| // Copyright (C) 2015 The Android Open Source Project |
| // |
| // 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 com.google.gerrit.metrics; |
| |
| import static com.google.common.base.Preconditions.checkArgument; |
| |
| import com.google.auto.value.AutoValue; |
| import com.google.gerrit.server.logging.Metadata; |
| import java.util.Optional; |
| import java.util.function.BiConsumer; |
| import java.util.function.Function; |
| |
| /** |
| * Describes a bucketing field used by a metric. |
| * |
| * @param <T> type of field |
| */ |
| @AutoValue |
| public abstract class Field<T> { |
| public static <T> BiConsumer<Metadata.Builder, T> ignoreMetadata() { |
| return (metadataBuilder, fieldValue) -> {}; |
| } |
| |
| /** |
| * Break down metrics by boolean true/false. |
| * |
| * @param name field name |
| * @return builder for the boolean field |
| */ |
| public static Field.Builder<Boolean> ofBoolean( |
| String name, BiConsumer<Metadata.Builder, Boolean> metadataMapper) { |
| return new AutoValue_Field.Builder<Boolean>() |
| .valueType(Boolean.class) |
| .formatter(Object::toString) |
| .name(name) |
| .metadataMapper(metadataMapper); |
| } |
| |
| /** |
| * Break down metrics by cases of an enum. |
| * |
| * @param enumType type of enum |
| * @param name field name |
| * @return builder for the enum field |
| */ |
| public static <E extends Enum<E>> Field.Builder<E> ofEnum( |
| Class<E> enumType, String name, BiConsumer<Metadata.Builder, String> metadataMapper) { |
| return new AutoValue_Field.Builder<E>() |
| .valueType(enumType) |
| .formatter(Enum::name) |
| .name(name) |
| .metadataMapper( |
| (metadataBuilder, fieldValue) -> |
| metadataMapper.accept(metadataBuilder, fieldValue.name())); |
| } |
| |
| /** |
| * Break down metrics by integer. |
| * |
| * <p>Each unique integer will allocate a new submetric. <b>Do not use user content as a field |
| * value</b> as field values are never reclaimed. |
| * |
| * @param name field name |
| * @return builder for the integer field |
| */ |
| public static Field.Builder<Integer> ofInteger( |
| String name, BiConsumer<Metadata.Builder, Integer> metadataMapper) { |
| return new AutoValue_Field.Builder<Integer>() |
| .valueType(Integer.class) |
| .formatter(Object::toString) |
| .name(name) |
| .metadataMapper(metadataMapper); |
| } |
| |
| /** |
| * Break down metrics by string. |
| * |
| * <p>Each unique string will allocate a new submetric. <b>Do not use user content as a field |
| * value</b> as field values are never reclaimed. |
| * |
| * @param name field name |
| * @return builder for the string field |
| */ |
| public static Field.Builder<String> ofString( |
| String name, BiConsumer<Metadata.Builder, String> metadataMapper) { |
| return new AutoValue_Field.Builder<String>() |
| .valueType(String.class) |
| .formatter(s -> s) |
| .name(name) |
| .metadataMapper(metadataMapper); |
| } |
| |
| /** @return name of this field within the metric. */ |
| public abstract String name(); |
| |
| /** @return type of value used within the field. */ |
| public abstract Class<T> valueType(); |
| |
| /** @return mapper that maps a field value to a field in the {@link Metadata} class. */ |
| public abstract BiConsumer<Metadata.Builder, T> metadataMapper(); |
| |
| /** @return description text for the field explaining its range of values. */ |
| public abstract Optional<String> description(); |
| |
| /** @return formatter to format field values. */ |
| public abstract Function<T, String> formatter(); |
| |
| @AutoValue.Builder |
| public abstract static class Builder<T> { |
| abstract Builder<T> name(String name); |
| |
| abstract Builder<T> valueType(Class<T> type); |
| |
| abstract Builder<T> formatter(Function<T, String> formatter); |
| |
| abstract Builder<T> metadataMapper(BiConsumer<Metadata.Builder, T> metadataMapper); |
| |
| public abstract Builder<T> description(String description); |
| |
| abstract Field<T> autoBuild(); |
| |
| public Field<T> build() { |
| Field<T> field = autoBuild(); |
| checkArgument(field.name().matches("^[a-z_]+$"), "name must match [a-z_]"); |
| return field; |
| } |
| } |
| } |