CRaSH the shell for the JVM
- 2. An extensible command line for the JVM Julien Viet Alain Defrance Senior software engineer Software engineer eXo Platform eXo Platform @julienviet @alaindefrance
- 3. @julienviet @alaindefrance 10 years of Open Source 2 years of Open Source ■ eXo Platform 2008 ■ eXo Platform 2010 ■ Red Hat 2006 Various ■ JBoss 2002 ■ Develop social product Various ■ Portal stuff (JBoss / GateIn) ■ JCP a while ago 3
- 4. Project Open source LGPL: http://www.crashub.org CRaSH 1.0 – April 2012 CRaSH 1.1 – August 2012 CRaSH 1.2 – Soon (in release candidate)
- 5. What/Why? CLI are still relevant Ubiquitous Expressive: find . -name “*.java” -exec grep julien {} ; - print Made for us Trends: NoSQL, MS Powershell, Drupal, Jenkins, Cloud, etc… Fun!
- 6. Comparison with UN*X shell Same client interface But hosted by JVM ■ History ■ Java threads ■ Completion ■ JVM access ■ Command Line Editing ■ Options & Arguments ■ Pipes 6
- 7. Usage Runtime modes Get it from ■ Standalone ■ crashub download ■ Embedded (web app, Spring, ■ Maven Central dependency …) ■ Attach 7
- 8. Simple stack Native Client SSH Telnet Web Console Attach VisualVM Connectors CRaSH Groovy Commands
- 9. What you can do with CRaSH Swiss army knife Embed in your runtime Create your commands Monitoring tool Scripting And more…
- 10. Out of the box
- 11. Out of the box Install CRaSH Run CRaSH standalone CLI basics JVM base commands Test it online
- 12. The Swiss Knife
- 13. The Swiss Knife Attach CRaSH to JBoss Application Server Execute commands in the Application Server
- 15. Extend your runtime Embed CRaSH in a Spring web application Connect using remote protocol Develop a command to access Spring beans Add options and arguments to the command
- 16. Monitoring
- 17. Monitoring Attach to Tomcat with VisualVM Use JMX command pipes Create pipes Assemble in custom dashboard
- 18. Pipelined object stream jmx jmx get sort find <Void, ObjectName> <ObjectName, Map> <Map, Map>
- 19. Wrap up Multi facet, powerful and extensible Reach us [email protected] @crashub http://www.crashub.org Hackergarten hands on coding Tuesday
- 20. Q&A
Editor's Notes
- #7: In this part we will show you what you can get withCRaSH out of the box:1/ install crash2/ run crash3/ basic commands : system properties + thread ls
- #8: 1/ where to download crash2/ how to install standalone3/ standalone layout4/ run standalone5/ single word command : help6/ composite commands7/ system propls8/ filtered system propls with completion9/ thread ls + group + nameA/ thread top
- #9: 1/ attach to JBoss AS2/ JDBC example3/ JPA example
- #10: 1/ attach to Jboss AS72/ use log command to show we are executing in AS7 context3/ browse JNDI + filters4/ jdbc open + info + tables + table + select + insert5/ jpa entities + entity + select + where
- #11: 1/ take an existing command and clone it2/ show some real time stuff3/ program the Twitter command
- #12: 1/ deploy spring based in tomcat2/ spring ls3/ create commands and display service4/ get twitter from service5/ format output with print6/ turn script into commands with option and parameters
- #13: 1/ introduce more advanced CRaSH concepts : dashboards Command pipes Aggregation & Streaming
- #14: 1/ attach to tomcat with visualvm2/ jmx find to list everthing3/ jmx find with filters to get mbean subset4/ jmx get to retrieve statistics5/ jmx sort6/ put command in dashboard7/ add thread ls filtered to retain http threads and jvm ls8/ put load on server