Run post build hook with /bin/sh -ic

We need either `/bin/bash -c` or `/bin/sh -ic` to make our supported
SCL-powered images to work properly. That's due to a hack to auto-enable
SCLs:
https://github.com/openshift/sti-base/blob/8d95148/Dockerfile#L23-L29

In CentOS and RHEL images, `/bin/sh` is a symlink to `/bin/bash`. In
that case, the ENV environment variable is only evaluated when the shell
is started in interactive mode, which happens when there's and attached
tty (not the case for post build hook) or when the `-i` argument is
passed explicitly.

Making the shell interactive with `-i` is ugly, but is the only solution
we know so far without requiring Bash.

examples/sample-app/application-template-dockerbuild.json

@@ -144,6 +144,9 @@
  "name": "origin-ruby-sample:latest"
  }
  },
+ "postCommit": {
+ "script": "bundle exec rake test"
+ },
  "resources": {}
  },
  "status": {

examples/sample-app/application-template-pullspecbuild.json

@@ -136,6 +136,9 @@
  "name": "origin-ruby-sample:latest"
  }
  },
+ "postCommit": {
+ "script": "bundle exec rake test"
+ },
  "resources": {}
  },
  "status": {

examples/sample-app/application-template-stibuild.json

@@ -146,6 +146,9 @@
  "name": "origin-ruby-sample:latest"
  }
  },
+ "postCommit": {
+ "script": "bundle exec rake test"
+ },
  "resources": {}
  },
  "status": {

pkg/build/api/types.go

@@ -441,7 +441,7 @@ type SourceBuildStrategy struct {
 // The above is a convenient form which is equivalent to:
 //
 // BuildPostCommitSpec{
-// Command: []string{"/bin/sh", "-c"},
+// Command: []string{"/bin/sh", "-ic"},
 // Args: []string{"rake test --verbose"},
 // }
 //
@@ -486,19 +486,24 @@ type SourceBuildStrategy struct {
 // the fields are specified, the hook is not executed.
 type BuildPostCommitSpec struct {
  // Command is the command to run. It may not be specified with Script.
- // This might be needed if the image doesn't have "/bin/sh", or if you
+ // This might be needed if the image doesn't have `/bin/sh`, or if you
  // do not want to use a shell. In all other cases, using Script might be
  // more convenient.
  Command []string
  // Args is a list of arguments that are provided to either Command,
  // Script or the Docker image's default entrypoint. The arguments are
  // placed immediately after the command to be run.
  Args []string
- // Script is a shell script to be run with `/bin/sh -c`. It may not be
+ // Script is a shell script to be run with `/bin/sh -ic`. It may not be
  // specified with Command. Use Script when a shell script is appropriate
  // to execute the post build hook, for example for running unit tests
- // with "rake test". If you need control over the image entrypoint, or
- // if the image does not have "/bin/sh", use Command and/or Args.
+ // with `rake test`. If you need control over the image entrypoint, or
+ // if the image does not have `/bin/sh`, use Command and/or Args.
+ // The `-i` flag is needed to support CentOS and RHEL images that use
+ // Software Collections (SCL), in order to have the appropriate
+ // collections enabled in the shell. E.g., in the Ruby image, this is
+ // necessary to make `ruby`, `bundle` and other binaries available in
+ // the PATH.
  Script string
 }
 

pkg/build/api/v1/types.go

@@ -424,7 +424,7 @@ type SourceBuildStrategy struct {
 // The above is a convenient form which is equivalent to:
 //
 // BuildPostCommitSpec{
-// Command: []string{"/bin/sh", "-c"},
+// Command: []string{"/bin/sh", "-ic"},
 // Args: []string{"rake test --verbose"},
 // }
 //
@@ -469,19 +469,24 @@ type SourceBuildStrategy struct {
 // the fields are specified, the hook is not executed.
 type BuildPostCommitSpec struct {
  // Command is the command to run. It may not be specified with Script.
- // This might be needed if the image doesn't have "/bin/sh", or if you
+ // This might be needed if the image doesn't have `/bin/sh`, or if you
  // do not want to use a shell. In all other cases, using Script might be
  // more convenient.
  Command []string `json:"command,omitempty" description:"command to be executed in a container running the build output image replacing the image's entrypoint"`
  // Args is a list of arguments that are provided to either Command,
  // Script or the Docker image's default entrypoint. The arguments are
  // placed immediately after the command to be run.
  Args []string `json:"args,omitempty" description:"arguments to command, script or the default image entrypoint"`
- // Script is a shell script to be run with `/bin/sh -c`. It may not be
+ // Script is a shell script to be run with `/bin/sh -ic`. It may not be
  // specified with Command. Use Script when a shell script is appropriate
  // to execute the post build hook, for example for running unit tests
- // with "rake test". If you need control over the image entrypoint, or
- // if the image does not have "/bin/sh", use Command and/or Args.
+ // with `rake test`. If you need control over the image entrypoint, or
+ // if the image does not have `/bin/sh`, use Command and/or Args.
+ // The `-i` flag is needed to support CentOS and RHEL images that use
+ // Software Collections (SCL), in order to have the appropriate
+ // collections enabled in the shell. E.g., in the Ruby image, this is
+ // necessary to make `ruby`, `bundle` and other binaries available in
+ // the PATH.
  Script string `json:"script,omitempty" description:"shell script to be executed in a container running the build output image"`
 }
 

pkg/build/api/v1beta3/types.go

@@ -411,7 +411,7 @@ type SourceBuildStrategy struct {
 // The above is a convenient form which is equivalent to:
 //
 // BuildPostCommitSpec{
-// Command: []string{"/bin/sh", "-c"},
+// Command: []string{"/bin/sh", "-ic"},
 // Args: []string{"rake test --verbose"},
 // }
 //
@@ -456,19 +456,24 @@ type SourceBuildStrategy struct {
 // the fields are specified, the hook is not executed.
 type BuildPostCommitSpec struct {
  // Command is the command to run. It may not be specified with Script.
- // This might be needed if the image doesn't have "/bin/sh", or if you
+ // This might be needed if the image doesn't have `/bin/sh`, or if you
  // do not want to use a shell. In all other cases, using Script might be
  // more convenient.
  Command []string `json:"command,omitempty" description:"command to be executed in a container running the build output image replacing the image's entrypoint"`
  // Args is a list of arguments that are provided to either Command,
  // Script or the Docker image's default entrypoint. The arguments are
  // placed immediately after the command to be run.
  Args []string `json:"args,omitempty" description:"arguments to command, script or the default image entrypoint"`
- // Script is a shell script to be run with `/bin/sh -c`. It may not be
+ // Script is a shell script to be run with `/bin/sh -ic`. It may not be
  // specified with Command. Use Script when a shell script is appropriate
  // to execute the post build hook, for example for running unit tests
- // with "rake test". If you need control over the image entrypoint, or
- // if the image does not have "/bin/sh", use Command and/or Args.
+ // with `rake test`. If you need control over the image entrypoint, or
+ // if the image does not have `/bin/sh`, use Command and/or Args.
+ // The `-i` flag is needed to support CentOS and RHEL images that use
+ // Software Collections (SCL), in order to have the appropriate
+ // collections enabled in the shell. E.g., in the Ruby image, this is
+ // necessary to make `ruby`, `bundle` and other binaries available in
+ // the PATH.
  Script string `json:"script,omitempty" description:"shell script to be executed in a container running the build output image"`
 }
 

pkg/build/builder/common.go

@@ -135,7 +135,12 @@ func execPostCommitHook(client DockerClient, postCommitSpec api.BuildPostCommitS
  glog.V(4).Infof("Post commit hook spec: %+v", postCommitSpec)
 
  if script != "" {
- command = []string{"/bin/sh", "-c"}
+ // The `-i` flag is needed to support CentOS and RHEL images
+ // that use Software Collections (SCL), in order to have the
+ // appropriate collections enabled in the shell. E.g., in the
+ // Ruby image, this is necessary to make `ruby`, `bundle` and
+ // other binaries available in the PATH.
+ command = []string{"/bin/sh", "-ic"}
  args = append([]string{script, command[0]}, args...)
  }