nixbuild/instantiateDrvPath: parse json

Author: alyraffauf

src/nixbuild.go

@@ -3,7 +3,6 @@ package main
 import (
 	"encoding/json"
 	"fmt"
-	"strings"
 )
 
 // model 'nix build --json' output.
@@ -84,12 +83,15 @@ func instantiateDrvPath(flake string, name string, builder string) (string, erro
 	drvExpr := expr + ".drvPath"
 
 	// Evaluate the .drv path locally
-	data, err := runJSON("nix", "eval", "--raw", drvExpr)
+	data, err := runJSON("nix", "eval", "--json", drvExpr)
 	if err != nil {
 		return "", fmt.Errorf("failed to evaluate drvPath for job '%s': %w", name, err)
 	}
 
-	drvPath := strings.TrimSpace(string(data))
+	var drvPath string
+	if err := json.Unmarshal(data, &drvPath); err != nil {
+		return "", fmt.Errorf("failed to parse JSON for job '%s': %w", name, err)
+	}
 
 	// Copy the .drv to the remote builder (if needed)
 	if builder != "localhost" {