Add -M flag to map non-numeric perfdata values

README.md

@@ -66,15 +66,14 @@ usage: check_http_json.py [-h] [-d] [-s] -H HOST [-k] [-V] [--cacert CACERT]
                           [-y [KEY_VALUE_LIST_NOT [KEY_VALUE_LIST_NOT ...]]]
                           [-Y [KEY_VALUE_LIST_NOT_CRITICAL [KEY_VALUE_LIST_NOT_CRITICAL ...]]]
                           [-m [METRIC_LIST [METRIC_LIST ...]]]
+                          [-M KEY=VALUE]
 
 Check HTTP JSON Nagios Plugin
 
 Generic Nagios plugin which checks json values from a given endpoint against
 argument specified rules and determines the status and performance data for
 that service.
 
-Version: 2.2.0 (2024-05-14)
-
 options:
   -h, --help            show this help message and exit
   -d, --debug           debug mode
@@ -125,7 +124,7 @@ options:
                         (key[>alias],value key2,value2) to determine status.
                         Multiple key values can be delimited with colon
                         (key,value1:value2). Return warning if the key is older
-                        than the value (ex.: 30s,10m,2h,3d,...). 
+                        than the value (ex.: 30s,10m,2h,3d,...).
                         With at it return warning if the key is jounger
                         than the value (ex.: @30s,@10m,@2h,@3d,...).
                         With Minus you can shift the time in the future.
@@ -144,6 +143,8 @@ options:
                         performance data. More information about Range format and units of measure for nagios can be found at nagios-
                         plugins.org/doc/guidelines.html Additional formats for this parameter are: (key[>alias]),
                         (key[>alias],UnitOfMeasure), (key[>alias],UnitOfMeasure,WarnRange, CriticalRange).
+  -M KEY=VALUE          Map the values of the gathered metric to the given values. This can be used to map non-numeric values to numeric values, e.g. -M
+                        Up=1. Can used multiple times. This flag is meant to be used with the -m flag.
 ```
 
 The check plugin respects the environment variables `HTTP_PROXY`, `HTTPS_PROXY`.
@@ -255,6 +256,28 @@ The check plugin respects the environment variables `HTTP_PROXY`, `HTTPS_PROXY`.
 
 More info about Nagios Range format and Units of Measure can be found at [https://nagios-plugins.org/doc/guidelines.html](https://nagios-plugins.org/doc/guidelines.html).
 
+### Performance Data Metrics
+
+The `-m` and `-M` flags can be used to generate performance data from the JSON data.
+
+```
+check_http_json.py -H host.internal --path example-data.json -e 'service.requests' -m 'service.requests'
+OK: 'service.requests'=12  Status OK. |'service.requests'=12
+
+check_http_json.py -H host.internal --path example-data.json -e 'service.requests' -m 'service.requests>webshopRequests,c'
+OK: 'webshopRequests'=12c  Status OK. |'webshopRequests'=12c
+```
+
+The `-M` flag can be used to map non-numeric values to numeric values.
+
+```
+check_http_json.py -H host.internal --path example-data.json -e 'service.status' -m 'service.status'
+OK: 'service.status'=Up  Status OK. |'service.requests'=Up
+
+check_http_json.py -H host.internal --path example-data.json -e 'service.status' -m 'service.status' -M Up=1
+OK: 'service.status'=1  Status OK. |'service.requests'=1
+```
+
 ### Timestamp
 
 **Data**:

check_http_json.py

@@ -441,10 +441,12 @@ def checkMetrics(self):
         Return a Nagios specific performance metrics string given keys
         and parameter definitions
         """
-
         metrics = ''
         warning = ''
         critical = ''
+
+        kv = dict(self.rules.metric_value_mapping) if hasattr(self.rules, 'metric_value_mapping') else {}
+
         if self.metric_list is not None:
             for metric in self.metric_list:
                 key = metric
@@ -461,7 +463,10 @@ def checkMetrics(self):
                             minimum, maximum = vals
                 key, alias = _getKeyAlias(key)
                 if self.helper.exists(key):
-                    metrics += "'%s'=%s" % (alias, self.helper.get(key))
+                    value = self.helper.get(key)
+                    # Apply the value mapping if it exists
+                    v = kv.get(str(value), value)
+                    metrics += "'%s'=%s" % (alias, v)
                     if uom:
                         metrics += uom
                     if warn_range is not None:
@@ -481,7 +486,6 @@ def checkMetrics(self):
                 metrics += ' '
         return ("%s" % metrics, warning, critical)
 
-
 def parseArgs(args):
     """
     CLI argument definitions and parsing
@@ -608,10 +612,26 @@ def parseArgs(args):
                         (key[>alias]), (key[>alias],UnitOfMeasure),
                         (key[>alias],UnitOfMeasure,WarnRange,
                         CriticalRange).''')
+    parser.add_argument('-M', dest='metric_value_mapping', metavar="KEY=VALUE",
+                        type=key_value_pair,
+                        action="append",
+                        default=[],
+                        help='''Map the values of the gathered metric to the given values.
+                        This can be used to map non-numeric values to numeric values, e.g. -M Up=1. Can used multiple times.
+                        This flag is meant to be used with the -m flag.''')
 
     return parser.parse_args(args)
 
 
+def key_value_pair(value):
+    """
+    Small helper to split key=value arguments into a tuple.
+    """
+    parts = value.split('=', 1)
+    if len(parts) != 2:
+        raise argparse.ArgumentTypeError('invalid format %s. Expected key=value' % (value))
+    return (parts[0], parts[1])
+
 def debugPrint(debug_flag, message):
     """
     Print debug messages if -d is set.

test/test_args.py

@@ -32,3 +32,7 @@ def test_parser_with_separator(self):
         parser = parseArgs(['-H', 'foobar', '-f', '_', '-F', '_'])
         self.assertEqual(parser.separator, '_')
         self.assertEqual(parser.value_separator, '_')
+
+    def test_parser_with_value_mapping(self):
+        parser = parseArgs(['-H', 'foobar', '-M', 'key=value'])
+        self.assertEqual(parser.metric_value_mapping, [('key', 'value')])

test/test_check_http_json.py

@@ -234,6 +234,40 @@ def test_critical_thresholds(self):
         self.check_data(RulesHelper().dash_c(['(*).value,@1:5']),
                         '[{"value": 5},{"value": 1000}]', CRITICAL_CODE)
 
+    def test_metrics_value_mapping(self):
+        data = json.loads('{"status": "Up"}')
+        expected = ("'status'=0 ", '', '')
+
+        processor = JsonRuleProcessor(data, parseArgs(['-H', 'foobar', '-m', 'status', '-M', 'Up=0']))
+        actual = processor.checkMetrics()
+
+        self.assertEqual(actual, expected)
+
+        data = json.loads('{"status": "Down"}')
+        expected = ("'status'=1 ", '', '')
+
+        processor = JsonRuleProcessor(data, parseArgs(['-H', 'foobar', '-m', 'status', '-M', 'Up=0', '-M', 'Down=1']))
+        actual = processor.checkMetrics()
+
+        self.assertEqual(actual, expected)
+
+    def test_metrics_value_mapping_datatypes(self):
+        data = json.loads('{"status": "123"}')
+        expected = ("'status'=foo ", '', '')
+        # Test with string value as target
+        processor = JsonRuleProcessor(data, parseArgs(['-H', 'foobar', '-m', 'status', '-M', '123=foo']))
+        actual = processor.checkMetrics()
+
+        self.assertEqual(actual, expected)
+
+        data = json.loads('{"status": 123}')
+        expected = ("'status'=foo ", '', '')
+        # Test with string value as source and target
+        processor = JsonRuleProcessor(data, parseArgs(['-H', 'foobar', '-m', 'status', '-M', '123=foo']))
+        actual = processor.checkMetrics()
+
+        self.assertEqual(actual, expected)
+
     def test_separator(self):
         rules = RulesHelper()
         rules.separator = '_'