Use standard output for alarm logs

[daisy-ycguo]

The image built based on Dockerfile in the root folder is not runnable now because /logs/alarmsTrigger_logs.log is not exist.

Below changes are an option to fix this issue.

--- a/Dockerfile
+++ b/Dockerfile
@@ -16,10 +16,11 @@ RUN apt-get update --fix-missing && \
 # only package.json
 ADD package.json /alarmsTrigger/
 RUN cd /alarmsTrigger; npm install
+RUN touch ~/alarmsTrigger_logs.log

 # App
 ADD provider/. /alarmsTrigger/

 EXPOSE 8080

-CMD ["/bin/bash", "-c", "node /alarmsTrigger/app.js >> /logs/alarmsTrigger_logs.log 2>&1"]
+CMD ["/bin/bash", "-c", "node /alarmsTrigger/app.js >> ~/alarmsTrigger_logs.log 2>&1"]

[daisy-ycguo]

We'd better use standard output for alarm trigger logs. That's easier for operators to manage than writing to a log file, because docker logs and kubectl logs can show the standard output messages.

[jasonpet]

You simply need to create a /logs volume on your docker run command. For example: -v /var/wsklogs/alarmsTrigger:/logs