stx control stop: faster shutdown

Make sure aptly & builder containers catch and handle SIGTERM. Otherwise
"stx stop" sends the signal, 2 out of 6 containers ignore it, then
docker waits for ~15 seconds and SIGKILL's them.

* stx-builder.Dockerfile: change default image command from plain "bash"
  to "tini" that starts "sleep infinity". Tini catches and broadcasts
  signals to its own children (sleep), enabling graceful shutdown to
  work

* aptly: replace call to "supervisord" to "exec supervisord", to make
  sure it runs as PID 1 and actually receives signals from docker.

* stx_control.py: slightly reduce loop sleep time in "stx control stop"

TESTS
==================
* Retest "stx control start --wait"
* Make sure builder's entry point executes "finisSetup.sh" script, as
  before this change
* Make sure "stx control stop --wait" exits quickly (~4 seconds on my
  machine, down from ~15 seconds)

Story: 2011038
Task: 49577

Signed-off-by: Davlet Panech <davlet.panech@windriver.com>
Change-Id: I984846fc45349be045c069b84186f12179fe36ad

stx/dockerfiles/stx-builder.Dockerfile

@@ -51,6 +51,7 @@ RUN apt-get update && apt-get install --no-install-recommends -y \
         rpm2cpio \
         ssh \
         sudo \
+        tini \
         unzip \
         vim \
         wget \
@@ -97,3 +98,6 @@ RUN apt-key add /root/pubkey.rsa && rm -f /root/pubkey.rsa
 RUN mkdir -p /etc/vim
 COPY stx/toCOPY/common/vimrc.local /etc/vim/vimrc.local
 RUN chmod 0644 /etc/vim/vimrc.local
+
+ENTRYPOINT ["/usr/bin/tini", "-g", "--"]
+CMD ["/bin/bash", "-i", "-c", "exec /bin/sleep infinity" ]

stx/lib/stx/k8s.py

@@ -80,7 +80,7 @@ class KubeHelper:
                                          suffix='.stderr') as stderr_file:
             cmd = f'{self.config.kubectl()} get pods --no-headers'
             cmd += f' --selector=app.kubernetes.io/instance={project_name} 2>{stderr_file.name}'
-            process_result = subprocess.run(cmd, shell=True, stdout=subprocess.PIPE)
+            process_result = subprocess.run(cmd, encoding='utf-8', shell=True, stdout=subprocess.PIPE)
             if process_result.returncode != 0:
                 logger.error('Command failed: %s\n%s', cmd, stderr_file.fread())
                 raise RuntimeError("Failed to list pods")

stx/lib/stx/stx_control.py

@@ -306,7 +306,7 @@ stx-pkgbuilder/configmap/')
                     self.logger.warning("gave up while pods are still running")
                     break
                 self.logger.info("waiting for %d pod(s) to exit", pod_count)
-                time.sleep(3)
+                time.sleep(2)
 
     def handleIsStartedTask(self, projectname):
         if self.k8s.helm_release_exists(projectname):

stx/toCOPY/aptly/entrypoint.sh

@@ -39,4 +39,4 @@ else
 fi
 
 # Start Supervisor
-/usr/bin/supervisord -n -c /etc/supervisor/supervisord.conf
+exec /usr/bin/supervisord -n -c /etc/supervisor/supervisord.conf