task(observability): Enable UWSGI status endpoint and metrics for mul…

…tiple workers (#301)

* task(observability): Adopt new base image

* enable uwsgi status endpoint to export metrics through sidecar later

* adding config to track metrics for different worker pids

* correct name of the folder

* add logrotate (it was supposed to be available on the parent img)

Dockerfile

@@ -1,19 +1,20 @@
 # To run: docker run -v /path/to/wsgi.py:/var/www/indexd/wsgi.py --name=indexd -p 81:80 indexd
 # To check running container: docker exec -it indexd /bin/bash
 
-FROM quay.io/cdis/python-nginx:pybase3-1.4.1
+FROM quay.io/cdis/python-nginx:pybase3-1.4.2
 
 
 ENV appname=indexd
 
 RUN apk update \
     && apk add postgresql-libs postgresql-dev libffi-dev libressl-dev \
     && apk add linux-headers musl-dev gcc \
-    && apk add curl bash git vim
+    && apk add curl bash git vim logrotate
 
 COPY . /$appname
 COPY ./deployment/uwsgi/uwsgi.ini /etc/uwsgi/uwsgi.ini
 COPY ./deployment/uwsgi/wsgi.py /$appname/wsgi.py
+COPY clear_prometheus_multiproc /$appname/clear_prometheus_multiproc
 WORKDIR /$appname
 
 RUN python -m pip install --upgrade pip \

clear_prometheus_multiproc

@@ -0,0 +1,7 @@
+#!/bin/bash
+set -ex
+
+rm -Rf $1
+mkdir $1
+chmod 755 $1
+chown 100:101 $1

deployment/uwsgi/uwsgi.ini

@@ -21,6 +21,10 @@ wsgi-file=/indexd/wsgi.py
 plugins = python3
 vacuum = true
 pythonpath = /indexd/
+stats = 127.0.0.1:9191
+stats-http = true
+env = prometheus_multiproc_dir=/var/tmp/uwsgi_flask_metrics
+exec-asap = /indexd/clear_prometheus_multiproc /var/tmp/uwsgi_flask_metrics
 # Initialize application in worker processes, not master. This prevents the
 # workers from all trying to open the same database connections at startup.
 lazy = true