TL;DR

Elastisch is a battle tested, small but feature rich and well documented Clojure client for ElasticSearch. It supports virtually every Elastic Search feature and has solid documentation.

2.1.0 is feature release.

Changes between Elastisch 2.0.x and 2.1.0

Clojure 1.4 Support Dropped

Elastisch no longer officially supports Clojure 1.4. Most of the functionality still works well on that version but please don’t file bugs specific to that version.

Allow :index key in update-aliases (native)

clojurewerkz.elastisch.native.index/update-aliases expects indices to be added to be specified in the :indices key while the respective REST function uses :index. This can have unexpected results, namely the creation of the respective alias for all indices. It is now possible to supply either :index or :indices to the function.

GH issue: #108.

Contributed by Yannick Scherer (stylefruits)

Update with Partial Document via native API

clojurewerkz.elastisch.native.document/update-with-partial-doc is a new function in the Native Client (existed before in the REST API) that performs partial updates:

(require '[clojurewerkz.elastisch.native.document :as doc])

(doc/update-with-partial-doc conn "people" "person" "1" {:country "Sweden"})

Note that the REST API should now be called without wrapping the document in a :doc key. I.e. change {:doc {:field-to-update "Update"}} to {:field-to-update "Update"}.

Contributed by Sandeep Jagtap and Henrik Lundahl.

Ability to Specify Aliases In index.create-template

clojurewerkz.elastisch.rest.index.create-template now supports the :aliases option:

(require '[clojurewerkz.elastisch.rest.index :as idx])

(idx/create-template conn "accounts" {:template "account*" :settings {:index {:refresh_interval "60s"}} :aliases {:account-alias {}}})

Contributed by Jeffrey Erikson.

clj-http Update

clj-http dependency has been upgraded to version 1.0.x.

Allow Retry On Conflict Option

Updates and upserts now allow the retry-on-conflict option to be set. This helps to work around Elasticsearch version conflicts.

GH issue: #119.

Contributed by Michael Nussbaum (Braintree).

REST API Bulk Indexing Filters Out Operation Keys

clojurewerkz.elastisch.rest.bulk/bulk-index now filters out all operation/option keys so that they don’t get stored in the document body.

GH issue: #116.

Contributed by Michael Nussbaum (Braintree).

New Line in Multi-Search REST API

ElasticSearch Multi Search REST API endpoint is sensitive to the trailing new line. When it is missing, the response contains one result too few.

Elastisch now makes sure to append a new line to Multi Search request bodies.

Correct async-put in Native Client

Native client’s document/async-put no longer fails with an exception.

Contributed by Nikita Burtsev.

ElasticSearch Native Client Upgrade

Elastisch now depends on ElasticSearch native client version 1.4.x.

Single-Bucket Aggregation Fix in the Native Client

Child aggregations in single-bucket aggregations (i.e. “global”) are no longer silently dropped.

Contributed by Yannick Scherer (StyleFruits).

Aggregations Support in the Native Client

Native client now has support for aggregations.

The API is the same as in the REST client.

Note that ElasticSearch 1.2 has 26 aggregations. Currently only the most commonly used ones are supported but support for more types will be added eventually. The supported types are:

  • Avg
  • Max
  • Min
  • Sum
  • Stats
  • Extended stats
  • Cardinality, value count
  • Percentiles
  • Histogram
  • Date Histogram
  • Range
  • Date Range
  • Terms
  • Missing
  • Global

Multi-Search Support in the Native Client

Native client now has support for multi-search.

The API is the same as in the REST client except that the functions are in the clojurewerkz.elastisch.native.multi.

Extra Options on Upserts

clojurewerkz.elastisch.native.document/upsert now accepts a map of extra options, e.g. parent document ID:

(doc/upsert conn index-name index-type id doc {:parent parent-id})

Terms Query Helper

clojurewerkz.elastisch.query/terms is a newly added alias for clojurewerkz.elastisch.query/term when used with a collection.

Contributed by Martin Klepsch.

Remove Alias Now Works in Native Client

Bug fixed in native client for removing aliases from indices and improved inline documentation. See aliases in the guide.

GH issue: #98.

Highlighting Support in Native Client

Native client now supports (most of the) highlighting features the REST client does:

(require '[clojurewerkz.elastisch.native.document :as doc])
(require '[clojurewerkz.elastisch.query :as q])

(doc/search conn index type
            {:query (q/query-string :query "software" :default_field "summary")
             :highlight {:fields {:summary {}}}})

Per Connection clj-http Options in REST Client

It is now possible to specify clj-http options for REST API connections, e.g. to specify a timeout:

(esr/connect "http://127.0.0.1:9200/" {:conn-timeout 1000
                                       :basic-auth ["username" "pa$$w0rd"]})

Source Filtering Support in Native Client

Native client now supports source filtering just like the REST API client:

(doc/search conn index-name mapping-type
            :query   (q/match-all)
            :sort    {"first-name" "asc"}
            :_source ["first-name" "age"])

(doc/search conn index-name mapping-type
            :query   (q/match-all)
            :sort    {"first-name" "asc"}
            :_source {"exclude" ["title" "country"
                                 "planet" "biography"
                                 "last-name" "username"]})

GH issue: #73.

Search Can Return Fields and Source

Previously a search would return either the source document, or specific fields and not both. There are certain circumstances where having both are beneficial, for example when searching for a child document and you want to include the parent ID:

(require '[clojurewerkz.elastisch.native.document :as esd])

(esd/search conn "index" "child-type" :query (q/match-all) :fields ["_parent"])

The above would return the parent document ID in the :_parent field of each hit, but would not return the document itself. You can now have both by:

(esd/search conn "index" "child-type" :query (q/match-all) :fields ["_parent" "_source"])

Now the parent ID is in the :_parent field of each hit, and the matching document will be in :_source as per a normal search.

Contributed by Ben Ashford.

Full Change Log

Elastisch change log is available on GitHub.

Elastisch is a ClojureWerkz Project

Elastisch is part of the group of libraries known as ClojureWerkz, together with

  • Langohr, a Clojure client for RabbitMQ that embraces the AMQP 0.9.1 model
  • Monger, a Clojure MongoDB client for a more civilized age
  • Cassaforte, a Clojure Cassandra client
  • Titanium, a Clojure graph library
  • Neocons, a client for the Neo4J REST API
  • Welle, a Riak client with batteries included
  • Quartzite, a powerful scheduling library

and several others. If you like Elastisch, you may also like our other projects.

Let us know what you think on Twitter or on the Clojure mailing list.

About the Author

Michael on behalf of the ClojureWerkz Team