push: Add method to remove a user-defined push rule from a Ruleset

crates/ruma-common/CHANGELOG.md

@@ -7,7 +7,9 @@ Breaking changes:
 
 Improvements:
 
-- Add method to update the server-default push rules in a `Ruleset`
+- Add convenience methods for `push::Ruleset`:
+  - To update the server-default push rules
+  - To remove a user-defined push rule
 
 # 0.11.3
 

crates/ruma-common/src/push.rs

@@ -311,6 +311,47 @@ impl Ruleset {
     pub fn get_actions<T>(&self, event: &Raw<T>, context: &PushConditionRoomCtx) -> &[Action] {
         self.get_match(event, context).map(|rule| rule.actions()).unwrap_or(&[])
     }
+
+    /// Removes a user-defined rule in the rule set.
+    ///
+    /// Returns an error if the parameters are invalid.
+    pub fn remove(
+        &mut self,
+        kind: RuleKind,
+        rule_id: impl AsRef<str>,
+    ) -> Result<(), RemovePushRuleError> {
+        let rule_id = rule_id.as_ref();
+
+        if let Some(rule) = self.get(kind.clone(), rule_id) {
+            if rule.is_server_default() {
+                return Err(RemovePushRuleError::ServerDefault);
+            }
+        } else {
+            return Err(RemovePushRuleError::NotFound);
+        }
+
+        match kind {
+            RuleKind::Override => {
+                self.override_.shift_remove(rule_id);
+            }
+            RuleKind::Underride => {
+                self.underride.shift_remove(rule_id);
+            }
+            RuleKind::Sender => {
+                self.sender.shift_remove(rule_id);
+            }
+            RuleKind::Room => {
+                self.room.shift_remove(rule_id);
+            }
+            RuleKind::Content => {
+                self.content.shift_remove(rule_id);
+            }
+            // This has been handled in the `self.get` call earlier.
+            RuleKind::_Custom(_) => unreachable!(),
+        }
+
+        Ok(())
+    }
 }
 
 /// A push rule is a single rule that states under what conditions an event should be passed onto a
@@ -901,6 +942,19 @@ where
     Ok(())
 }
 
+/// The error type returned when trying to remove a user-defined push rule from a `Ruleset`.
+#[derive(Debug, Error)]
+#[non_exhaustive]
+pub enum RemovePushRuleError {
+    /// The rule is a server-default rules and they can't be removed.
+    #[error("server-default rules cannot be removed")]
+    ServerDefault,
+
+    /// The rule was not found.
+    #[error("rule not found")]
+    NotFound,
+}
+
 #[cfg(test)]
 mod tests {
     use std::collections::BTreeMap;

crates/ruma-common/src/push/iter.rs

@@ -53,6 +53,11 @@ impl AnyPushRule {
         self.as_ref().rule_id()
     }
 
+    /// Whether the push rule is a server-default rule.
+    pub fn is_server_default(&self) -> bool {
+        self.as_ref().is_server_default()
+    }
+
     /// Check if the push rule applies to the event.
     ///
     /// # Arguments
@@ -168,6 +173,17 @@ impl<'a> AnyPushRuleRef<'a> {
         }
     }
 
+    /// Whether the push rule is a server-default rule.
+    pub fn is_server_default(self) -> bool {
+        match self {
+            Self::Override(rule) => rule.default,
+            Self::Underride(rule) => rule.default,
+            Self::Content(rule) => rule.default,
+            Self::Room(rule) => rule.default,
+            Self::Sender(rule) => rule.default,
+        }
+    }
+
     /// Check if the push rule applies to the event.
     ///
     /// # Arguments