To enable http level request/response logs in Application Server (AS), we can use the Access_Log_Valve which is provided in Tomcat 7.
To enable logging, you have to put the following XML xml element under the /Server/Service/Engine/Host/directory element in the {WSO2AS_HOME}/repositoryrepository/conf/tomcat/catalina-server.xmlfile and and restart the AS server.
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<Valve className="org.apache.catalina.valves.AccessLogValve"
directory="${carbon.home}/repository/logs"
prefix="localhost_access_log_sample."
suffix=".log"
pattern="%{xxx}i %{xxx}o"
resolveHosts="false"/> |
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The pattern parameter is used to specify which parts of the request/response needs to be logged. In the above sample, xxx stands for the header name we need to log. Here %{xxx}i stands for the request headers and %{xxx}o stands for the response headers.
Table of Contents
Example 1: Logging request headers
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text/plain; charset=utf-8 */* gzip,deflate,sdch |
Example 2: Logging response headers
The configuration is as follows:
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<Valve className="org.apache.catalina.valves.AccessLogValve"
directory="${carbon.home}/repository/logs"
prefix="localhost_access_log_test."
suffix=".log"
pattern="%{Content-Type}o %{Content-Length}o %{Date}o %{Server}o"
resolveHosts="false"/> |
The above will log Content-type, Content-Length, Date Date and Server headers of every response coming from AS, as follows:
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<Valve className="org.apache.catalina.valves.AccessLogValve"
directory="${carbon.home}/repository/logs"
prefix="localhost_access_log_test."
suffix=".log"
pattern="%r %q %h"
resolveHosts="false"/> |
The above will log the First first line of the request (method and request URI), Query string (prepended with a '?' if it exists) and Remote hostname (or IP) of every request coming to AS as follows. (For more information on all possible values that can be given in the pattern parameter, go to http://tomcat.apache.org/tomcat-7.0-doc/config/valve.html#Access_Log_Valve)
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“GET /example/servlets/servlet/RequestInfoExample?abc=xyz HTTP/1.1” ?abc=xyz 10.100.0.67 |
Example 4: Logging URL encoded parameters
You can not use the Access Log Valve to log URL encoded parameters. However, you can use the Extended Access Log Valve for this. Here only 2 parts ( className and pattern ) are modified from the previous configuration.
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Thereafter, when the POST request is sent together with the URL encoded values param1=value1 and param2=value2:
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POST http://<IP>:<PORT>/example/servlets/servlet/RequestInfoExample |
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