Wrapping Apache HTTPClient

This talk gives you an insight on how to wrap a Java library nicely for use in JRuby.
Presented on 7 Nov 2013 at the Berlin Ruby User Group.

Source Code: https://github.com/Overbryd/http_client
Gem: http://rubygems.org/gems/http_client

Transcript

2. I need connection pools!
3. http_client
4. http_client server w/ Keep-Alive
5. http_client server w/ Keep-Alive T1
6. http_client server w/ Keep-Alive T1 T2
7. http_client server w/ Keep-Alive T1 T2 T3
8. http_client server w/ Keep-Alive T1 T2 T3 T4
9. http_client server w/ Keep-Alive T1 T2 T3 T4 T5
10. http_client server w/ Keep-Alive T1 T2 T3 T4 T5
11. http_client server w/ Keep-Alive T1 T2 T3 T4 T5
12. resource control ! :max_connections
13. circuit breaker ! timeout when requesting too many resources
15. jruby http client
18. aesterline/jruby-httpclient
19. aesterline/jruby-httpclient $LOAD_PATH.unshift
20. aesterline/jruby-httpclient but the sadest thing is this one issue
21. aesterline/jruby-httpclient
22. aesterline/jruby-httpclient rb2k
23. aesterline/jruby-httpclient no connection pool
24. aesterline/jruby-httpclient :(
26. nahi/httpclient
27. nahi/httpclient all ruby
28. nahi/httpclient correct timeouts
29. nahi/httpclient threadsafe!
30. nahi/httpclient from Japan!
31. nahi/httpclient awesome rock solid http library
32. nahi/httpclient no connection pools
33. nahi/httpclient :(
34. Wrapping Apache HTTPClient from Javaland
36. Java libraries provide everything but the kitchen sink
38. stay focused on what you want to accomplish
39. require "http_client" ! client = HTTPClient.new response = client.get("http://www.google.com/robots.txt") ! response.status # => 200 ! response.body # => # User-agent: * # ...
40. require all necessary jars but import only a subset of all the classes
41. import org.apache.http.impl.client.HttpClients import org.apache.http.impl.conn.BasicHttpClientConnectionManager import org.apache.http.impl.conn.PoolingHttpClientConnectionManager import org.apache.http.client.methods.HttpGet import org.apache.http.client.methods.HttpPost import org.apache.http.client.methods.HttpPut import org.apache.http.client.methods.HttpPatch import org.apache.http.client.methods.HttpDelete import org.apache.http.client.methods.HttpHead import org.apache.http.client.methods.HttpOptions import org.apache.http.client.config.RequestConfig import org.apache.http.entity.StringEntity import org.apache.http.client.entity.UrlEncodedFormEntity import org.apache.http.client.entity.GzipDecompressingEntity import org.apache.http.client.entity.DeflateDecompressingEntity import org.apache.http.message.BasicNameValuePair import org.apache.http.entity.ContentType import org.apache.http.util.EntityUtils import org.apache.http.HttpException import org.apache.http.conn.ConnectTimeoutException import java.io.IOException import java.net.SocketTimeoutException import java.util.concurrent.TimeUnit
43. wrap exceptions from Javaland
46. learn about the thread safety of the classes you use
47. http://hc.apache.org/httpcomponents-client-ga/tutorial/html/fundamentals.html
48. cloc 250 lines
49. managed connection pools, thanks to
50. managed connection pools, thanks to PoolingHttpClientConnectionManager
51. JRuby
52. J
53. def create_connection_manager(options) options[:use_connection_pool] ? create_pooling_connection_manager(options) : BasicHttpClientConnectionManager.new end ! def create_pooling_connection_manager(options) connection_manager = PoolingHttpClientConnectionManager.new connection_manager.max_total = options[:max_connections] max_per_route = options[:max_connections_per_route] || \ options[:max_connections] connection_manager.default_max_per_route = max_per_route end
54. def execute(request) retries = max_retries begin closeable_response = client.execute(request) response_class.new(closeable_response) rescue ConnectTimeoutException, SocketTimeoutException => e retry if (retries -= 1) > 0 raise Timeout, "#{e.message}" rescue IOException => e retry if (retries -= 1) > 0 raise IOError, "#{e.message}" rescue HttpException => e raise Error, "#{e.message}" ensure closeable_response.close if closeable_response end end
55. def read_body(closeable_response) return "" unless entity = closeable_response.entity return "" unless entity.content_length > 0 if content_encoding = entity.content_encoding entity = case content_encoding.value when "gzip", "x-gzip" then GzipDecompressingEntity.new(entity) when "deflate" then DeflateDecompressingEntity.new(entity) else entity end end EntityUtils.to_string(entity, "UTF-8") end end
56. Lukas Rieder ! @Overbryd https://github.com/Overbryd/http_client