How to filter kafka topics based on their names in logstash conf in the output section using if-else condition for elastic search output

[KUMAR_SATYAM]

I am using the new version of Kafka plugin for elkstack

input {
  kafka {
    bootstrap_servers => "1XX.X.X.X:9092"
    topics => ["test_all_logs","test_apiserver_logs","test_orchestrator_logs","test_credentialstore_logs","test_gfac_logs","local_api-orch_logs","__consumer_offsets,local_gfac_logs"]
    auto_offset_reset => "earliest"
    decorate_events => "true"
  }
}

filter{

json {
    source => "message"
    target => "doc"
  }
  mutate { add_field => { "level" => "%{[doc][level]}"}}
  mutate { add_field => { "logger" => "%{[doc][loggerName]}" } }
}

output {
  stdout { codec => rubydebug }
  elasticsearch {
    if {[@metadata][kafka][topic]== "test_all_logs" {
        hosts => ["localhost:9200"]
        index => ["test-all-logs-%{+YYYY.MM.dd}"]
    }
    if [@metadata][kafka][topic]} == "test_apiserver_logs" {
        hosts => ["localhost:9200"]
        index => ["test_apiserver_logs-%{+YYYY.MM.dd}"]
    }
    if [@metadata][kafka][topic]} == "test_orchestrator_logs" {
        hosts => ["localhost:9200"]
        index => ["test_orchestrator_logs-%{+YYYY.MM.dd}"]
    }
    if [@metadata][kafka][topic]} == "test_credentialstore_logs" {
        hosts => ["localhost:9200"]
        index => ["test_credentialstore_logs-%{+YYYY.MM.dd}"]
    }
    if [@metadata][kafka][topic]} == "test_gfac_logs" {
        hosts => ["localhost:9200"]
        index => ["test_gfac_logs-%{+YYYY.MM.dd}"]
    }
  }
}

I am following many links which did not had proper answer:
https://stackoverflow.com/questions/41361756/how-to-write-logstash-filter-to-filter-kafka-topics

https://www.elastic.co/guide/en/logstash/current/plugins-inputs-kafka.html#plugins-inputs-kafka-decorate_events

I got a suggestion that I should add decorate_events => "true". and added @metadata attribute.

I executed the command:

/opt/logstash/bin/logstash -f airavata/logstash-airavata.conf --path.data ./airavata/

But I am getting the below error:

Failed to execute action {:action=>LogStash::PipelineAction::Create/pipeline_id:main, :exception=>"LogStash::ConfigurationError", :message=>"Expected one of #, => at line 24, column 8 (byte 579) after output {\n  stdout { codec => rubydebug }\n\n  elasticsearch {\n    if ", 

:backtrace=>["/opt/logstash/logstash-core/lib/logstash/compiler.rb:42:in `compile_ast'", "/opt/logstash/logstash-core/lib/logstash/compiler.rb:50:in `compile_imperative'", "/opt/logstash/logstash-core/lib/logstash/compiler.rb:54:in `compile_graph'", "/opt/logstash/logstash-core/lib/logstash/compiler.rb:12:in `block in compile_sources'", "org/jruby/RubyArray.java:2486:in `map'", "/opt/logstash/logstash-core/lib/logstash/compiler.rb:11:in `compile_sources'", "/opt/logstash/logstash-core/lib/logstash/pipeline.rb:107:in `compile_lir'", "/opt/logstash/logstash-core/lib/logstash/pipeline.rb:49:in `initialize'", "/opt/logstash/logstash-core/lib/logstash/pipeline.rb:215:in `initialize'", "/opt/logstash/logstash-core/lib/logstash/pipeline_action/create.rb:35:in `execute'", "/opt/logstash/logstash-core/lib/logstash/agent.rb:335:in `block in converge_state'", "/opt/logstash/logstash-core/lib/logstash/agent.rb:141:in `with_pipelines'", "/opt/logstash/logstash-core/lib/logstash/agent.rb:332:in `block in converge_state'", "org/jruby/RubyArray.java:1734:in `each'", "/opt/logstash/logstash-core/lib/logstash/agent.rb:319:in `converge_state'", "/opt/logstash/logstash-core/lib/logstash/agent.rb:166:in `block in converge_state_and_update'", "/opt/logstash/logstash-core/lib/logstash/agent.rb:141:in `with_pipelines'", "/opt/logstash/logstash-core/lib/logstash/agent.rb:164:in `converge_state_and_update'", "/opt/logstash/logstash-core/lib/logstash/agent.rb:90:in `execute'", "/opt/logstash/logstash-core/lib/logstash/runner.rb:362:in `block in execute'", "/opt/logstash/vendor/bundle/jruby/2.3.0/gems/stud-0.0.23/lib/stud/task.rb:24:in `block in initialize'"]}

Can somebody help me with mistake I am doing, with proper syntax, not uncooked syntax?

[magnusbaeck (Magnus Bäck)]

You can't have conditionals inside outputs. Do this instead:

if (...) {
  elasticsearch {
    ...
  }
} else if (...) {
  elasticsearch {
    ...
  }
}
...