Do not require bash to be installed in docker containers.

Tutor is not using any bash-specific feature.
This commit changes (almost) all invocations to /bin/bash replacing them with
/bin/sh. It allows building a docker image that does not bundle bash in it.

The file k8s.py still has a bash invocation, to make sure this change does not
impact functionality for any user.

tutor/k8s.py

@@ -66,7 +66,7 @@ def delete(yes):
 )
 @opts.root
 def databases(root):
-    scripts.migrate(root, run_bash)
+    scripts.migrate(root, run_sh)
 
 
 @click.command(help="Create an Open edX user and interactively set their password")
@@ -76,14 +76,14 @@ def databases(root):
 @click.argument("name")
 @click.argument("email")
 def createuser(root, superuser, staff, name, email):
-    scripts.create_user(root, run_bash, superuser, staff, name, email)
+    scripts.create_user(root, run_sh, superuser, staff, name, email)
 
 
 @click.command(help="Import the demo course")
 @opts.root
 def importdemocourse(root):
     click.echo(fmt.info("Importing demo course"))
-    scripts.import_demo_course(root, run_bash)
+    scripts.import_demo_course(root, run_sh)
     click.echo(fmt.info("Re-indexing courses"))
     indexcourses.callback(root)
 
@@ -93,7 +93,7 @@ def importdemocourse(root):
 def indexcourses(root):
     # Note: this is currently broken with "pymongo.errors.ConnectionFailure: [Errno 111] Connection refused"
     # I'm not quite sure the settings are correctly picked up. Which is weird because migrations work very well.
-    scripts.index_courses(root, run_bash)
+    scripts.index_courses(root, run_sh)
 
 
 @click.command(
@@ -176,8 +176,8 @@ class K8s:
         kubectl_no_fail("exec", "--namespace", self.NAMESPACE, "-it", podname, "--", *command)
 
 
-def run_bash(root, service, command):  # pylint: disable=unused-argument
-    K8s().execute(service, "bash", "-e", "-c", command)
+def run_sh(root, service, command):  # pylint: disable=unused-argument
+    K8s().execute(service, "sh", "-e", "-c", command)
 
 
 k8s.add_command(quickstart)

tutor/local.py

@@ -129,7 +129,7 @@ def run(root, service, command, args):
 @opts.root
 def databases(root):
     init_mysql(root)
-    scripts.migrate(root, run_bash)
+    scripts.migrate(root, run_sh)
 
 
 def init_mysql(root):
@@ -247,7 +247,7 @@ def logs(root, follow, tail, service):
 def createuser(root, superuser, staff, name, email):
     config = tutor_config.load(root)
     check_service_is_activated(config, "lms")
-    scripts.create_user(root, run_bash, superuser, staff, name, email)
+    scripts.create_user(root, run_sh, superuser, staff, name, email)
 
 
 @click.command(help="Import the demo course")
@@ -256,7 +256,7 @@ def importdemocourse(root):
     config = tutor_config.load(root)
     check_service_is_activated(config, "cms")
     click.echo(fmt.info("Importing demo course"))
-    scripts.import_demo_course(root, run_bash)
+    scripts.import_demo_course(root, run_sh)
     click.echo(fmt.info("Re-indexing courses"))
     indexcourses.callback(root)
 
@@ -266,7 +266,7 @@ def importdemocourse(root):
 def indexcourses(root):
     config = tutor_config.load(root)
     check_service_is_activated(config, "cms")
-    scripts.index_courses(root, run_bash)
+    scripts.index_courses(root, run_sh)
 
 
 @click.command(
@@ -292,9 +292,9 @@ def check_service_is_activated(config, service):
         raise exceptions.TutorError("This command may only be executed on the server where the {} is running".format(service))
 
 
-def run_bash(root, service, command):
+def run_sh(root, service, command):
     config = tutor_config.load(root)
-    docker_compose(root, config, "run", "--rm", service, "bash", "-e", "-c", command)
+    docker_compose(root, config, "run", "--rm", service, "sh", "-e", "-c", command)
 
 
 def docker_compose(root, config, *command):

tutor/templates/build/openedx/bin/docker-entrypoint.sh

@@ -1,4 +1,4 @@
-#!/bin/bash -e
+#!/bin/sh -e
 export DJANGO_SETTINGS_MODULE=$SERVICE_VARIANT.envs.$SETTINGS
 USERID=${USERID:=0}
 

tutor/templates/local/docker-compose.yml

@@ -49,7 +49,7 @@ services:
     image: {{ DOCKER_REGISTRY }}{{ DOCKER_IMAGE_OPENEDX }}
     volumes:
       - ../../data/openedx:/var/www/openedx
-    command: bash -c "rm -rf /var/www/openedx/staticfiles && cp -r /openedx/staticfiles/ /var/www/openedx/"
+    command: sh -c "rm -rf /var/www/openedx/staticfiles && cp -r /openedx/staticfiles/ /var/www/openedx/"
 
   nginx:
     image: {{ DOCKER_REGISTRY }}{{ DOCKER_IMAGE_NGINX }}