Chapter 3. Migrating data between cache stores
Data Grid provides a Java utility for migrating persisted data between cache stores.
In the case of upgrading Data Grid, functional differences between major versions do not allow backwards compatibility between cache stores. You can use StoreMigrator
to convert your data so that it is compatible with the target version.
For example, upgrading to Data Grid 8.0 changes the default marshaller to Protostream. In previous Data Grid versions, cache stores use a binary format that is not compatible with the changes to marshalling. This means that Data Grid 8.0 cannot read from cache stores with previous Data Grid versions.
In other cases Data Grid versions deprecate or remove cache store implementations, such as JDBC Mixed and Binary stores. You can use StoreMigrator
in these cases to convert to different cache store implementations.
3.1. Cache store migrator
Data Grid provides the StoreMigrator.java
utility that recreates data for the latest Data Grid cache store implementations.
StoreMigrator
takes a cache store from a previous version of Data Grid as source and uses a cache store implementation as target.
When you run StoreMigrator
, it creates the target cache with the cache store type that you define using the EmbeddedCacheManager
interface. StoreMigrator
then loads entries from the source store into memory and then puts them into the target cache.
StoreMigrator
also lets you migrate data from one type of cache store to another. For example, you can migrate from a JDBC string-based cache store to a RocksDB cache store.
StoreMigrator
cannot migrate data from segmented cache stores to:
- Non-segmented cache store.
- Segmented cache stores that have a different number of segments.
3.2. Getting the cache store migrator
StoreMigrator
is available as part of the Data Grid tools library, infinispan-tools
, and is included in the Maven repository.
Procedure
Configure your
pom.xml
forStoreMigrator
as follows:<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>org.infinispan.example</groupId> <artifactId>jdbc-migrator-example</artifactId> <version>1.0-SNAPSHOT</version> <dependencies> <dependency> <groupId>org.infinispan</groupId> <artifactId>infinispan-tools</artifactId> </dependency> <!-- Additional dependencies --> </dependencies> <build> <plugins> <plugin> <groupId>org.codehaus.mojo</groupId> <artifactId>exec-maven-plugin</artifactId> <version>1.2.1</version> <executions> <execution> <goals> <goal>java</goal> </goals> </execution> </executions> <configuration> <mainClass>org.infinispan.tools.store.migrator.StoreMigrator</mainClass> <arguments> <argument>path/to/migrator.properties</argument> </arguments> </configuration> </plugin> </plugins> </build> </project>
3.3. Configuring the cache store migrator
Set properties for source and target cache stores in a migrator.properties
file.
Procedure
-
Create a
migrator.properties
file. Configure the source cache store in
migrator.properties
.Prepend all configuration properties with
source.
as in the following example:source.type=SOFT_INDEX_FILE_STORE source.cache_name=myCache source.location=/path/to/source/sifs source.version=<version>
Configure the target cache store in
migrator.properties
.Prepend all configuration properties with
target.
as in the following example:target.type=SINGLE_FILE_STORE target.cache_name=myCache target.location=/path/to/target/sfs.dat
3.3.1. Configuration properties for the cache store migrator
Configure source and target cache stores in a StoreMigrator
properties.
Property | Description | Required/Optional |
---|---|---|
| Specifies the type of cache store type for a source or target.
| Required |
Property | Description | Example Value | Required/Optional |
---|---|---|---|
| Names the cache that the store backs. |
| Required |
| Specifies the number of segments for target cache stores that can use segmentation.
The number of segments must match In other words, the number of segments for a cache store must match the number of segments for the corresponding cache. If the number of segments is not the same, Data Grid cannot read data from the cache store. |
| Optional |
Property | Description | Required/Optional |
---|---|---|
| Specifies the dialect of the underlying database. | Required |
|
Specifies the marshaller version for source cache stores.
*
*
*
*
*
* | Required for source stores only. |
| Specifies a custom marshaller class. | Required if using custom marshallers. |
|
Specifies a comma-separated list of custom | Optional |
| Specifies the JDBC connection URL. | Required |
| Specifies the class of the JDBC driver. | Required |
| Specifies a database username. | Required |
| Specifies a password for the database username. | Required |
| Sets the database major version. | Optional |
| Sets the database minor version. | Optional |
| Disables database upsert. | Optional |
| Specifies if table indexes are created. | Optional |
| Specifies additional prefixes for the table name. | Optional |
| Specifies the column name. | Required |
| Specifies the column type. | Required |
|
Specifies the | Optional |
To migrate from Binary cache stores in older Data Grid versions, change table.string.*
to table.binary.\*
in the following properties:
-
source.table.binary.table_name_prefix
-
source.table.binary.<id\|data\|timestamp>.name
-
source.table.binary.<id\|data\|timestamp>.type
# Example configuration for migrating to a JDBC String-Based cache store target.type=STRING target.cache_name=myCache target.dialect=POSTGRES target.marshaller.class=org.example.CustomMarshaller target.marshaller.externalizers=25:Externalizer1,org.example.Externalizer2 target.connection_pool.connection_url=jdbc:postgresql:postgres target.connection_pool.driver_class=org.postrgesql.Driver target.connection_pool.username=postgres target.connection_pool.password=redhat target.db.major_version=9 target.db.minor_version=5 target.db.disable_upsert=false target.db.disable_indexing=false target.table.string.table_name_prefix=tablePrefix target.table.string.id.name=id_column target.table.string.data.name=datum_column target.table.string.timestamp.name=timestamp_column target.table.string.id.type=VARCHAR target.table.string.data.type=bytea target.table.string.timestamp.type=BIGINT target.key_to_string_mapper=org.infinispan.persistence.keymappers. DefaultTwoWayKey2StringMapper
Property | Description | Required/Optional |
---|---|---|
| Sets the database directory. | Required |
| Specifies the compression type to use. | Optional |
# Example configuration for migrating from a RocksDB cache store. source.type=ROCKSDB source.cache_name=myCache source.location=/path/to/rocksdb/database source.compression=SNAPPY
Property | Description | Required/Optional |
---|---|---|
|
Sets the directory that contains the cache store | Required |
# Example configuration for migrating to a Single File cache store. target.type=SINGLE_FILE_STORE target.cache_name=myCache target.location=/path/to/sfs.dat
Property | Description | Value |
---|---|---|
Required/Optional |
| Sets the database directory. |
Required |
| Sets the database index directory. |
# Example configuration for migrating to a Soft-Index File cache store. target.type=SOFT_INDEX_FILE_STORE target.cache_name=myCache target.location=path/to/sifs/database target.location=path/to/sifs/index
3.4. Migrating Data Grid cache stores
Run StoreMigrator
to migrate data from one cache store to another.
Prerequisites
-
Get
infinispan-tools.jar
. -
Create a
migrator.properties
file that configures the source and target cache stores.
Procedure
If you build
infinispan-tools.jar
from source, do the following:-
Add
infinispan-tools.jar
and dependencies for your source and target databases, such as JDBC drivers, to your classpath. -
Specify
migrator.properties
file as an argument forStoreMigrator
.
-
Add
If you pull
infinispan-tools.jar
from the Maven repository, run the following command:mvn exec:java