Redis input plugin not taking parameter format="json_event"?

Hi all,
I am facing some issues while installing new KEL on my redhat linux 7.
java 8 ,elastic serach-2.3.5 , logstash-Version : 2.3.4,kibana -4.5.4 and redis-2.8.19.

  1. logstash keep crashing
    for this i have verified my logsatsh config file and ran sudo service logstash configtest ,got Configuration fails.
  2. after that I have made a chnage to config file

modifying the format="json_event" to codec => {line => {format => "json_event"}}
configuration test OK.
But the logstash service still crashing

my config file :
input {
tcp { port => 28777 codec=>"plain" type=>"sample" }
tcp { port => 28778 codec=>"json" type=>"sample2" }
redis {
host => ""
type => "redis-input"
# these settings should match the output of the agent
data_type => "list"
key => "logstash"
# We use json_event here since the sender is a logstash agent
codec => { line => {format => "json_event"}}
} }
output {
elasticsearch {
embedded => false
# bind_host => "localhost"
hosts => ["localhost:9200"]
cluster => "elasticsearch-DEV"
node_name => "logstash"}

exception=>#<NoMethodError: undefined method decode' for ["line", {"format"=>"json_event"}]:Array>, :backtrace=>["/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-input-redis-2.0.6/lib/logstash/inputs/redis.rb:182:inqueue_event'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-input-redis-2.0.6/lib/logstash/inputs/redis.rb:220:in list_batch_listener'", "org/jruby/'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-input-redis-2.0.6/lib/logstash/inputs/redis.rb:219:in list_batch_listener'", "org/jruby/'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-input-redis-2.0.6/lib/logstash/inputs/redis.rb:204:in list_runner'", "org/jruby/'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-input-redis-2.0.6/lib/logstash/inputs/redis.rb:123:in run'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.4-java/lib/logstash/pipeline.rb:342:ininputworker'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.4-java/lib/logstash/pipeline.rb:336:in `start_input'"], :level=>:error, :file=>"logstash/inputs/redis.rb", :line=>"187", :method=>"queue_event"}
{:timestamp=>"2016-08-17T11:36:22.399000-0600", :message=>"stopping", :plugin=><LogStash::Inputs::Tcp port=>28778, codec=><LogStash::Codecs::JSON charset=>"UTF-8">, type=>"sample2", host=>"", data_timeout=>-1, mode=>"server", ssl_enable=>false, ssl_verify=>true, ssl_key_passphrase=>>, :level=>:debug, :file=>"logstash/inputs/base.rb", :line=>"81", :method=>"do_stop"}

Please suggest me here and let me know if I am missing anything .

Use codec => json for the redis input too.