37fc967f00
* Add function to allow for query execution without validation, fixes #25 - Using s/defn to allow for client to decide when to use validation - Add new function (`execute`) to keep backward compatability - Fixed error in schema for `timeseries` - Updated README.md - Remove use of swiss-arrow * as pr review
106 lines
3.3 KiB
Markdown
106 lines
3.3 KiB
Markdown
# clj-druid
|
|
|
|
[](https://travis-ci.org/y42/clj-druid)
|
|
|
|
Clojure library for [Druid](http://druid.io/).
|
|
|
|
clj-druid eases druid integration providing a client as well as a set of [Schema] (https://github.com/Prismatic/schema) to validate queries.
|
|
Current version is up to date with latest query API from official docs.
|
|
|
|
## Installing
|
|
|
|
Add the following to your [Leiningen](http://github.com/technomancy/leiningen) `project.clj`:
|
|
|
|
|
|
|
|
## Usage
|
|
|
|
### Client
|
|
|
|
Connect to a druid cluster through Zookeeper,
|
|
this method supports auto detection and update of available brokers for easy HA/load balancing
|
|
|
|
```clj
|
|
(use 'clj-druid.client)
|
|
(connect {:zk {:host "127.0.0.1:2181,my-other-zk-host:2181" ; can contain multiple hosts separated by commas
|
|
:discovery-path "/druid/discovery"
|
|
:node-type "druid:broker"}})
|
|
```
|
|
|
|
you can also connect by supplying a vector of hosts, useful for dev, local testing
|
|
|
|
```clj
|
|
(use 'clj-druid.client)
|
|
(connect {:hosts ["http://127.0.0.1:8083/druid/v2"]})
|
|
```
|
|
|
|
### Querying
|
|
|
|
Issue druid queries supplying
|
|
* a load balance strategy [fixed random]
|
|
* a queryType
|
|
* a query in the following form
|
|
|
|
```clj
|
|
(def q
|
|
{:queryType :timeseries
|
|
:dataSource "sample_datasource"
|
|
:granularity :day
|
|
:filter {
|
|
:type :and
|
|
:fields [
|
|
{:type :selector :dimension "sample_dimension1" :value "sample_value1"}
|
|
{:type :or
|
|
:fields [
|
|
{:type :selector :dimension "sample_dimension2" :value "sample_value2"}
|
|
{:type :selector :dimension "sample_dimension3" :value "sample_value3"}]}]}
|
|
:aggregations [
|
|
{:type :longSum :name "sample_name1", :fieldName "sample_fieldName1"}
|
|
{:type :doubleSum :name "sample_name2", :fieldName "sample_fieldName2"}]
|
|
:postAggregations [
|
|
{:type :arithmetic
|
|
:name "sample_divide"
|
|
:fn "/"
|
|
:fields [{:type :fieldAccess :name "sample_name1" :fieldName "sample_fieldName1"}
|
|
{:type :fieldAccess :name "sample_name2" :fieldName "sample_fieldName2"}]}]
|
|
|
|
:intervals ["2012-01-01T00:00:00.000/2012-01-03T00:00:00.000"]})
|
|
(let [client (connect {:zk {:host "127.0.0.1:2181"
|
|
:discovery-path "/druid/discovery"
|
|
:node-type "druid:broker"}})]
|
|
(query client random (:queryType q) q)
|
|
(close client))
|
|
```
|
|
To run a query _without_ runtime validation of the query against a schema (using
|
|
the `q` from above:
|
|
```clj
|
|
(let [client (connect {:zk {:host "127.0.0.1:2181"
|
|
:discovery-path "/druid/discovery"
|
|
:node-type "druid:broker"}})]
|
|
(execute client random q)
|
|
(close client))
|
|
;; if you want to validate
|
|
(let [client (connect {:zk {:host "127.0.0.1:2181"
|
|
:discovery-path "/druid/discovery"
|
|
:node-type "druid:broker"}})]
|
|
(s/with-fn-validation (execute client random q)) ;; s is plumatic/schema
|
|
(close client))
|
|
```
|
|
### Example
|
|
|
|
An example using compojure-api to spawn a full druid API is located in the examples folder
|
|
|
|
```bash
|
|
git clone https://github.com/y42/clj-druid
|
|
cd clj-druid/examples
|
|
lein ring server
|
|
```
|
|
|
|
Have Fun!
|
|
|
|
## License
|
|
|
|
Copyright © 2015 Guillaume Buisson
|
|
|
|
Distributed under the Eclipse Public License, the same as Clojure.
|
|
|