JSON Schema Editor

A Phoenix LiveComponent for visually building, editing, and validating JSON Schemas.

Features

• Visual Editing: Recursively build and edit deeply nested objects and arrays.
• JSON Viewer: Dedicated component for displaying JSON with syntax highlighting and indentation guides.
• Tabbed Interface: Switch between a visual editor, live JSON preview, and the Test Lab.
• Advanced Logic: Support for oneOf, anyOf, allOf and conditional keywords (if, then, else, not).
• Test Lab: Validate sample JSON data against your schema in real-time with detailed error reporting.
• Schema Generation: Automatically infer a JSON Schema from a pasted JSON object.
• Undo/Redo: Full history support for all schema modifications.
• Real-time Validation: In-editor logic checking (e.g., min <= max) with immediate visual feedback.
• Draft 07 Support: Includes constraints, enums, constants, null type, and $schema management.
• Copy to Clipboard: One-click export of the generated schema.
• Lightweight: Zero external JS dependencies (uses native Phoenix hooks), only requires phoenix_live_view.

Installation

This library uses a small CSS file for styling and a JavaScript hook for clipboard functionality.

1. Add json_schema_editor to your list of dependencies in mix.exs:

def deps do
  [
    {:json_schema_editor, "~> 0.9.3"}
  ]
end

2. Import the library's CSS in your assets/css/app.css (or equivalent):

@import "../../deps/json_schema_editor/assets/css/json_schema_editor.css";

3. Configure JavaScript Hooks (Clipboard Support):

In your assets/js/app.js, import and register the hook:

import { Hooks as JSEHooks } from "../../deps/json_schema_editor/assets/js/json_schema_editor"

// ... existing hooks
let liveSocket = new LiveSocket("/live", Socket, {
  params: {_csrf_token: csrfToken},
  hooks: { ...JSEHooks, ...other_hooks }
})

Usage

The editor supports JSON Schema Draft 07. It automatically injects the $schema URI if not provided.

1. Initialize the Schema

def mount(_params, _session, socket) do
  schema = %{
    "type" => "object",
    "properties" => %{
      "user" => %{
        "type" => "object",
        "properties" => %{
          "name" => %{"type" => "string", "minLength" => 2}
        }
      }
    }
  }

  {:ok, assign(socket, my_schema: schema)}
end

2. Render the Component

<.live_component
  module={JSONSchemaEditor}
  id="json-editor"
  schema={@my_schema}
  on_save={fn updated_schema -> send(self(), {:schema_saved, updated_schema}) end}
/>

3. Handle Updates

def handle_info({:schema_saved, updated_schema}, socket) do
  # The schema is guaranteed to be logically consistent here
  {:noreply, assign(socket, my_schema: updated_schema)}
end

JSON Viewer

You can also use the standalone viewer component to display any JSON data with syntax highlighting.

<JSONSchemaEditor.Viewer.render json={@my_schema} />

It accepts maps, lists, or even raw JSON strings (which it will attempt to decode and pretty-print).

Development

Running Tests

mix test --cover

Running the Demo

elixir examples/demo.exs

Visit http://localhost:4040 to see the editor in action with a sample schema.