io.rxmicro.config.Config Maven / Gradle / Ivy
/*
* Copyright (c) 2020. https://rxmicro.io
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.rxmicro.config;
import java.util.List;
import static io.rxmicro.common.util.Strings.splitByCamelCase;
import static java.util.stream.Collectors.joining;
/**
* The parent class for all config classes.
*
* @author nedis
* @see ConfigSource
* @since 0.1
*/
public abstract class Config {
/**
* Defines a character that used as list (set, sorted set, map entries) values delimiter.
*
*
* Collection examples:
*
* propertyName1=value1,value2,value3
*
* For such cases {@code propertyName1} can be converted to {@link List}{@code }
* (or {@link java.util.Set}{@code } or {@link java.util.SortedSet}{@code } if possible) instance automatically.
*
*
* Map examples:
*
* propertyName2=key1=value1,key2=value2,key3=value3
*
* For such cases {@code propertyName2} can be converted to {@link java.util.Map}{@code } instance automatically.
*/
public static final Character VALUES_DELIMITER = ',';
/**
* Defines a character that used as key-value map entry delimiter.
*
*
* For example:
*
* propertyName=key1=value1,key2=value2,key3=value3
*
* For such cases {@code propertyName} can be converted to {@link java.util.Map}{@code } instance automatically.
*/
public static final Character KEY_VALUE_ENTRY_DELIMITER = '=';
/**
* Default name for config file or class path resource without extension.
*
*
* This name used by {@link ConfigSource#RXMICRO_CLASS_PATH_RESOURCE} or
* {@link ConfigSource#RXMICRO_FILE_AT_THE_HOME_DIR} or
* {@link ConfigSource#RXMICRO_FILE_AT_THE_RXMICRO_CONFIG_DIR} or
* {@link ConfigSource#RXMICRO_FILE_AT_THE_CURRENT_DIR}.
*/
public static final String RX_MICRO_CONFIG_FILE_NAME = "rxmicro";
/**
* Allows defining the prefix name that will be used for all environment variable source for configs.
*
*
* The RxMicro framework allows using the environment variables for configuring the config instances.
* By default the ${namespace}.${propertyName}=${propertyValue} format is used.
*
*
* But some tools add the additional restrictions for environment variables:
*
*
* Environment variable names used by the utilities in the Shell and Utilities volume of IEEE Std 1003.1-2001 consist solely of
* uppercase letters, digits, and the '_' (underscore) from the characters defined in Portable Character Set and do not begin with
* a digit. Other characters may be permitted by an implementation; applications shall tolerate the presence of such names.
*
*
* So the RxMicro framework must support both:
*
* - {@code export TEST_CONFIG_CLASS_PROPERTY_NAME=value}
* - {@code export test-config-class.propertyName=value}
*
* environment variable names for the {@code propertyName} that defined at the {@code TestConfigClassConfig} class.
*
*
* If {@value #RX_MICRO_CONFIG_ENVIRONMENT_VARIABLE_PREFIX} is defined the RxMicro framework will expect the following
* environment variable name for the {@code propertyName} that defined at the {@code TestConfigClassConfig} class:
* {@code export ${RX_MICRO_CONFIG_ENVIRONMENT_VARIABLE_PREFIX}_TEST_CONFIG_CLASS_PROPERTY_NAME=value}
*/
public static final String RX_MICRO_CONFIG_ENVIRONMENT_VARIABLE_PREFIX = "RX_MICRO_CONFIG_ENVIRONMENT_VARIABLE_PREFIX";
/**
* Default name for config directory.
*
*
* This name used by {@link ConfigSource#SEPARATE_FILE_AT_THE_RXMICRO_CONFIG_DIR} or
* {@link ConfigSource#RXMICRO_FILE_AT_THE_RXMICRO_CONFIG_DIR}.
*/
public static final String RX_MICRO_CONFIG_DIRECTORY_NAME = ".rxmicro";
private static final String AS_MAP_CONFIG_NAME = AsMapConfig.class.getSimpleName();
private static final String CONFIG_NAME = Config.class.getSimpleName();
/**
* Defines the default namespace for the config class.
*
* @param configClass the config class
* @return the default namespace
*/
public static String getDefaultNameSpace(final Class configClass) {
return getDefaultNameSpace(configClass.getSimpleName());
}
/**
* Defines the default namespace for config simple class name (without package).
*
* @param configSimpleClassName the config simple class name
* @return the default namespace
*/
public static String getDefaultNameSpace(final String configSimpleClassName) {
final List words = splitByCamelCase(getValidConfigSimpleClassName(configSimpleClassName));
return words.stream()
.map(String::toLowerCase)
.collect(joining("-"));
}
private static String getValidConfigSimpleClassName(final String name) {
if (name.endsWith(AS_MAP_CONFIG_NAME)) {
return name.substring(0, name.length() - AS_MAP_CONFIG_NAME.length());
} else if (name.endsWith(CONFIG_NAME)) {
return name.substring(0, name.length() - CONFIG_NAME.length());
} else {
return name;
}
}
/**
* Returns the default namespace for config instance.
*
* @return the default namespace for config instance
*/
public String getNameSpace() {
return getDefaultNameSpace(getClass());
}
/**
* Validates the config instance state after injection all properties.
*
*
* By default this implementation joins exceptions returned by {@link #getAllFoundConfigExceptions(String)} method and
* throws a single {@link ConfigException} instance with joined messages and suppressed stacktraces.
*
*
* Note: If it is necessary to interrupt the launching of microservice as soon as possible,
* You must override {@link #validate(String)} method instead of {@link #getAllFoundConfigExceptions(String)} one!
*
*
* Note: If it is necessary to view all detected config errors per config instance,
* You must override {@link #getAllFoundConfigExceptions(String)} method instead of {@link #validate(String)} one!
*
* @param namespace the config namespace
* @throws ConfigException if current config instance has invalid state
* @see #getAllFoundConfigExceptions(String)
*/
protected void validate(final String namespace) {
final List exceptions = getAllFoundConfigExceptions(namespace);
if (!exceptions.isEmpty()) {
final ConfigException exception = new ConfigException(
"'?' config contains the following validation errors:\n?",
namespace, exceptions.stream().map(Throwable::getMessage).collect(joining("\n"))
);
exceptions.forEach(exception::addSuppressed);
throw exception;
}
}
/**
* Returns the exception list that must be joined to the single {@link ConfigException} instance.
*
* @param namespace the config namespace
* @return the exception list that must be joined to the single {@link ConfigException} instance.
* @see #validate(String)
*/
protected List getAllFoundConfigExceptions(final String namespace) {
return List.of();
}
}