gistfile1.txt

[hekad]
share_dir = "/usr/share/heka"
pid_file = "/var/run/hekad.pid"
max_message_size = 2097152
maxprocs = 2

[DashboardOutput]
ticker_interval = 5

[ApiInput]
type = "UdpInput"
address = "127.0.0.1:5566"

[ApiEncoder]
type = "SandboxEncoder"
filename = "lua_encoders/es_payload.lua"

    [ApiEncoder.config]
    index = "copy_log_%{%Y.%m.%d}"
    type_name = "api-dispatch"
    es_index_from_timestamp = true

[ApiOuput]
type="ElasticSearchOutput"
server = "http://-:9200"
message_matcher = "Logger == 'ApiInput'"
encoder = "ApiEncoder"
use_buffering = false
flush_interval = 5000
flush_count = 1000

[LogOutput]
message_matcher = "Logger == 'ApiInput'"
encoder = "ApiEncoder"

Stacktrace:

https://gist.github.com/rstruber/4ebb400806577ece510a