Add options for global exclusion patterns (#7648)

* Add options for global exclusion patterns

* address

Author: ofek

disk/assets/configuration/spec.yaml

@@ -4,6 +4,32 @@ files:
     example_name: conf.yaml.default
     options:
       - template: init_config
+        options:
+          - name: file_system_global_blacklist
+            description: |
+              Instruct the check to always add these patterns to `file_system_blacklist`.
+            value:
+              example:
+                - iso9660$
+              type: array
+              items:
+                type: string
+          - name: device_global_blacklist
+            description: |
+              Instruct the check to always add these patterns to `device_blacklist`.
+            value:
+              example: []
+              type: array
+              items:
+                type: string
+          - name: mount_point_global_blacklist
+            description: |
+              Instruct the check to always add these patterns to `mount_point_blacklist`.
+            value:
+              example: []
+              type: array
+              items:
+                type: string
       - template: instances
         options:
           - name: use_mount
@@ -23,7 +49,7 @@ files:
           - name: file_system_whitelist
             description: |
               Instruct the check to only collect from matching file systems.
-             
+
               Character casing is ignored. For convenience, the regular expressions
               start matching from the beginning and therefore to match anywhere you
               must prepend `.*`. For exact matches append `$`.

disk/datadog_checks/disk/data/conf.yaml.default

@@ -1,6 +1,22 @@
 ## All options defined here are available to all instances.
 #
-# init_config: {}
+init_config:
+
+    ## @param file_system_global_blacklist - list of strings - optional
+    ## Instruct the check to always add these patterns to `file_system_blacklist`.
+    #
+    # file_system_global_blacklist:
+    #   - iso9660$
+
+    ## @param device_global_blacklist - list of strings - optional
+    ## Instruct the check to always add these patterns to `device_blacklist`.
+    #
+    # device_global_blacklist: []
+
+    ## @param mount_point_global_blacklist - list of strings - optional
+    ## Instruct the check to always add these patterns to `mount_point_blacklist`.
+    #
+    # mount_point_global_blacklist: []
 
 ## Every instance is scheduled independent of the others.
 #

disk/datadog_checks/disk/disk.py

@@ -292,10 +292,13 @@ def collect_latency_metrics(self):
                 self.log.debug('Latency metrics not collected for %s: %s', disk_name, e)
 
     def _compile_pattern_filters(self, instance):
-        # Force exclusion of CDROM (iso9660)
-        file_system_blacklist_extras = ['iso9660$']
-        device_blacklist_extras = []
-        mount_point_blacklist_extras = []
+        file_system_blacklist_extras = self.init_config.get(
+            'file_system_global_blacklist', self.get_default_file_system_blacklist()
+        )
+        device_blacklist_extras = self.init_config.get('device_global_blacklist', self.get_default_device_blacklist())
+        mount_point_blacklist_extras = self.init_config.get(
+            'mount_point_global_blacklist', self.get_default_mount_mount_blacklist()
+        )
 
         deprecation_message = '`%s` is deprecated and will be removed in a future release. Please use `%s` instead.'
 
@@ -421,3 +424,18 @@ def _get_devices_label_from_blkid_cache(self):
                 )
 
         return devices_label
+
+    @staticmethod
+    def get_default_file_system_blacklist():
+        return [
+            # CDROM
+            'iso9660$',
+        ]
+
+    @staticmethod
+    def get_default_device_blacklist():
+        return []
+
+    @staticmethod
+    def get_default_mount_mount_blacklist():
+        return []