fix: improved error msg (#936)

This is how the logs are printed now for exec


<img width="1443" alt="Screen Shot 2023-07-18 at 1 58 49 PM"
src="https://github.com/kurtosis-tech/kurtosis/assets/15133250/624700b8-7bb1-47c6-9d2c-0f79396f75ea">

core/server/api_container/server/startosis_engine/kurtosis_instruction/exec/exec.go

@@ -2,6 +2,7 @@ package exec
 
 import (
 	"context"
+	"fmt"
 	"github.com/kurtosis-tech/kurtosis/container-engine-lib/lib/backend_interface/objects/service"
 	"github.com/kurtosis-tech/kurtosis/core/server/api_container/server/service_network"
 	"github.com/kurtosis-tech/kurtosis/core/server/api_container/server/startosis_engine/kurtosis_starlark_framework"
@@ -14,6 +15,7 @@ import (
 	"github.com/kurtosis-tech/kurtosis/core/server/api_container/server/startosis_engine/startosis_validator"
 	"github.com/kurtosis-tech/stacktrace"
 	"go.starlark.net/starlark"
+	"strings"
 )
 
 var defaultAcceptableCodes = []int64{
@@ -161,8 +163,10 @@ func (builtin *ExecCapabilities) Execute(ctx context.Context, _ *builtin_argumen
 		return "", stacktrace.Propagate(err, "Error executing exec recipe")
 	}
 	if !builtin.skipCodeCheck && !builtin.isAcceptableCode(result) {
-		return "", stacktrace.NewError("Exec returned exit code '%v' that is not part of the acceptable status codes '%v', with output:\n%v", result["code"], builtin.acceptableCodes, result["output"])
+		errorMessage := fmt.Sprintf("Exec returned exit code '%v' that is not part of the acceptable status codes '%v', with output:", result["code"], builtin.acceptableCodes)
+		return "", stacktrace.NewError(formatErrorMessage(errorMessage, result["output"].String()))
 	}
+
 	builtin.runtimeValueStore.SetValue(builtin.resultUuid, result)
 	instructionResult := builtin.execRecipe.ResultMapToString(result)
 	return instructionResult, err
@@ -178,3 +182,9 @@ func (builtin *ExecCapabilities) isAcceptableCode(recipeResult map[string]starla
 	}
 	return isAcceptableCode
 }
+
+func formatErrorMessage(errorMessage string, errorFromExec string) string {
+	splitErrorMessageNewLine := strings.Split(errorFromExec, "\n")
+	reformattedErrorMessage := strings.Join(splitErrorMessageNewLine, "\n  ")
+	return fmt.Sprintf("%v\n  %v", errorMessage, reformattedErrorMessage)
+}

core/server/api_container/server/startosis_engine/kurtosis_instruction/tasks/run_python.go

@@ -312,9 +312,8 @@ func (builtin *RunPythonCapabilities) Execute(ctx context.Context, _ *builtin_ar
 
 	// throw an error as execution of the command failed
 	if runPythonExecutionResult.GetExitCode() != 0 {
-		return "", stacktrace.NewError(
-			"Python command: %q exited with code %d and output \n%v",
-			commandToRun, runPythonExecutionResult.GetExitCode(), runPythonExecutionResult.GetOutput())
+		errorMessage := fmt.Sprintf("Python command: %q exited with code %d and output", commandToRun, runPythonExecutionResult.GetExitCode())
+		return "", stacktrace.NewError(formatErrorMessage(errorMessage, runPythonExecutionResult.GetOutput()))
 	}
 
 	if builtin.fileArtifactNames != nil && builtin.pathToFileArtifacts != nil {

core/server/api_container/server/startosis_engine/kurtosis_instruction/tasks/run_sh.go

@@ -218,9 +218,8 @@ func (builtin *RunShCapabilities) Execute(ctx context.Context, _ *builtin_argume
 
 	// throw an error as execution of the command failed
 	if createDefaultDirectoryResult.GetExitCode() != 0 {
-		return "", stacktrace.NewError(
-			"Shell command: %q exited with code %d and output \n%v",
-			commandToRun, createDefaultDirectoryResult.GetExitCode(), createDefaultDirectoryResult.GetOutput())
+		errorMessage := fmt.Sprintf("Shell command: %q exited with code %d and output", commandToRun, createDefaultDirectoryResult.GetExitCode())
+		return "", stacktrace.NewError(formatErrorMessage(errorMessage, createDefaultDirectoryResult.GetOutput()))
 	}
 
 	if builtin.fileArtifactNames != nil && builtin.pathToFileArtifacts != nil {

core/server/api_container/server/startosis_engine/kurtosis_instruction/tasks/tasks_shared.go

@@ -254,3 +254,9 @@ func getServiceConfig(image string, filesArtifactExpansion *files_artifacts_expa
 		service_config.DefaultSubnetwork,
 	)
 }
+
+func formatErrorMessage(errorMessage string, errorFromExec string) string {
+	splitErrorMessageNewLine := strings.Split(errorFromExec, "\n")
+	reformattedErrorMessage := strings.Join(splitErrorMessageNewLine, "\n  ")
+	return fmt.Sprintf("%v\n  %v", errorMessage, reformattedErrorMessage)
+}