# `khepri_mnesia_migration`: Mnesia⬌Khepri migration toolkit
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`khepri_mnesia_migration` is a library providing helpers to migrate data
between the Mnesia and Khepri databases.
Currently, only the migration from Mnesia to Khepri is supported.
<img align="right" height="150" src="/doc/kmm-logo.svg">
## Project maturity
`khepri_mnesia_migration` is still under active development and should be
considered *Alpha* at this stage.
## Documentation
* A short tutorial in the [Getting started](#getting-started) section below
* [Documentation and API reference](https://rabbitmq.github.io/khepri_mnesia_migration/)
## Getting started
### Add as a dependency
Add `khepri_mnesia_migration` as a dependency of your project:
Using Rebar:
```erlang
%% In rebar.config
{deps, [{khepri_mnesia_migration, "0.1.0"}]}.
```
Using Erlang.mk:
```make
# In your Makefile
DEPS += khepri_mnesia_migration
dep_khepri_mnesia_migration = hex 0.1.0
```
Using Mix:
```elixir
# In mix.exs
defp deps do
[
:khepri_mnesia_migration, "0.1.0"}
]
end
```
### Synchronize cluster members
To ensure a Khepri store has the same members as the Mnesia cluster, use
`mnesia_to_khepri:synchronize_cluster_membership/{0,1}`:
```erlang
mnesia_to_khepri:synchronize_cluster_membership(StoreId).
```
### Copy Mnesia tables to a Khepri store
You can copy Mnesia tables records to a Khepri store using
`mnesia_to_khepri:copy_tables/{2,3}`. It takes a converter module which takes
care of actually processing each Mnesia records (if needed) and storing them in
the Khepri store. A converter module called
`mnesia_to_khepri_example_converter` is provided for common use cases and as an
example.
```erlang
mnesia_to_khepri:copy_all_tables(mnesia_to_khepri_example_converter).
```
## How to build
### Build
```
rebar3 compile
```
### Build documentation
```
rebar3 edoc
```
### Test
```
rebar3 xref
rebar3 eunit
rebar3 ct --sname ct
rebar3 as test dialyzer
```
## Copyright and License
© 2022-2023 VMware, Inc. or its affiliates.
This work is dual-licensed under the Apache License 2.0 and the Mozilla Public
License 2.0. You can choose between one of them if you use this work.
SPDX-License-Identifier: Apache-2.0 OR MPL-2.0