This tutorial shows you how to load streaming data into Apache Druid (incubating) using HTTP push via Tranquility Server.
Tranquility Server allows a stream of data to be pushed into Druid using HTTP POSTs.
For this tutorial, we'll assume you've already downloaded Druid as described in the single-machine quickstart and have it running on your local machine. You don't need to have loaded any data yet.
In the Druid package root, run the following commands:
curl http://static.druid.io/tranquility/releases/tranquility-distribution-0.8.3.tgz -o tranquility-distribution-0.8.3.tgz tar -xzf tranquility-distribution-0.8.3.tgz mv tranquility-distribution-0.8.3 tranquility
The startup scripts for the tutorial will expect the contents of the Tranquility tarball to be located at
tranquility under the apache-druid-0.14.1-incubating package root.
quickstart/tutorial/conf/tutorial-cluster.conf, uncomment the
bin/supervise -c quickstart/tutorial/conf/tutorial-cluster.conf.
As part of the output of supervise you should see something like:
Running command[tranquility-server], logging to[/stage/apache-druid-0.14.1-incubating/var/sv/tranquility-server.log]: tranquility/bin/tranquility server -configFile quickstart/tutorial/conf/tranquility/server.json -Ddruid.extensions.loadList=
You can check the log file in
var/sv/tranquility-server.log to confirm that the server is starting up properly.
Let's send the sample Wikipedia edits data to Tranquility:
gunzip -k quickstart/tutorial/wikiticker-2015-09-12-sampled.json.gz curl -XPOST -H'Content-Type: application/json' --data-binary @quickstart/tutorial/wikiticker-2015-09-12-sampled.json http://localhost:8200/v1/post/wikipedia
Which will print something like:
This indicates that the HTTP server received 39,244 events from you, and sent 39,244 to Druid. This command may generate a "connection refused" error if you run it too quickly after enabling Tranquility Server, which means the server has not yet started up. It should start up within a few seconds. The command may also take a few seconds to finish the first time you run it, during which time Druid resources are being allocated to the ingestion task. Subsequent POSTs will complete quickly once this is done.
Once the data is sent to Druid, you can immediately query it.
If you see a
sent count of 0, retry the send command until the
sent count also shows 39244:
Please follow the query tutorial to run some example queries on the newly loaded data.
If you wish to go through any of the other ingestion tutorials, you will need to shut down the cluster and reset the cluster state by removing the contents of the
var directory under the druid package, as the other tutorials will write to the same "wikipedia" datasource.
When cleaning up after running this Tranquility tutorial, it is also necessary to recomment the
tranquility-server line in
quickstart/tutorial/conf/tutorial-cluster.conf before restarting the cluster.
For more information on Tranquility, please see the Tranquility documentation.