# Managing an Application ## Track Application Changes Deis Workflow tracks all changes to your application. Application changes are the result of either new application code pushed to the platform (via `git push deis master`), or an update to application configuration (via `deis config:set KEY=VAL`). Each time a build or config change is made to your application a new [release][] is created. These release numbers increase montonically. You can see a record of changes to your application using `deis releases`: ``` $ deis releases === peachy-waxworks Releases v4 3 minutes ago gabrtv deployed d3ccc05 v3 1 hour 17 minutes ago gabrtv added DATABASE_URL v2 6 hours 2 minutes ago gabrtv deployed 7cb3321 v1 6 hours 2 minutes ago gabrtv deployed deis/helloworld ``` ## Rollback a Release Deis Workflow also supports rolling back go previous releases. If buggy code or an errant configuration change is pushed to your application, you may rollback to a previously known, good release. !!! note All rollbacks create a new, numbered release. But will reference the build/code and configuration from the desired rollback point. In this example, the application is currently running release v4. Using `deis rollback v2` tells Workflow to deploy the build and configuration that was used for release v2. This creates a new release named v5 whose contents are the source and configuration from release v2: ``` $ deis releases === folksy-offshoot Releases v4 4 minutes ago gabrtv deployed d3ccc05 v3 1 hour 18 minutes ago gabrtv added DATABASE_URL v2 6 hours 2 minutes ago gabrtv deployed 7cb3321 v1 6 hours 3 minutes ago gabrtv deployed deis/helloworld $ deis rollback v2 Rolled back to v2 $ deis releases === folksy-offshoot Releases v5 Just now gabrtv rolled back to v2 v4 4 minutes ago gabrtv deployed d3ccc05 v3 1 hour 18 minutes ago gabrtv added DATABASE_URL v2 6 hours 2 minutes ago gabrtv deployed 7cb3321 v1 6 hours 3 minutes ago gabrtv deployed deis/helloworld ``` ## Run One-off Administration Tasks Deis applications [use one-off processes for admin tasks][] like database migrations and other commands that must run against the live application. Use `deis run` to execute commands on the deployed application. $ deis run 'ls -l' Running `ls -l`... total 28 -rw-r--r-- 1 root root 553 Dec 2 23:59 LICENSE -rw-r--r-- 1 root root 60 Dec 2 23:59 Procfile -rw-r--r-- 1 root root 33 Dec 2 23:59 README.md -rw-r--r-- 1 root root 1622 Dec 2 23:59 pom.xml drwxr-xr-x 3 root root 4096 Dec 2 23:59 src -rw-r--r-- 1 root root 25 Dec 2 23:59 system.properties drwxr-xr-x 6 root root 4096 Dec 3 00:00 target ## Share an Application Use `deis perms:create` to allow another Deis user to collaborate on your application. ``` $ deis perms:create otheruser Adding otheruser to peachy-waxworks collaborators... done ``` Use `deis perms` to see who an application is currently shared with, and `deis perms:remove` to remove a collaborator. !!! note Collaborators can do anything with an application that its owner can do, except delete the application. When working with an application that has been shared with you, clone the original repository and add Deis' git remote entry before attempting to `git push` any changes to Deis. ``` $ git clone https://github.com/deis/example-java-jetty.git Cloning into 'example-java-jetty'... done $ cd example-java-jetty $ git remote add -f deis ssh://git@local3.deisapp.com:2222/peachy-waxworks.git Updating deis From deis-controller.local:peachy-waxworks * [new branch] master -> deis/master ``` ## Application Troubleshooting Applications deployed on Deis Workflow [treat logs as event streams][]. Deis Workflow aggregates `stdout` and `stderr` from every [Container][] making it easy to troubleshoot problems with your application. Use `deis logs` to view the log output from your deployed application. $ deis logs | tail Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.5]: INFO:oejsh.ContextHandler:started o.e.j.s.ServletContextHandler{/,null} Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.8]: INFO:oejs.Server:jetty-7.6.0.v20120127 Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.5]: INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:10005 Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.6]: INFO:oejsh.ContextHandler:started o.e.j.s.ServletContextHandler{/,null} Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.7]: INFO:oejsh.ContextHandler:started o.e.j.s.ServletContextHandler{/,null} Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.6]: INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:10006 Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.8]: INFO:oejsh.ContextHandler:started o.e.j.s.ServletContextHandler{/,null} Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.7]: INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:10007 Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.8]: INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:10008 [application]: ../reference-guide/terms.md#application [container]: ../reference-guide/terms.md#container [store config in environment variables]: http://12factor.net/config [decoupled from the application]: http://12factor.net/backing-services [scale out via the process model]: http://12factor.net/concurrency [treat logs as event streams]: http://12factor.net/logs [use one-off processes for admin tasks]: http://12factor.net/admin-processes [Procfile]: http://ddollar.github.io/foreman/#PROCFILE