Document model – PRC Platform

This document provides a comprehensive overview of the document model and relationships between post types, meta fields, and taxonomies across the PRC-* plugins in the Pew Research Center WordPress platform.

Architecture Overview

The PRC Platform uses a modular plugin architecture where:

Post types define content entities (articles, staff, datasets, etc.)
Taxonomies provide classification and organization (topics, teams, formats)
Meta fields store additional structured data on posts
Term Data Store (TDS) pattern links post types to taxonomies for hybrid content

Visual Diagram

erDiagram
    %% ===========================================
    %% CORE CONTENT POST TYPES
    %% ===========================================

    POST {
        int ID PK
        string post_title
        text post_content
        string post_status
        datetime post_date
    }

    FEATURE {
        int ID PK
        string post_title
        text post_content
        string _feature_dev_notes
        array _feature_rewrites
    }

    QUIZ {
        int ID PK
        string post_title
        text post_content
        object _report
    }

    CHART {
        int ID PK
        string post_title
        text post_content
    }

    DATASET {
        int ID PK
        string post_title
        text post_content
        int _download_attachment_id
        int _total_downloads
        boolean is_atp
        string dataset_schema
    }

    COLLECTIONS {
        int ID PK
        string post_title
        text post_content
        string kicker_pattern_slug
    }

    %% ===========================================
    %% STAFF & BYLINES
    %% ===========================================

    STAFF {
        int ID PK
        string post_title
        text post_content
        string jobTitle
        string jobTitleExtended
        boolean bylineLinkEnabled
        object _maelstrom
        array socialProfiles
    }

    %% ===========================================
    %% UTILITY POST TYPES
    %% ===========================================

    HOMEPAGE {
        int ID PK
        string post_title
        text post_content
    }

    BLOCK_MODULE {
        int ID PK
        string post_title
        text post_content
        array _story_item_ids
    }

    NOTE {
        int ID PK
        string post_title
        text post_content
        array shared_with_users
    }

    DATA_TABLE {
        int ID PK
        string post_title
        text post_content
    }

    DOCUMENTATION {
        int ID PK
        string post_title
        text post_content
    }

    RELEASE_NOTE {
        int ID PK
        string post_title
        text post_content
    }

    RLS_TEMPLATE {
        int ID PK
        string post_title
        text post_content
    }

    %% ===========================================
    %% TAXONOMIES
    %% ===========================================

    CATEGORY {
        int term_id PK
        string name
        string slug
        int parent
    }

    RESEARCH_TEAMS {
        int term_id PK
        string name
        string slug
        int parent
    }

    FORMATS {
        int term_id PK
        string name
        string slug
    }

    BYLINES {
        int term_id PK
        string name
        string slug
        boolean is_guest_author
    }

    COLLECTION_TAX {
        int term_id PK
        string name
        string slug
        int parent
    }

    DATASETS_TAX {
        int term_id PK
        string name
        string slug
        int parent
    }

    REGIONS_COUNTRIES {
        int term_id PK
        string name
        string slug
        int parent
    }

    LANGUAGES {
        int term_id PK
        string name
        string slug
    }

    AREAS_OF_EXPERTISE {
        int term_id PK
        string name
        string slug
        int parent
    }

    STAFF_TYPE {
        int term_id PK
        string name
        string slug
        int parent
    }

    FUND_POOLS {
        int term_id PK
        string name
        string slug
        string funder_url
        string funder_id
        float _funder_budget
    }

    MODE_OF_ANALYSIS {
        int term_id PK
        string name
        string slug
    }

    POST_VISIBILITY {
        int term_id PK
        string name
        string slug
    }

    BLOCK_AREA {
        int term_id PK
        string name
        string slug
        int parent
    }

    LEVEL_OF_EFFORT {
        int term_id PK
        string name
        string slug
    }

    PRIMARY_AUDIENCE {
        int term_id PK
        string name
        string slug
    }

    INFORMATION_TYPE {
        int term_id PK
        string name
        string slug
    }

    DECODED_CATEGORY {
        int term_id PK
        string name
        string slug
    }

    %% ===========================================
    %% RELATIONSHIPS - Core Post Type
    %% ===========================================

    POST ||--o{ CATEGORY : "has topics"
    POST ||--o{ RESEARCH_TEAMS : "belongs to"
    POST ||--o{ FORMATS : "has format"
    POST ||--o{ BYLINES : "authored by"
    POST ||--o{ COLLECTION_TAX : "part of"
    POST ||--o{ DATASETS_TAX : "has dataset"
    POST ||--o{ REGIONS_COUNTRIES : "covers"
    POST ||--o{ LANGUAGES : "written in"
    POST ||--o{ POST_VISIBILITY : "visibility"

    %% ===========================================
    %% RELATIONSHIPS - Feature
    %% ===========================================

    FEATURE ||--o{ CATEGORY : "has topics"
    FEATURE ||--o{ RESEARCH_TEAMS : "belongs to"
    FEATURE ||--o{ BYLINES : "authored by"
    FEATURE ||--o{ DATASETS_TAX : "has dataset"
    FEATURE ||--o{ COLLECTION_TAX : "part of"
    FEATURE ||--o{ REGIONS_COUNTRIES : "covers"

    %% ===========================================
    %% RELATIONSHIPS - Quiz
    %% ===========================================

    QUIZ ||--o{ CATEGORY : "has topics"
    QUIZ ||--o{ RESEARCH_TEAMS : "belongs to"
    QUIZ ||--o{ BYLINES : "authored by"
    QUIZ ||--o{ DATASETS_TAX : "has dataset"
    QUIZ ||--o{ COLLECTION_TAX : "part of"
    QUIZ ||--o{ LEVEL_OF_EFFORT : "effort level"
    QUIZ ||--o{ PRIMARY_AUDIENCE : "audience"
    QUIZ ||--o{ INFORMATION_TYPE : "info type"

    %% ===========================================
    %% RELATIONSHIPS - Chart
    %% ===========================================

    CHART ||--o{ CATEGORY : "has topics"
    CHART ||--o{ DATASETS_TAX : "has dataset"

    %% ===========================================
    %% TERM DATA STORE RELATIONSHIPS
    %% (Post Type <-> Taxonomy Hybrid Pattern)
    %% ===========================================

    STAFF ||--|| BYLINES : "TDS linked"
    COLLECTIONS ||--|| COLLECTION_TAX : "TDS linked"
    DATASET ||--|| DATASETS_TAX : "TDS linked"

    %% ===========================================
    %% STAFF RELATIONSHIPS
    %% ===========================================

    STAFF ||--o{ AREAS_OF_EXPERTISE : "expertise in"
    STAFF ||--o{ STAFF_TYPE : "type of"
    STAFF ||--o{ RESEARCH_TEAMS : "member of"

    %% ===========================================
    %% COLLECTIONS RELATIONSHIPS
    %% ===========================================

    COLLECTIONS ||--o{ POST_VISIBILITY : "visibility"
    COLLECTIONS ||--o{ BYLINES : "curated by"

    %% ===========================================
    %% DATASET RELATIONSHIPS
    %% ===========================================

    DATASET }o--|| POST : "associated with"
    DATASET }o--|| FEATURE : "associated with"
    DATASET }o--|| CHART : "associated with"
    DATASET }o--|| QUIZ : "associated with"

    %% ===========================================
    %% BLOCK MODULE RELATIONSHIPS
    %% ===========================================

    BLOCK_MODULE ||--o{ BLOCK_AREA : "placed in"
    BLOCK_MODULE ||--o{ CATEGORY : "for topic"
    BLOCK_MODULE ||--o{ REGIONS_COUNTRIES : "for region"
    BLOCK_MODULE ||--o{ COLLECTION_TAX : "for collection"

    %% ===========================================
    %% DECODED RELATIONSHIPS
    %% ===========================================

    POST ||--o{ DECODED_CATEGORY : "decoded in"

Post Types Reference

Content Post Types

Post Type	Plugin	Description	Key Meta Fields
`post`	Core WP	Standard blog posts/articles	bylines, acknowledgements, displayBylines, reportMaterials, multiSectionReport
`feature`	prc-interactive-features	Interactive data visualizations	`_feature_rewrites`, `_feature_dev_notes`
`quiz`	prc-quiz-builder	Interactive quizzes	`_report`
`chart`	prc-chart-builder	Data visualizations/charts	–
`dataset`	prc-datasets	Downloadable datasets	`_download_attachment_id`, `_total_downloads`, `is_atp`, `dataset_schema`
`collections`	prc-collections	Curated content collections	`kicker_pattern_slug`
`rls_template`	prc-religious-landscape-study	RLS page templates	–

Staff & Bylines

Post Type	Plugin	Description	Key Meta Fields
`staff`	prc-staff-bylines	Staff member profiles	`jobTitle`, `jobTitleExtended`, `bylineLinkEnabled`, `_maelstrom`, `socialProfiles`

Utility Post Types

Post Type	Plugin	Description	Key Meta Fields
`homepage`	prc-homepages	Homepage layouts	–
`block_module`	prc-block-area-modules	Reusable block modules	`_story_item_ids`
`note`	prc-notes	Internal editorial notes	`shared_with_users`
`documentation`	prc-wiki	Platform documentation	–
`release-note`	prc-wiki	Release notes	–

Post-Like Types (via prc-post-like-types)

These post types use date-based permalinks like standard posts:

short-read
fact-sheet
decoded
press-release
stub

Default taxonomies: category, collection, formats, languages, research-teams

Page-Like Types (via prc-page-like-types)

These post types behave like pages with hierarchical URLs.

Default taxonomies: category, collection, formats, languages, research-teams

Taxonomies Reference

Core Classification Taxonomies

Taxonomy	Plugin	Description	Post Types
`category`	prc-platform-core	Topics (renamed from "Categories")	post, feature, quiz, chart, block_module, and post-like types
`research-teams`	prc-platform-core	Research teams (primary for permalinks)	post, feature, quiz, staff, dataset, fact-sheet, etc.
`formats`	prc-platform-core	Content formats	post, short-read, fact-sheet, feature, quiz, decoded, dataset, etc.
`regions-countries`	prc-platform-core	Geographic coverage	post, feature, fact-sheet, short-read, quiz, block_module
`languages`	prc-platform-core	Content language	post, fact-sheet, stub, decoded, short-read
`mode-of-analysis`	prc-platform-core	Research methodology	Various research post types
`fund-pools`	prc-platform-core	Funding sources	Various post types
`decoded-category`	prc-platform-core	Decoded blog categories	decoded

Linked Taxonomies (Term Data Store Pattern)

Taxonomy	Post Type	Plugin	Description
`bylines`	`staff`	prc-staff-bylines	Links staff profiles to byline terms
`collection`	`collections`	prc-collections	Links collection posts to collection terms
`datasets`	`dataset`	prc-datasets	Links dataset posts to dataset terms

Staff-Specific Taxonomies

Taxonomy	Plugin	Description
`areas-of-expertise`	prc-staff-bylines	Staff expertise areas
`staff-type`	prc-staff-bylines	Staff classification (staff, executive-team, managing-directors, former)

Utility Taxonomies

Taxonomy	Plugin	Description
`_post_visibility`	prc-platform-core	Controls post visibility (hidden-on-index, hidden-on-search)
`block_area`	prc-block-area-modules	Block module placement areas

Lookbook Taxonomies

Taxonomy	Plugin	Description
`level_of_effort`	prc-lookbook	Project effort classification
`primary_audience`	prc-lookbook	Target audience
`information_type`	prc-lookbook	Content information type

Key Patterns & Relationships

Term Data Store (TDS) Pattern

The TDS pattern creates a one-to-one relationship between a post type and a taxonomy term, enabling hybrid content where:

The post stores rich content (editor blocks, meta fields)
The term provides taxonomy relationships to other content

staff (post) <--TDS--> bylines (taxonomy)
collections (post) <--TDS--> collection (taxonomy)
dataset (post) <--TDS--> datasets (taxonomy)

This allows posts to be attached to the taxonomy term automatically, and the term archive acts as the public URL.

Plugin Opt-In System

Plugins opt their post types into features using the WordPress native post_type_supports() pattern via the supports array in register_post_type():

// Register a post type with feature supports
register_post_type( 'my-post-type', array(
    'supports' => array(
        'title',
        'editor',
        'thumbnail',
        // PRC Platform feature supports
        'prc-schema-seo',      // SEO meta fields and schema.org output
        'prc-bylines',         // Staff bylines and acknowledgements
        'prc-art-direction',   // Art direction image slots
        'prc-sitemap',         // Include in XML sitemap
        'prc-related-posts',   // Related posts functionality
        'prc-datasets',        // Datasets taxonomy attachment
        'prc-collections',     // Collections taxonomy attachment
        'prc-publish-workflows', // Watchers + publish-pipeline REST/meta on this CPT
    ),
    // ... other args
));

You can also add support after registration using add_post_type_support():

// Add support after registration
add_action( 'init', function() {
    add_post_type_support( 'my-post-type', 'prc-bylines' );
    add_post_type_support( 'my-post-type', 'prc-art-direction' );
}, 5 );

For publication listing and the main RSS feed, declare post type support (see prc-publication-listing):

add_post_type_support( 'my-post-type', 'prc-publication-listing' );

That opts the type into publication listing queries and into the main site feed. You can still use prc_platform_pub_listing_default_args for other query tweaks if needed.

Available Support Keys:

Support Key	Description	Provider Plugin
`prc-schema-seo`	SEO meta fields and schema.org output	prc-schema-seo
`prc-social`	Social sharing metadata	prc-social
`prc-bylines`	Staff bylines and acknowledgements	prc-staff-bylines
`prc-art-direction`	Art direction image slots	prc-art-direction
`prc-sitemap`	Include in XML sitemap	prc-schema-sitemap
`prc-related-posts`	Related posts functionality	prc-related-posts
`prc-datasets`	Datasets taxonomy attachment	prc-datasets
`prc-collections`	Collections taxonomy attachment	prc-collections
`prc-publish-workflows`	Watchers list, workflow notifications, and related REST fields on supported posts	prc-publish-workflows

The built-in post type gets this support from prc-publish-workflows automatically (add_post_type_support( 'post', 'prc-publish-workflows' ) on init). Custom post types must add the key to their supports array (or call add_post_type_support()) so get_post_types_by_support( 'prc-publish-workflows' ) includes them when registering meta and REST fields.

Common Meta Fields Across Post Types

Several meta fields are registered across multiple post types:

Meta Key	Description	Registered By
`bylines`	Array of byline term references	prc-staff-bylines
`acknowledgements`	Array of acknowledgement references	prc-staff-bylines
`displayBylines`	Boolean to show/hide bylines	prc-staff-bylines
`reportMaterials`	Report package materials	prc-report-package
`multiSectionReport`	Multi-section report chapters	prc-report-package
`package_parts__enabled`	Enable TOC parts	prc-report-package
`package_parts`	TOC parts data	prc-report-package
`_datacite_doi`	DataCite DOI	prc-schema-academic-identity
`prc_shortlink`	Short link URL	prc-platform-core
`primary_term_id`	Primary category term	prc-platform-core

Post Type Registration Diagram

flowchart TB
    subgraph Core["prc-platform-core"]
        direction TB
        Taxonomies["Shared Taxonomies
        - category
        - research-teams
        - formats
        - regions-countries
        - languages
        - fund-pools
        - mode-of-analysis
        - _post_visibility"]
    end

    subgraph PostLike["prc-post-like-types"]
        direction TB
        PLRegistry["Registry System"]
        ShortRead["short-read"]
        FactSheet["fact-sheet"]
        Decoded["decoded"]
        PressRelease["press-release"]
        Stub["stub"]
    end

    subgraph PageLike["prc-page-like-types"]
        direction TB
        PGRegistry["Registry System"]
    end

    subgraph StaffBylines["prc-staff-bylines"]
        direction TB
        Staff["staff (post type)"]
        Bylines["bylines (taxonomy)"]
        Expertise["areas-of-expertise"]
        StaffType["staff-type"]
        Staff <-.TDS.-> Bylines
    end

    subgraph Collections["prc-collections"]
        direction TB
        CollPT["collections (post type)"]
        CollTax["collection (taxonomy)"]
        CollPT <-.TDS.-> CollTax
    end

    subgraph Datasets["prc-datasets"]
        direction TB
        DataPT["dataset (post type)"]
        DataTax["datasets (taxonomy)"]
        DataPT <-.TDS.-> DataTax
    end

    subgraph Interactive["prc-interactive-features"]
        Feature["feature (post type)"]
    end

    subgraph ChartBuilder["prc-chart-builder"]
        Chart["chart (post type)"]
    end

    subgraph QuizBuilder["prc-quiz-builder"]
        Quiz["quiz (post type)"]
    end

    subgraph BlockArea["prc-block-area-modules"]
        BlockModule["block_module (post type)"]
        BlockAreaTax["block_area (taxonomy)"]
    end

    subgraph Homepages["prc-homepages"]
        Homepage["homepage (post type)"]
    end

    subgraph Notes["prc-notes"]
        Note["note (post type)"]
    end

    Core --> PostLike
    Core --> PageLike
    Core --> StaffBylines
    Core --> Collections
    Core --> Datasets
    Core --> Interactive
    Core --> ChartBuilder
    Core --> QuizBuilder
    Core --> BlockArea
    Core --> Homepages
    Core --> Notes

    StaffBylines --> PostLike
    Collections --> PostLike
    Datasets --> Interactive
    Datasets --> ChartBuilder
    Datasets --> QuizBuilder

Publication Listing Integration

The Publication Listing system (prc-platform-core) manages which post types appear in archive and search results:

flowchart LR
    subgraph Query["Publication Listing Query"]
        WPQuery["WP_Query"]
        CoreQuery["core/query block"]
        RestQuery["REST API"]
    end

    subgraph Filter["prc_platform_pub_listing_default_args"]
        PostTypes["Included Post Types"]
        TaxQuery["Tax Query (visibility)"]
        PostParent["post_parent = 0"]
    end

    subgraph PostTypes["Default Post Types"]
        Post["post"]
        Feature["feature"]
        Quiz["quiz"]
        Collections["collections"]
        Dataset["dataset (search only)"]
        Staff["staff (search only)"]
    end

    Query --> Filter
    Filter --> PostTypes

Notes

All custom post types support custom-fields for block editor meta
Most content post types support revisions for version history
The notes editor support allows internal notes on posts
Research Teams taxonomy drives permalink structure for most content
The TDS pattern enables rich taxonomy pages with full editor content