Chapter 10. Using images

Procedure

1. Log in to the OpenShift Container Platform web console using your login credentials. The default view for the OpenShift Container Platform web console is the Administrator perspective.
2. Use the perspective switcher to switch to the Developer perspective.
3. In the +Add view, use the Project drop-down list to select an existing project or create a new project.
4. Click All services in the Developer Catalog tile.
5. Click Builder Images under Type to see the available S2I images.

1. Runs the FROM <builder image> command
2. Copies the source code to a defined location in the builder image
3. Runs the assemble script in the builder image
4. Sets the run script in the builder image as the default command

Procedure

1. Look at the value of the io.openshift.s2i.scripts-url label to determine the location of the scripts inside of the builder image:

   $ podman inspect --format='{{ index .Config.Labels "io.openshift.s2i.scripts-url" }}' wildfly/wildfly-centos7

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   Example output

   image:///usr/libexec/s2i

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   You inspected the wildfly/wildfly-centos7 builder image and found out that the scripts are in the /usr/libexec/s2i directory.

2. Create a script that includes an invocation of one of the standard scripts wrapped in other commands:

   .s2i/bin/assemble script

   #!/bin/bash
   echo "Before assembling"
   
   /usr/libexec/s2i/assemble
   rc=$?
   
   if [ $rc -eq 0 ]; then
       echo "After successful assembling"
   else
       echo "After failed assembling"
   fi
   
   exit $rc

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   This example shows a custom assemble script that prints the message, runs the standard assemble script from the image, and prints another message depending on the exit code of the assemble script.

   Important

   When wrapping the run script, you must use exec for invoking it to ensure signals are handled properly. The use of exec also precludes the ability to run additional commands after invoking the default image run script.

   .s2i/bin/run script

   #!/bin/bash
   echo "Before running application"
   exec /usr/libexec/s2i/run

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