copr: add generating prometheus metrics to frontend

roles/copr/frontend/files/monitoring.py

@@ -0,0 +1,49 @@
+#! /usr/bin/python3
+
+import requests
+from bs4 import BeautifulSoup
+from prometheus_client import CollectorRegistry, write_to_textfile, Gauge
+
+
+class TextfileCollector:
+    NAGIOS_URL = 'https://nagios.fedoraproject.org/nagios/cgi-bin//avail.cgi'
+
+    def __init__(self, url, name, documentation, css_selector, filename):
+        self.registry = CollectorRegistry()
+        self.url = url
+        self.css_selector = css_selector
+        self.filename = filename
+        self.copr_cdn_status = Gauge(name, documentation, registry=self.registry)
+
+    def collect_data(self):
+        url = self.NAGIOS_URL + self.url
+        r = requests.get(url)
+        html = r.text
+        soup = BeautifulSoup(html, features="lxml")
+        service_ok = soup.select_one(self.css_selector)
+        return service_ok.text.strip('%')
+
+    def set(self, data):
+        self.copr_cdn_status.set(data)
+        write_to_textfile(self.filename, self.registry)
+
+
+def collect(url, name, documentation, css_selector, filename):
+    textfile_collector = TextfileCollector(url, name, documentation, css_selector, filename)
+    percentage = textfile_collector.collect_data()
+    textfile_collector.set(percentage)
+
+
+if __name__ == '__main__':
+    copr_cdn_url = "?t1=1641301793&t2=1641388193&show_log_entries=&full_log_entries=&" \
+                   "host=copr-fe.aws.fedoraproject.org&service=The+copr+cdn+status&assumeinitialstates=yes&" \
+                   "assumestateretention=yes&assumestatesduringnotrunning=yes&includesoftstates=no&" \
+                   "initialassumedhoststate=0&initialassumedservicestate=0&timeperiod=last31days&backtrack=4"
+    copr_ping_url = "?t1=1628506451&t2=1629111251&show_log_entries=&host=copr-be.aws.fedoraproject.org&" \
+                    "service=The+copr-ping+package+builds&assumeinitialstates=yes&assumestateretention=yes&" \
+                    "assumestatesduringnotrunning=yes&includesoftstates=no&initialassumedhoststate=0&" \
+                    "initialassumedservicestate=0&timeperiod=last31days&backtrack=4"
+    collect(copr_cdn_url, "copr_cdn_status", "Copr's CDN status", "td.serviceOK:nth-child(4)",
+            "/var/lib/node_exporter/textfile_collector/copr_cdn_status.prom.new")
+    collect(copr_ping_url, "copr_ping_status", "Status of build of copr-ping package", "td.serviceOK:nth-child(4)",
+            "/var/lib/node_exporter/textfile_collector/copr_ping_status.prom.new")

roles/copr/frontend/tasks/main.yml

@@ -29,6 +29,53 @@
   tags:
   - packages
 
+- name: Configure cron job for generating prometheus metrics hourly
+  when: production|bool
+  cron:
+    name: "generating prometheus metrics"
+    user: root
+    minute: 0
+    job: /usr/bin/python3 monitoring.py
+  tags:
+  - cron_tasks
+
+- name: Deploy the prometheus monitoring script
+  when: production|bool
+  copy:
+    src: monitoring.py
+    dest: /usr/bin/monitoring.py
+    mode: 0750
+    owner: root
+    group: root
+  tags:
+  - cron_tasks
+
+- name: Check that file copr_cdn_status.prom.new exists
+  when: production|bool
+  stat: path=/var/lib/node_exporter/textfile_collector/copr_cdn_status.prom.new
+  register: copr_cdn_status_stat
+  tags:
+    - cron_tasks
+
+- name: Rename copr_cdn_status.prom.new to copr_cdn_status.prom
+  command: mv /var/lib/node_exporter/textfile_collector/copr_cdn_status.prom.new /var/lib/node_exporter/textfile_collector/copr_cdn_status.prom
+  when: copr_cdn_status_stat.stat.exists and production|bool
+  tags:
+    - cron_tasks
+
+- name: Check that file copr_ping_status.prom.new exists
+  when: production|bool
+  stat: path=/var/lib/node_exporter/textfile_collector/copr_ping_status.prom.new
+  register: copr_ping_status_stat
+  tags:
+    - cron_tasks
+
+- name: Rename copr_ping_status.prom.new to copr_ping_status.prom
+  command: mv /var/lib/node_exporter/textfile_collector/copr_ping_status.prom.new /var/lib/node_exporter/textfile_collector/copr_ping_status.prom
+  when: copr_ping_status_stat.stat.exists and production|bool
+  tags:
+    - cron_tasks
+
   # we install python-alembic because https://bugzilla.redhat.com/show_bug.cgi?id=1536058
 - name: install additional pkgs for copr-frontend
   dnf:
@@ -41,6 +88,7 @@
       - python3-alembic
       - mod_auth_gssapi
       - nagios-plugins-http
+      - python3-prometheus_client
   tags:
   - packages