curl -H "Host: <hostname>" http://<ip>:9080/path-to-api
The hostname should be the remote domain name and the IP should be the node specific IP.
A good reference is https://drewish.com/2010/03/29/using-curl-and-the-host-header-to-bypass-a-load-balancer/
Quick Method to see Kafka-Broker uptime
lstart and etime are the actual start time and the actual elapsed time since start
[userid@kafka-server ~]$ ps -eo pid,comm,lstart,etime,time,args | grep -i kafka | grep -v grep 9863 java Thu Nov 3 16:19:38 2017 05:25:55 00:09:55 /usr/jdk64/java-1.8.0-openjdk- 1.8.0.77-0.b03.el7_2.x86_64/ bin/java -Xmx1G -Xms1G -server -XX:+UseG1GC -XX:MaxGCPauseMillis=20 -XX: InitiatingHeapOccupancyPercent =35 -XX:+DisableExplicitGC -Djava.awt.headless=true -Xloggc:/var/log/kafka/ kafkaServer-gc.log -verbose:gc -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintGCTimeStamps -Dkafka.logs.dir=/var/log/ kafka -Dlog4j.configuration=file:/ usr/iop/current/kafka-broker/ bin/../config/log4j.properties -cp :/kafka-broker/bin/../libs/* -Xmx8g -Xms8g -Djava.security.auth.login. config=/kafka-broker/config/ kafka_jaas.conf kafka Kafka /kafka-broker/config/server. properties
I know you all have heard the saying “Teach a Man to Fish, and you feed him for a lifetime. Give a main a Fish, and you feed him for one Meal”. This post is hopefully going to help you eat for many meals.
The topic of this post is to uncover how we make the REST requests in the IBM Social Business Toolkit SDK, and show you how to do some advanced debugging in the IBM Social Business Toolkit SDK. I am going to do so using only one addition to the running Java Code, and based on the Apache Http Client Logging.
You can create your project, for instance copying the code from my simple example of using the Social Business toolkit. I just happen to be coding in Eclipse, and I run that code. I get the results:
+F: my forum +F: Lotus Greenhouse +F: test +F: Connections 5.0 with CR1 and Portal 8.0.0.1 with CF14 +F: StandAloneForum1
That’s what the code is getting back from the Server, but I want to know what’s actually being requested.
Click Run > Run Configurations
Click on Example App
Click on Arguments
Copy and Paste the following Arguments
-Dorg.apache.commons.logging.Log=org.apache.commons.logging.impl.SimpleLog -Dorg.apache.commons.logging.simplelog.showdatetime=true -Dorg.apache.commons.logging.simplelog.log.org.apache.http=DEBUG -Dorg.apache.commons.logging.simplelog.log.org.apache.http.wire=ERROR
Click Run
You get the following Response:
2015/02/03 19:23:36:495 EST [DEBUG] BasicClientConnectionManager - Get connection for route {s}->https://greenhouse.lotus.com
2015/02/03 19:23:36:831 EST [DEBUG] DefaultClientConnectionOperator - Connecting to greenhouse.lotus.com:443
2015/02/03 19:23:37:099 EST [DEBUG] RequestAddCookies - CookieSpec selected: best-match
2015/02/03 19:23:37:109 EST [DEBUG] RequestAuthCache - Auth cache not set in the context
2015/02/03 19:23:37:110 EST [DEBUG] RequestTargetAuthentication - Target auth state: UNCHALLENGED
2015/02/03 19:23:37:113 EST [DEBUG] RequestProxyAuthentication - Proxy auth state: UNCHALLENGED
2015/02/03 19:23:37:113 EST [DEBUG] DefaultHttpClient - Attempt 1 to execute request
2015/02/03 19:23:37:113 EST [DEBUG] DefaultClientConnection - Sending request: GET /forums/atom/forums HTTP/1.1
2015/02/03 19:23:37:114 EST [DEBUG] headers - >> GET /forums/atom/forums HTTP/1.1
2015/02/03 19:23:37:115 EST [DEBUG] headers - >> Host: greenhouse.lotus.com
2015/02/03 19:23:37:115 EST [DEBUG] headers - >> Connection: Keep-Alive
2015/02/03 19:23:37:115 EST [DEBUG] headers - >> User-Agent: Apache-HttpClient/4.3.3 (java 1.5)
2015/02/03 19:23:37:115 EST [DEBUG] headers - >> Authorization: Basic <<REMOVED>>
2015/02/03 19:23:37:287 EST [DEBUG] DefaultClientConnection - Receiving response: HTTP/1.1 200 OK
2015/02/03 19:23:37:287 EST [DEBUG] headers - << HTTP/1.1 200 OK
2015/02/03 19:23:37:288 EST [DEBUG] headers - << Date: Wed, 04 Feb 2015 00:14:04 GMT
2015/02/03 19:23:37:288 EST [DEBUG] headers - << X-Powered-By: Servlet/3.0
2015/02/03 19:23:37:288 EST [DEBUG] headers - << X-LConn-Auth: false
2015/02/03 19:23:37:288 EST [DEBUG] headers - << X-UA-Compatible: IE=9,8
2015/02/03 19:23:37:288 EST [DEBUG] headers - << Expires: Wed, 04 Feb 2015 00:14:04 GMT
2015/02/03 19:23:37:288 EST [DEBUG] headers - << Accept: application/atom+xml
2015/02/03 19:23:37:288 EST [DEBUG] headers - << Last-Modified: Wed, 04 Feb 2015/02/03 19:23:37:289 EST [DEBUG] headers - << Cache-Control: private, max-age=0, no-cache=set-cookie
2015/02/03 19:23:37:289 EST [DEBUG] headers - << Vary: User-Agent,Accept-Encoding
2015/02/03 19:23:37:290 EST [DEBUG] headers - << Keep-Alive: timeout=10, max=89
2015/02/03 19:23:37:290 EST [DEBUG] headers - << Connection: Keep-Alive
2015/02/03 19:23:37:290 EST [DEBUG] headers - << Transfer-Encoding: chunked
2015/02/03 19:23:37:290 EST [DEBUG] headers - << Content-Type: application/atom+xml;charset=UTF-8
2015/02/03 19:23:37:290 EST [DEBUG] headers - << Content-Language: en-US
2015/02/03 19:23:37:383 EST [DEBUG] BasicClientConnectionManager - Releasing connection org.apache.http.impl.conn.ManagedClientConnectionImpl@1372ed45
2015/02/03 19:23:37:383 EST [DEBUG] BasicClientConnectionManager - Connection can be kept alive for 10000 MILLISECONDS
+F: my forum
+F: Lotus Greenhouse
+F: test
+F: Connections 5.0 with CR1 and Portal 8.0.0.1 with CF14
+F: StandAloneForum1
If you want to dig into more and want more debugging, you can change the debug strings. I tend to use this particular string when debugging, be sure to turn it off when you are in production (it’s super chatty).
-Dorg.apache.commons.logging.Log=org.apache.commons.logging.impl.SimpleLog -Dorg.apache.commons.logging.simplelog.showdatetime=true -Dorg.apache.commons.logging.simplelog.log.org.apache.http=DEBUG
You can also do this with Maven projects. You should review your Maven build, or change your run settings or test settings to reflect the custom JVM parameters. Also, you can do this in WebSphere Application Server, however you risk getting extra noise from other Applications or Ajax Proxies.
I hope this helps you all during debugging.
Addendum (2015 NOV 21)
For those that need to set the logging values for Apache Tomcat (across the board), add “org.apache.http.level = FINEST” to the end of the conf\logging.properties file. You need to restart Tomcat, and then look at the catalina.out file.
As many of you know, I am Java Programmer and a cURL fan. When I am demonstrating an API to a customer or another IBMer, I tend to default to either method to demonstrate the API.
I was demonstrating a download API that was being redirected, and throwing an error on a different Node. In order to debug the traffic, I used a couple of different methods.
1 – For Java
I added -Djavax.net.debug=ssl:handshake:verbose to the Java VM Arguments. In Eclipse, I configure the Run Configuration -> VM Arguments.
java -Djavax.net.debug=ssl:handshake:verbose MyAPIDemo
I absolutely make sure you have enough buffer in your console window. I right click and update to a 100,000 lines. I like to keep it as high as possible to capture all the details.
Scroll Through the output and find out what actually happened in the request.
2 – For cURL
I add -vv which is super verbose to the command
curl -H "Authorization: Basic asdfljkfasdf" https://api.com/api -vv
I read through and find out why my API failed.
You can read more about the configuration in the IBM JDK Documentation.