org.neo4j.driver.SessionConfig Maven / Gradle / Ivy
/*
* Copyright (c) "Neo4j"
* Neo4j Sweden AB [http://neo4j.com]
*
* This file is part of Neo4j.
*
* 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 org.neo4j.driver;
import static java.util.Objects.requireNonNull;
import static org.neo4j.driver.internal.handlers.pulln.FetchSizeUtil.assertValidFetchSize;
import java.io.Serial;
import java.io.Serializable;
import java.util.Arrays;
import java.util.Objects;
import java.util.Optional;
import org.neo4j.driver.async.AsyncSession;
import org.neo4j.driver.reactive.ReactiveSession;
import org.neo4j.driver.reactive.RxSession;
import org.neo4j.driver.util.Experimental;
import org.reactivestreams.Subscription;
/**
* The session configurations used to configure a session.
*/
public final class SessionConfig implements Serializable {
@Serial
private static final long serialVersionUID = 5773462156979050657L;
private static final SessionConfig EMPTY = builder().build();
private final Iterable bookmarks;
private final AccessMode defaultAccessMode;
private final String database;
private final Long fetchSize;
private final String impersonatedUser;
private final BookmarkManager bookmarkManager;
private SessionConfig(Builder builder) {
this.bookmarks = builder.bookmarks;
this.defaultAccessMode = builder.defaultAccessMode;
this.database = builder.database;
this.fetchSize = builder.fetchSize;
this.impersonatedUser = builder.impersonatedUser;
this.bookmarkManager = builder.bookmarkManager;
}
/**
* Creates a new {@link Builder} used to construct a configuration object.
*
* @return a session configuration builder.
*/
public static Builder builder() {
return new Builder();
}
/**
* Returns a static {@link SessionConfig} with default values for a general purpose session.
*
* @return a session config for a general purpose session.
*/
public static SessionConfig defaultConfig() {
return EMPTY;
}
/**
* Returns a {@link SessionConfig} for the specified database
* @param database the database the session binds to.
* @return a session config for a session for the specified database.
*/
public static SessionConfig forDatabase(String database) {
return new Builder().withDatabase(database).build();
}
/**
* Returns the initial bookmarks.
* First transaction in the session created with this {@link SessionConfig}
* will ensure that server hosting is at least as up-to-date as the
* latest transaction referenced by the supplied initial bookmarks.
*
* @return the initial bookmarks.
*/
public Iterable bookmarks() {
return bookmarks;
}
/**
* The type of access required by units of work in this session,
* e.g. {@link AccessMode#READ read access} or {@link AccessMode#WRITE write access}.
*
* @return the access mode.
*/
public AccessMode defaultAccessMode() {
return defaultAccessMode;
}
/**
* The database where the session is going to connect to.
*
* @return the nullable database name where the session is going to connect to.
*/
public Optional database() {
return Optional.ofNullable(database);
}
/**
* This value if set, overrides the default fetch size set on {@link Config#fetchSize()}.
*
* @return an optional value of fetch size.
*/
public Optional fetchSize() {
return Optional.ofNullable(fetchSize);
}
/**
* The impersonated user the session is going to use for query execution.
*
* @return an optional value of the impersonated user.
*/
public Optional impersonatedUser() {
return Optional.ofNullable(impersonatedUser);
}
/**
* A {@link BookmarkManager} implementation for the session to use.
*
* @return bookmark implementation
*/
@Experimental
public Optional bookmarkManager() {
return Optional.ofNullable(bookmarkManager);
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
SessionConfig that = (SessionConfig) o;
return Objects.equals(bookmarks, that.bookmarks)
&& defaultAccessMode == that.defaultAccessMode
&& Objects.equals(database, that.database)
&& Objects.equals(fetchSize, that.fetchSize)
&& Objects.equals(impersonatedUser, that.impersonatedUser)
&& Objects.equals(bookmarkManager, that.bookmarkManager);
}
@Override
public int hashCode() {
return Objects.hash(bookmarks, defaultAccessMode, database, impersonatedUser, bookmarkManager);
}
@Override
public String toString() {
return String.format(
"""
SessionParameters{bookmarks=%s, defaultAccessMode=%s, database='%s', fetchSize=%d, impersonatedUser=%s, \
bookmarkManager=%s}\
""",
bookmarks, defaultAccessMode, database, fetchSize, impersonatedUser, bookmarkManager);
}
/**
* Builder used to configure {@link SessionConfig} which will be used to create a session.
*/
public static final class Builder {
private Long fetchSize = null;
private Iterable bookmarks = null;
private AccessMode defaultAccessMode = AccessMode.WRITE;
private String database = null;
private String impersonatedUser = null;
private BookmarkManager bookmarkManager;
private Builder() {}
/**
* Set the initial bookmarks to be used in a session.
*
* First transaction in a session will ensure that server hosting is at least as up-to-date as the latest transaction referenced by the supplied
* bookmarks. The bookmarks can be obtained via {@link Session#lastBookmarks()}, {@link AsyncSession#lastBookmarks()}, and/or {@link
* ReactiveSession#lastBookmarks()}.
*
* @param bookmarks a series of initial bookmarks. Both {@code null} value and empty array are permitted, and indicate that the bookmarks do not exist
* or are unknown.
* @return this builder.
*/
public Builder withBookmarks(Bookmark... bookmarks) {
if (bookmarks == null) {
this.bookmarks = null;
} else {
this.bookmarks = Arrays.asList(bookmarks);
}
return this;
}
/**
* Set the initial bookmarks to be used in a session. First transaction in a session will ensure that server hosting is at least as up-to-date as the
* latest transaction referenced by the supplied bookmarks. The bookmarks can be obtained via {@link Session#lastBookmarks()}, {@link
* AsyncSession#lastBookmarks()}, and/or {@link ReactiveSession#lastBookmarks()}.
*
* Multiple immutable sets of bookmarks may be joined in the following way:
*
* {@code
* Set bookmarks = new HashSet<>();
* bookmarks.addAll( session1.lastBookmarks() );
* bookmarks.addAll( session2.lastBookmarks() );
* bookmarks.addAll( session3.lastBookmarks() );
* }
*
*
* @param bookmarks initial references to some previous transactions. Both {@code null} value and empty iterable are permitted, and indicate that the
* bookmarks do not exist or are unknown.
* @return this builder
*/
public Builder withBookmarks(Iterable bookmarks) {
this.bookmarks = bookmarks;
return this;
}
/**
* Set the type of access required by units of work in this session,
* e.g. {@link AccessMode#READ read access} or {@link AccessMode#WRITE write access}.
* This access mode is used to route transactions in the session to the server who has the right to carry out the specified operations.
*
* @param mode access mode.
* @return this builder.
*/
public Builder withDefaultAccessMode(AccessMode mode) {
this.defaultAccessMode = mode;
return this;
}
/**
* Set the database that the newly created session is going to connect to.
*
* For connecting to servers that support multi-databases,
* it is highly recommended to always set the database explicitly in the {@link SessionConfig} for each session.
* If the database name is not set, then session defaults to connecting to the default database configured in server configuration.
*
* For servers that do not support multi-databases, leave this database value unset. The only database will be used instead.
*
* @param database the database the session going to connect to. Provided value should not be {@code null}.
* @return this builder.
*/
public Builder withDatabase(String database) {
requireNonNull(database, "Database name should not be null.");
if (database.isEmpty()) {
// Empty string is an illegal database name. Fail fast on client.
throw new IllegalArgumentException(String.format("Illegal database name '%s'.", database));
}
this.database = database;
return this;
}
/**
* Specify how many records to fetch in each batch for this session.
* This config will overrides the default value set on {@link Config#fetchSize()}.
* This config is only valid when the driver is used with servers that support Bolt V4 (Server version 4.0 and later).
*
* Bolt V4 enables pulling records in batches to allow client to take control of data population and apply back pressure to server.
* This config specifies the default fetch size for all query runs using {@link Session} and {@link AsyncSession}.
* By default, the value is set to {@code 1000}.
* Use {@code -1} to disables back pressure and config client to pull all records at once after each run.
*
* This config only applies to run result obtained via {@link Session} and {@link AsyncSession}.
* As with {@link RxSession}, the batch size is provided via {@link Subscription#request(long)} instead.
* @param size the default record fetch size when pulling records in batches using Bolt V4.
* @return this builder
*/
public Builder withFetchSize(long size) {
this.fetchSize = assertValidFetchSize(size);
return this;
}
/**
* Set the impersonated user that the newly created session is going to use for query execution.
*
* The principal provided to the driver on creation must have the necessary permissions to impersonate and run queries as the impersonated user.
*
* When {@link #withDatabase(String)} is not used, the driver will discover the default database name of the impersonated user on first session usage.
* From that moment, the discovered database name will be used as the default database name for the whole lifetime of the new session.
*
* Compatible with 4.4+ only. You MUST have all servers running 4.4 version or above and communicating over Bolt 4.4 or above.
*
* @param impersonatedUser the user to impersonate. Provided value should not be {@code null}.
* @return this builder
*/
public Builder withImpersonatedUser(String impersonatedUser) {
requireNonNull(impersonatedUser, "Impersonated user should not be null.");
if (impersonatedUser.isEmpty()) {
// Empty string is an illegal user. Fail fast on client.
throw new IllegalArgumentException(String.format("Illegal impersonated user '%s'.", impersonatedUser));
}
this.impersonatedUser = impersonatedUser;
return this;
}
/**
* Sets a {@link BookmarkManager} implementation for the session to use.
*
* By default, bookmark manager is effectively disabled.
*
* @param bookmarkManager bookmark manager implementation. Providing {@code null} effectively disables bookmark manager.
* @return this builder.
*/
@Experimental
public Builder withBookmarkManager(BookmarkManager bookmarkManager) {
this.bookmarkManager = bookmarkManager;
return this;
}
public SessionConfig build() {
return new SessionConfig(this);
}
}
}