Add config to set target database for metric query (#450)

tembo-operator/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "controller"
 description = "Tembo Operator for Postgres"
-version = "0.29.0"
+version = "0.29.1"
 edition = "2021"
 default-run = "controller"
 license = "Apache-2.0"

tembo-operator/src/app_service/ingress.rs

@@ -262,7 +262,7 @@ pub fn generate_ingress_tcp_routes(
             let mut routes: Vec<IngressRouteTCPRoutes> = Vec::new();
             for route in routings.iter() {
                 match route.ingress_path.clone() {
-                    Some(path) => {
+                    Some(_path) => {
                         if !route.ingress_type.clone()?.eq(&IngressType::tcp) {
                             // Do not create IngressRouteTCPRoutes for non-TCP ingress type
                             debug!("Skipping IngressRouteTCPRoutes for non-TCP ingress type");

tembo-operator/src/defaults.rs

@@ -65,6 +65,10 @@ pub fn default_postgres_exporter_image() -> String {
     "quay.io/prometheuscommunity/postgres-exporter:v0.12.0".to_owned()
 }
 
+pub fn default_postgres_exporter_target_databases() -> Vec<String> {
+    vec!["postgres".to_owned()]
+}
+
 pub fn default_extensions() -> Vec<Extension> {
     vec![]
 }

tembo-operator/src/lib.rs

@@ -47,6 +47,9 @@ pub enum Error {
     #[error("SerializationError: {0}")]
     SerializationError(#[source] serde_json::Error),
 
+    #[error("SerializationError: {0}")]
+    YamlSerializationError(#[source] serde_yaml::Error),
+
     #[error("Kube Error: {0}")]
     KubeError(#[from] kube::Error),
 
@@ -71,3 +74,9 @@ impl Error {
         format!("{self:?}").to_lowercase()
     }
 }
+
+impl From<serde_yaml::Error> for Error {
+    fn from(err: serde_yaml::Error) -> Self {
+        Error::YamlSerializationError(err)
+    }
+}

tembo-operator/src/postgres_exporter.rs

@@ -108,6 +108,8 @@ pub struct Metrics {
 ///          - total_messages:
 ///              description: Total number of messages that have passed into the queue.
 ///              usage: GAUGE
+///        target_databases:
+///          - "postgres"
 /// ```
 #[derive(Clone, Debug, JsonSchema, PartialEq, Serialize, Deserialize)]
 pub struct QueryItem {
@@ -131,6 +133,16 @@ pub struct QueryItem {
     /// description: the metric's description
     /// metrics_mapping: the optional column mapping when usage is set to MAPPEDMETRIC
     pub metrics: Vec<Metrics>,
+
+    /// The default database can always be overridden for a given user-defined
+    /// metric, by specifying a list of one or more databases in the target_databases
+    /// option.
+    ///
+    /// See: [https://cloudnative-pg.io/documentation/1.20/monitoring/#example-of-a-user-defined-metric-running-on-multiple-databases](https://cloudnative-pg.io/documentation/1.20/monitoring/#example-of-a-user-defined-metric-running-on-multiple-databases)
+    ///
+    /// **Default:** `["postgres"]`
+    #[serde(default = "defaults::default_postgres_exporter_target_databases")]
+    pub target_databases: Vec<String>,
 }
 
 #[derive(Clone, Debug, JsonSchema, PartialEq, Serialize, Deserialize)]
@@ -185,7 +197,7 @@ pub async fn reconcile_metrics_configmap(cdb: &CoreDB, client: Client, ns: &str)
     // directly and not through the reconcile function.
     match cdb.spec.metrics.clone().and_then(|m| m.queries) {
         Some(queries) => {
-            let qdata = serde_yaml::to_string(&queries).unwrap();
+            let qdata = serde_yaml::to_string(&queries)?;
             let d: BTreeMap<String, String> = BTreeMap::from([(QUERIES.to_string(), qdata)]);
             apply_configmap(
                 client.clone(),
@@ -196,7 +208,7 @@ pub async fn reconcile_metrics_configmap(cdb: &CoreDB, client: Client, ns: &str)
             .await?
         }
         None => {
-            debug!("No queries specified in CoreDB spec");
+            debug!("No queries specified in CoreDB spec {}", coredb_name);
         }
     }
     Ok(())
@@ -223,7 +235,8 @@ mod tests {
                         "description": "Time at which postmaster started"
                       }
                     }
-                  ]
+                  ],
+                  "target_databases": ["postgres"]
                 },
                 "extensions": {
                   "query": "select count(*) as num_ext from pg_available_extensions",
@@ -235,7 +248,8 @@ mod tests {
                         "description": "Num extensions"
                       }
                     }
-                  ]
+                  ],
+                  "target_databases": ["postgres"]
                 }
               }
         );
@@ -286,13 +300,17 @@ mod tests {
   - num_ext:
       usage: GAUGE
       description: Num extensions
+  target_databases:
+  - postgres
 pg_postmaster:
   query: SELECT pg_postmaster_start_time as start_time_seconds from pg_postmaster_start_time()
   master: true
   metrics:
   - start_time_seconds:
       usage: GAUGE
       description: Time at which postmaster started
+  target_databases:
+  - postgres
 "#;
         // formmatted correctly as yaml (for configmap)
         assert_eq!(yaml, data);

tembo-operator/src/stacks/templates/message_queue.yaml

@@ -95,6 +95,8 @@ postgres_metrics:
         - total_messages:
             usage: GAUGE
             description: Total number of messages that have passed into the queue.
+      target_databases:
+        - "postgres"
 postgres_config_engine: mq
 postgres_config:
   - name: shared_preload_libraries

tembo-operator/yaml/sample-message-queue.yaml

@@ -55,7 +55,7 @@ spec:
     image: quay.io/prometheuscommunity/postgres-exporter:v0.12.0
     queries:
       pgmq:
-        query: select queue_name, queue_length, oldest_msg_age_sec, newest_msg_age_sec, total_messages from public.pgmq_metrics_all()
+        query: select queue_name, queue_length, oldest_msg_age_sec, newest_msg_age_sec, total_messages from pgmq.metrics_all()
         master: true
         metrics:
           - queue_name:
@@ -73,6 +73,8 @@ spec:
           - total_messages:
               description: Total number of messages that have passed into the queue.
               usage: GAUGE
+        target_databases:
+          - "postgres"
   runtime_config:
     - name: shared_buffers
       value: "1024MB"