FormKitSwift

Caution

This project is still in early stages and under heavy development. Anything and everything can change. Most of the code is AI generated and hasn't been fully reviewed yet!

FormKitSwift renders native SwiftUI forms from JSON Schema. It owns schema parsing, validation, form session state, serialization, generic tool-edit APIs, and customization hooks without depending on any host app runtime.

Installation

Add the package to a SwiftPM or Xcode project:

.package(url: "https://github.com/YazdanRa/formkit-swift.git", from: "1.2.0")

Then depend on the product:

.product(name: "FormKitSwift", package: "formkit-swift")

Quick Start

import FormKitSwift
import SwiftUI

struct ContentView: View {
    @State private var session = FormKitRenderer().makeFormSession(
        schemaJSON: """
        {
          "type": "object",
          "required": ["name"],
          "properties": {
            "name": { "type": "string", "title": "Name" },
            "active": { "type": "boolean", "title": "Active" }
          }
        }
        """,
        instanceJSON: #"{"name":"Ada","active":true}"#
    )

    var body: some View {
        FormKitView(session: session)
    }
}

You can also let the view create its own session:

FormKitView(schemaJSON: schemaJSON, instanceJSON: instanceJSON)

Use a controlled FormKitSession when the host app needs validation, current JSON, undo/redo, autosave, tool integration, or custom rendering state.

Customization

FormKitOptions controls editing mode, validation behavior, render-engine conditional behavior, labels, colors, field state, and component overrides. Keep JSON Schemas pure; use conditionalRenderBehaviorOverrides for per-pointer render exceptions when building the session:

let session = FormKitRenderer(
    conditionalRenderBehaviorOverrides: ["#/advancedNotes": .ignore]
).makeFormSession(schemaJSON: schemaJSON, instanceJSON: instanceJSON)

FormKitView(
    session: session,
    options: FormKitOptions(
        mode: .editable,
        style: FormKitStyle(accent: .teal, cornerRadius: 8),
        fieldState: { field in
            changedPointers.contains(field.pointer) ? .changed : .normal
        }
    )
)

If the view owns the session, pass the same override map through FormKitOptions. Override keys may use concrete rendered JSON Pointers such as #/advancedNotes or a * segment for repeated array rows, such as #/entries/*/notes.

For deeper customization, set FormKitOptions.components.field or sectionHeader and render with package-owned context types. Future package-native components can be added behind these same options without leaking host app models.

Generic Tool APIs

FormKitSwift exposes generic form-tool models, not assistant-specific APIs:

let context = session.makeToolContext(focusedPointers: ["/notes"])

let result = session.applyToolEdits(
    [
        FormKitToolEdit(
            pointer: "/summary",
            operation: .set,
            value: .string("Inspection complete.")
        )
    ],
    baseRevision: session.revision,
    lockedPointers: ["/notes"]
)

Host apps map FormKitToolContext, FormKitToolEdit, and FormKitToolEditResult to their own assistant, automation, or collaboration protocols.

Supported Surface

The first public package pass focuses on the current renderer behavior:

• object sections and field ordering
• strings, numbers, integers, booleans, dates, times, date-times, enums, nullable scalar values
• arrays of scalar or object items
• defaults, required fields, validation messages, and serialization
• $ref, allOf, oneOf, if/then/else, dependentSchemas, and dependentRequired where supported by the renderer
• unsupported-state rendering for schemas outside the supported form surface

Demo

The demo app lives in Example/FormKitSwiftDemo.

Development setup, demo build, and test instructions live in CONTRIBUTING.md.