fix(logql): Fix panic in json parsing when using empty array index (#14393)

This commit fixes a panic that occurs with the following json parser expression:

```
| json keys[""]
```

when the log line is the following:

```json
{"keys": ["a", "b", "c"]}
```

Signed-off-by: Christian Haudum <[email protected]>

Author: chaudum

go.mod

@@ -125,7 +125,7 @@ require (
 	github.com/efficientgo/core v1.0.0-rc.3
 	github.com/fsnotify/fsnotify v1.7.0
 	github.com/gogo/googleapis v1.4.1
-	github.com/grafana/jsonparser v0.0.0-20240425183733-ea80629e1a32
+	github.com/grafana/jsonparser v0.0.0-20241004153430-023329977675
 	github.com/grafana/loki/pkg/push v0.0.0-20240924133635-758364c7775f
 	github.com/hashicorp/golang-lru/v2 v2.0.7
 	github.com/hashicorp/raft v1.7.1

go.sum

@@ -1052,8 +1052,8 @@ github.com/grafana/gocql v0.0.0-20200605141915-ba5dc39ece85 h1:xLuzPoOzdfNb/RF/I
 github.com/grafana/gocql v0.0.0-20200605141915-ba5dc39ece85/go.mod h1:crI9WX6p0IhrqB+DqIUHulRW853PaNFf7o4UprV//3I=
 github.com/grafana/gomemcache v0.0.0-20240229205252-cd6a66d6fb56 h1:X8IKQ0wu40wpvYcKfBcc5T4QnhdQjUhtUtB/1CY89lE=
 github.com/grafana/gomemcache v0.0.0-20240229205252-cd6a66d6fb56/go.mod h1:PGk3RjYHpxMM8HFPhKKo+vve3DdlPUELZLSDEFehPuU=
-github.com/grafana/jsonparser v0.0.0-20240425183733-ea80629e1a32 h1:NznuPwItog+rwdVg8hAuGKP29ndRSzJAwhxKldkP8oQ=
-github.com/grafana/jsonparser v0.0.0-20240425183733-ea80629e1a32/go.mod h1:796sq+UcONnSlzA3RtlBZ+b/hrerkZXiEmO8oMjyRwY=
+github.com/grafana/jsonparser v0.0.0-20241004153430-023329977675 h1:U94jQ2TQr1m3HNyE8efSdyaBbDrdPaWImXyenuKZ/nw=
+github.com/grafana/jsonparser v0.0.0-20241004153430-023329977675/go.mod h1:796sq+UcONnSlzA3RtlBZ+b/hrerkZXiEmO8oMjyRwY=
 github.com/grafana/memberlist v0.3.1-0.20220714140823-09ffed8adbbe h1:yIXAAbLswn7VNWBIvM71O2QsgfgW9fRXZNR0DXe6pDU=
 github.com/grafana/memberlist v0.3.1-0.20220714140823-09ffed8adbbe/go.mod h1:MS2lj3INKhZjWNqd3N0m3J+Jxf3DAOnAH9VT3Sh9MUE=
 github.com/grafana/pyroscope-go/godeltaprof v0.1.8 h1:iwOtYXeeVSAeYefJNaxDytgjKtUuKQbJqgAIjlnicKg=

pkg/logql/log/parser_test.go

@@ -368,6 +368,26 @@ func TestJSONExpressionParser(t *testing.T) {
 			labels.FromStrings("param", "1"),
 			NoParserHints(),
 		},
+		{
+			"object element not present",
+			testLine,
+			[]LabelExtractionExpr{
+				NewLabelExtractionExpr("undefined", `pod[""]`),
+			},
+			labels.EmptyLabels(),
+			labels.FromStrings("undefined", ""),
+			NoParserHints(),
+		},
+		{
+			"accessing invalid array index",
+			testLine,
+			[]LabelExtractionExpr{
+				NewLabelExtractionExpr("param", `pod.deployment.params[""]`),
+			},
+			labels.EmptyLabels(),
+			labels.FromStrings("param", ""),
+			NoParserHints(),
+		},
 		{
 			"array string element",
 			testLine,

vendor/github.com/grafana/jsonparser/parser.go

@@ -1037,7 +1037,7 @@ github.com/grafana/go-gelf/v2/gelf
 # github.com/grafana/gomemcache v0.0.0-20240229205252-cd6a66d6fb56
 ## explicit; go 1.18
 github.com/grafana/gomemcache/memcache
-# github.com/grafana/jsonparser v0.0.0-20240425183733-ea80629e1a32
+# github.com/grafana/jsonparser v0.0.0-20241004153430-023329977675
 ## explicit; go 1.13
 github.com/grafana/jsonparser
 # github.com/grafana/loki/pkg/push v0.0.0-20240924133635-758364c7775f => ./pkg/push