Sending a duplicated request to aws s3 bucket with nginx configuration

mirroring_nginx_to_s3_bucket.conf

env AWS_ACCESS_KEY_ID;
env AWS_SECRET_ACCESS_KEY;
env S3_BUCKET_NAME;

events{
  worker_connections 1024;
}

http {	
    server {
	    listen 80;
	    lua_need_request_body on;
	    default_type image/jpeg;
	    
	    location / {
	        proxy_pass http://192.x.x.2;
	        mirror /mirror;
	    	mirror_request_body on;
	    
	    }
	    location /mirror {
			if ($request_method !~ ^(PUT|POST)$ ) {
				return 403;
			}

			if ($content_type != "image/jpg") {
				return 200;
			}

			set_by_lua $bucket "return os.getenv('S3_BUCKET_NAME')";
			set_by_lua $aws_access_key "return os.getenv('AWS_ACCESS_KEY_ID')";
			set_by_lua $aws_secret_key "return os.getenv('AWS_SECRET_ACCESS_KEY')";
			set $aws_backend "http://$bucket.s3.amazonaws.com/";
			set_by_lua_block $request_nuri {
				local body=ngx.req.get_body_data()
				local cache_key = ngx.md5(body)
				local today = ngx.today()
				return "prefix/" .. today .. "/" .. cache_key .. ".jpg"
			}
			set $acl private;
			set $class GLACIER;
			set_by_lua $date "return ngx.cookie_time(ngx.time())";
			set_by_lua_block $auth {
				local canonicalized_amz_headers = "x-amz-acl:" .. ngx.var.acl .. "\nx-amz-date:" .. ngx.var.date .. "\nx-amz-storage-class:" .. ngx.var.class
				local canonicalized_resource = "/" .. ngx.var.bucket .. "/" .. ngx.var.request_nuri
				local http_content_md5 = ""
				if (ngx.var.http_content_md5 ~= nil) then
				  http_content_md5 = ngx.var.http_content_md5
				end
				local http_content_type = ""
				if (ngx.var.http_content_type ~= nil) then
				  http_content_type = ngx.var.http_content_type
				end
				local string_to_sign = "PUT\n" .. http_content_md5 .. "\n" .. http_content_type .. "\n\n" .. canonicalized_amz_headers .. "\n" .. canonicalized_resource
				local aws_signature = ngx.encode_base64(ngx.hmac_sha1(ngx.var.aws_secret_key, string_to_sign))
				return  "AWS " .. ngx.var.aws_access_key .. ":" .. aws_signature
			}
			proxy_set_header Authorization $auth;
			proxy_set_header x-amz-acl $acl;
			proxy_set_header x-amz-storage-class $class;
			proxy_set_header x-amz-date $date;

			proxy_hide_header x-amz-id-2;
			proxy_hide_header x-amz-request-id;

			resolver 8.8.8.8 valid=300s;
			resolver_timeout 10s;

			proxy_method PUT;
			proxy_pass_request_headers on;
			proxy_pass "$aws_backend$request_nuri";
		}
	}
}