minor: update README and convert to markdown

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Kyle Banker 2010-11-02 16:09:43 -04:00
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@ -1,78 +1,75 @@
= Introduction
# Introduction
This is the 10gen-supported Ruby driver for MongoDB[http://www.mongodb.org].
This is the 10gen-supported Ruby driver for [MongoDB](http://www.mongodb.org).
Here's a quick code sample. See the MongoDB Ruby Tutorial
(http://www.mongodb.org/display/DOCS/Ruby+Tutorial) for much more:
Here's a quick code sample. See the [MongoDB Ruby Tutorial](http://www.mongodb.org/display/DOCS/Ruby+Tutorial)
for much more:
require 'rubygems'
require 'mongo'
include Mongo
require 'rubygems'
require 'mongo'
include Mongo
db = Connection.new.db('sample-db')
coll = db.collection('test')
db = Connection.new.db('sample-db')
coll = db.collection('test')
coll.remove
3.times do |i|
coll.insert({'a' => i+1})
end
puts "There are #{coll.count()} records. Here they are:"
coll.find().each { |doc| puts doc.inspect }
coll.remove
3.times do |i|
coll.insert({'a' => i+1})
end
puts "There are #{coll.count()} records. Here they are:"
coll.find().each { |doc| puts doc.inspect }
# Installation
= Installation
=== Ruby Versions
### Ruby Versions
The driver works and is consistently tested on Ruby 1.8.6, 1.8.7, and 1.9.2, and JRuby 1.5.1.
Note that if you're on 1.8.7, be sure that you're using a patchlevel >= 249. There
are some IO bugs in earlier versions.
=== Gems
### Gems
The driver's gems are hosted at Rubygems.org[http://rubygems.org]. Make sure you're
The driver's gems are hosted at [Rubygems.org](http://rubygems.org). Make sure you're
using the latest version of rubygems:
$ gem update --system
$ gem update --system
Then you can install the mongo gem as follows:
$ gem install mongo
$ gem install mongo
The driver also requires the bson gem:
$ gem install bson
$ gem install bson
And for a significant performance boost, you'll want to install the C extensions:
$ gem install bson_ext
$ gem install bson_ext
Note that bson_ext isn't used with JRuby. Instead, some native Java extensions are bundled with the bson gem.
If you ever need to modify these extenions, you can recompile with the following rake task:
$ rake build:java
$ rake build:java
=== From the GitHub source
### From the GitHub source
The source code is available at http://github.com/mongodb/mongo-ruby-driver.
You can either clone the git repository or download a tarball or zip file.
Once you have the source, you can use it from wherever you downloaded it or
you can install it as a gem from the source by typing
$ rake gem:install
$ rake gem:install
To install the C extensions from source, type this instead:
$ rake gem:install_extensions
$ rake gem:install_extensions
That's all there is to it!
= Examples
# Examples
For extensive examples, see the MongoDB Ruby Tutorial
(http://www.mongodb.org/display/DOCS/Ruby+Tutorial).
For extensive examples, see the [MongoDB Ruby Tutorial](http://www.mongodb.org/display/DOCS/Ruby+Tutorial).
Bundled with the driver are many examples, located in the "examples" subdirectory. Samples include using
the driver and using the GridFS class GridStore. MongoDB must be running for
@ -80,18 +77,15 @@ these examples to work, of course.
Here's how to start MongoDB and run the "simple.rb" example:
$ cd path/to/mongo
$ ./mongod run
... then in another window ...
$ cd path/to/mongo-ruby-driver
$ ruby examples/simple.rb
$ cd path/to/mongo
$ ./mongod run
... then in another window ...
$ cd path/to/mongo-ruby-driver
$ ruby examples/simple.rb
See also the test code, especially test/test_db_api.rb.
= GridFS
Note: The GridStore class has been deprecated. Use either the Grid or GridFileSystem
classes to take advantage of GridFS.
# GridFS
The Ruby driver include two abstractions for storing large files: Grid and GridFileSystem.
The Grid class is a Ruby implementation of MongoDB's GridFS file storage
@ -103,87 +97,56 @@ for details, and see examples/gridfs.rb for code that uses many of the Grid
features (metadata, content type, seek, tell, etc).
Examples:
include Mongo
# Write a file on disk to the Grid
file = File.open('image.jpg')
grid = Grid.new(db)
id = grid.put(file)
# Get a database
db = Mongo::Connection.new.db('app-db')
# Retrieve the file
file = grid.get(id)
file.read
# GridFileSystem. Store the text "Hello, world!" in the fs.
fs = GridFileSystem.new(db)
fs.open('filename', 'w') do |f|
f.write "Hello, world!"
end
# Get all the file's metata
file.filename
file.content_type
file.metadata
# GridFileSystem. Output "Hello, world!"
fs = GridFileSystem.new(db)
fs.open('filename', 'r') do |f|
puts f.read
end
# Notes
# Write a file on disk to the Grid
file = File.open('image.jpg')
grid = Grid.new(db)
id = grid.put(file)
# Retrieve the file
file = grid.get(id)
file.read
# Get all the file's metata
file.filename
file.content_type
file.metadata
= Notes
== Thread Safety
## Thread Safety
The driver is thread-safe.
== Connection Pooling
## Connection Pooling
As of 0.18, the driver implements connection pooling. By default, only one
As of v0.18, the driver implements connection pooling. By default, only one
socket connection will be opened to MongoDB. However, if you're running a
multi-threaded application, you can specify a maximum pool size and a maximum
timeout for waiting for old connections to be released to the pool.
To set up a pooled connection to a single MongoDB instance:
@conn = Connection.new("localhost", 27017, :pool_size => 5, :timeout => 5)
A pooled connection to a paired instance would look like this:
@conn = Connection.new({:left => ["db1.example.com", 27017],
:right => ["db2.example.com", 27017]}, nil,
:pool_size => 20, :timeout => 5)
@conn = Connection.new("localhost", 27017, :pool_size => 5, :timeout => 5)
Though the pooling architecture will undoubtedly evolve, it currently owes much credit
to the connection pooling implementations in ActiveRecord and PyMongo.
== Using with Phusion Passenger
## Using with Phusion Passenger and Unicorn
When passenger is in smart spawning mode you need to be sure that child
processes forked by passenger will create a new connection to the database.
activerecord-mongo-adapter handles this for you, so if you are using that
you shouldn't need to worry about it. Otherwise you'll either need to use
conservative spawning[http://www.modrails.org/documentation/Users%20guide.html#RailsSpawnMethod]
or handle reconnecting when passenger forks a new process:
When Passenger and Unicorn are in smart spawning mode you need to be sure that child
processes will create a new connection to the database. In Passenger, this can be handled like so:
if defined?(PhusionPassenger)
PhusionPassenger.on_event(:starting_worker_process) do |forked|
if forked
# Call db.connect to reconnect here
if defined?(PhusionPassenger)
PhusionPassenger.on_event(:starting_worker_process) do |forked|
if forked
# Create new connection here
end
end
end
end
The above code should be put in _environment.rb_ or in an initialization
script.
The above code should be put into a Rails initializer or other initialization script.
See this thread[http://groups.google.com/group/mongodb-user/browse_thread/thread/f31e2d23de38136a]
for more details on this issue.
== String Encoding
## String Encoding
The BSON ("Binary JSON") format used to communicate with Mongo requires that
strings be UTF-8 (http://en.wikipedia.org/wiki/UTF-8).
@ -193,18 +156,18 @@ and received from Mongo are converted to UTF-8 when necessary, and strings
read from Mongo will have their character encodings set to UTF-8.
When used with Ruby 1.8, the bytes in each string are written to and read from
Mongo as-is. If the string is ASCII all is well, because ASCII is a subset of
Mongo as is. If the string is ASCII, all is well, because ASCII is a subset of
UTF-8. If the string is not ASCII, it may not be a well-formed UTF-8
string.
== Primary Keys
## Primary Keys
The field _id is a primary key. It is treated specially by the database, and
The `_id` field is a primary key. It is treated specially by the database, and
its use makes many operations more efficient. The value of an _id may be of
any type. The database itself inserts an _id value if none is specified when
a record is inserted.
=== Primary Key Factories
### Primary Key Factories
A primary key factory is a class you supply to a DB object that knows how to
generate _id values. If you want to control _id values or even their types,
@ -213,7 +176,7 @@ using a PK factory lets you do so.
You can tell the Ruby Mongo driver how to create primary keys by passing in
the :pk option to the Connection#db method.
db = Mongo::Connection.new.db('dbname', :pk => MyPKFactory.new)
db = Mongo::Connection.new.db('dbname', :pk => MyPKFactory.new)
A primary key factory object must respond to :create_pk, which should
take a hash and return a hash which merges the original hash with any
@ -227,12 +190,12 @@ returned will be inserted.
Here is a sample primary key factory, taken from the tests:
class TestPKFactory
def create_pk(row)
row['_id'] ||= Mongo::ObjectID.new
row
class TestPKFactory
def create_pk(row)
row['_id'] ||= Mongo::ObjectID.new
row
end
end
end
Here's a slightly more sophisticated one that handles both symbol and string
keys. This is the PKFactory that comes with the MongoRecord code (an
@ -254,13 +217,9 @@ changeable at all is so that libraries such as MongoRecord that use this
driver can set the PK factory after obtaining the database but before using it
for the first time.
== The DB Class
## The DB Class
=== Primary Key factories
See the section on "Primary Keys" above.
=== Strict mode
### Strict mode
Each database has an optional strict mode. If strict mode is on, then asking
for a collection that does not exist will raise an error, as will asking to
@ -268,90 +227,85 @@ create a collection that already exists. Note that both these operations are
completely harmless; strict mode is a programmer convenience only.
To turn on strict mode, either pass in :strict => true when obtaining a DB
object or call the :strict= method:
object or call the `:strict=` method:
db = Connection.new.db('dbname', :strict => true)
# I'm feeling lax
db.strict = false
# No, I'm not!
db.strict = true
db = Connection.new.db('dbname', :strict => true)
# I'm feeling lax
db.strict = false
# No, I'm not!
db.strict = true
The method DB#strict? returns the current value of that flag.
== Cursors
## Cursors
Random cursor fun facts:
Notes:
- Cursors are enumerable.
* Cursors are enumerable (and have a #to_a method).
- The query doesn't get run until you actually attempt to retrieve data from a
* The query doesn't get run until you actually attempt to retrieve data from a
cursor.
- Cursors have a to_a method.
* Cursors will timeout on the server after 10 minutes. If you need to keep a cursor
open for more than 10 minutes, specify `:timeout => false` when you create the cursor.
= Testing
# Testing
If you have the source code, you can run the tests. There's a separate rake task for testing with
the bson_ext C extension enabled.
If you have the source code, you can run the tests.
$ rake test:c
$ rake test:c
If you want to test the basic Ruby encoder, or if you're running JRuby:
If you want to test the basic Ruby encoder, without the C extension, or if you're running JRuby:
$ rake test:ruby
$ rake test:ruby
These will run both unit and functional tests. To run these tests alone:
$ rake test:unit
$ rake test:functional
$ rake test:unit
$ rake test:functional
To run any individual rake tasks with the C extension enabled, just pass C_EXT=true to the task:
$ rake test:unit C_EXT=true
$ rake test:unit C_EXT=true
If you want to test replica pairs, you can run the following tests
If you want to test replica set, you can run the following tests
individually:
$ rake test:pair_count
$ rake test:pair_insert
$ rake test:pair_query
$ rake test:replica_set_count
$ rake test:replica_set_insert
$ rake test:replica_set_query
It's also possible to test replica pairs with connection pooling:
$ rake test:pooled_pair_insert
===Shoulda and Mocha
### Shoulda and Mocha
Running the test suite requires shoulda and mocha. You can install them as follows:
$ gem install shoulda
$ gem install mocha
$ gem install shoulda
$ gem install mocha
The tests assume that the Mongo database is running on the default port. You
can override the default host (localhost) and port (Connection::DEFAULT_PORT) by
using the environment variables MONGO_RUBY_DRIVER_HOST and
MONGO_RUBY_DRIVER_PORT.
= Documentation
# Documentation
This documentation is available online at http://api.mongodb.org/ruby. You can
This documentation is available online at [http://api.mongodb.org/ruby](http://api.mongodb.org/ruby). You can
generate the documentation if you have the source by typing
$ rake ydoc
$ rake ydoc
Then open the file +ydoc/index.html+.
= Release Notes
# Release Notes
See HISTORY.
= Credits
# Credits
See CREDITS.
= License
# License
Copyright 2008-2010 10gen Inc.

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@ -11,7 +11,7 @@ Gem::Specification.new do |s|
s.require_paths = ['lib']
s.files = ['README.rdoc', 'HISTORY', 'Rakefile',
s.files = ['README.md', 'HISTORY', 'Rakefile',
'mongo.gemspec', 'LICENSE.txt']
s.files += ['lib/mongo.rb'] + Dir['lib/mongo/**/*.rb']
s.files += Dir['examples/**/*.rb'] + Dir['bin/**/*.rb']
@ -25,8 +25,8 @@ Gem::Specification.new do |s|
s.test_files -= Dir['test/mongo_bson/*.rb'] # remove these files from the manifest
s.has_rdoc = true
s.rdoc_options = ['--main', 'README.rdoc', '--inline-source']
s.extra_rdoc_files = ['README.rdoc']
s.rdoc_options = ['--main', 'README.md', '--inline-source']
s.extra_rdoc_files = ['README.md']
s.authors = ['Jim Menard', 'Mike Dirolf', 'Kyle Banker']
s.email = 'mongodb-dev@googlegroups.com'