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/*
* Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
* or more contributor license agreements. Licensed under the Elastic License
* 2.0 and the Server Side Public License, v 1; you may not use this file except
* in compliance with, at your election, the Elastic License 2.0 or the Server
* Side Public License, v 1.
*/
package org.elasticsearch.indices;
import org.apache.lucene.util.automaton.Automaton;
import org.apache.lucene.util.automaton.CharacterRunAutomaton;
import org.apache.lucene.util.automaton.Operations;
import org.apache.lucene.util.automaton.RegExp;
import org.elasticsearch.Version;
import org.elasticsearch.cluster.metadata.IndexMetadata;
import org.elasticsearch.cluster.metadata.Metadata;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.xcontent.XContentHelper;
import org.elasticsearch.threadpool.ThreadPool;
import org.elasticsearch.xcontent.XContentBuilder;
import org.elasticsearch.xcontent.XContentType;
import org.elasticsearch.xcontent.json.JsonXContent;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
/**
* A system index descriptor describes one or more system indices. It can match a number of indices using
* a pattern. For system indices that are managed externally to Elasticsearch, this is enough. For system
* indices that are managed internally to Elasticsearch, a descriptor can also include information for
* creating the system index, upgrading its mappings, and creating an alias.
*/
public class SystemIndexDescriptor implements IndexPatternMatcher, Comparable {
public static final Settings DEFAULT_SETTINGS = Settings.builder().put(IndexMetadata.SETTING_INDEX_HIDDEN, true).build();
/**
* A pattern, either with a wildcard or simple regex. Indices that match one of these patterns are considered system indices.
* Note that this pattern must not overlap with any other {@link SystemIndexDescriptor}s and must allow an alphanumeric suffix
* (see {@link SystemIndices#UPGRADED_INDEX_SUFFIX} for the specific suffix that's checked) to ensure that there's a name within the
* pattern we can use to create a new index when upgrading.
* */
private final String indexPattern;
/**
* For internally-managed indices, specifies the name of the concrete index to create and update. This is required
* since the {@link #indexPattern} can match many indices.
*/
private final String primaryIndex;
/** A description of the index or indices */
private final String description;
/** Used to determine whether an index name matches the {@link #indexPattern} */
private final CharacterRunAutomaton indexPatternAutomaton;
/** For internally-managed indices, contains the index mappings JSON */
private final String mappings;
/** For internally-managed indices, contains the index settings */
private final Settings settings;
/** For internally-managed indices, an optional alias to create */
private final String aliasName;
/** For internally-managed indices, an optional {@link IndexMetadata#INDEX_FORMAT_SETTING} value to expect */
private final int indexFormat;
/**
* For internally-managed indices, specifies a key name under _meta in the index mappings
* that contains the index's mappings' version.
*/
private final String versionMetaKey;
/** For internally-managed indices, specifies the origin to use when creating or updating the index */
private final String origin;
/** The minimum cluster node version required for this descriptor */
private final Version minimumNodeVersion;
/** Mapping version from the descriptor */
private final Version mappingVersion;
/** Whether there are dynamic fields in this descriptor's mappings */
private final boolean hasDynamicMappings;
/** The {@link Type} of system index this descriptor represents */
private final Type type;
/** A list of allowed product origins that may access an external system index */
private final List allowedElasticProductOrigins;
/**
* A list of prior system index descriptors that can be used when one or more data/master nodes is on a version lower than the
* minimum supported version for this descriptor
*/
private final List priorSystemIndexDescriptors;
private final boolean isNetNew;
/**
* The thread pools that actions will use to operate on this descriptor's system indices
*/
private final ExecutorNames executorNames;
/**
* Creates a descriptor for system indices matching the supplied pattern. These indices will not be managed
* by Elasticsearch internally.
* @param indexPattern The pattern of index names that this descriptor will be used for. Must start with a '.' character, must not
* overlap with any other descriptor patterns, and must allow a suffix (see note on
* {@link SystemIndexDescriptor#indexPattern} for details).
* @param description The name of the plugin responsible for this system index.
*/
public SystemIndexDescriptor(String indexPattern, String description) {
this(
indexPattern,
null,
description,
null,
null,
null,
0,
null,
null,
Version.CURRENT.minimumCompatibilityVersion(),
Type.INTERNAL_UNMANAGED,
List.of(),
List.of(),
null,
false
);
}
/**
* Creates a descriptor for system indices matching the supplied pattern. These indices will not be managed
* by Elasticsearch internally.
* @param indexPattern The pattern of index names that this descriptor will be used for. Must start with a '.' character, must not
* overlap with any other descriptor patterns, and must allow a suffix (see note on
* {@link SystemIndexDescriptor#indexPattern} for details).
* @param description The name of the plugin responsible for this system index.
* @param type The {@link Type} of system index
* @param allowedElasticProductOrigins A list of allowed origin values that should be allowed access in the case of external system
* indices
*/
public SystemIndexDescriptor(String indexPattern, String description, Type type, List allowedElasticProductOrigins) {
this(
indexPattern,
null,
description,
null,
null,
null,
0,
null,
null,
Version.CURRENT.minimumCompatibilityVersion(),
type,
allowedElasticProductOrigins,
List.of(),
null,
false
);
}
/**
* Creates a descriptor for system indices matching the supplied pattern. These indices will be managed
* by Elasticsearch internally if mappings or settings are provided.
*
* @param indexPattern The pattern of index names that this descriptor will be used for. Must start with a '.' character, must not
* overlap with any other descriptor patterns, and must allow a suffix (see note on
* {@link SystemIndexDescriptor#indexPattern} for details).
* @param primaryIndex The primary index name of this descriptor. Used when creating the system index for the first time.
* @param description The name of the plugin responsible for this system index.
* @param mappings The mappings to apply to this index when auto-creating, if appropriate
* @param settings The settings to apply to this index when auto-creating, if appropriate
* @param aliasName An alias for the index, or null
* @param indexFormat A value for the `index.format` setting. Pass 0 or higher.
* @param versionMetaKey a mapping key under _meta where a version can be found, which indicates the
* Elasticsearch version when the index was created.
* @param origin the client origin to use when creating this index.
* @param minimumNodeVersion the minimum cluster node version required for this descriptor
* @param type The {@link Type} of system index
* @param allowedElasticProductOrigins A list of allowed origin values that should be allowed access in the case of external system
* indices
* @param priorSystemIndexDescriptors A list of system index descriptors that describe the same index in a way that is compatible with
* older versions of Elasticsearch
*/
SystemIndexDescriptor(
String indexPattern,
String primaryIndex,
String description,
String mappings,
Settings settings,
String aliasName,
int indexFormat,
String versionMetaKey,
String origin,
Version minimumNodeVersion,
Type type,
List allowedElasticProductOrigins,
List priorSystemIndexDescriptors,
ExecutorNames executorNames,
boolean isNetNew
) {
Objects.requireNonNull(indexPattern, "system index pattern must not be null");
if (indexPattern.length() < 2) {
throw new IllegalArgumentException(
"system index pattern provided as [" + indexPattern + "] but must at least 2 characters in length"
);
}
if (indexPattern.charAt(0) != '.') {
throw new IllegalArgumentException(
"system index pattern provided as [" + indexPattern + "] but must start with the character [.]"
);
}
if (indexPattern.charAt(1) == '*') {
throw new IllegalArgumentException(
"system index pattern provided as ["
+ indexPattern
+ "] but must not start with the character sequence [.*] to prevent conflicts"
);
}
if (primaryIndex != null) {
if (primaryIndex.charAt(0) != '.') {
throw new IllegalArgumentException(
"system primary index provided as [" + primaryIndex + "] but must start with the character [.]"
);
}
if (primaryIndex.matches("^\\.[\\w-]+$") == false) {
throw new IllegalArgumentException(
"system primary index provided as [" + primaryIndex + "] but cannot contain special characters or patterns"
);
}
}
if (indexFormat < 0) {
throw new IllegalArgumentException("Index format cannot be negative");
}
Strings.requireNonEmpty(indexPattern, "indexPattern must be supplied");
Objects.requireNonNull(type, "type must not be null");
if (type.isManaged()) {
Objects.requireNonNull(settings, "Must supply settings for a managed system index");
Strings.requireNonEmpty(mappings, "Must supply mappings for a managed system index");
Strings.requireNonEmpty(primaryIndex, "Must supply primaryIndex for a managed system index");
Strings.requireNonEmpty(versionMetaKey, "Must supply versionMetaKey for a managed system index");
Strings.requireNonEmpty(origin, "Must supply origin for a managed system index");
if (settings.getAsInt(IndexMetadata.INDEX_FORMAT_SETTING.getKey(), 0) != indexFormat) {
throw new IllegalArgumentException("Descriptor index format does not match index format in managed settings");
}
this.mappingVersion = extractVersionFromMappings(mappings, versionMetaKey);
} else {
this.mappingVersion = null;
}
Objects.requireNonNull(allowedElasticProductOrigins, "allowedProductOrigins must not be null");
if (type.isInternal() && allowedElasticProductOrigins.isEmpty() == false) {
throw new IllegalArgumentException("Allowed origins are not valid for internal system indices");
} else if (type.isExternal() && allowedElasticProductOrigins.isEmpty()) {
throw new IllegalArgumentException("External system indices without allowed products is not a valid combination");
}
Objects.requireNonNull(minimumNodeVersion, "minimumNodeVersion must be provided!");
Objects.requireNonNull(priorSystemIndexDescriptors, "priorSystemIndexDescriptors must not be null");
if (priorSystemIndexDescriptors.isEmpty() == false) {
// the rules for prior system index descriptors
// 1. No values with the same minimum node version
// 2. All prior system index descriptors must have a minimumNodeVersion before this one
// 3. Prior system index descriptors may not have other prior system index descriptors
// to avoid multiple branches that need followed
// 4. Must have same indexPattern, primaryIndex, and alias
Set versions = new HashSet<>(priorSystemIndexDescriptors.size() + 1);
versions.add(minimumNodeVersion);
for (SystemIndexDescriptor prior : priorSystemIndexDescriptors) {
if (versions.add(prior.minimumNodeVersion) == false) {
throw new IllegalArgumentException(prior + " has the same minimum node version as another descriptor");
}
if (prior.minimumNodeVersion.after(minimumNodeVersion)) {
throw new IllegalArgumentException(
prior + " has minimum node version [" + prior.minimumNodeVersion + "] which is after [" + minimumNodeVersion + "]"
);
}
if (prior.priorSystemIndexDescriptors.isEmpty() == false) {
throw new IllegalArgumentException(prior + " has its own prior descriptors but only a depth of 1 is allowed");
}
if (prior.indexPattern.equals(indexPattern) == false) {
throw new IllegalArgumentException("index pattern must be the same");
}
if (prior.primaryIndex.equals(primaryIndex) == false) {
throw new IllegalArgumentException("primary index must be the same");
}
if (prior.aliasName.equals(aliasName) == false) {
throw new IllegalArgumentException("alias name must be the same");
}
}
}
if (Objects.nonNull(executorNames)) {
if (ThreadPool.THREAD_POOL_TYPES.containsKey(executorNames.threadPoolForGet()) == false) {
throw new IllegalArgumentException(executorNames.threadPoolForGet() + " is not a valid thread pool");
}
if (ThreadPool.THREAD_POOL_TYPES.containsKey(executorNames.threadPoolForSearch()) == false) {
throw new IllegalArgumentException(executorNames.threadPoolForGet() + " is not a valid thread pool");
}
if (ThreadPool.THREAD_POOL_TYPES.containsKey(executorNames.threadPoolForWrite()) == false) {
throw new IllegalArgumentException(executorNames.threadPoolForGet() + " is not a valid thread pool");
}
}
this.indexPattern = indexPattern;
this.primaryIndex = primaryIndex;
this.aliasName = aliasName;
final Automaton automaton = buildAutomaton(indexPattern, aliasName);
this.indexPatternAutomaton = new CharacterRunAutomaton(automaton);
if (primaryIndex != null && indexPatternAutomaton.run(primaryIndex) == false) {
throw new IllegalArgumentException("primary index does not match the index pattern!");
}
this.description = description;
this.mappings = mappings;
settings = Objects.isNull(settings) ? Settings.EMPTY : settings;
if (settings.hasValue(IndexMetadata.SETTING_INDEX_HIDDEN) == false) {
settings = Settings.builder().put(settings).put(DEFAULT_SETTINGS).build();
}
if (settings.getAsBoolean(IndexMetadata.SETTING_INDEX_HIDDEN, false)) {
this.settings = settings;
} else {
throw new IllegalArgumentException("System indices must have " + IndexMetadata.SETTING_INDEX_HIDDEN + " set to true.");
}
this.indexFormat = indexFormat;
this.versionMetaKey = versionMetaKey;
this.origin = origin;
this.minimumNodeVersion = minimumNodeVersion;
this.type = type;
this.allowedElasticProductOrigins = allowedElasticProductOrigins;
this.hasDynamicMappings = this.mappings != null
&& findDynamicMapping(XContentHelper.convertToMap(JsonXContent.jsonXContent, mappings, false));
final List sortedPriorSystemIndexDescriptors;
if (priorSystemIndexDescriptors.isEmpty() || priorSystemIndexDescriptors.size() == 1) {
sortedPriorSystemIndexDescriptors = List.copyOf(priorSystemIndexDescriptors);
} else {
List copy = new ArrayList<>(priorSystemIndexDescriptors);
Collections.sort(copy);
sortedPriorSystemIndexDescriptors = List.copyOf(copy);
}
this.priorSystemIndexDescriptors = sortedPriorSystemIndexDescriptors;
this.executorNames = Objects.nonNull(executorNames) ? executorNames : ExecutorNames.DEFAULT_SYSTEM_INDEX_THREAD_POOLS;
this.isNetNew = isNetNew;
}
/**
* @return The pattern of index names that this descriptor will be used for. Must start with a '.' character, must not
* overlap with any other descriptor patterns, and must allow a suffix (see note on
* {@link SystemIndexDescriptor#indexPattern} for details).
*/
@Override
public String getIndexPattern() {
return indexPattern;
}
/**
* @return The concrete name of an index being managed internally to Elasticsearch. Will be {@code null}
* for indices managed externally to Elasticsearch.
*/
public String getPrimaryIndex() {
return primaryIndex;
}
/**
* Checks whether an index name matches the system index name pattern for this descriptor.
* @param index The index name to be checked against the index pattern given at construction time.
* @return True if the name matches the pattern, false otherwise.
*/
public boolean matchesIndexPattern(String index) {
return indexPatternAutomaton.run(index);
}
/**
* Retrieves a list of all indices which match this descriptor's pattern.
*
* This cannot be done via {@link org.elasticsearch.cluster.metadata.IndexNameExpressionResolver} because that class can only handle
* simple wildcard expressions, but system index name patterns may use full Lucene regular expression syntax,
*
* @param metadata The current metadata to get the list of matching indices from
* @return A list of index names that match this descriptor
*/
@Override
public List getMatchingIndices(Metadata metadata) {
return metadata.indices().keySet().stream().filter(this::matchesIndexPattern).toList();
}
/**
* @return A short description of the purpose of this system index.
*/
public String getDescription() {
return description;
}
@Override
public String toString() {
return "SystemIndexDescriptor[pattern=[" + indexPattern + "], description=[" + description + "], aliasName=[" + aliasName + "]]";
}
public String getMappings() {
return mappings;
}
public Settings getSettings() {
return settings;
}
public String getAliasName() {
return aliasName;
}
public int getIndexFormat() {
return this.indexFormat;
}
public String getVersionMetaKey() {
return this.versionMetaKey;
}
public Version getMinimumNodeVersion() {
return minimumNodeVersion;
}
public boolean isAutomaticallyManaged() {
return type.isManaged();
}
public String getOrigin() {
return this.origin;
}
public boolean hasDynamicMappings() {
return this.hasDynamicMappings;
}
public boolean isExternal() {
return type.isExternal();
}
public boolean isInternal() {
return type.isInternal();
}
public List getAllowedElasticProductOrigins() {
return allowedElasticProductOrigins;
}
public boolean isNetNew() {
return isNetNew;
}
public Version getMappingVersion() {
if (type.isManaged() == false) {
throw new IllegalStateException(this + " is not managed so there are no mappings or version");
}
return mappingVersion;
}
/**
* Gets a standardized message when the node contains a data or master node whose version is less
* than that of the minimum supported version of this descriptor and its prior descriptors.
*
* @param cause the action being attempted that triggered the check. Used in the error message.
* @return the standardized error message
*/
public String getMinimumNodeVersionMessage(String cause) {
Objects.requireNonNull(cause);
final Version actualMinimumVersion = priorSystemIndexDescriptors.isEmpty()
? minimumNodeVersion
: priorSystemIndexDescriptors.get(priorSystemIndexDescriptors.size() - 1).minimumNodeVersion;
return String.format(
Locale.ROOT,
"[%s] failed - system index [%s] requires all data and master nodes to be at least version [%s]",
cause,
this.getPrimaryIndex(),
actualMinimumVersion
);
}
/**
* Finds the descriptor that can be used within this cluster, by comparing the supplied minimum
* node version to this descriptor's minimum version and the prior descriptors minimum version.
*
* @param version the lower node version in the cluster
* @return null if the lowest node version is lower than the minimum version in this descriptor,
* or the appropriate descriptor if the supplied version is acceptable.
*/
public SystemIndexDescriptor getDescriptorCompatibleWith(Version version) {
if (minimumNodeVersion.onOrBefore(version)) {
return this;
}
for (SystemIndexDescriptor prior : priorSystemIndexDescriptors) {
if (version.onOrAfter(prior.minimumNodeVersion)) {
return prior;
}
}
return null;
}
/**
* @return The names of thread pools that should be used for operations on this
* system index.
*/
public ExecutorNames getThreadPoolNames() {
return this.executorNames;
}
public static Builder builder() {
return new Builder();
}
@Override
public int compareTo(SystemIndexDescriptor other) {
return minimumNodeVersion.compareTo(other.minimumNodeVersion) * -1;
}
/**
* The specific type of system index that this descriptor represents. System indices can be one of four defined types; the type is used
* to control behavior. Elasticsearch itself and plugins have system indices that are necessary for their features;
* these system indices are referred to as internal system indices. System indices can also belong to features outside of Elasticsearch
* that may be part of other Elastic stack components. These are external system indices as the intent is for these to be accessed via
* normal APIs with a special value.
*
* Within both internal and external system indices, there are two sub-types. The first are those that are managed by Elasticsearch and
* will have mappings/settings changed as the cluster itself is upgraded. The second are those managed by the owning applications code
* and for those Elasticsearch will not perform any updates.
*
* Internal system indices are almost always managed indices that Elasticsearch manages, but there are cases where the component of
* Elasticsearch will need to manage the system indices itself.
*/
public enum Type {
INTERNAL_MANAGED(false, true),
INTERNAL_UNMANAGED(false, false),
EXTERNAL_MANAGED(true, true),
EXTERNAL_UNMANAGED(true, false);
private final boolean external;
private final boolean managed;
Type(boolean external, boolean managed) {
this.external = external;
this.managed = managed;
}
public boolean isExternal() {
return external;
}
public boolean isManaged() {
return managed;
}
public boolean isInternal() {
return external == false;
}
}
/**
* Provides a fluent API for building a {@link SystemIndexDescriptor}. Validation still happens in that class.
*/
public static class Builder {
private String indexPattern;
private String primaryIndex;
private String description;
private String mappings = null;
private Settings settings = null;
private String aliasName = null;
private int indexFormat = 0;
private String versionMetaKey = null;
private String origin = null;
private Version minimumNodeVersion = Version.CURRENT.minimumCompatibilityVersion();
private Type type = Type.INTERNAL_MANAGED;
private List allowedElasticProductOrigins = List.of();
private List priorSystemIndexDescriptors = List.of();
private ExecutorNames executorNames;
private boolean isNetNew = false;
private Builder() {}
public Builder setIndexPattern(String indexPattern) {
this.indexPattern = indexPattern;
return this;
}
public Builder setPrimaryIndex(String primaryIndex) {
this.primaryIndex = primaryIndex;
return this;
}
public Builder setDescription(String description) {
this.description = description;
return this;
}
public Builder setMappings(XContentBuilder mappingsBuilder) {
mappings = mappingsBuilder == null ? null : Strings.toString(mappingsBuilder);
return this;
}
public Builder setMappings(String mappings) {
this.mappings = mappings;
return this;
}
public Builder setSettings(Settings settings) {
this.settings = settings;
return this;
}
public Builder setAliasName(String aliasName) {
this.aliasName = aliasName;
return this;
}
public Builder setIndexFormat(int indexFormat) {
this.indexFormat = indexFormat;
return this;
}
public Builder setVersionMetaKey(String versionMetaKey) {
this.versionMetaKey = versionMetaKey;
return this;
}
public Builder setOrigin(String origin) {
this.origin = origin;
return this;
}
public Builder setMinimumNodeVersion(Version version) {
this.minimumNodeVersion = version;
return this;
}
public Builder setType(Type type) {
this.type = type;
return this;
}
public Builder setAllowedElasticProductOrigins(List allowedElasticProductOrigins) {
this.allowedElasticProductOrigins = allowedElasticProductOrigins;
return this;
}
public Builder setPriorSystemIndexDescriptors(List priorSystemIndexDescriptors) {
this.priorSystemIndexDescriptors = priorSystemIndexDescriptors;
return this;
}
public Builder setThreadPools(ExecutorNames threadPoolExecutorNames) {
this.executorNames = threadPoolExecutorNames;
return this;
}
public Builder setNetNew() {
this.isNetNew = true;
return this;
}
/**
* Builds a {@link SystemIndexDescriptor} using the fields supplied to this builder.
* @return a populated descriptor.
*/
public SystemIndexDescriptor build() {
return new SystemIndexDescriptor(
indexPattern,
primaryIndex,
description,
mappings,
settings,
aliasName,
indexFormat,
versionMetaKey,
origin,
minimumNodeVersion,
type,
allowedElasticProductOrigins,
priorSystemIndexDescriptors,
executorNames,
isNetNew
);
}
}
/**
* Builds an automaton for matching index names against this descriptor's index pattern.
* If this descriptor has an alias name, the automaton will also try to match against
* the alias as well.
*/
static Automaton buildAutomaton(String pattern, String alias) {
final String patternAsRegex = patternToRegex(pattern);
final String aliasAsRegex = alias == null ? null : patternToRegex(alias);
final Automaton patternAutomaton = new RegExp(patternAsRegex).toAutomaton();
if (aliasAsRegex == null) {
return patternAutomaton;
}
final Automaton aliasAutomaton = new RegExp(aliasAsRegex).toAutomaton();
return Operations.union(patternAutomaton, aliasAutomaton);
}
/**
* Translate a simple string pattern into a regular expression, suitable for creating a
* {@link RegExp} instance. This exists because although
* {@link org.elasticsearch.common.regex.Regex#simpleMatchToAutomaton(String)} is useful
* for simple patterns, it doesn't support character ranges.
*
* @param input the string to translate
* @return the translate string
*/
private static String patternToRegex(String input) {
String output = input;
output = output.replaceAll("\\.", "\\\\.");
output = output.replaceAll("\\*", ".*");
return output;
}
/**
* Recursively searches for dynamic: true in the supplies mappings
* @param map a parsed fragment of an index's mappings
* @return whether the fragment contains a dynamic mapping
*/
@SuppressWarnings("unchecked")
static boolean findDynamicMapping(Map map) {
if (map == null) {
return false;
}
for (Map.Entry entry : map.entrySet()) {
final String key = entry.getKey();
final Object value = entry.getValue();
if (key.equals("dynamic") && (value instanceof Boolean) && ((Boolean) value)) {
return true;
}
if (value instanceof Map) {
if (findDynamicMapping((Map) value)) {
return true;
}
}
}
return false;
}
@SuppressWarnings("unchecked")
private static Version extractVersionFromMappings(String mappings, String versionMetaKey) {
final Map mappingsMap = XContentHelper.convertToMap(XContentType.JSON.xContent(), mappings, false);
final Map doc = (Map) mappingsMap.get("_doc");
final Map meta;
if (doc == null) {
meta = (Map) mappingsMap.get("_meta");
} else {
meta = (Map) doc.get("_meta");
}
if (meta == null) {
throw new IllegalStateException("mappings do not have _meta field");
}
final String value = (String) meta.get(versionMetaKey);
if (value == null) {
throw new IllegalArgumentException("mappings do not have a version in _meta." + versionMetaKey);
}
return Version.fromString(value);
}
}