com.yahoo.vespa.config.server.application.ConfigInstanceBuilder Maven / Gradle / Ivy
// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
package com.yahoo.vespa.config.server.application;
import com.yahoo.config.ConfigBuilder;
import com.yahoo.config.ConfigInstance;
import com.yahoo.config.ConfigurationRuntimeException;
import com.yahoo.config.codegen.CNode;
import com.yahoo.config.codegen.InnerCNode;
import com.yahoo.config.codegen.LeafCNode;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.List;
import java.util.Map;
import java.util.logging.Level;
/**
* Builds a ConfigInstance from a ConfigInstance.Builder.
* (Put here not in ConfigInstance.Builder temporarily to work around dependency problems.)
*/
class ConfigInstanceBuilder {
private static final java.util.logging.Logger log = java.util.logging.Logger.getLogger(ConfigInstanceBuilder.class.getName());
static ConfigInstance buildInstance(ConfigInstance.Builder builder, InnerCNode targetDef) {
try {
if (targetDef != null) applyDef(builder, targetDef);
Class clazz = getConfigClass(builder.getClass());
return clazz.getConstructor(builder.getClass()).newInstance(builder);
} catch (Exception e) {
throw new ConfigurationRuntimeException(e);
}
}
/**
* If some fields on the builder are null now, set them from the def. Do recursively.
*
* If the targetDef has some schema incompatibilities, they are not handled here
* (except logging in some cases), but in ConfigInstance.serialize().
*
* @param builder a {@link com.yahoo.config.ConfigBuilder}
* @param targetDef a config definition
* @throws Exception if applying values form config definitions fails
*/
static void applyDef(ConfigBuilder builder, InnerCNode targetDef) throws Exception {
for (Map.Entry e: targetDef.children().entrySet()) {
CNode node = e.getValue();
if (node instanceof LeafCNode) {
setLeafValueIfUnset(targetDef, builder, (LeafCNode)node);
} else if (node instanceof InnerCNode) {
// Is there a private field on the builder that matches this inner node in the def?
if (hasField(builder.getClass(), node.getName())) {
Field innerField = builder.getClass().getDeclaredField(node.getName());
innerField.setAccessible(true);
Object innerFieldVal = innerField.get(builder);
if (innerFieldVal instanceof List innerList) {
// inner array? Check that list elems are ConfigBuilder
for (Object b : innerList) {
if (b instanceof ConfigBuilder) {
applyDef((ConfigBuilder) b, (InnerCNode) node);
}
}
} else if (innerFieldVal instanceof ConfigBuilder) {
// Struct perhaps
applyDef((ConfigBuilder) innerFieldVal, (InnerCNode) node);
} else {
// Likely a config value mismatch. That is handled in ConfigInstance.serialize() (error message, omit from response.)
}
}
}
}
}
private static boolean hasField(Class aClass, String name) {
for (Field field : aClass.getDeclaredFields()) {
if (name.equals(field.getName())) {
return true;
}
}
return false;
}
private static void setLeafValueIfUnset(InnerCNode targetDef, Object builder, LeafCNode node) throws Exception {
if (hasField(builder.getClass(), node.getName())) {
Field field = builder.getClass().getDeclaredField(node.getName());
field.setAccessible(true);
Object val = field.get(builder);
if (val==null) {
// Not set on builder, if the leaf node has a default value, try the private setter that takes String
try {
if (node.getDefaultValue()!=null) {
Method setter = builder.getClass().getDeclaredMethod(node.getName(), String.class);
setter.setAccessible(true);
setter.invoke(builder, node.getDefaultValue().getValue());
}
} catch (Exception e) {
log.log(Level.SEVERE,
"For config '" + targetDef.getFullName() + "': " +
"Unable to apply the default value for field '" + node.getName() +
"' to config Builder (where it wasn't set)",
e);
}
}
}
}
@SuppressWarnings("unchecked")
private static Class getConfigClass(Class builderClass) {
Class configClass = builderClass.getEnclosingClass();
if (configClass == null || ! ConfigInstance.class.isAssignableFrom(configClass)) {
throw new ConfigurationRuntimeException("Builder class " + builderClass + " has enclosing class " +
configClass + ", which is not a ConfigInstance");
}
return (Class) configClass;
}
}