package <%=packageName%>.config.metrics;
import org.springframework.boot.actuate.health.AbstractHealthIndicator;
import org.springframework.boot.actuate.health.Health;<% if (databaseType == 'sql') { %><% if (javaVersion == '7') { %>
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.core.ConnectionCallback;<% } %>
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.util.StringUtils;
import javax.sql.DataSource;
import java.sql.Connection;<% if (javaVersion == '7') { %>
import java.sql.SQLException;<% } %>
import java.util.HashMap;
import java.util.Map;<% } %>
/**
* SpringBoot Actuator HealthIndicator check for the Database.
*/
public class DatabaseHealthIndicator extends AbstractHealthIndicator {
<% if (databaseType == 'sql') { %>
private DataSource dataSource;
private JdbcTemplate jdbcTemplate;
private static Map<String, String> queries = new HashMap<>();
static {
queries.put("HSQL Database Engine",
"SELECT COUNT(*) FROM INFORMATION_SCHEMA.SYSTEM_USERS");
queries.put("Oracle", "SELECT 'Hello' from DUAL");
queries.put("Apache Derby", "SELECT 1 FROM SYSIBM.SYSDUMMY1");
queries.put("MySQL", "SELECT 1");
queries.put("PostgreSQL", "SELECT 1");
queries.put("Microsoft SQL Server", "SELECT 1");
}
private static String DEFAULT_QUERY = "SELECT 1";
private String query = null;
public DatabaseHealthIndicator(DataSource dataSource) {
this.dataSource = dataSource;
this.jdbcTemplate = new JdbcTemplate(dataSource);
}
@Override
protected void doHealthCheck(Health.Builder builder) throws Exception {
String product = getProduct();
builder.up().withDetail("database", product);
String query = detectQuery(product);
if (StringUtils.hasText(query)) {
try {
builder.withDetail("hello",
this.jdbcTemplate.queryForObject(query, Object.class));
} catch (Exception ex) {
builder.down(ex);
}
}
}
private String getProduct() {
return this.jdbcTemplate.execute(<% if (javaVersion == '8') { %>(Connection connection) -> connection.getMetaData().getDatabaseProductName()<% } else { %>new ConnectionCallback<String>() {
@Override
public String doInConnection(Connection connection) throws SQLException,
DataAccessException {
return connection.getMetaData().getDatabaseProductName();
}
}<% } %>);
}
protected String detectQuery(String product) {
String query = this.query;
if (!StringUtils.hasText(query)) {
query = queries.get(product);
}
if (!StringUtils.hasText(query)) {
query = DEFAULT_QUERY;
}
return query;
}
public void setQuery(String query) {
this.query = query;
}<% } else { %>
@Override
protected void doHealthCheck(Health.Builder builder) throws Exception {
// do nothing
}<% } %>
}