Debugging tip: Get wire trace information from a client

You can get wire trace information from an AWS client by setting the http_wire_trace Boolean. Wire trace information helps differentiate client changes, service issues, and user errors. When true, the setting shows what is being sent on the wire. The following example creates an Amazon S3 client with wire tracing enabled at the time of client creation.

s3 = Aws::S3::Client.new(http_wire_trace: true)

Given the following code and the argument bucket_name, the output displays a message that says whether a bucket with that name exists.

require 'aws-sdk-s3'

s3 = Aws::S3::Resource.new(client: Aws::S3::Client.new(http_wire_trace: true))

if s3.bucket(ARGV[0]).exists?
  puts "Bucket #{ARGV[0]} exists"
else
  puts "Bucket #{ARGV[0]} does not exist"
end

If the bucket exists, the output is similar to the following. (Returns were added to the HEAD line for readability.)

opening connection to bucket_name.s3-us-west-1.amazonaws.com:443...
opened
starting SSL for bucket_name.s3-us-west-1.amazonaws.com:443...
SSL established, protocol: TLSv1.2, cipher: ECDHE-RSA-AES128-GCM-SHA256
-> "HEAD / HTTP/1.1
    Accept-Encoding: 
    User-Agent: aws-sdk-ruby3/3.171.0 ruby/3.2.2 x86_64-linux aws-sdk-s3/1.120.0
    Host: bucket_name.s3-us-west-1.amazonaws.com
    X-Amz-Date: 20230427T143146Z
/* omitted */
Accept: */*\r\n\r\n"
-> "HTTP/1.1 200 OK\r\n"
-> "x-amz-id-2: XxB2J+kpHgTjmMUwpkUI1EjaFSPxAjWRgkn/+z7YwWc/iAX5E3OXRBzJ37cfc8T4D7ELC1KFELM=\r\n"
-> "x-amz-request-id: 5MD4APQQS815QVBR\r\n"
-> "Date: Thu, 27 Apr 2023 14:31:47 GMT\r\n"
-> "x-amz-bucket-region: us-east-1\r\n"
-> "x-amz-access-point-alias: false\r\n"
-> "Content-Type: application/xml\r\n"
-> "Server: AmazonS3\r\n"
-> "\r\n"
Conn keep-alive
Bucket bucket_name exists

You can also turn on wire tracing after client creation.

s3 = Aws::S3::Client.new
s3.config.http_wire_trace = true

For more information on the fields in the wire trace information reported, see Transfer Family required request headers.