Module: ActiveFedora::Model::ClassMethods

Defined in:
lib/active_fedora/model.rb

Overview

Class Methods

These methods are mixed into the inheriting class.

Accessor and mutator methods are dynamically generated based on the contents of the @@field_spec hash, which stores the field specifications recorded during invocation of has_metadata.

Each metadata field will generate 3 methods:

fieldname_values
  *returns the current values array for this field
fieldname_values=(val) 
  *store val as the values array. val 
  may be a single string, or an array of strings 
  (single items become single element arrays).
fieldname_append(val)
  *appends val to the values array.

Instance Method Summary collapse

Instance Method Details

#attribute_get(name) ⇒ Object

wrapper around instance_variable_get, returns current value of @name



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# File 'lib/active_fedora/model.rb', line 269

def attribute_get(name)
  instance_variable_get("@#{name}")
end

#attribute_set(name, value) ⇒ Object

wrapper around instance_variable_set, sets @name to value



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# File 'lib/active_fedora/model.rb', line 264

def attribute_set(name, value)
  instance_variable_set("@#{name}", value)
end

#class_fields ⇒ Object 



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# File 'lib/active_fedora/model.rb', line 254

def class_fields
  #create dummy object that is empty by passing in fake pid
  object = self.new()#{:pid=>'FAKE'})
  fields = object.fields
  #reset id to nothing
  fields[:id][:values] = []
  return fields
end

#count(args = {}) ⇒ Object

Get a count of the number of objects from solr Takes :conditions as an argument



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# File 'lib/active_fedora/model.rb', line 135

def count(args = {})
    escaped_class_uri = SolrService.escape_uri_for_query(self.to_class_uri)
    q = "#{ActiveFedora::SolrService.solr_name(:has_model, :symbol)}:#{escaped_class_uri}"
    q << " AND #{args[:conditions]}" if args[:conditions]
    SolrService.query(q, :raw=>true, :rows=>0)['response']['numFound']
end

#exists?(pid) ⇒ Boolean

Returns true if the pid exists in the repository @param pid @return

Returns:

  • (Boolean) 


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# File 'lib/active_fedora/model.rb', line 122

def exists?(pid)
  inner = DigitalObject.find(self, pid)
  !inner.new?
end

#find(args, opts = {}) ⇒ Object

Returns an Array of objects of the Class that find is being called on

@param either a pid or :all

Parameters:

  • opts (Hash) (defaults to: {}) —

    the options to create a message with.

Options Hash (opts):

  • :rows (Integer) —

    when :all is passed, the maximum number of rows to load from solr

  • :cast (Boolean) —

    when true, examine the model and cast it to the first known cModel



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# File 'lib/active_fedora/model.rb', line 104

def find(args, opts={})
  opts = {:rows=>25}.merge(opts)
  if args == :all
    escaped_class_uri = SolrService.escape_uri_for_query(self.to_class_uri)
    q = "#{ActiveFedora::SolrService.solr_name(:has_model, :symbol)}:#{escaped_class_uri}"
    hits = SolrService.query(q, :rows=>opts[:rows]) 
    return hits.map do |hit|
       pid = hit[SOLR_DOCUMENT_ID]
       find_one(pid, opts[:cast])
    end
  elsif args.class == String
    return find_one(args, opts[:cast])
  end
end

#find_by_fields_by_solr(query_fields, opts = {}) ⇒ Object

Find all ActiveFedora objects for this model that match arguments passed in by querying Solr. Like find_by_solr this returns a solr result.

query_fields a hash of object field names and values to filter on (query_fields must be the solr_field_name for non-MetadataDatastream derived datastreams) opts specifies options for the solr query

options may include:

:sort             => array of hash with one hash per sort by field... defaults to [{system_create=>:descending}]
:default_field, :rows, :filter_queries, :debug_query,
:explain_other, :facets, :highlighting, :mlt,
:operator         => :or / :and
:start            => defaults to 0
:field_list       => array, defaults to ["*", "score"]



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# File 'lib/active_fedora/model.rb', line 183

def find_by_fields_by_solr(query_fields,opts={})
  ActiveSupport::Deprecation.warn("find_by_fields_by_solr is deprecated and will be removed in the next release")
  #create solr_args from fields passed in, needs to be comma separated list of form field1=value1,field2=value2,...
  escaped_class_name = self.name.gsub(/(:)/, '\\:')
  query = "#{ActiveFedora::SolrService.solr_name(:active_fedora_model, :symbol)}:#{escaped_class_name}" 
  
  query_fields.each_pair do |key,value|
    unless value.nil?
      solr_key = key
      #convert to symbol if need be
      key = key.to_sym if !class_fields.has_key?(key)&&class_fields.has_key?(key.to_sym)
      #do necessary mapping with suffix in most cases, otherwise ignore as a solr field key that activefedora does not know about
      if class_fields.has_key?(key) && class_fields[key].has_key?(:type)
        type = class_fields[key][:type]
        type = :string unless type.kind_of?(Symbol)
        solr_key = ActiveFedora::SolrService.solr_name(key,type)
      end
      
      escaped_value = value.gsub(/(:)/, '\\:')
      #escaped_value = escaped_value.gsub(/ /, '\\ ')
      key = SOLR_DOCUMENT_ID if (key === :id || key === :pid)
      query = key.to_s.eql?(SOLR_DOCUMENT_ID) ? "#{query} AND #{key}:#{escaped_value}" : "#{query} AND #{solr_key}:#{escaped_value}"  
    end
  end

  query_opts = {}
  opts.each do |key,value|
    key = key.to_sym
    query_opts[key] = value
  end

  #set default sort to created date ascending
  unless query_opts.include?(:sort)
    query_opts.merge!({:sort=>[ActiveFedora::SolrService.solr_name(:system_create,:date)+' asc']}) 
  else
    #need to convert to solr names for all fields
    sort_array =[]
  
    opts[:sort].collect do |sort|
      sort_direction = 'ascending'
      if sort.respond_to?(:keys)
        key = sort.keys[0]
        sort_direction = sort[key]
      else
        key = sort.to_s
      end
      sort_direction = sort_direction =~ /^desc/ ? 'desc' : 'asc'
      field_name = key
      
      if key.to_s =~ /^system_create/
        field_name = :system_create_date
        key = :system_create
      elsif key.to_s =~ /^system_mod/  
        field_name = :system_modified_date
        key = :system_modified
      end
   
      solr_name = field_name 
      if class_fields.include?(field_name.to_sym)
        solr_name = ActiveFedora::SolrService.solr_name(key,class_fields[field_name.to_sym][:type])
      end
      sort_array.push("#{solr_name} #{sort_direction}")
    end
  
    query_opts[:sort] = sort_array.join(",")
  end

  logger.debug "Querying solr for #{self.name} objects with query: '#{query}'"
  SolrService.query(query, query_opts) 
end

#find_by_solr(query, args = {}) ⇒ Object

If query is :all, this method will query Solr for all instances

of self.type (based on active_fedora_model_s as indexed
by Solr). If the query is any other string, this method simply does
a pid based search (id:query). 

Note that this method does _not_ return ActiveFedora::Model 
objects, but rather an array of SolrResults.

Args is an options hash, which is passed into the SolrService 
connection instance.



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# File 'lib/active_fedora/model.rb', line 158

def find_by_solr(query, args={})
  if query == :all
    escaped_class_name = self.name.gsub(/(:)/, '\\:')
    SolrService.query("#{ActiveFedora::SolrService.solr_name(:active_fedora_model, :symbol)}:#{escaped_class_name}", args) 
  elsif query.class == String
    escaped_id = query.gsub(/(:)/, '\\:')          
    SolrService.query("#{SOLR_DOCUMENT_ID}:#{escaped_id}", args) 
  end
end

#find_model(pid) ⇒ Object 



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# File 'lib/active_fedora/model.rb', line 127

def find_model(pid)
  ActiveSupport::Deprecation.warn("find_model is deprecated.  Use find instead")
  find(pid)
end

#load_instance(pid) ⇒ Object

Retrieve the Fedora object with the given pid and deserialize it as an instance of the current model Note that you can actually pass a pid into this method, regardless of Fedora model type, and ActiveFedora will try to parse the results into the current type of self, which may or may not be what you want.

Examples:

this will return an instance of Book, even if the object hydra:dataset1 asserts that it is a Dataset

Book.load_instance("hydra:dataset1")

Parameters:

  • pid (String) —

    of the object to load



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# File 'lib/active_fedora/model.rb', line 74

def load_instance(pid)
  ActiveSupport::Deprecation.warn("load_instance is deprecated.  Use find instead")
  find(pid)
end

#solr_search(query, args = {}) ⇒ Object

Sends a query directly to SolrService



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# File 'lib/active_fedora/model.rb', line 143

def solr_search(query, args={})
  SolrService.instance.conn.query(query, args)
end

#to_class_uri(attrs = {}) ⇒ Object

Returns a suitable uri object for :has_model Should reverse Model#from_class_uri



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# File 'lib/active_fedora/model.rb', line 83

def to_class_uri(attrs = {})
  unless self.respond_to? :pid_suffix
    pid_suffix = attrs.has_key?(:pid_suffix) ? attrs[:pid_suffix] : ContentModel::CMODEL_PID_SUFFIX
  else
    pid_suffix = self.pid_suffix
  end
  unless self.respond_to? :pid_namespace
    namespace = attrs.has_key?(:namespace) ? attrs[:namespace] : ContentModel::CMODEL_NAMESPACE   
  else
    namespace = self.pid_namespace
  end
  "info:fedora/#{namespace}:#{ContentModel.sanitized_class_name(self)}#{pid_suffix}" 
end