WIP: Added DNS check.

.gitignore

@@ -1,2 +1,3 @@
 *.pyc
 configuration.yaml
+env/

ping_exporter/dns_ping.py

@@ -0,0 +1,98 @@
+import types
+import dns.resolver
+
+wanted_attributes = ['dns_server', 'status_code', 'ok']
+
+def _example_hook(resp, *args, **kwargs):
+    resp.example = 'example'
+
+
+def _exception_handler(request, exception):
+    obj = types.SimpleNamespace()
+    for attr in wanted_attributes:
+        obj.__setattr__(attr, None)
+        if attr == 'url':
+            obj.url = request.url
+        if attr == 'exception':
+            obj.exception = exception.__doc__
+        if attr == 'ok':
+            obj.ok = False
+    return obj
+
+
+def _serialize_return_values(blub):
+    for wauw in blub:
+        for attr in wanted_attributes:
+            if wauw[attr] is None:
+                wauw[attr] = 'Nan'
+            if wauw[attr] is True:
+                wauw[attr] = 1
+            if wauw[attr] is False:
+                wauw[attr] = 0
+
+
+def dns_ping(dnsendpoints, all=True, serialize=True):
+    from ping_exporter.main import get_config_from_argv
+    data = []
+
+    for server,domain in dnsendpoints.items():
+        response_data = {}
+        query = dns.message.make_query(domain,dns.rdatatype.A)
+        res = dns.query.tcp(query,server,timeout=2)
+        response_data['dns_server'] = server
+        response_data['status_code'] = res.rcode()
+        response_data['ok'] = True if res.rcode() == 0 else False
+
+        data.append(response_data)
+
+    if all:
+        response_data = {}
+        for item in wanted_attributes:
+            response_data.update({item: None})
+            if item == 'dns_server':
+                response_data[item] = 'all'
+            if item == 'status_code':
+                response_data[item] = 'NaN'
+            if item == 'ok':
+                response_data[item] = sum([x['ok'] for x in data])
+        data.append(response_data)
+
+    if serialize:
+        _serialize_return_values(data)
+    return data
+
+#    for response in grequests.map(
+#            rs,
+#            exception_handler=_exception_handler,
+#            size=config.get('pool_size', 2)):
+#        response_data = {}
+#        if response is not None:
+#            for item in wanted_attributes:
+#                try:
+#                    if item == 'elapsed':
+#                        response_data.update(
+#                            {item:
+#                             response.__getattribute__(item).total_seconds()})
+#                        continue
+#                    response_data.update(
+#                        {item: response.__getattribute__(item)})
+#                except AttributeError:
+#                    response_data.update({item: None})
+#
+#        data.append(response_data)
+#
+#    if all:
+#        response_data = {}
+#        for item in wanted_attributes:
+#            response_data.update({item: None})
+#            if item == 'url':
+#                response_data[item] = 'all'
+#            if item == 'elapsed':
+#                response_data[item] = time
+#            if item == 'ok':
+#                response_data[item] = any([x['ok'] for x in data])
+#        data.append(response_data)
+#
+#    if serialize:
+#        _serialize_return_values(data)
+#    return data

ping_exporter/prometheus_metrics.py

@@ -1,4 +1,5 @@
 from ping_exporter.ping import pong, wanted_attributes
+from ping_exporter.dns_ping import dns_ping
 
 
 def generate_name(prefix, extra_tags=None):
@@ -68,6 +69,6 @@ def make_prometheus_text(return_values):
 
 
 def prometheus_text(config):
-    return_values = pong(config['endpoints'])
+    return_values = pong(config['endpoints']) + dns_ping(config['dns'])
     lines = make_prometheus_text(return_values)
     return "\n".join(lines)

requirements.txt

@@ -2,3 +2,4 @@ flask==1.1.1
 grequests==0.4.0
 pyyaml==5.1.2
 gunicorn==19.9.0
+dnspython==2.1.0

tests/test_dnsping.py

@@ -0,0 +1,22 @@
+from ping_exporter.dns_ping import dns_ping
+
+
+def test_dns_ping_without_endpoints_returns_empty_all_object(mocker):
+    mocker_argv = mocker.patch('ping_exporter.main.get_config_from_argv')
+    mocker_argv.return_value = ({}, None)
+
+    expected = [{'dns_server': 'all', 'status_code': 'NaN', 'ok': 0}]
+
+    assert expected == dns_ping({})
+
+    expected = []
+    assert expected == dns_ping({}, all=False)
+
+def test_dns_ping_with_endpoints_returns_empty_all_object(mocker):
+    mocker_argv = mocker.patch('ping_exporter.main.get_config_from_argv')
+    mocker_argv.return_value = ({}, None)
+
+    rv = dns_ping({'8.8.8.8': 'google.com', '1.1.1.1': 'cloudflare.com'})
+
+    assert rv[0]['ok'] is 1
+    assert 0 == rv[0]['status_code']

tests/test_prometheus_metrics.py

@@ -23,7 +23,7 @@ def test_prometheus_text(mocker):
     mock_main_get_config_from_argv = mocker.patch('ping_exporter.main.get_config_from_argv')
     mock_main_get_config_from_argv.return_value = ({}, None)
 
-    text_lines = prometheus_text({'endpoints': []}).splitlines()
+    text_lines = prometheus_text({'endpoints': [], 'dns': {}}).splitlines()
     assert text_lines[0].startswith('# TYPE')
     assert text_lines[1].startswith('# HELP')
     assert text_lines[2].startswith('probe_')