Filter multiple fields

src/trace_listeners.rs

@@ -9,13 +9,18 @@ use tracing_subscriber::{
     registry::{LookupSpan, SpanRef},
 };
 
+#[derive(Clone, Debug)]
+struct FieldFilter {
+    name: String,
+    value: Option<String>,
+}
+
 #[derive(Clone, Debug)]
 pub struct Filters {
     filter_target: Option<String>,
     filter_name: Option<String>,
     filter_message: Option<String>,
-    filter_field: Option<String>,
-    filter_field_value: Option<String>,
+    filter_fields: Vec<FieldFilter>,
 }
 
 impl Filters {
@@ -24,8 +29,7 @@ impl Filters {
             filter_target: None,
             filter_name: None,
             filter_message: None,
-            filter_field: None,
-            filter_field_value: None,
+            filter_fields: Vec::new(),
         }
     }
 
@@ -45,13 +49,18 @@ impl Filters {
     }
 
     pub fn field(mut self, field: impl ToString) -> Self {
-        self.filter_field = Some(field.to_string());
+        self.filter_fields.push(FieldFilter {
+            name: field.to_string(),
+            value: None,
+        });
         self
     }
 
     pub fn field_value(mut self, field: impl ToString, value: impl ToString) -> Self {
-        self.filter_field = Some(field.to_string());
-        self.filter_field_value = Some(value.to_string());
+        self.filter_fields.push(FieldFilter {
+            name: field.to_string(),
+            value: Some(value.to_string()),
+        });
         self
     }
 
@@ -73,7 +82,7 @@ impl Filters {
 struct TraceListenerVisitor<'a> {
     filters: &'a Filters,
     right_message: bool,
-    right_field: bool,
+    right_fields: Vec<bool>,
 }
 
 impl<'a> TraceListenerVisitor<'a> {
@@ -81,13 +90,13 @@ impl<'a> TraceListenerVisitor<'a> {
         Self {
             filters,
             right_message: false,
-            right_field: false,
+            right_fields: vec![false; filters.filter_fields.len()],
         }
     }
 
     fn did_match(&self) -> bool {
         (self.filters.filter_message.is_none() || self.right_message)
-            && (self.filters.filter_field.is_none() || self.right_field)
+            && self.right_fields.iter().all(|right| *right)
     }
 }
 impl<'a> Visit for TraceListenerVisitor<'a> {
@@ -100,12 +109,17 @@ impl<'a> Visit for TraceListenerVisitor<'a> {
                 self.right_message = true;
             }
         }
-        if let Some(filter_field) = &self.filters.filter_field {
-            if field.name() == filter_field {
-                if let Some(filter_field_value) = &self.filters.filter_field_value {
-                    self.right_field = &value_str == filter_field_value;
+        for (filter_field, right) in self
+            .filters
+            .filter_fields
+            .iter()
+            .zip(self.right_fields.iter_mut())
+        {
+            if field.name() == filter_field.name {
+                if let Some(filter_field_value) = &filter_field.value {
+                    *right = &value_str == filter_field_value;
                 } else {
-                    self.right_field = true;
+                    *right = true;
                 }
             }
         }
@@ -254,8 +268,8 @@ impl<S: Subscriber + for<'lookup> LookupSpan<'lookup>> Layer<S> for SpanListener
 
 mod test {
     use super::*;
-    use tracing_subscriber::prelude::*;
     use tracing::info;
+    use tracing_subscriber::prelude::*;
 
     #[test]
     fn test_event_listener() {
@@ -263,8 +277,7 @@ mod test {
         let all_listener = EventListener::new(Filters::new().target(std::module_path!()));
         let msg_listener = EventListener::new(Filters::new().message("filter message"));
         let field_listener = EventListener::new(Filters::new().field("field"));
-        let field_value_listener =
-            EventListener::new(Filters::new().field_value("field", 1234));
+        let field_value_listener = EventListener::new(Filters::new().field_value("field", 1234));
         let msg_field_value_listener = EventListener::new(
             Filters::new()
                 .message("filter message")
@@ -326,4 +339,42 @@ mod test {
         assert_eq!(field_value_listener.get_count(), 2);
         assert_eq!(msg_field_value_listener.get_count(), 1);
     }
+
+    #[test]
+    fn test_filter_fields() {
+        let no_fields = EventListener::new(Filters::new());
+        let one_field = EventListener::new(Filters::new().field("field_one"));
+        let two_fields = EventListener::new(
+            Filters::new()
+                .field("field_one")
+                .field_value("field_two", "123"),
+        );
+        let subscriber = tracing_subscriber::registry()
+            .with(no_fields.clone())
+            .with(one_field.clone())
+            .with(two_fields.clone());
+        let _sub = tracing::subscriber::set_default(subscriber);
+
+        assert_eq!(no_fields.get_count(), 0);
+        assert_eq!(one_field.get_count(), 0);
+        assert_eq!(two_fields.get_count(), 0);
+
+        info!("no fields message");
+
+        assert_eq!(no_fields.get_count(), 1);
+        assert_eq!(one_field.get_count(), 0);
+        assert_eq!(two_fields.get_count(), 0);
+
+        info!(field_one = 123, "one field message");
+
+        assert_eq!(no_fields.get_count(), 2);
+        assert_eq!(one_field.get_count(), 1);
+        assert_eq!(two_fields.get_count(), 0);
+
+        info!(field_one = 123, field_two = 123, "two field message");
+
+        assert_eq!(no_fields.get_count(), 3);
+        assert_eq!(one_field.get_count(), 2);
+        assert_eq!(two_fields.get_count(), 1);
+    }
 }