This issue is an overview on the new PHP APIs remaining to be introduced or extended. Important aspects to keep in mind include internal consistency and consistency with other WP family of functions.

General

• *_has_blocks boolean check.
• Add a has_block( $block_name ) variation. Add has_block() function #3773
• Use has_blocks() to augment HTML classes like post_class. Generate body class for Gutenberg pages & provide helper function #4418, PR Add generic has_blocks function #8631
• Expose block data directly through REST API endpoints. Add block data to REST API (post) response data #4763
• Expand get_posts filter parameter to allow a blocks as a return shape. https://core.trac.wordpress.org/ticket/53602
• get_post_blocks() or get_blocks_from_post() returning an array of blocks with their data. PR Introduce get_blocks function #9208
• Strip Blocks from auto-generated excerpts. Strip Blocks from Auto-Generated Excerpts #7268 ; related get_the_excerpt is taking PHP out of memory in a block rendering #5572, PR Introduce strip_dynamic_blocks() for excerpts  #8984
• Make it easier to filter blocks on the server Apply a filter to each rendered static and dynamic block #11523

Block API

• Server-side awareness of block types. Block API: Server-side awareness of block types #2751
• • Introduce block definitions and implementations. Block API: Introduce block definitions and implementations #6733
• • Expose available blocks via an API. Expose available blocks via an API #4116
• • Proper server-side APIs for block modification. Proper server-side APIs for block modification #6494
• Pass the block name to the render callback. Pass the block name to the render callback #4671
• Pass inner content to render callback (optionally?). Pass content to render callback #5760
• Ability to register / hook a callback without the non-idiomatic register_block_type requirement. Calling render_callback() without register_block_type? #4723 Block API: Server-side awareness of block types #2751

To Consider

• A way to define block templates in page headers. Suggestion: Block templates in page template header #3835
• Support for accessing variations of a post in different languages through the REST API. Support for accessing variations of a post in different languages through the REST API #5958

Bugs

• get_the_excerpt is taking PHP out of memory in a block rendering. get_the_excerpt is taking PHP out of memory in a block rendering #5572, PR Introduce strip_dynamic_blocks() for excerpts  #8984