fix(chaincmd): skip non json in JSONEnsuredBytes (#4540)

changelog.md

@@ -58,6 +58,7 @@
 - [#4091](https://github.com/ignite/cli/pull/4091) Fix race conditions in the plugin logic
 - [#4128](https://github.com/ignite/cli/pull/4128) Check for duplicate proto fields in config
 - [#4402](https://github.com/ignite/cli/pull/4402) Fix gentx parser into the cosmosutil package
+- [#4540](https://github.com/ignite/cli/pull/4540) Skip logs / gibberish when parsing commands outputs
 
 ## [`v28.8.0`](https://github.com/ignite/cli/releases/tag/v28.8.0)
 

ignite/pkg/chaincmd/runner/runner.go

@@ -6,6 +6,7 @@ import (
 	"context"
 	"encoding/json"
 	"io"
+	"strings"
 
 	"sigs.k8s.io/yaml"
 
@@ -145,12 +146,44 @@ type buffer struct {
 func (b *buffer) JSONEnsuredBytes() ([]byte, error) {
 	bz := b.Bytes()
 
-	var out interface{}
+	// check for valid json
+	startIndex := strings.IndexAny(string(bz), "{[")
+	if startIndex >= 0 {
+		// check if we need to find the matching closing bracket
+		opening := bz[startIndex]
+		var closing byte
+		if opening == '{' {
+			closing = '}'
+		} else {
+			closing = ']'
+		}
+
+		// look for the last matching closing bracket
+		endIndex := bytes.LastIndexByte(bz, closing)
+		if endIndex > startIndex {
+			// extract what appears to be valid JSON
+			bz = bz[startIndex : endIndex+1]
+
+			// verify it's actually valid JSON
+			var jsonTest any
+			if err := json.Unmarshal(bz, &jsonTest); err == nil {
+				return bz, nil
+			}
+		}
+	}
 
+	// fallback to yaml parsing
+	var out any
 	if err := yaml.Unmarshal(bz, &out); err == nil {
 		return yaml.YAMLToJSON(bz)
 	}
 
+	// if neither JSON nor YAML parsing succeeded, return the original bytes
+	// starting from the first opening brace if found, or the entire buffer
+	if startIndex >= 0 {
+		return bz[startIndex:], nil
+	}
+
 	return bz, nil
 }