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A toolkit for using MongoDB with Clojure.


Version 0.1.7 adds the ability to create MongoOptions and pass them into make-connection as the last argument, so that you can control autoConnectRetry and timeouts and so on. This release also fixes a number of small bugs around type hints introduced in 0.1.6; corrects the upsert(?) parameter in fetch-and-modify; upgrades the Java driver to 2.6.5. The :only parameter can now be a map of field names and true / false values to allow fields to be included or excluded. The original vector of field names is still supported to include only the named fields.

Version 0.1.6 removes (almost) all of the reflection warnings.

Version 0.1.5 adds compatibility with both Clojure 1.3, in addition to 1.2.

Congomongo 0.1.4 introduces support for the MongoDB 1.8's modified map-reduce functionality, wherein the 'out' parameter is required. With this and future Congomongo releases, it will no longer be possible to access the map-reduce features of older MongoDB instances.

As of congomongo 0.1.3, Clojure 1.2 and Clojure-contrib 1.2 are required.
If you need compatibility with Clojure 1.1,
please stick with congomongo 0.1.2.

There is now a Google Group
Come help us make ponies for great good.

Clojars group is congomongo.

CongoMongo is essentially a Clojure api for the mongo-java-driver, transparently handling coercions between Clojure and Java data types.




(ns my-mongo-app
  (:use somnium.congomongo))

make a connection

(def conn mongo/make-connection "mydb"
                                :host ""
                                :port 27017) => #'user/conn

conn => {:mongo #<Mongo Mongo:>, :db #<DBApiLayer mydb>}

set the connection globally

(set-connection! conn)

or locally

(with-mongo conn
    (insert! :robots {:name "robby"}))

Simple Tasks


(insert! :robots
         {:name "robby"}


(def my-robot (fetch-one :robots)) => #'user/my-robot

my-robot => { :name "robby",
              :_id  #<ObjectId> "0c23396f7e53e34a4c8cf400">,
              :_ns  "robots"}


(update! :robots my-robot (merge my-robot { :name "asimo" }))

=>  { :name "asimo" ,
      :_id  #<ObjectId> "0c23396f7e53e34a4c8cf400"> ,
      :_ns : "robots" }


(destroy! :robots my-robot) => nil
(fetch :robots) => ()

More Sophisticated Tasks

mass inserts

  (for [x (range 100) y (range 100)]
    {:x x
     :y y
     :z (* x y)}))

 =>  nil

(fetch-count :points)
=> 10000

ad-hoc queries

  :where {:x {:$gt 10
              :$lt 20}
          :y 42
          :z {:$gt 500}})

=> {:x 12, :y 42, :z 504,  :_ns "points", :_id ... }


(authenticate conn "myusername" "my password")

=> true

advanced initialization using mongo-options

((make-connection :mydb :host "" (mongo-options :auto-connect-retry true)"

easy json

(fetch-one :points
           :as :json)

=> "{ \"_id\" : \"0c23396ffe79e34a508cf400\" ,
      \"x\" : 0 , \"y\" : 0 , \"z\" : 0 , \"_ns\" : \"points\"}"


Leiningen is the recommended way to use congomongo. Just add

[congomongo "0.1.7"]

to your project.clj and do

$lein deps

to get congomongo and all of its dependencies.


CongoMongo is a work in progress. If you've used, improved, or abused it tell us about it at our Google Group.