Creation Review

Type
Creation
State
Successful
End Date of the Review Period

Reviews run for a minimum of one week. The outcome of the review is decided on this date. This is the last day to make comments or ask questions about this review.

Project
Eclipse LemMinX
Proposal

Eclipse LemMinX

Thursday, November 21, 2019 - 12:30 by Fred Bricon
Basics
This proposal is in the Project Proposal Phase (as defined in the Eclipse Development Process) and is written to declare its intent and scope. We solicit additional participation and input from the community. Please login and add your feedback in the comments section.
Project
Eclipse LemMinX
Parent Project
Eclipse Technology
Proposal State
Created
Background

Many editors are now compatible with the Language Server Protocol (LSP). Several languages (Java, TypeScript, etc) now have a full-featured LSP implementation, but a powerful XML language server is missing from the ecosystem.

Scope

The  LemMinX project provides an LSP implementation for the XML language (aka XML Language Server). It can be used with any editor that supports the protocol, to offer editing support (completion, hyperlink, validation, hover, codelens, ..) for XML documents (.xml, .xsd, .xslt…), as well as schema-based (XSD and DTD) validation.

 

The XML Language Server is extensible via a plugin system (based on a service provider interface - SPI) to provide completion, validation, etc. 

Description

LemMinX provides an implementation of the LSP for XML, written in Java, and based on the Eclipse LSP4J framework.

It implements most of the language server protocol features to provide XML editing support while also exposing extension points for 3rd party adopters to provide custom features via a plugin system. 

Here are some plugin examples:

  • XML syntax/matched grammar validation, via the Xerces XML validator

  • XML completion based on grammar, via Xerces

  • Proof-of-Concept plugins like Maven, emmet or web.xml extensions. 

LemMinX is reusable as a Language Server for downstream projects, but some components, such as the fault-tolerant parser or the service layer can also be reused directly.

Licenses
Eclipse Public License 2.0
Legal Issues

The project code currently depends on:

  • Eclipse LSP4J, to adhere to the LSP protocol

  • The Apache Xerces 2 parser, for parsing and validating XML documents

  • remark, an HTML-to-Markdown renderer, to provide documentation in the markdown format.

A part of the XML parser has been written as a “transcription” of some code present in the VSCode HTML Language Service (copyright @ Microsoft Corporation, MIT-licensed), from TypeScript to Java.

Such pieces of code are clearly identified in their copyright headers.

Why Here?

LemMinX's XML Language Server is based on the Eclipse LSP4J project. Being part of the Eclipse Community would allow closer collaboration and consumption with/from other related projects and communities, like Eclipse Che, Eclipse LSP4E, Eclipse Wild Web Developer.

Additionally, the project would benefit from being inside the Eclipse.org community by attracting more experienced Eclipse developers who're already contributing to some related projects.

Future Work

Once 

  • Continuous adoption of newer version of the Language Server Protocol and addition of new features from LSP

  • Performance and resource consumption

  • Ease integration in clients

  • Improve features for binding between XML and grammar https://github.com/angelozerr/lsp4xml/issues/373

  • Improve formatting options

  • Fix bugs. See a list of issues for missing features and bugs to fix in LSP4XML. 

Project Scheduling

An initial release based on the initial contribution is planned after the project creation.

People
Project Leads
Fred Bricon
Angelo ZERR
Committers
Angelo Zerr
David Kwon
Fred Bricon
Nikolas Komonen
Interested Parties

Corporate:

  • Red Hat Inc.
  • Pivotal
  • Liferay Inc.

Interested projects: Here are some clients consuming this XML Language Server:

Source Code
Initial Contribution

The initial contribution is a functional implementation, known as LSP4XML, currently hosted on GitHub, with active contributors: https://github.com/angelozerr/lsp4xml. The code provides the necessary code to support known XML features like XML completion, quick fixes, validation (basic and based on XML Schema/DTD)

The copyright mostly belongs to Angelo Zerr and Red Hat, contributions that were made by non-Red Hat contributors were done on files that show the Copyright and license headers, without any concern from contributors. So it's assumed that all contributors have contributed approving the EPL 2 license.

The namespace/package of the project would be org.eclipse.lemminx.

 

Source Repository Type
GitHub
Source Repositories
https://github.com/angelozerr/lsp4xml