JSON Schema Diagnostics

A JSON Schema (up to draft/2020-12) validation extension for Visual Studio Code. Provides a language server that validates JSON documents, including JSON Schema documents, against the $schema they declare.

The extension is powered by a Language Server written in C# that uses the fantastic JsonSchema.Net library by Greg Dennis.

Features

Analyzes JSON documents as you type, adding diagnostics for any schema violations.
Diagnostics will show up in the Problems tab, and will "red squiggle" underline the relevant parts of the text. Supports multiple failures on the same element.
Local schema substitution - redirect $schema urls to your local filesystem for faster inner-loop development.

Local schema substitution

During development it is handy to use the real URLs that your schemas will be available from, but still be able to validate them. For example, say you have a schema that you plan to publish to https://company.com/schema/foo, but you're still creating it. Without changing your JSON, you should still be able to validate against that schema prior to publishing it.

[!WARNING] Schema substitution only works for $schema, not $ref. I may add this feature if there is enough demand, but that would require hooking deeper into the guts of the schema validation library I'm using. I figured it would be more useful to get draft/2020-12 support available now than spend a bunch of time doing that...

To configure this, there are a few settings you can configure: Screenshot of settings

The default configuration will expect the schema filenames to match the last segment of the URL. E.g., "https://company.com/schema/foo" will match foo and foo.json in the search paths. The first match will be used. More details on the Glob syntax here

If you have a different pattern, adjust the Search Globs and Search Url Pattern to fit your needs. Here are a few examples:

Url	Expected filename	Pattern to use	Glob to use
https://company.com/schema/abc/def	`abc.def.json`	`^https://.+/(.+)/(.+)$`	`$1.$2.json`
https://company.com/schemas?get=abc	`abc.json`	`https://.+\?get=(.+)$`	`$1.json`
urn://local/abc	`abc.json`	`^urn://local/(.+)$`	`$1.json`
urn://local/abc.json	`abc.json`	`^urn://local/(.+)$`	`$1`

JSON Schema Diagnostics

Peter Rosser

JSON Schema Diagnostics

Features

Local schema substitution

Requirements

Known Issues

Release Notes