feat(postgres): Postgres Connection Test score now has a script that provides more insight. Not quite working properly but easy to improve at this point.

harmony/src/modules/postgresql/score_connect.rs

@@ -4,9 +4,7 @@ use k8s_openapi::api::core::v1::Secret;
 use log::{debug, error, info, trace};
 use serde::Serialize;
 use std::collections::BTreeMap;
-use std::io::Write;
 use std::path::{Path, PathBuf};
-use std::process::Stdio;
 use tokio::process::Command;
 
 use crate::data::Version;
@@ -16,6 +14,47 @@ use crate::score::Score;
 use crate::topology::{K8sclient, Topology};
 use harmony_types::id::Id;
 
+/// PostgreSQLConnectionScore tests PostgreSQL database connectivity and performance metrics
+/// for databases exposed via public endpoints. This score is specifically designed to verify
+/// that PostgreSQL instances installed using the PublicPostgreSQLScore can be accessed by external clients.
+///
+/// The score performs the following tests:
+/// 1. Verifies TLS/SSL connection using CA certificates from Kubernetes secrets
+/// 2. Tests basic connectivity to the database
+/// 3. (Optional, when db permissions are setup) Collects comprehensive performance metrics including :
+///    - Database size and schema usage statistics
+///    - Active connections and query activity
+///    - Performance metrics (transactions per second, cache hit ratio)
+///    - Index usage and table statistics
+///    - Configuration parameters
+///
+/// The implementation uses a Docker container running PostgreSQL client tools to execute
+/// the connection test, ensuring consistent behavior across different environments.
+///
+/// # Kubernetes Secrets Required
+///
+/// The score requires two Kubernetes secrets in the target namespace:
+/// - `{cluster_name}-app`: Contains connection parameters (host, port, username, password, dbname)
+/// - `{cluster_name}-ca`: Contains CA certificate (ca.crt) for TLS verification
+///
+/// # Usage
+///
+/// ```rust
+/// use harmony::modules::postgresql::PostgreSQLConnectionScore;
+///
+/// let score = PostgreSQLConnectionScore::new(
+///     "default",
+///     "my-postgres-cluster",
+///     None
+/// );
+/// ```
+///
+/// # Parameters
+///
+/// - `namespace`: Kubernetes namespace where the PostgreSQL secrets are located
+/// - `cluster_name`: Name of the PostgreSQL cluster (used to construct secret names)
+/// - `hostname_override`: Optional hostname override for connection testing
+/// - `port_override`: Optional port override for connection testing
 #[derive(Debug, Clone, Serialize)]
 pub struct PostgreSQLConnectionScore {
     pub name: String,
@@ -143,31 +182,13 @@ impl PostgreSQLConnectionInterpret {
             .ok_or_else(|| InterpretError::new("Port not found in secret or override".to_string()))
     }
 
-    fn create_test_script(
+    fn create_test_script(&self, temp_dir: &Path) -> Result<PathBuf, InterpretError> {
-        &self,
-        temp_dir: &Path,
-        ca_file: &Path,
-        username: &str,
-        password: &str,
-        dbname: &str,
-        host: &str,
-        port: u16,
-    ) -> Result<PathBuf, InterpretError> {
         let script_path = temp_dir.join("test_connection.sh");
-        let ca_file_in_container = Path::new("/tmp").join(ca_file.file_name().unwrap());
-        let script_content = format!(
-            "#!/bin/sh\n\\
-            psql \"host={} port={} user={} dbname={} sslmode=verify-ca sslrootcert={} sslnegotiation=direct\" -c \"SELECT 1\"",
-            host,
-            port,
-            username,
-            dbname,
-            ca_file_in_container.display()
-        );
 
-        debug!("Wrote script content : \n{script_content}");
+        let script_content = postgres_scipt_content();
         std::fs::write(&script_path, script_content)
             .map_err(|e| InterpretError::new(format!("Failed to write test script: {e}")))?;
+        debug!("Wrote script content : \n{script_content}");
 
         #[cfg(unix)]
         {
@@ -187,13 +208,15 @@ impl PostgreSQLConnectionInterpret {
     async fn run_docker_test(
         &self,
         temp_dir: &Path,
-        script_path: &Path,
+        cmd: &str,
         password: &str,
     ) -> Result<Outcome, InterpretError> {
         info!("Running connection test in Docker container...");
+        let container_cmd = format!("PGPASSWORD={} /tmp/test_connection.sh {}", password, cmd);
+        debug!("Starting docker container with cmd : {container_cmd}");
 
-        let output = Command::new("docker")
+        let mut cmd = Command::new("docker");
-            .arg("run")
+        cmd.arg("run")
             .arg("--rm")
             .arg("-i")
             .arg("-v")
@@ -204,10 +227,12 @@ impl PostgreSQLConnectionInterpret {
             .arg("/bin/sh")
             .arg("postgres:latest")
             .arg("-c")
-            .arg(format!("PGPASSWORD={} /tmp/test_connection.sh", password))
+            .arg(container_cmd)
             .env("PGPASSWORD", password)
             .stdout(std::process::Stdio::inherit())
-            .stderr(std::process::Stdio::inherit())
+            .stderr(std::process::Stdio::inherit());
+        debug!("Running Command {cmd:?}");
+        let output = cmd
             .spawn()
             .map_err(|e| InterpretError::new(format!("Failed to spawn docker container: {e}")))?
             .wait_with_output()
@@ -220,11 +245,11 @@ impl PostgreSQLConnectionInterpret {
             info!("Successfully connected to PostgreSQL!");
             Ok(Outcome::success("Connection successful".to_string()))
         } else {
+            let stdout = String::from_utf8_lossy(&output.stdout);
             let stderr = String::from_utf8_lossy(&output.stderr);
-            error!("Connection failed: {}", stderr);
+            error!("Connection failed: stdout:\n{stdout}\nstderr:\n{stderr}");
             Err(InterpretError::new(format!(
-                "Connection failed: {}",
+                "Connection failed: stdout:\n{stdout}\nstderr:\n{stderr}",
-                stderr
             )))
         }
     }
@@ -277,23 +302,141 @@ impl<T: Topology + K8sclient + Send + Sync> Interpret<T> for PostgreSQLConnectio
         let host = self.get_host(&app_data)?;
         let port = self.get_port(&app_data)?;
 
-
         // Create test script
-        let script_path = self.create_test_script(
+        let script_path = self.create_test_script(temp_dir_path)?;
-            temp_dir_path,
-            &ca_file,
-            &username,
-            &password,
-            &dbname,
-            &host,
-            port,
-        )?;
 
+        let ca_file_in_container = Path::new("/tmp").join(ca_file.file_name().unwrap());
+        let script_cmd = format!(
+            "{host} {port} {username} {dbname} {}",
+            ca_file_in_container.display()
+        );
         debug!("Prepared test script in {}", temp_dir_path.display());
-        tokio::time::sleep(std::time::Duration::from_secs(10)).await;
-
         // Run connection test
-        self.run_docker_test(temp_dir_path, &script_path, &password)
+        self.run_docker_test(temp_dir_path, &script_cmd, &password)
             .await
     }
 }
+
+fn postgres_scipt_content() -> &'static str {
+    r#"
+#!/bin/sh
+# PostgreSQL connection test and metrics collection script
+
+# Basic connectivity test
+echo "=== CONNECTION TEST ==="
+psql "host=$1 port=$2 user=$3 dbname=$4 sslmode=verify-ca sslrootcert=$5 sslnegotiation=direct" -c "SELECT 1" > /dev/null 2>&1
+if [ $? -ne 0 ]; then
+    echo "ERROR: Connection failed"
+    exit 1
+fi
+echo "Connection successful"
+
+# Database size metrics
+echo -e "\n=== DATABASE SIZE METRICS ==="
+echo "Total database size (MB):"
+psql "host=$1 port=$2 user=$3 dbname=$4 sslmode=verify-ca sslrootcert=$5 sslnegotiation=direct" -c "SELECT pg_size_pretty(pg_database_size(current_database()))" -t -A
+
+echo "Database size breakdown:"
+psql "host=$1 port=$2 user=$3 dbname=$4 sslmode=verify-ca sslrootcert=$5 sslnegotiation=direct" -c "SELECT
+    schema_name,
+    pg_size_pretty(sum(table_size)) as total_size
+FROM (
+    SELECT
+        n.nspname as schema_name,
+        c.relname as table_name,
+        pg_total_relation_size(c.oid) as table_size
+    FROM pg_class c
+    LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
+    WHERE n.nspname NOT IN ('pg_catalog', 'information_schema')
+    AND c.relkind = 'r'
+) t
+GROUP BY schema_name
+ORDER BY sum(table_size) DESC" -t
+
+# Connection and activity metrics
+echo -e "\n=== CONNECTION & ACTIVITY ==="
+echo "Active connections:"
+psql "host=$1 port=$2 user=$3 dbname=$4 sslmode=verify-ca sslrootcert=$5 sslnegotiation=direct" -c "SELECT count(*) FROM pg_stat_activity" -t -A
+
+echo "Current queries (running longer than 1 second):"
+psql "host=$1 port=$2 user=$3 dbname=$4 sslmode=verify-ca sslrootcert=$5 sslnegotiation=direct" -c "SELECT
+    pid,
+    usename,
+    query_start,
+    now() - query_start as duration,
+    state,
+    left(query, 50) as query_preview
+FROM pg_stat_activity
+WHERE state = 'active' AND now() - query_start > interval '1 second'
+ORDER BY duration DESC" -t
+
+# Performance metrics
+echo -e "\n=== PERFORMANCE METRICS ==="
+echo "Database load (transactions per second):"
+psql "host=$1 port=$2 user=$3 dbname=$4 sslmode=verify-ca sslrootcert=$5 sslnegotiation=direct" -c "SELECT
+    tps,
+    tps_commit,
+    tps_rollback,
+    blks_read,
+    blks_hit,
+    hit_ratio
+FROM (
+    SELECT
+        xact_commit as tps_commit,
+        xact_rollback as tps_rollback,
+        (xact_commit + xact_rollback) as tps,
+        blks_read,
+        blks_hit,
+        CASE WHEN blks_read + blks_hit = 0 THEN 0 ELSE (blks_hit * 100.0 / (blks_read + blks_hit))::numeric(5,2) END as hit_ratio
+    FROM pg_stat_database
+    WHERE datname = current_database()
+) stats" -t
+
+echo "Current locks:"
+psql "host=$1 port=$2 user=$3 dbname=$4 sslmode=verify-ca sslrootcert=$5 sslnegotiation=direct" -c "SELECT
+    count(*) as lock_count,
+    string_agg(mode, ', ' ORDER BY mode) as lock_modes
+FROM pg_locks" -t
+
+# Table statistics
+echo -e "\n=== TABLE STATISTICS ==="
+echo "Most accessed tables:"
+psql "host=$1 port=$2 user=$3 dbname=$4 sslmode=verify-ca sslrootcert=$5 sslnegotiation=direct" -c "SELECT
+    relname,
+    seq_scan,
+    idx_scan,
+    n_tup_ins,
+    n_tup_upd,
+    n_tup_del
+FROM pg_stat_user_tables
+ORDER BY seq_scan + idx_scan + n_tup_ins + n_tup_upd + n_tup_del DESC
+LIMIT 10" -t
+
+# Index usage
+echo -e "\n=== INDEX USAGE ==="
+echo "Index usage statistics:"
+psql "host=$1 port=$2 user=$3 dbname=$4 sslmode=verify-ca sslrootcert=$5 sslnegotiation=direct" -c "SELECT
+    indexrelname as index_name,
+    idx_scan,
+    idx_tup_read,
+    idx_tup_fetch
+FROM pg_stat_user_indexes
+ORDER BY idx_scan DESC
+LIMIT 5" -t
+
+# Configuration and limits
+echo -e "\n=== CONFIGURATION ==="
+echo "Current database parameters:"
+psql "host=$1 port=$2 user=$3 dbname=$4 sslmode=verify-ca sslrootcert=$5 sslnegotiation=direct" -c "SELECT
+    name,
+    setting,
+    unit
+FROM pg_settings
+WHERE category = 'Resource Usage'
+ORDER BY name" -t
+
+echo -e "\n=== TEST COMPLETE ==="
+echo "All metrics collected successfully"
+exit 0
+"#
+}