Go Liquid Template Parser

goliquid is a pure Go implementation of Shopify Liquid templates, for use in gojekyll.

Status

• Basics
  • Literals
    • String Escapes
  • Variables
  • Operators (partial)
  • Arrays
  • Whitespace Control
• Tags
  • Comment
  • Control Flow
    • if/else/elsif
    • unless
    • case
      • when
      • else
  • Iteration
    • modifiers (limit, reversed, offset)
    • range
    • break, continue
    • loop variables
    • tablerow
    • cycle
  • Raw
  • Variables
    • Assign
    • Capture
• Filters
  • sort_natural, uniq, escape, truncatewords, url_decode, url_encode
  • everything else

Install

go get -u github.com/osteele/goliquid

Contribute

Setup

make setup

Install Ragel. On macOS: brew install ragel.

Workflow

go generate ./...
go test ./...

Test just the scanner:

cd expressions
ragel -Z scanner.rl && go test

Preview the documentation:

godoc -http=:6060&
open http://localhost:6060/pkg/github.com/osteele/liquid/

References

https://shopify.github.io/liquid

https://help.shopify.com/themes/liquid

https://github.com/Shopify/liquid/wiki/Liquid-for-Designers

Attribution

Package	Author	Description
github.com/leekchan/timeutil	Kyoung-chan Lee	formatting dates
gopkg.in/yaml.v2	Canonical	YAML support
Ragel	Adrian Thurston	scanning expressions

Michael Hamrah's Lexing with Ragel and Parsing with Yacc using Go was essential to understanding go yacc.

The original Liquid engine, of course, for the design and documentation of the Liquid template language. Many of the tag and filter test cases are taken directly from the Liquid documentation.

(That said, this is a clean-room implementation to make sure it just implements the documented design.)

Other Implementations

Go:

• https://godoc.org/github.com/karlseguin/liquid is a partial implementation.
• https://godoc.org/github.com/acstech/liquid is a more active fork of Karl Seguin's implementation.
• https://godoc.org/github.com/hownowstephen/go-liquid is a more recent entry.

https://github.com/Shopify/liquid/wiki/Ports-of-Liquid-to-other-environments lists ports to other languages.

License

MIT License