This document discusses building bibliographies in Drupal using entity references and views. It recommends creating separate content types for citations and citation authors, then using an entity reference field to link the citation to its author(s). Views relationships and contextual filters allow filtering and displaying related entities. Contextual filters retrieve filter terms from the URL, while relationships expand queries to include related objects like a node's author or a file's attached node.

1. Building a Bibliography
Via Entity References and Views
Thursday, June 27, 13

2. Bio
Eric Aitala
Earth and Space Science
Partnership - College of
Earth & Mineral Science
ema13@psu.edu
@aitala
Drupal dev since 2006
Thursday, June 27, 13

3. Entities
Introduced in D7
An entity is a collection of information which is fieldable.
Examples
Node
Comments
Users
Taxonomy vocabulary & taxonomy term
File
Thursday, June 27, 13

4. Entities
Entity Type - Node, User, File
Bundle - Article, Basic Page
Field(s) - Body, text field, date field
Entity - A specific instance of an entity type or bundle
i.e. example.com/node/27
Stores data (properties) in the database.
Fields provide additional properties to extend the default
bundle(s).
Thursday, June 27, 13

5. Entities
More information at:
https://drupal.org/node/1261744
http://www.slideshare.net/jdleonard/entities-in-drupal-7-
the-entity-api
Thursday, June 27, 13

6. Citation Example
A publication
Contains a title,
author(s), an abstract,
a publication date, etc.
Why not use Biblio
module? Its wonky...
Create a content type
for it....
Thursday, June 27, 13

7. Author Field
The author field can be
quite complicated...
Thursday, June 27, 13

8. Author Field
If I was in a hurry...
Plain text field
Infinite instances
Thursday, June 27, 13

9. But.....
... you may not get
what you expect.
I’ve done this once....
... bad idea.
Thursday, June 27, 13

10. There is a better way...
Thursday, June 27, 13

11. Entity Reference
Entity reference module
https://drupal.org/project/entityreference
It provides a field which allows one entity to refer to
another... aka, a specific node can point, via a link for
example, to another node.
Integrates with Views, Feeds, and Migrate module
Thursday, June 27, 13

12. Citation Example, v2
Instead of having a plain text field, create two content
types
Citation
Title, abstract, etc.
Citation Author
Name, degrees, affiliation, etc.
Then have the Citation do an Entity Reference to the
Citation Author(s)
Thursday, June 27, 13

13. Citation Example, v2
Thursday, June 27, 13

14. Citation Example, v2
Add a field to the Citation type to the Citation Author
type.
Thursday, June 27, 13

15. Citation Example, v2
Thursday, June 27, 13

16. Citation Example, v2
In my real world case, I have the Citation type refer to
Citation Author type which in turn may refer to a User
entity!
Thursday, June 27, 13

17. Demo time....
Thursday, June 27, 13

18. Modules
Entity API
Functionality not included in D7 core
CRUD functionality, etc. (You really need this module!)
https://drupal.org/project/entity
Entity Reference
https://drupal.org/project/entityreference
Entity Reference Dynamic Select Widget
https://drupal.org/project/entityreference_dynamicselect_widget
References dialog - adds the create & edit inline links
https://drupal.org/project/references_dialog
Thursday, June 27, 13

19. Now... Views....?
How do we handle
things like entity
references in Views?
Under the Views
‘Advanced’ tab...
Contextual Filter
Relationships
Thursday, June 27, 13

20. Now... Views....?
Contextual Filter
“Contextual Filters (known in previous versions of
Views as "Arguments") are input. While they often
come from the URL, they don't always. Don't be
shocked when they don't. Each display type may
have its own source for contextual filters.”
Thursday, June 27, 13

21. Now... Views....?
Relationships
“Relationships allow you to expand the query to
include objects other than the base query.”
“The main example of the relationship that is there by
default is the node --> user relationship; every node
has an author, and if a node is in the query, the user
who wrote that node is automatically made
available.”
Thursday, June 27, 13

22. Now... Views....?
Relationships
“A similar relationship that is not automatically made
available is for node revisions. Each revision has its
own author, which is the user who made the revision.
By adding the "Node revision: User" relationship, all
of the 'user' fields, sorts, filters and arguments
available to a user will now be available for the
revision author.”
Thursday, June 27, 13

23. What does that mean?
Contextual Filter
Has query/filter terms in the URL (usually)
http://example.com/events/2013/6/25
Relationships
Exploit a default relationship - node and node author
Create a relationship between entities - a file and the
node it is attached to, or vice versa
Thursday, June 27, 13

24. Demo time....
Thursday, June 27, 13