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.
1.1.0 includes several new features, most notably a native client with the same API as the REST one Elastisch already has.
Supported ElasticSearch Versions
Elastisch 1.1’s native client requires ElasticSearch 0.90.0. ElasticSearch still evolves rapidly and binary protocol changes quite often, so the version match between the client and the server is currently a requirement for binary clients.
This restriction does not apply to REST API clients.
Changes in 1.1.0
Native Client
Elastisch 1.1.0
includes a major new feature: native ElasticSearch client.
The client uses ElasticSearch’s Java API, and can be used with
both transport and node clients.
Rationale
Native client is more bandwidth efficient. It also can use SMILE (binary JSON format) to be more efficient on the wire.
Namespace Layout
Native client API in Elastisch is nearly identical to that of the REST API client
and resides in clojurewerkz.elastisch.native
and clojurewerkz.elastisch.native.*
namespaces (similarly to how clojurewerkz.elastisch.rest
clojurewerkz.elastisch.rest.*
namespaces are organized).
Connections
Transport client (used for TCP/remote connections) connections are set up using
clojurewerkz.elastisch.native/connect!
. Note that you need to provide node
configuration that at least has cluster name in it:
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Cluster name and transport node addresses can be retrieved via HTTP API, for example:
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Performing Operations
The Native client tries to be as close as possible to the existing REST client API.
For example, document operation functions in clojurewerkz.elastisch.native.document
,
such as clojurewerkz.elastisch.native.document/create
,
follow clojurewerkz.elastisch.rest.document
function signatures as closely as
possible:
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The same with returned results. Note, however, that ES transport client does have (very) minor differences with the REST API and it is not always possible for Elastisch to completely cover such differences.
Async Operations
Native client offers a choice of synchronous (blocking calling thread until a response is received) and asynchronous (returns a future) versions of multiple API operations:
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One notable exception to this is administrative operations (such as opening or closing an index). The rationale for this is that they are rarely executed on the hot code path (e.g. in tight loops), so convenience and better error visibility is more important for them.
GH issues: #17, #18, #20.
Clojure 1.5 By Default
Elastisch now depends on org.clojure/clojure
version 1.5.0
. It is still compatible with Clojure 1.3+ and if your project.clj
depends
on 1.3 or 1.4, it will be used, but 1.5 is the default now.
We encourage all users to upgrade to 1.5, it is a drop-in replacement for the majority of projects out there.
Bulk Request Support
Bulk requests are now supported. All the relevant code is in the clojurewerkz.elastisch.rest.bulk
namespace. Here is a small example of bulk document indexing using this new API:
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Contributed by Davie Moston.
Scroll Queries Support
Scroll queries are now easier to perform thanks to the new clojurewerkz.elastisch.rest.document/scroll
function that takes a scroll id and amount of time retrieved documents and related information
will be kept in memory for future retrieval. They are analogous to database cursors.
A short code example:
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Contributed by Davie Moston.
Cheshire Update
Cheshire dependency has been upgraded to version 5.1.1
.
clj-http Update
clj-http dependency has been upgraded to version 0.7.2
.
Count API No Longer Ignores Mapping Types
clojurewerkz.elastisch.rest.document/count
no longer ignores mapping types.
GH issue: #6.
Count API now uses GET requests
clojurewerkz.elastisch.rest.document/count
now correctly uses GET
for requests without
the query part andPOST
for request that have it.
GH issue: #5.
Updates With Scripts
clojurewerkz.elastisch.rest.document/update-with-script
is a new function
that updates a document with a provided script:
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clojurewerkz.elastisch.native.document/update-with-script
is the native
client counterpart that takes the same arguments.
Change Log
Elastisch change log is available on GitHub.
Thank You, Contributors
Kudos to Davie Moston, Andrew Jones, Jon Pither and Antonio Terreno who contributed to this release.
Elastisch is a ClojureWerkz Project
Elastisch is part of the group of libraries known as ClojureWerkz, together with
- Welle, a Riak client with batteries included
- Monger, a Clojure MongoDB client for a more civilized age
- Neocons, a client for the Neo4J REST API
- Langohr, a Clojure client for RabbitMQ that embraces the AMQP 0.9.1 model
- 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.
Michael on behalf of the ClojureWerkz Team