Getting JSON format error in Logstash. Need to decode JSON from the message part - elasticsearch

Question

I am using the below code in my logstash but the message field is coming after getting converted into JSON twice, but I need the message with a single JSON format, how can I decode it from JSON one step back:
file {
id => "my_lt_log"
path => "/logs/logtransformer.log"
type => "log"
start_position => "beginning"
}
}
filter {
if [type] == "log" {
mutate {
remove_field => [ "kubernetes"]
}
mutate {
gsub => [ "message", "(\W)at(\W)", '\1""\2' ]
}
if [message][metadata][proc_id] {
mutate {
add_field => { "[metadata][proc_id]" => "%{[message][metadata][proc_id]}" }
}
}
if "_jsonparsefailure" in [tags] {
mutate {
add_field => {
"logplane" => "adp-app-logs"
"abc" => "%{[message]}"
}
remove_field => [ "message", "kubernetes" ]
}
}
else {
mutate {
rename => {
"path" => "filename"
}
add_field => {
"def" => "%{[message]}"
"message" => "%{[message][message]}"
"timestamp" => "%{[message][timestamp]}"
}
}
}
}
output {
...
}
Output:
{
"_index" : "adp-app-logs-2023.02.03",
"_type" : "_doc",
"_id" : "PpiDF4YBCMtUNdxoMJFW",
"_score" : 0.79323065,
"_source" : {
"#version" : "1",
"service_id" : "%{[message][service_id]}",
"def" : "{\"version\": \"1.1.0\", \"timestamp\": \"2023-02-03T13:41:43.034Z\", \"severity\": \"info\", \"service_id\": \"eric-log-transformer\", \"metadata\" : {\"namespace\": \"zyadros\", \"pod_name\": \"eric-log-transformer-7b64896976-s6h5r\", \"node_name\": \"node-10-63-142-135\", \"pod_uid\": \"336c9706-41a9-41c0-b459-2eb4e9f6e2b4\", \"container_name\": \"logtransformer\"}, \"message\": \"Starting pipeline {:pipeline_id=>'opensearch', 'pipeline.workers'=>2, 'pipeline.batch.size'=>2048, 'pipeline.batch.delay'=>50, 'pipeline.max_inflight'=>4096, 'pipeline.sources'=>['/opt/logstash/resource/searchengine.conf'], :thread=>'#<Thread:0x7649ae47 run>'}\"}",
"#timestamp" : "2023-02-03T13:41:58.044976Z",
"severity" : "%{[message][severity]}"
}
}
Expected Output for the field 'def':
{"version": "1.1.0", "timestamp": "2023-02-06T06:18:33.647Z", "severity": "info", "service_id": "eric-log-transformer", "metadata" : {"namespace": "zyadros", "pod_name": "eric-log-transformer-5cb7dbc6b5-ghrsc", "node_name": "node-10-63-142-135", "pod_uid": "52b8e6fe-9547-4091-9034-36e1141f4391", "container_name": "logtransformer"}, "message": "Starting tcp input listener {:address=>'0.0.0.0:5015', :ssl_enable=>true}"}
Input file sample:
{"version": "1.1.0", "timestamp": "2023-02-06T13:42:59.634Z", "severity": "info", "service_id": "eric-log-transformer", "metadata" : {"namespace": "roshan", "pod_name": "eric-log-transformer-5bc84c4cb-c8qtw", "node_name": "node-10-63-142-135", "pod_uid": "00632d7b-d151-4b0c-84fe-8a6ee6b64b35", "container_name": "logtransformer"}, "message": "Starting pipeline {:pipeline_id=>'logstash', 'pipeline.workers'=>2, 'pipeline.batch.size'=>2048, 'pipeline.batch.delay'=>50, 'pipeline.max_inflight'=>4096, 'pipeline.sources'=>['/opt/logstash/resource/logstash.conf'], :thread=>'#<Thread:0x3d8b1518 run>'}"}
Getting the below Error while adding json {source}:
{
"_index" : "%{logplane}-2023.02.07",
"_type" : "_doc",
"_id" : "9d6xKoYBCoUR1nQuuhlp",
"_score" : 2.969562E-4,
"_source" : {
"path" : "/logs/logtransformer.log",
"#version" : "1",
"tags" : [
"_jsonparsefailure"
],
"#timestamp" : "2023-02-07T07:05:22.465556Z",
"host" : "eric-log-transformer-d6dddd6f9-lp6d7",
"message" : " at [Source: (byte[])' at [Source: (byte[])' at [Source: (byte[])'{'version': '1.1.0', 'timestamp': '2023-02-07T07:05:06.163Z', 'severity': 'warning', 'service_id': 'eric-log-transformer', 'metadata' : {'namespace': 'zyadros', 'pod_name': 'eric-log-transformer-d6dddd6f9-lp6d7', 'node_name': 'node-10-63-142-138', 'pod_uid': '02659e5c-c9ac-49c8-a4bd-74b9477e846d', 'container_name': 'logtransformer'}, 'message': 'Error parsing json {:source=>'message', :raw=>'{\\'version\\': \\'1.1.0\\', \\'timestamp\\': \\'2023-02-07T07:05:02'[truncated 68 bytes]; line: 1, column: 5]>}\"}"
}
},