Manage datomic schema with ragtime.
In Datomic, changing an existing schema attribute is similar to accumulate a new schema attribute. Since its not possible to rollback and redo a transaction, it is recommended to set the migration strategy to ragtime.strategy/raise-error.
https://docs.datomic.com/cloud/schema/schema-change.html
First, add the following dependency to your project:
[ragtime.datomic "0.3.0"]
Once you have at least one migration, you can set up Ragtime. You'll need to build a configuration map that will tell Ragtime how to connect to your database, and where the migrations are. In the example below, we'll put the configuration in the user namespace:
(ns user
(:require [datomic.client.api :as datomic]
[ragtime.datomic :as rd]
[ragtime.repl :as repl]))
(def client (datomic/client {:server-type :peer-server
:access-key "myaccesskey"
:secret "mysecret"
:endpoint "localhost:8998"}))
(def conn (datomic/connect client {:db-name "hello"}))
(def migration (rd/create-migration :id [:db/ident :inv/sku
:db/valueType :db.type/string
:db/unique :db.unique/identity
:db/cardinality :db.cardinality/one]))
(def config
{:datastore (rd/create-connection conn)
:migrations [migration])
(repl/migrate config)This library will install an extra schema inn your database.
{:db/ident :ragtime.datomic/migration-id
:db/valueType :db.type/keyword
:db/unique :db.unique/value
:db/cardinality :db.cardinality/one}The following datum will be appended to each of the schema transactions.
[:db/add "datomic.tx" :ragtime.datomic/migration-id migration-id]
Copyright © 2019 Haokang Den
This program and the accompanying materials are made available under the terms of the Eclipse Public License 2.0 which is available at http://www.eclipse.org/legal/epl-2.0.