add option for additional settings

docs/index.asciidoc

@@ -77,6 +77,7 @@ 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}-bucket>> |<<string,string>>|Yes
 | <<plugins-{type}s-{plugin}-canned_acl>> |<<string,string>>, one of `["private", "public-read", "public-read-write", "authenticated-read", "aws-exec-read", "bucket-owner-read", "bucket-owner-full-control", "log-delivery-write"]`|No
@@ -120,6 +121,29 @@ This plugin uses the AWS SDK and supports several ways to get credentials, which
 4. Environment variables `AMAZON_ACCESS_KEY_ID` and `AMAZON_SECRET_ACCESS_KEY`
 5. IAM Instance Profile (available when running inside EC2)
 
+[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]
+    output {
+      s3 {
+        access_key_id => "1234",
+        secret_access_key => "secret",
+        region => "eu-west-1",
+        bucket => "logstash-test",
+        additional_settings => {
+          "force_path_style => true,
+          "follow_redirects" => false
+        }
+      }
+    }
+
 [id="plugins-{type}s-{plugin}-aws_credentials_file"]
 ===== `aws_credentials_file` 
 

lib/logstash/outputs/s3.rb

@@ -106,6 +106,8 @@ class LogStash::Outputs::S3 < LogStash::Outputs::Base
   # S3 bucket
   config :bucket, :validate => :string, :required => true
 
+  config :additional_settings, :validate => :hash, :default => {}
+
   # Set the size of file in bytes, this means that files on bucket when have dimension > file_size, they are stored in two or more file.
   # If you have tags then it will generate a specific size file for every tags
   ##NOTE: define size of file is the better thing, because generate a local temporary file on disk and then put it in bucket.
@@ -267,9 +269,9 @@ def close
   end
 
   def full_options
-    options = Hash.new
+    options = aws_options_hash || {}
     options[:signature_version] = @signature_version if @signature_version
-    options.merge(aws_options_hash)
+    @additional_settings.merge(options)
   end
 
   def normalize_key(prefix_key)

spec/outputs/s3_spec.rb

@@ -24,8 +24,7 @@
   subject { described_class.new(options) }
 
   before do
-    allow(subject).to receive(:bucket_resource).and_return(mock_bucket)
-    allow_any_instance_of(LogStash::Outputs::S3::WriteBucketPermissionValidator).to receive(:valid?).with(mock_bucket, subject.upload_options).and_return(true)
+    allow_any_instance_of(LogStash::Outputs::S3::WriteBucketPermissionValidator).to receive(:valid?).and_return(true)
   end
 
   context "#register configuration validation" do
@@ -143,6 +142,29 @@
       expect { s3.register }.to raise_error(LogStash::ConfigurationError)
     end
 
+    describe "additional_settings" do
+      context "when enabling force_path_style" do
+        let(:additional_settings) do
+          { "additional_settings" => { "force_path_style" => true } }
+        end
+
+        it "validates the prefix" do
+          expect(Aws::S3::Bucket).to receive(:new).twice.with(anything, hash_including("force_path_style" => true)).and_call_original
+          described_class.new(options.merge(additional_settings)).register
+        end
+      end
+      context "when using a non existing setting" do
+        let(:additional_settings) do
+          { "additional_settings" => { "doesnt_exist" => true } }
+        end
+
+        it "raises an error" do
+          plugin = described_class.new(options.merge(additional_settings))
+          expect { plugin.register }.to raise_error(ArgumentError)
+        end
+      end
+    end
+
     it "allow to not validate credentials" do
       s3 = described_class.new(options.merge({"validate_credentials_on_root_bucket" => false}))
       expect_any_instance_of(LogStash::Outputs::S3::WriteBucketPermissionValidator).not_to receive(:valid?).with(any_args)
@@ -152,6 +174,7 @@
 
   context "receiving events" do
     before do
+      allow(subject).to receive(:bucket_resource).and_return(mock_bucket)
       subject.register
     end