Start on S3 site

1 files changed, 69 insertions, 0 deletions

diff --git a/lib/active_file/sites/s3_site.rb b/lib/active_file/sites/s3_site.rb
new file mode 100644
index 0000000000..46c409405a
--- /dev/null
+++ b/lib/active_file/sites/s3_site.rb
@@ -0,0 +1,69 @@
+require "aws-sdk"
+
+class ActiveFile::Sites::S3Site < ActiveFile::Site
+  attr_reader :client, :bucket
+
+  def initialize(access_key_id:, secret_access_key:, region:, bucket:)
+    @client = Aws::S3::Resource.new(access_key_id: access_key_id, secret_access_key: secret_access_key, region: region)
+    @bucket = @client.bucket(bucket)
+  end
+
+  def upload(key, data)
+    object_for(key).put(body: data)
+  end
+
+  def download(key)
+    if block_given?
+      stream(key, &block)
+    else
+      object_for(key).read
+    end
+  end
+
+  def delete(key)
+    object_for(key).delete
+  end
+
+  def exists?(key)
+    object_for(key).exists?
+  end
+
+
+  def byte_size(key)
+    object_for(key).head[:size]
+  end
+
+  def checksum(key)
+    head = object_for(key).head
+
+    # If the etag has no dashes, it's the MD5
+    if !head.etag.include?("-")
+      head.etag.gsub('"', '')
+    # Check for md5 in metadata if it was uploaded via multipart
+    elsif md5sum = head.meta["md5sum"]
+      md5sum
+    # Otherwise, we don't have a digest yet for this key
+    else
+      nil
+    end
+  end
+
+
+  private
+    def object_for(key)
+      bucket.object(key)
+    end
+
+    # Reads the object for the given key in chunks, yielding each to the block.
+    def stream(key, options = {}, &block)
+      object = object_for(key)
+
+      chunk_size = 5242880 # 5 megabytes
+      offset = 0
+
+      while offset < object.content_length
+        yield object.read(options.merge(:range => "bytes=#{offset}-#{offset + chunk_size - 1}"))
+        offset += chunk_size
+      end
+    end
+end