Add resolv.conf to forward list in coredns (#1625)

microk8s-resources/actions/coredns.yaml

@@ -32,7 +32,7 @@ data:
           fallthrough in-addr.arpa ip6.arpa
         }
         prometheus :9153
-        forward . 8.8.8.8 8.8.4.4
+        forward . $NAMESERVERS
         cache 30
         loop
         reload

microk8s-resources/actions/enable.dns.sh

@@ -3,10 +3,40 @@
 set -e
 
 source $SNAP/actions/common/utils.sh
-
+KUBECTL="$SNAP/kubectl --kubeconfig=${SNAP_DATA}/credentials/client.config"
 # Apply the dns yaml
 # We do not need to see dns pods running at this point just give some slack
 echo "Enabling DNS"
+
+read -ra ARGUMENTS <<< "$1"
+if [[ ! -z "${ARGUMENTS[@]}" ]]
+then
+  nameservers="${ARGUMENTS[@]}"
+else
+  nameservers="8.8.8.8,8.8.4.4"
+fi
+
+# if none passed use resolv.conf
+if [[ $nameservers == "/etc/resolv.conf" ]]
+then
+   nameserver_str="/etc/resolv.conf"
+else
+  REGEX_IP_ADDR='^[0-9][0-9]*\.[0-9][0-9]*\.[0-9][0-9]*\.[0-9][0-9]*$'
+  # get ip addresses separated by , as a list
+  nameservers_list=(${nameservers//,/ })
+  nameserver_str=""
+  for nameserver in "${nameservers_list[@]}"
+  do
+    if [[ $nameserver =~ $REGEX_IP_ADDR ]]
+    then
+      nameserver_str="${nameserver_str}${nameserver} "
+    else
+      echo "Your input value ($nameserver) is not a valid IP address"
+      exit 1
+    fi
+  done
+fi
+
 echo "Applying manifest"
 ALLOWESCALATION="false"
 if grep  -e ubuntu /proc/version | grep 16.04 &> /dev/null
@@ -15,6 +45,7 @@ then
 fi
 declare -A map
 map[\$ALLOWESCALATION]="$ALLOWESCALATION"
+map[\$NAMESERVERS]="$nameserver_str"
 use_manifest coredns apply "$(declare -p map)"
 sleep 5
 

tests/test-addons.py

@@ -1,42 +1,42 @@
+import pytest
 import os
 import platform
-from subprocess import PIPE, STDOUT, CalledProcessError, check_call, run
-
-import pytest
 import sh
 import yaml
 
-from utils import (
-    microk8s_disable,
-    microk8s_enable,
-    microk8s_reset,
-    wait_for_namespace_termination,
-    wait_for_pod_state,
-)
 from validators import (
-    validate_ambassador,
-    validate_cilium,
     validate_dns_dashboard,
-    validate_fluentd,
-    validate_forward,
-    validate_gpu,
+    validate_storage,
     validate_ingress,
+    validate_ambassador,
+    validate_gpu,
     validate_istio,
+    validate_knative,
+    validate_registry,
+    validate_forward,
+    validate_metrics_server,
+    validate_fluentd,
     validate_jaeger,
     validate_keda,
-    validate_knative,
-    validate_kubeflow,
     validate_linkerd,
-    validate_metallb_config,
-    validate_metrics_server,
-    validate_multus,
-    validate_portainer,
-    validate_prometheus,
     validate_rbac,
-    validate_registry,
-    validate_storage,
+    validate_cilium,
+    validate_multus,
+    validate_kubeflow,
+    validate_metallb_config,
+    validate_prometheus,
     validate_traefik,
+    validate_coredns_config,
+    validate_portainer,
 )
+from utils import (
+    microk8s_enable,
+    wait_for_pod_state,
+    wait_for_namespace_termination,
+    microk8s_disable,
+    microk8s_reset,
+)
+from subprocess import PIPE, STDOUT, CalledProcessError, check_call, run
 
 
 class TestAddons(object):
@@ -335,15 +335,19 @@ class TestAddons(object):
         print("Disabling Portainer")
         microk8s_disable("portainer")
 
-    def test_backup_restore(self):
-        """
-        Test backup and restore commands.
-        """
-        print('Checking dbctl backup and restore')
-        if os.path.exists('backupfile.tar.gz'):
-            os.remove('backupfile.tar.gz')
-        check_call("/snap/bin/microk8s.dbctl --debug backup -o backupfile".split())
-        check_call("/snap/bin/microk8s.dbctl --debug restore backupfile.tar.gz".split())
+    @pytest.mark.skipif(
+        os.environ.get('UNDER_TIME_PRESSURE') == 'True',
+        reason="Skipping dns tests as we are under time pressure",
+    )
+    def test_dns_addon(self):
+        ip_ranges = "8.8.8.8,1.1.1.1"
+        print("Enabling DNS")
+        microk8s_enable("{}:{}".format("dns", ip_ranges), timeout_insec=500)
+        wait_for_pod_state("", "kube-system", "running", label="k8s-app=kube-dns")
+        print("Validating DNS config")
+        validate_coredns_config(ip_ranges)
+        print("Disabling DNS")
+        microk8s_disable("dns")
 
     def test_traefik(self):
         """
@@ -374,6 +378,16 @@ class TestAddons(object):
         print("Disabling keda")
         microk8s_disable("keda")
 
+    def test_backup_restore(self):
+        """
+        Test backup and restore commands.
+        """
+        print('Checking dbctl backup and restore')
+        if os.path.exists('backupfile.tar.gz'):
+            os.remove('backupfile.tar.gz')
+        check_call("/snap/bin/microk8s.dbctl --debug backup -o backupfile".split())
+        check_call("/snap/bin/microk8s.dbctl --debug restore backupfile.tar.gz".split())
+
 
 @pytest.mark.addon_args
 def test_invalid_addon():

tests/validators.py

@@ -490,18 +490,15 @@ def validate_metallb_config(ip_ranges="192.168.0.105"):
         assert ip_range in out
 
 
-def validate_traefik():
+def validate_coredns_config(ip_ranges="8.8.8.8,1.1.1.1"):
     """
-    Validate traefik
+    Validate dns
     """
-    wait_for_pod_state("", "traefik", "running", label="name=traefik-ingress-lb")
-
-
-def validate_portainer():
-    """
-    Validate portainer
-    """
-    wait_for_pod_state("", "portainer", "running", label="app.kubernetes.io/name=portainer")
+    out = kubectl("get configmap coredns -n kube-system -o jsonpath='{.data.Corefile}'")
+    expected_forward_val = "forward ."
+    for ip_range in ip_ranges.split(","):
+        expected_forward_val = expected_forward_val + " " + ip_range
+    assert expected_forward_val in out
 
 
 def validate_keda():
@@ -517,3 +514,17 @@ def validate_keda():
     scaledObject = kubectl("-n gonuts get scaledobject.keda.sh")
     assert "stan-scaledobject" in scaledObject
     kubectl("delete -f {}".format(manifest))
+
+
+def validate_traefik():
+    """
+    Validate traefik
+    """
+    wait_for_pod_state("", "traefik", "running", label="name=traefik-ingress-lb")
+
+
+def validate_portainer():
+    """
+    Validate portainer
+    """
+    wait_for_pod_state("", "portainer", "running", label="app.kubernetes.io/name=portainer")