Server fully owns ClickHouse schema — create database + tables on startup

ClickHouseConfig.ensureDatabaseExists() connects without the database path
to run CREATE DATABASE IF NOT EXISTS before the main DataSource is used.
Removes the ConfigMap-based init scripts from the K8s manifest — the server
is now the single owner of all ClickHouse schema management.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

cameleer3-server-app/src/main/java/com/cameleer3/server/app/config/ClickHouseConfig.java

@@ -2,6 +2,7 @@ package com.cameleer3.server.app.config;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.io.ClassPathResource;
@@ -10,6 +11,9 @@ import org.springframework.jdbc.core.JdbcTemplate;
 import jakarta.annotation.PostConstruct;
 import javax.sql.DataSource;
 import java.nio.charset.StandardCharsets;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.Statement;
 
 /**
  * ClickHouse configuration.
@@ -25,6 +29,15 @@ public class ClickHouseConfig {
 
     private final DataSource dataSource;
 
+    @Value("${spring.datasource.url}")
+    private String datasourceUrl;
+
+    @Value("${spring.datasource.username}")
+    private String datasourceUsername;
+
+    @Value("${spring.datasource.password}")
+    private String datasourcePassword;
+
     public ClickHouseConfig(DataSource dataSource) {
         this.dataSource = dataSource;
     }
@@ -36,6 +49,7 @@ public class ClickHouseConfig {
 
     @PostConstruct
     void initSchema() {
+        ensureDatabaseExists();
         var jdbc = new JdbcTemplate(dataSource);
         for (String schemaFile : SCHEMA_FILES) {
             try {
@@ -53,4 +67,33 @@ public class ClickHouseConfig {
             }
         }
     }
+
+    /**
+     * Creates the ClickHouse database if it doesn't exist.
+     * Uses a separate connection without the database path, since the main
+     * DataSource connection fails if the database doesn't exist yet.
+     */
+    private void ensureDatabaseExists() {
+        // Extract database name from URL: jdbc:ch://host:port/dbname -> dbname
+        // Strip the database path to connect at root level
+        String rootUrl = datasourceUrl.replaceFirst("/[^/?]+($|\\?)", "$1");
+        String dbName = extractDatabaseName(datasourceUrl);
+
+        try (Connection conn = DriverManager.getConnection(rootUrl, datasourceUsername, datasourcePassword);
+             Statement stmt = conn.createStatement()) {
+            stmt.execute("CREATE DATABASE IF NOT EXISTS " + dbName);
+            log.info("Ensured database '{}' exists", dbName);
+        } catch (Exception e) {
+            log.error("Failed to ensure database exists", e);
+            throw new RuntimeException("Database creation failed", e);
+        }
+    }
+
+    static String extractDatabaseName(String jdbcUrl) {
+        // jdbc:ch://host:port/dbname or jdbc:ch://host:port/dbname?params
+        String afterScheme = jdbcUrl.substring(jdbcUrl.indexOf("://") + 3);
+        String afterHost = afterScheme.substring(afterScheme.indexOf('/') + 1);
+        int paramIdx = afterHost.indexOf('?');
+        return paramIdx >= 0 ? afterHost.substring(0, paramIdx) : afterHost;
+    }
 }