nameList, err := starlarkutils.ToStringSlice(name)
+	if err != nil {
+		return nil, err
 	}
-
 	logger.Debugf("rule `%s` is invoked, name=%v", ruleJulia, nameList)
 	ir.JuliaPackage(nameList)
 
@@ -127,11 +119,9 @@ func ruleFuncSystemPackage(thread *starlark.Thread, _ *starlark.Builtin,
 		return nil, err
 	}
 
-	nameList := []string{}
-	if name != nil {
-		for i := 0; i < name.Len(); i++ {
-			nameList = append(nameList, name.Index(i).(starlark.String).GoString())
-		}
+	nameList, err := starlarkutils.ToStringSlice(name)
+	if err != nil {
+		return nil, err
 	}
 
 	logger.Debugf("rule `%s` is invoked, name=%v", ruleSystemPackage, nameList)
@@ -168,11 +158,9 @@ func ruleFuncVSCode(thread *starlark.Thread, _ *starlark.Builtin,
 		return nil, err
 	}
 
-	pluginList := []string{}
-	if plugins != nil {
-		for i := 0; i < plugins.Len(); i++ {
-			pluginList = append(pluginList, plugins.Index(i).(starlark.String).GoString())
-		}
+	pluginList, err := starlarkutils.ToStringSlice(plugins)
+	if err != nil {
+		return nil, err
 	}
 
 	logger.Debugf("rule `%s` is invoked, plugins=%v", ruleVSCode, pluginList)
@@ -193,19 +181,16 @@ func ruleFuncConda(thread *starlark.Thread, _ *starlark.Builtin,
 		return nil, err
 	}
 
-	nameList := []string{}
-	if name != nil {
-		for i := 0; i < name.Len(); i++ {
-			nameList = append(nameList, name.Index(i).(starlark.String).GoString())
-		}
+	nameList, err := starlarkutils.ToStringSlice(name)
+	if err != nil {
+		return nil, err
 	}
 
-	channelList := []string{}
-	if channel != nil {
-		for i := 0; i < channel.Len(); i++ {
-			channelList = append(channelList, channel.Index(i).(starlark.String).GoString())
-		}
+	channelList, err := starlarkutils.ToStringSlice(channel)
+	if err != nil {
+		return nil, err
 	}
+
 	envFileStr := envFile.GoString()
 	if envFileStr != "" {
 

pkg/lang/frontend/starlark/starlarkutils/stringslice.go

@@ -0,0 +1,38 @@
+// Copyright 2022 The envd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package starlarkutils
+
+import (
+	"github.com/cockroachdb/errors"
+
+	"go.starlark.net/starlark"
+)
+
+func ToStringSlice(v *starlark.List) ([]string, error) {
+	if v == nil {
+		return []string{}, nil
+	}
+
+	s := []string{}
+	for i := 0; i < v.Len(); i++ {
+		str, ok := starlark.AsString(v.Index(i))
+		if !ok {
+			return nil, errors.Newf("Conversion failed, expect string type, but got %s as %s", v.Index(i), v.Index(i).Type())
+		}
+		s = append(s, str)
+	}
+
+	return s, nil
+}

pkg/lang/frontend/starlark/universe/universe.go

@@ -22,6 +22,7 @@ import (
 	"go.starlark.net/starlarkstruct"
 
 	"github.com/tensorchord/envd/pkg/lang/frontend/starlark/builtin"
+	"github.com/tensorchord/envd/pkg/lang/frontend/starlark/starlarkutils"
 	"github.com/tensorchord/envd/pkg/lang/ir"
 )
 
@@ -68,11 +69,9 @@ func ruleFuncRun(thread *starlark.Thread, _ *starlark.Builtin,
 		return nil, err
 	}
 
-	goCommands := []string{}
-	if commands != nil {
-		for i := 0; i < commands.Len(); i++ {
-			goCommands = append(goCommands, commands.Index(i).(starlark.String).GoString())
-		}
+	goCommands, err := starlarkutils.ToStringSlice(commands)
+	if err != nil {
+		return nil, err
 	}
 
 	logger.Debugf("rule `%s` is invoked, commands=%v", ruleRun, goCommands)