AWS Lua Module

1. Overview

Lua wrapper for the aws-cpp-sdk library.

2. Module

2.1. Example Usage

require "aws.kinesis"

local reader = aws.kinesis.simple_consumer(streamName)
while true do
    local records, cp = reader:receive()
    for i, data in ipairs(records) do
      -- process data
    end
end

2.2. Functions

2.2.1. simple_consumer

Creates a simple Kinesis consumer. This client will consume all shards and properly handle splits/merges. However, since it is not distributed it is limited to streams with up to ~50 shards on a 1Gb network interface.

local reader = aws.kinesis.simple_consumer(streamName, iteratorType, checkpoints, clientConfig, credentialProvider, roleArn)

Arguments

• streamName (string) Kinesis stream name
• iteratorType (string/number/nil)
  • "TRIM_HORIZON" (default)
  • "LATEST"
  • number (time_t timestamp) converts to AT_TIMESTAMP iterator
• checkpoints (string/nil) Value returned by receive()
• clientConfig (table/nil) https://sdk.amazonaws.com/cpp/api/LATEST/struct_aws_1_1_client_1_1_client_configuration.html
• credentialProvider (enum/nil)
  • INSTANCE (default)
  • CHAIN
  • ROLE
• roleArn (nil/string) Only used when credentialProvider == ROLE

Return

• reader (userdata) or an error is thrown

2.2.2. simple_producer

Creates a simple Kinesis producer.

local writer = aws.kinesis.simple_producer(clientConfig, credentialProvider, roleArn)

Arguments

• clientConfig (table/nil) https://sdk.amazonaws.com/cpp/api/LATEST/struct_aws_1_1_client_1_1_client_configuration.html
• credentialProvider (enum/nil)
  • INSTANCE (default)
  • CHAIN
  • ROLE
• roleArn (nil/string) Only used when credentialProvider == ROLE

Return

• writer (userdata) or an error is thrown

2.3. simple_consumer Methods

2.3.1. receive

Reads a set of records from the Kinesis stream.

local records, checkpoints = reader:receive()

Arguments

• none

Returns

• records (array) Zero or more data records (throws on error)
• checkpoints (string/nil) TSV of shardId, sequenceId items (one per line)

2.4. simple_producer Methods

2.4.1. send

Writes a record to the Kinesis stream.

local rv, err = writer:send(streamName, data, key)

Arguments

• streamName (string) Kinesis stream name
• data (string) Data to send
• key (string) Key for shard partitioning

Return

• rv (integer) Return value
  • 0 - success
  • -1 - error
  • -3 - retry
• err (string/nil) nil on success

2.4.2. open_shard_count

Returns the open number of shards in the stream.

local cnt = writer:open_shard_count(streamName)

Arguments

• streamName (string) Kinesis stream name

Return

• cnt (integer/nil) Number of open shards (nil when the request can/should be retried, throws on fatal error)
• err (string/nil) nil on success