GCP Pub/Sub Subscriber Input

1. Sample Configuration

filename            = "gcp_pubsub.lua"
ticker_interval     = 1
instruction_limit   = 0

channel             = "pubsub.googleapis.com"
project             = "mozilla-data-poc-198117"
topic               = "pubsub_grpc"
subscription_name   = "test"
batch_size          = 1000 -- default/maximum
max_async_requests  = 20 -- default (0 synchronous only)

-- Heka message table containing the default header values to use, if they are
-- not populated by the decoder. If 'Fields' is specified it should be in the
-- hashed based format see:  http://mozilla-services.github.io/lua_sandbox/heka/message.html
-- This input will always default the Type header to the specified streamName.
-- default_headers = nil

-- printf_messages = -- see: https://mozilla-services.github.io/lua_sandbox_extensions/lpeg/modules/lpeg/printf.html

-- Specifies a module that will decode the raw data and inject the resulting message.
-- Supports the same syntax as an individual sub decoder
-- see: https://mozilla-services.github.io/lua_sandbox_extensions/lpeg/io_modules/lpeg/sub_decoder_util.html
-- Default:
-- decoder_module = "decoders.payload"

source code: gcp_pubsub.lua