class AWS::Core::Policy

@return [String] A unique ID for the policy.

@see Statement @return [Array] An array of policy statements.

@return [String] The version of the policy language used in this

policy object.

Constructs a policy from a JSON representation. @see initialize @return [Policy] Returns a Policy object constructed by parsing

the passed JSON policy.

# File lib/aws/core/policy.rb, line 146
def self.from_json(json)
  new(JSON.parse(json))
end

Constructs a policy. There are a few different ways to build a policy:

• With hash arguments:

  Policy.new(:statements => [
    { :effect => :allow,
      :actions => :all,
      :principals => ["abc123"],
      :resources => "mybucket/mykey" 
    }
  ])
  

• From a JSON policy document:

  Policy.from_json(policy_json_string)

• With a block:

  Policy.new do |policy|
  
    policy.allow(
      :actions => ['s3:PutObject'],
      :resources => "arn:aws:s3:::mybucket/mykey/*",
      :principals => :any
    ).where(:acl).is("public-read")
  
  end
  

# File lib/aws/core/policy.rb, line 77
def initialize(opts = {})
  @statements = opts.values_at(:statements, "Statement").select do |a|
    a.kind_of?(Array)
  end.flatten.map do |stmt|
    self.class::Statement.new(stmt)
  end
  
  if opts.has_key?(:id) or opts.has_key?("Id")
    @id = opts[:id] || opts["Id"]
  else
    @id = UUIDTools::UUID.timestamp_create.to_s.tr('-','')
  end
  if opts.has_key?(:version) or opts.has_key?("Version")
    @version = opts[:version] || opts["Version"]
  else
    @version = "2008-10-17"
  end
  
  yield(self) if block_given?
end

@return [Boolean] Returns true if the two policies are the same.

# File lib/aws/core/policy.rb, line 99
def ==(other)
  if other.kind_of?(Core::Policy)
    self.hash_without_ids == other.hash_without_ids
  else
    false
  end
end

Convenience method for constructing a new statement with the “Allow” effect and adding it to the policy. For example:

policy.allow(:actions => [:put_object],
             :principals => :any,
             :resources => "mybucket/mykey/*").
  where(:acl).is("public-read")

@option (see Statement#initialize) @see Statement#initialize @return [ConditionBuilder]

# File lib/aws/core/policy.rb, line 219
def allow(opts = {})
  stmt = self.class::Statement.new(opts.merge(:effect => :allow))
  statements << stmt
  ConditionBuilder.new(stmt.conditions)
end

Convenience method for constructing a new statement with the “Deny” effect and adding it to the policy. For example:

policy.deny(
  :actions => [:put_object],
  :principals => :any,
  :resources => "mybucket/mykey/*"
).where(:acl).is("public-read")

@param (see Statement#initialize) @see Statement#initialize @return [ConditionBuilder]

# File lib/aws/core/policy.rb, line 237
def deny(opts = {})
  stmt = self.class::Statement.new(opts.merge(:effect => :deny))
  statements << stmt
  ConditionBuilder.new(stmt.conditions)
end

Returns a hash representation of the policy. The following statements are equivalent:

policy.to_h.to_json
policy.to_json

@return [Hash]

# File lib/aws/core/policy.rb, line 129
def to_h
  { 
    "Version" => version,
    "Id" => id,
    "Statement" => statements.map { |st| st.to_h } 
  }
end

@return [String] a JSON representation of the policy.

# File lib/aws/core/policy.rb, line 138
def to_json
  to_h.to_json
end

Removes the ids from the policy and its statements for the purpose of comparing two policies for equivilence. @return [Hash] Returns the policy as a hash with no ids @private

# File lib/aws/core/policy.rb, line 112
def hash_without_ids
  hash = self.to_h
  hash.delete('Id')
  hash['Statement'].each do |statement|
    statement.delete('Sid')
  end
  hash
end