How to turn off Netty library debug output?
Solution 1
judging by the abbreviated package names seems to me slf4j/logback is being used for logging here. in that case just try including a logback.xml configuration file in your classpath. something along the lines of
<?xml version="1.0" encoding="UTF-8" ?>
<configuration>
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
</encoder>
</appender>
<root level="INFO">
<appender-ref ref="STDOUT"/>
</root>
<logger name="com.ning.http.client" level="WARN"/>
</configuration>
the above xml would cause anything under com.ning.http.client (and downwards) to omit only warnings and worse to the output, which will be streamed to system.out. anything else will ommit INFO+ you can find more information on configuring logback here: http://logback.qos.ch/manual/configuration.html
Solution 2
Late posting for an old question I know but I recently had to turn off annoying repetitive INFO level logging coming from netty:
[main] INFO com.ning.http.client.providers.netty.NettyAsyncHttpProvider - Number of application's worked threads is 16
In my case I needed to disable it programmatically. Looking into slf4j org.slf4j.impl.SimpleLogger (the logger facade called by netty) I discovered an easy way to control the default slf4j log level for all SimpleLogger instances in your own startup code:
System.setProperty(SimpleLogger.DEFAULT_LOG_LEVEL_KEY, "warn");
or for just the logger instance I was interested in:
System.setProperty(SimpleLogger.LOG_KEY_PREFIX + "com.ning.http.client", "warn");
The value can be any of "trace", "debug", "info", "warn", or "error" with the default being "info".
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Jonathan Stray
Journalist, computer scientist, internationalist. Building the @overviewproject open-source document mining system for the Associated Press. Circus geek.
Updated on July 09, 2022Comments
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Jonathan Stray 3 days
I am using Netty (via the Ning async HTTP library) to retrieve documents via HTTP. This produces a huge amount of debug output the console, as listed below for a single document request.
Anyone know how to turn this off? I really don't need to see this output.
I'm calling from Scala, if that makes any difference.
15:07:14.273 [run-main] DEBUG c.n.h.c.p.n.NettyAsyncHttpProvider - Non cached request DefaultHttpRequest(chunked: false) GET /api/search.json?q=foo HTTP/1.1 Host: www.documentcloud.org Connection: keep-alive Accept: */* User-Agent: NING/1.0 using Channel [id: 0x2839ca40] 15:07:14.930 [New I/O client worker #1-1] DEBUG c.n.h.c.p.n.NettyAsyncHttpProvider - Request DefaultHttpRequest(chunked: false) GET /api/search.json?q=foo HTTP/1.1 Host: www.documentcloud.org Connection: keep-alive Accept: */* User-Agent: NING/1.0 Response DefaultHttpResponse(chunked: true) HTTP/1.1 200 OK Content-Type: application/json; charset=utf-8 Content-Length: 10477 Connection: keep-alive Vary: Accept-Encoding Status: 200 X-Powered-By: Phusion Passenger (mod_rails/mod_rack) 3.0.13 ETag: "4f8f766d639dd84d014dfee3abb45de2" X-Runtime: 611 Cache-Control: private, max-age=0, must-revalidate Server: nginx/1.2.1 + Phusion Passenger 3.0.13 (mod_rails/mod_rack) 15:07:14.941 [New I/O client worker #1-1] DEBUG c.n.h.c.p.netty.NettyConnectionsPool - Adding uri: http://www.documentcloud.org:80 for channel [id: 0x2839ca40, /10.5.165.61:56133 => www.documentcloud.org/75.101.159.206:80] 15:07:16.921 [New I/O client worker #1-1] DEBUG c.n.h.c.p.n.NettyAsyncHttpProvider - Channel Closed: [id: 0x2839ca40, /10.5.165.61:56133 :> www.documentcloud.org/75.101.159.206:80] with attachment com.ning.[email protected]63182c3d 15:08:13.924 [Timer-0] DEBUG c.n.h.c.p.netty.NettyConnectionsPool - Entry count for : http://www.documentcloud.org:80 : 0
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crockpotveggies over 8 yearsthis also works on Scala projects if you're using the Scala-Dispatch library. Place it in the same location
src/main/resources
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ch271828n about 2 yearsAwesome! Works for me