mongobee is a Java tool which helps you to manage changes in your MongoDB and synchronize them with your application. The concept is very similar to other db migration tools such as Liquibase or Flyway but without using XML/JSON/YML files.
The goal is to keep this tool simple and comfortable to use.
mongobee provides new approach for adding changes (change sets) based on Java classes and methods with appropriate annotations.
With Maven
<dependency>
<groupId>com.github.mongobee</groupId>
<artifactId>mongobee</artifactId>
<version>0.13</version>
</dependency>
With Gradle
compile 'org.javassist:javassist:3.18.2-GA' // workaround for ${javassist.version} placeholder issue*
compile 'com.github.mongobee:mongobee:0.13'
You need to instantiate Mongobee object and provide some configuration. If you use Spring can be instantiated as a singleton bean in the Spring context. In this case the migration process will be executed automatically on startup.
@Bean
public Mongobee mongobee(){
Mongobee runner = new Mongobee("mongodb://YOUR_DB_HOST:27017/DB_NAME");
runner.setDbName("yourDbName"); // host must be set if not set in URI
runner.setChangeLogsScanPackage(
"com.example.yourapp.changelogs"); // the package to be scanned for changesets
return runner;
}
Using mongobee without a spring context has similar configuration but you have to remember to run execute()
method to start a migration process.
Mongobee runner = new Mongobee("mongodb://YOUR_DB_HOST:27017/DB_NAME");
runner.setDbName("yourDbName"); // host must be set if not set in URI
runner.setChangeLogsScanPackage(
"com.example.yourapp.changelogs"); // package to scan for changesets
runner.execute(); // ------> starts migration changesets
Above examples provide minimal configuration. Mongobee
object provides some other possibilities (setters) to make the tool more flexible:
runner.setChangelogCollectionName(logColName); // default is dbchangelog, collection with applied change sets
runner.setLockCollectionName(lockColName); // default is mongobeelock, collection used during migration process
runner.setEnabled(shouldBeEnabled); // default is true, migration won't start if set to false
MongoDB URI format:
mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database[.collection]][?options]]
ChangeLog
contains bunch of ChangeSet
s. ChangeSet
is a single task (set of instructions made on a database). In other words ChangeLog
is a class annotated with @ChangeLog
and containing methods annotated with @ChangeSet
.
package com.example.yourapp.changelogs;
@ChangeLog
public class DatabaseChangelog {
@ChangeSet(order = "001", id = "someChangeId", author = "testAuthor")
public void importantWorkToDo(DB db){
// task implementation
}
}
Class with change sets must be annotated by @ChangeLog
. There can be more than one change log class but in that case order
argument should be provided:
@ChangeLog(order = "001")
public class DatabaseChangelog {
//...
}
ChangeLogs are sorted alphabetically by order
argument and changesets are applied due to this order.
Method annotated by @ChangeSet is taken and applied to the database. History of applied change sets is stored in a collection called dbchangelog
(by default) in your MongoDB
order
- string for sorting change sets in one changelog. Sorting in alphabetical order, ascending. It can be a number, a date etc.
id
- name of a change set, must be unique for all change logs in a database
author
- author of a change set
runAlways
- [optional, default: false] changeset will always be executed but only first execution event will be stored in dbchangelog collection
Method annotated by @ChangeSet
can have one of the following definition:
@ChangeSet(order = "001", id = "someChangeWithoutArgs", author = "testAuthor")
public void someChange1() {
// method without arguments can do some non-db changes
}
@ChangeSet(order = "002", id = "someChangeWithMongoDatabase", author = "testAuthor")
public void someChange2(MongoDatabase db) {
// type: com.mongodb.client.MongoDatabase : original MongoDB driver v. 3.x, operations allowed by driver are possible
// example:
MongoCollection<Document> mycollection = db.getCollection("mycollection");
Document doc = new Document("testName", "example").append("test", "1");
mycollection.insertOne(doc);
}
@ChangeSet(order = "003", id = "someChangeWithDb", author = "testAuthor")
public void someChange3(DB db) {
// This is deprecated in mongo-java-driver 3.x, use MongoDatabase instead
// type: com.mongodb.DB : original MongoDB driver v. 2.x, operations allowed by driver are possible
// example:
DBCollection mycollection = db.getCollection("mycollection");
BasicDBObject doc = new BasicDBObject().append("test", "1");
mycollection .insert(doc);
}
@ChangeSet(order = "004", id = "someChangeWithJongo", author = "testAuthor")
public void someChange4(Jongo jongo) {
// type: org.jongo.Jongo : Jongo driver can be used, used for simpler notation
// example:
MongoCollection mycollection = jongo.getCollection("mycollection");
mycollection.insert("{test : 1}");
}
@ChangeSet(order = "005", id = "someChangeWithSpringDataTemplate", author = "testAuthor")
public void someChange5(MongoTemplate mongoTemplate) {
// type: org.springframework.data.mongodb.core.MongoTemplate
// Spring Data integration allows using MongoTemplate in the ChangeSet
// example:
mongoTemplate.save(myEntity);
}
@ChangeSet(order = "006", id = "someChangeWithSpringDataTemplate", author = "testAuthor")
public void someChange5(MongoTemplate mongoTemplate, Environment environment) {
// type: org.springframework.data.mongodb.core.MongoTemplate
// type: org.springframework.core.env.Environment
// Spring Data integration allows using MongoTemplate and Environment in the ChangeSet
}
mongobee accepts Spring's org.springframework.context.annotation.Profile
annotation. If a change log or change set class is annotated with @Profile
,
then it is activated for current application profiles.
Example 1: annotated change set will be invoked for a dev
profile
@Profile("dev")
@ChangeSet(author = "testuser", id = "myDevChangest", order = "01")
public void devEnvOnly(DB db){
// ...
}
Example 2: all change sets in a changelog will be invoked for a test
profile
@ChangeLog(order = "1")
@Profile("test")
public class ChangelogForTestEnv{
@ChangeSet(author = "testuser", id = "myTestChangest", order = "01")
public void testingEnvOnly(DB db){
// ...
}
}
To enable the @Profile
integration, please inject org.springframework.core.env.Environment
to you runner.
@Bean @Autowired
public Mongobee mongobee(Environment environment) {
Mongobee runner = new Mongobee(uri);
runner.setSpringEnvironment(environment)
//... etc
}
mongobee depends on mongo-java-driver
. If your application has mongo-java-driver dependency too, there could be a library conflicts in some cases.
Exception:
com.mongodb.WriteConcernException: { "serverUsed" : "localhost" ,
"err" : "invalid ns to index" , "code" : 10096 , "n" : 0 ,
"connectionId" : 955 , "ok" : 1.0}
Workaround:
You can exclude mongo-java-driver from mongobee and use your dependency only. Maven example (pom.xml) below:
<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
<version>3.0.0</version>
</dependency>
<dependency>
<groupId>com.github.mongobee</groupId>
<artifactId>mongobee</artifactId>
<version>0.9</version>
<exclusions>
<exclusion>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
</exclusion>
</exclusions>
</dependency>