# Parsing json inside json

**URL:** <https://discuss.elastic.co/t/parsing-json-inside-json/328496>\
**Category:** Logstash\
**Created:** [March 24, 2023, 8:41pm UTC](https://discuss.elastic.co/t/parsing-json-inside-json/328496 "2023-03-24T20:41:51Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![eirik](https://avatars.discourse-cdn.com/v4/letter/e/b19c9b/32.png) [@eirik](https://discuss.elastic.co/u/eirik)\
**Post date:** [March 24, 2023, 8:41pm UTC](https://discuss.elastic.co/t/parsing-json-inside-json/328496/1 "2023-03-24T20:41:51Z")

</div>

I'm new to logstash and wanted to test using it reading loglines from IBM Cloud and struggling with parsing this log record using logstash. The log line is a json object, and inside this one of the fields starts with plain text and then contains a new json object.

I only want to keep log lines where the msg field inside the json document in the message field contains the text "Slow query"

I want to keep fields \_ip and \_ipremote from the outer json document and then parse the message field by removing the plain text and return the jsonobject together with the 2 values from the \_ip and \_ipremote values. all these values should be inserted into elastic.

Anyone out there that can give me any pointers 🙂

```auto
{
    "_host": "ibm-cloud-databases-prod",
    "_label": {
        "database": "mongodb",
        "member": "m-0",
        "crn": "crn:v1:bluemix:public:databases-for-mongodb",
        "region": "eu-de"
    },
    "_logtype": "json",
    "_file": "crn:v1:bluemix:public:databases-for-mongodb",
    "_ts": 1678669328787,
    "_platform": "ibm-cloud-databases-prod",
    "_app": "crn:v1:bluemix:public:databases-for-mongodb",
    "_ip": "172.33.226.32",
    "_id": "1588254284607938573",
    "_ipremote": "126.19.43.43",
    "message": "2023-03-13T01:02:07.926431297Z stdout F {\"t\":{\"$date\":\"2023-03-13T01:02:07.926+00:00\"},\"s\":\"I\", \"c\":\"COMMAND\", \"id\":51803, \"ctx\":\"conn49\",\"msg\":\"Slow query\",\"attr\":{\"type\":\"command\",\"ns\":\"local.oplog.rs\",\"command\":{\"find\":\"oplog.rs\",\"filter\":{\"ts\":{\"gte\":{\"$timestamp\":{\"t\":1678665727,\"i\":0}}}},\"lsid\":{\"id\":{\"$uuid\":\"34gdg-12c5-4344335-b49a-sdfe34ce4757\"}},\"$clusterTime\":{\"clusterTime\":{\"$timestamp\":{\"t\":1678669321,\"i\":1}},\"signature\":{\"hash\":{\"$binary\":{\"base64\":\"AAAAAAAAAAAAAAAAAAAAAAAAAAA=\",\"subType\":\"0\"}},\"keyId\":0}},\"$db\":\"local\",\"$readPreference\":{\"mode\":\"primaryPreferred\"}},\"planSummary\":\"COLLSCAN\",\"keysExamined\":0,\"docsExamined\":1152813,\"cursorExhausted\":true,\"numYields\":1152,\"nreturned\":0,\"queryHash\":\"D06EDDC0\",\"planCacheKey\":\"D06EDDC0\",\"reslen\":228,\"locks\":{\"ReplicationStateTransition\":{\"acquireCount\":{\"w\":1153}},\"Global\":{\"acquireCount\":{\"r\":1153}},\"Database\":{\"acquireCount\":{\"r\":1153}},\"Mutex\":{\"acquireCount\":{\"r\":1}},\"oplog\":{\"acquireCount\":{\"r\":1153}}},\"storage\":{\"data\":{\"bytesRead\":209816454,\"timeReadingMicros\":87782}},\"protocol\":\"op_msg\",\"durationMillis\":845}}",
    "saveServiceCopy": true,
    "logSourceCRN": "crn:v1:bluemix:public:databases-for-mongodb",
    "_mezmo_line_size": 344
}

```

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<div class="post-metadata">

**Author:** ![Badger](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/badger/32/25190_2.png) [@Badger](https://discuss.elastic.co/u/Badger)\
**Post date:** [March 24, 2023, 9:58pm UTC](https://discuss.elastic.co/t/parsing-json-inside-json/328496/2 "2023-03-24T21:58:57Z")

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You could try

```
    json { source => "message" }
    prune { whitelist_names => ["message", "_ip", "_ipremote"] }
    dissect { mapping => { "message" => "%{[@metadata][ts]} %{} %{} %{[@metadata][restOfline]}" } }
    date { match => ["[@metadata][ts]", "ISO8601" ] }
    json { source => "[@metadata][restOfline]" remove_field => ["message"] }
    if [msg] !~ /Slow query/ { drop {} }

```

That assumes that the [message] field in the event starts off containing the entire pretty-printed JSON object.

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<div class="post-metadata">

**Author:** ![eirik](https://avatars.discourse-cdn.com/v4/letter/e/b19c9b/32.png) [@eirik](https://discuss.elastic.co/u/eirik)\
**Post date:** [March 29, 2023, 1:42pm UTC](https://discuss.elastic.co/t/parsing-json-inside-json/328496/3 "2023-03-29T13:42:14Z")

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Thanks very much for your help 🙂

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [April 26, 2023, 1:43pm UTC](https://discuss.elastic.co/t/parsing-json-inside-json/328496/4 "2023-04-26T13:43:02Z")

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