Mongo2ES:
- Mongo2ES syncs data from MongoDB to ElasticSearch.
- Also automatically removes documents from ElasticSearch if they are removed in MongoDB.
- Mongo2ES is built with MeteorJs.
Why does this exist?
- ElasticSearch rivers are deprecated
- Transporter by compose is kind of stuck and unable to remove ES documents when they are removed in MongoDB.
Installation
install without docker
Mongo2ES runs as a Meteor application, so you need to have Meteor installed, first.
curl https://install.meteor.com/ | sh
then clone and run it
git clone https://github.com/Alino/Mongo2ES.git
cd Mongo2ES
elasticsearchHost="127.0.0.1:9200" meteor --port 3001
install as docker container:
git clone https://github.com/Alino/Mongo2ES.git && cd Mongo2ES
docker build -t kuknito/mongo2es .
docker run --name Mongo2ES -d \
-e ROOT_URL=http://localhost:3001 \
-e MONGO_URL="mongodb://127.0.0.1:27017/dbname?replicaSet=rs&readPreference=primaryPreferred&w=majority&connectTimeoutMS=60000&socketTimeoutMS=60000" \
-e MONGO_OPLOG_URL=mongodb://127.0.0.1:27017/local \
-e elasticsearchHost="127.0.0.1:9200" \
-p 3001:80 \
kuknito/mongo2es
note: the docker image is also available at docker hub as an automated build. https://hub.docker.com/r/alino/mongo2es/
install as a Meteor package
meteor add alino:mongo2es
https://github.com/Alino/alino-mongo2es
environment variables
env variable | description |
---|---|
MONGO_URL | MongoDB url |
MONGO_OPLOG_URL | MongoDB oplog url |
elasticsearchHost | URL which defines your ES host. (including port) |
logitHost | URL of your logstash host (optional) |
logitPort | logstash port (optional) |
Syncing data from MongoDB to ElasticSearch
If you want to sync MongoDB to ElasticSearch, you must define which collections you want to watch. For that, you have to write your watchers.
creating a watcher
If you are ready to write your own watchers,
go and create new file watchers.js
in the project root.
Then you create a watcher by creating new object from Mongo2ES class:
if(Meteor.isServer) {
Meteor.startup(function() {
new Mongo2ES(options);
});
}
options:
options = {
collectionName: // String - name of the mongoDB collection you want to watch
ES: {
host: // String - url of your ElasticSearch host where you want to copy the data to.
index: // String - ElasticSearch index
type: // String - ElasticSearch type
},
transform: // Function - modify the document before copying it to ElasticSearch. Takes 1 argument - the document and should return the modified document.
copyAlreadyExistingData: // Boolean - true if it should copy all existing data in this collection ( default: false )
}
examples of watchers
You can get inspired from this example file
watchersExample.md
stopping a watcher
watcher = new Mongo2ES(options); // create a watcher and put it into a variable
watcher.stopWatch() // stops the watcher
logging
there are currently 2 options for logging in Mongo2ES.
- Default behavior - simply shows up the logs, like
console.log()
does - logging to ElasticSearch with logstash - to enable this feature, you must set logitHost and logitPort environment variables.
Both logging options are using Meteor package alino:logit
limitations:
- only one mongo database can be synced to ES, because we are tailing single MONGO_OPLOG_URL