ENHANCEMENT: add the additional checksum as a supported put parameter

Signed-off-by: Giuseppe Pellegrino <[email protected]>

docs/output.md

@@ -430,6 +430,18 @@ Specifies the AWS KMS key ID to use for object encryption.
 
 Specifies the 128-bit MD5 digest of the encryption key according to RFC 1321.
 
+## checksum_algorithm
+
+AWS allows to calculate the integrity checksum server side. The additional checksum is
+used to validate the data during upload or download. The following 4 SHA and CRC algorithms are supported:
+
+* CRC32
+* CRC32C
+* SHA1
+* SHA256
+
+For more info refer to [object integrity](https://docs.aws.amazon.com/AmazonS3/latest/userguide/checking-object-integrity.html).
+
 ## compute_checksums
 
 AWS SDK uses MD5 for API request/response by default. On FIPS enabled environment,

lib/fluent/plugin/out_s3.rb

@@ -154,6 +154,8 @@ def initialize
     desc "Arbitrary S3 tag-set for the object"
     config_param :tagging, :string, default: nil
     desc "Arbitrary S3 metadata headers to set for the object"
+    config_param :checksum_algorithm, :string, default: nil
+    desc "Indicates the algorithm you want Amazon S3 to use to create the checksum for the object (CRC32,CRC32C,SHA1,SHA256)"
     config_param :s3_metadata, :hash, default: nil
     config_section :bucket_lifecycle_rule, param_name: :bucket_lifecycle_rules, multi: true do
       desc "A unique ID for this rule"
@@ -368,6 +370,7 @@ def write(chunk)
         put_options[:grant_read] = @grant_read if @grant_read
         put_options[:grant_read_acp] = @grant_read_acp if @grant_read_acp
         put_options[:grant_write_acp] = @grant_write_acp if @grant_write_acp
+        put_options[:checksum_algorithm] = @checksum_algorithm if @checksum_algorithm
         put_options[:tagging] = @tagging if @tagging
 
         if @s3_metadata