add support for additional_settings option (#141)

Author: jsvd

docs/index.asciidoc

@@ -34,6 +34,7 @@ This plugin supports the following configuration options plus the <<plugins-{typ
 |=======================================================================
 |Setting |Input type|Required
 | <<plugins-{type}s-{plugin}-access_key_id>> |<<string,string>>|No
+| <<plugins-{type}s-{plugin}-additional_settings>> |<<hash,hash>>|No
 | <<plugins-{type}s-{plugin}-aws_credentials_file>> |<<string,string>>|No
 | <<plugins-{type}s-{plugin}-backup_add_prefix>> |<<string,string>>|No
 | <<plugins-{type}s-{plugin}-backup_to_bucket>> |<<string,string>>|No
@@ -139,6 +140,28 @@ Whether to delete processed files from the original bucket.
 
 Ruby style regexp of keys to exclude from the bucket
 
+[id="plugins-{type}s-{plugin}-additional_settings"]
+===== `additional_settings`
+
+  * Value type is <<hash,hash>>
+  * Default value is `{}`
+
+Key-value pairs of settings and corresponding values used to parametrize
+the connection to s3. See full list in https://docs.aws.amazon.com/sdkforruby/api/Aws/S3/Client.html[the AWS SDK documentation]. Example:
+
+[source,ruby]
+    input {
+      s3 {
+        "access_key_id" => "1234",
+        "secret_access_key" => "secret",
+        "bucket" => "logstash-test",
+        "additional_settings" => {
+          "force_path_style => true,
+          "follow_redirects" => false
+        }
+      }
+    }
+
 [id="plugins-{type}s-{plugin}-interval"]
 ===== `interval` 
 

lib/logstash/inputs/s3.rb

@@ -35,6 +35,8 @@ class LogStash::Inputs::S3 < LogStash::Inputs::Base
   # If specified, the prefix of filenames in the bucket must match (not a regexp)
   config :prefix, :validate => :string, :default => nil
 
+  config :additional_settings, :validate => :hash, :default => {}
+
   # The path to use for writing state. The state stored by this plugin is
   # a memory of files already processed by this plugin.
   #
@@ -386,7 +388,8 @@ def delete_file_from_bucket(object)
 
   private
   def get_s3object
-    s3 = Aws::S3::Resource.new(aws_options_hash)
+    options = @additional_settings.merge(aws_options_hash || {})
+    s3 = Aws::S3::Resource.new(options)
   end
 
   private

spec/inputs/s3_spec.rb

@@ -76,6 +76,39 @@
         subject.send(:get_s3object)
       end
     end
+
+    describe "additional_settings" do
+      context 'when force_path_style is set' do
+        let(:settings) {
+          {
+            "additional_settings" => { "force_path_style" => true },
+            "bucket" => "logstash-test",
+          }
+        }
+
+        it 'should instantiate AWS::S3 clients with force_path_style set' do
+          expect(Aws::S3::Resource).to receive(:new).with({
+            :region => subject.region,
+            "force_path_style" => true
+          }).and_call_original
+
+          subject.send(:get_s3object)
+        end
+      end
+
+      context 'when an unknown setting is given' do
+        let(:settings) {
+          {
+            "additional_settings" => { "this_setting_doesnt_exist" => true },
+            "bucket" => "logstash-test",
+          }
+        }
+
+        it 'should raise an error' do
+          expect { subject.send(:get_s3object) }.to raise_error(ArgumentError)
+        end
+      end
+    end
   end
 
   describe "#list_new_files" do