[NET-552] SocketTimeoutException connecting a FTP server via an HTTP Proxy

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.3
• Fix Version/s: 3.4
• Component/s: FTP
• Labels: FTP HTTP Proxy SocketTimeout

Environment

All

• Assignee: Unassigned
• Reporter: Quentin Devriendt
• Created: 12/Aug/14 09:56
• Updated: 26/Nov/15 16:34
• Resolved: 08/Jan/15 23:44

Description

Randomly, we're experiencing SocketTimoutException when we connect an FTP via an Http Proxy :

java.io.IOException: Timed out waiting for initial connect reply
	at org.apache.commons.net.ftp.FTP._connectAction_(FTP.java:403)
	at org.apache.commons.net.ftp.FTPClient._connectAction_(FTPClient.java:931)
	at org.apache.commons.net.ftp.FTPClient._connectAction_(FTPClient.java:925)
	at org.apache.commons.net.ftp.FTPHTTPClient.connect(FTPHTTPClient.java:144)
Caused by: java.net.SocketTimeoutException: Read timed out
	at java.net.SocketInputStream.socketRead0(Native Method)
	at java.net.SocketInputStream.read(SocketInputStream.java:150)
	at java.net.SocketInputStream.read(SocketInputStream.java:121)
	at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:284)
	at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:326)
	at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:178)
	at java.io.InputStreamReader.read(InputStreamReader.java:184)
	at java.io.BufferedReader.fill(BufferedReader.java:161)
	at java.io.BufferedReader.read(BufferedReader.java:182)
	at org.apache.commons.net.io.CRLFLineReader.readLine(CRLFLineReader.java:58)
	at org.apache.commons.net.ftp.FTP.__getReply(FTP.java:315)
	at org.apache.commons.net.ftp.FTP.__getReply(FTP.java:295)
	at org.apache.commons.net.ftp.FTP._connectAction_(FTP.java:397)
	... 6 more

After analysis, I think the problem is that commons-net opens 2 BufferedReader on the same InputStream : first in the FTPHTTPClient.tunnelHandshake method, and the second in FTP._connectAction() method.
If the first BufferedReader reads all datas in the socket, the second waits until SocketTimeout.