Aws kinesis credentials should pass aws_credentials to KinesisService (#5)

* AWS' SDK concerns for cached credentials should not be handled by the logger as they're handled by the aws sdk

* [Doc] - added a guide for configuring AwsKinesisLogger backend.

* [Doc] - Updated README based on reviews

* AwsKinesisLogger should pass aws_credentials config option to the Kinesis Service

Author: ddragosd

src/lua/api-gateway/logger/backend/AwsKinesisLogger.lua

@@ -48,24 +48,16 @@ function _M:constructor(o)
     self.aws_access_key = o.aws_access_key
     self.aws_iam_user = o.aws_iam_user
 
-    local iam_user = o.aws_iam_user
-
     local kinesisServiceConfig = {
         aws_region = o.aws_region,
-        aws_secret_key = o.aws_secret_key,
-        aws_access_key = o.aws_access_key,
-        aws_debug = true, -- print warn level messages on the nginx logs
-        aws_conn_keepalive = 60000, -- how long to keep the sockets used for AWS alive
-        aws_conn_pool = 100 -- the connection pool size for sockets used to connect to AWS
+        aws_credentials = o.aws_credentials, -- credentials provider
+        aws_secret_key = o.aws_secret_key, -- deprecated but kept for backwards compatibility
+        aws_access_key = o.aws_access_key, -- deprecated but kept for backwards compatibility
+        aws_debug = o.aws_debug, -- print warn level messages on the nginx logs
+        aws_conn_keepalive = o.aws_conn_keepalive, -- how long to keep the sockets used for AWS alive
+        aws_conn_pool = o.aws_conn_pool -- the connection pool size for sockets used to connect to AWS
     }
 
-    if (iam_user ~= nil) then
-        kinesisServiceConfig.aws_iam_user = iam_user.iam_user
-        kinesisServiceConfig.security_credentials_host = iam_user.security_credentials_host
-        kinesisServiceConfig.security_credentials_port = iam_user.security_credentials_port
-        kinesisServiceConfig.shared_cache_dict = iam_user.shared_cache_dict
-    end
-
     kinesisService = KinesisService:new(kinesisServiceConfig)
 end
 

test/perl/aws_kinesis_logger.t

@@ -100,7 +100,8 @@ __DATA__
                     backend_opts = {
                         aws_region = ngx.var.aws_region,
                         kinesis_stream_name = ngx.var.kinesis_stream_name,
-                        aws_iam_user = {
+                        aws_credentials = {
+                            provider = "api-gateway.aws.AWSIAMCredentials",
                             security_credentials_host = "127.0.0.1",      -- test only
                             security_credentials_port = $TEST_NGINX_PORT, -- test only
                             security_credentials_timeout = 60 * 60 * 24,