class BSON::Document
This module provides behaviour for serializing and deserializing entire BSON documents, according to the BSON specification.
@note The specification is: document ::= int32 e_list “x00”
@see bsonspec.org/#/specification
@since 2.0.0
Public Class Methods
Instantiate a new Document. Valid parameters for instantiation is a hash only or nothing.
@example Create the new Document.
BSON::Document.new(name: "Joe", age: 33)
@param [ Hash ] elements The elements of the document.
@since 3.0.0
# File lib/bson/document.rb, line 169 def initialize(elements = nil) super() (elements || {}).each_pair{ |key, value| self[key] = value } end
Public Instance Methods
Get a value from the document for the provided key. Can use string or symbol access, with string access being the faster of the two.
@example Get an element for the key.
document["field"]
@example Get an element for the key by symbol.
document[:field]
@param [ String, Symbol ] key The key to look up.
@return [ Object ] The found value, or nil if none found.
@since 2.0.0
# File lib/bson/document.rb, line 87 def [](key) super(convert_key(key)) end
Set a value on the document. Will normalize symbol keys into strings.
@example Set a value on the document.
document[:test] = "value"
@param [ String, Symbol ] key The key to update. @param [ Object ] value The value to update.
@return [ Object ] The updated value.
@since 3.0.0
# File lib/bson/document.rb, line 102 def []=(key, value) super(convert_key(key), convert_value(value)) end
Deletes the key-value pair and returns the value from the document whose key is equal to key. If the key is not found, returns the default value. If the optional code block is given and the key is not found, pass in the key and return the result of block.
@example Delete a key-value pair
document.delete(:test)
@param [ Object ] key The key of the key-value pair to delete.
@return [ Object ]
@since 4.0.0
# File lib/bson/document.rb, line 156 def delete(key, &block) super(convert_key(key), &block) end
Retrieves the value object corresponding to the each key objects repeatedly. Will normalize symbol keys into strings.
@example Get value from nested sub-documents, handling missing levels.
document # => { :key1 => { "key2" => "value"}} document.dig(:key1, :key2) # => "value" document.dig("key1", "key2") # => "value" document.dig("foo", "key2") # => nil
@param [ Array<String, Symbol> ] *keys Keys, which constitute a “path” to the nested value.
@return [ Object, NilClass ] The requested value or nil.
@since 3.0.0
# File lib/bson/document.rb, line 225 def dig(*keys) super(*keys.map{|key| convert_key(key)}) end
Get a value from the document for the provided key. Can use string or symbol access, with string access being the faster of the two.
@overload fetch(key)
Returns a value from the hash for the given key. If the key does not exist, raises KeyError exception.
@overload fetch(key, default)
Returns a value from the hash for the given key. If the key does not exist, returns *default*.
@overload fetch(key, &block)
Returns a value from the hash for the given key. If the key does not exist, returns the value of the block called with the key.
@example Get an element for the key.
document.fetch("field")
@example Get an element for the key by symbol with a default.
document.fetch(:field, 'foo')
@example Get an element for the key by symbol with a block default.
document.fetch(:field) { |key| key.upcase }
@param [ String, Symbol ] key The key to look up. @param [ Object ] default Returned value if key does not exist. @yield [key] Block returning default value for the given key.
@return [ Object ] The found value. Raises KeyError if none found.
@since 4.4.0
# File lib/bson/document.rb, line 68 def fetch(key, *args, &block) key = convert_key(key) super(key, *args, &block) end
Returns true if the given key is present in the document. Will normalize symbol keys into strings.
@example Test if a key exists using a symbol
document.has_key?(:test)
@param [ Object ] key The key to check for.
@return [ true, false]
@since 4.0.0
# File lib/bson/document.rb, line 117 def has_key?(key) super(convert_key(key)) end
Returns true if the given value is present in the document. Will normalize symbols into strings.
@example Test if a key exists using a symbol
document.has_value?(:test)
@param [ Object ] value THe value to check for.
@return [ true, false]
@since 4.0.0
# File lib/bson/document.rb, line 136 def has_value?(value) super(convert_value(value)) end
Merge this document with another document, returning a new document in the process.
@example Merge with another document.
document.merge(name: "Bob")
@param [ BSON::Document, Hash ] other The document/hash to merge with.
@return [ BSON::Document ] The result of the merge.
@since 3.0.0
# File lib/bson/document.rb, line 185 def merge(other, &block) dup.merge!(other, &block) end
Merge this document with another document, returning the same document in the process.
@example Merge with another document.
document.merge(name: "Bob")
@param [ BSON::Document, Hash ] other The document/hash to merge with.
@return [ BSON::Document ] The result of the merge.
@since 3.0.0
# File lib/bson/document.rb, line 200 def merge!(other) other.each_pair do |key, value| value = yield(convert_key(key), self[key], convert_value(value)) if block_given? && self[key] self[key] = value end self end
Slices a document to include only the given keys. Will normalize symbol keys into strings. (this method is backported from ActiveSupport::Hash)
@example Get a document/hash with only the `name` and `age` fields present
document # => { _id: <ObjectId>, :name => 'John', :age => 30, :location => 'Earth' } document.slice(:name, 'age') # => { name: 'John', age: 30 } document.slice('name') # => { name: 'John' } document.slice(:foo) # => nil
@param [ Array<String, Symbol> ] *keys Keys, that will be kept in the resulting document
@return [ BSON::Document ] The document with only the selected keys
@since 4.3.1
# File lib/bson/document.rb, line 246 def slice(*keys) super(*keys.map{|key| convert_key(key)}) end
Private Instance Methods
# File lib/bson/document.rb, line 253 def convert_key(key) key.to_bson_normalized_key end
# File lib/bson/document.rb, line 257 def convert_value(value) value.to_bson_normalized_value end