Lambda Triggers

Lambda Triggers provide a way to generate events that Lambdas can respond do. Every Lambda Trigger is expected to run a control loop, and is given a dedicated thread in the agent or control plane.

When creating a new Lambda Trigger in the web console, number of templates are offered:

Structure of a Lambda Trigger

A Lambda Trigger contains an initialization function which can be used to perform resource allocations. A context object is made available and can be used for temporary storage.

Then a Lambda Trigger provides a run function, which should emit events that will be delivered to Lambdas.

local redis = require('redis')
local socket = require('socket')
local M = {}

function M.init(context, params)
  local redis_client = redis.connect('my-redis', 6379)
    assert(redis_client:ping())
    context['redis_client'] = redis_client 
end

function M.run(context)
  local redis_client = context.redis_client
  local channels = {'foo', 'bar'}
  for msg, abort in redis_client:pubsub({subscribe=channels}) do 
    local event = {
      timestamp = socket.gettime(),
      msg = msg
    }
    coroutine.yield(event)
  end
end

return M