Configuration forms

Auto-generate node configuration forms from JSON Schema.

FlowDrop automatically generates configuration forms from JSON Schema definitions. This guide covers static schemas, dynamic runtime forms, and layout control.

Overview

FlowDrop provides three ways to define configuration forms for nodes:

Approach	When to use
Static configSchema	Fields are known ahead of time
Dynamic configEdit.dynamicSchema	Fields depend on external data or user selections
External configEdit.externalEditLink	Configuration is managed by a 3rd-party system

All three approaches can be combined — FlowDrop tries the dynamic schema first, then falls back to the static schema if the fetch fails.

Quick Start

Define configSchema on your node metadata. FlowDrop auto-renders the form:

{
  "id": "calculator",
  "name": "Calculator",
  "configSchema": {
    "type": "object",
    "properties": {
      "operation": {
        "type": "string",
        "title": "Operation",
        "description": "Mathematical operation to perform",
        "default": "add",
        "enum": [
          "add",
          "subtract",
          "multiply",
          "divide",
          "power",
          "sqrt",
          "average",
          "min",
          "max",
          "median",
          "mode"
        ]
      },
      "precision": {
        "type": "integer",
        "title": "Precision",
        "description": "Number of decimal places",
        "default": 2
      }
    }
  },
  ...
}

Field Types and Formats

Basic Types

type	Renders as
string	Text input
number	Number input
integer	Integer input
boolean	Toggle switch
array	Repeatable field list
object	Nested fieldset

Format Overrides

Use format to change how a field renders:

Format	Renders as	Notes
multiline	Textarea	Multi-line text input
hidden	Nothing	Stored in config but not shown in UI
range	Slider	Requires minimum and maximum
json	CodeMirror editor	JSON syntax highlighting and validation
code	CodeMirror editor	Alias for json
markdown	Markdown editor	Toolbar and preview
template	CodeMirror editor	{{ variable }} autocomplete
autocomplete	Text input + suggestions	Fetches options from API

Example

{
  "type": "object",
  "properties": {
    "prompt": {
      "type": "string",
      "title": "Prompt",
      "format": "multiline"
    },
    "temperature": {
      "type": "number",
      "title": "Temperature",
      "format": "range",
      "minimum": 0,
      "maximum": 2,
      "default": 0.7
    },
    "metadata": {
      "type": "object",
      "title": "Metadata",
      "format": "json"
    },
    "internalId": {
      "type": "string",
      "format": "hidden"
    }
  }
}

Select Fields

Simple Enum

{
  "model": {
    "type": "string",
    "title": "Model",
    "enum": ["gpt-4o", "gpt-4o-mini", "claude-3"],
    "default": "gpt-4o-mini"
  }
}

Labeled Options with oneOf

{
  "status": {
    "type": "string",
    "title": "Status",
    "oneOf": [
      { "const": "pending", "title": "Pending" },
      { "const": "in_progress", "title": "In Progress" },
      { "const": "completed", "title": "Completed" }
    ]
  }
}

Multi-Select (Checkboxes)

{
  "tags": {
    "type": "string",
    "title": "Tags",
    "enum": ["urgent", "review", "archive"],
    "multiple": true
  }
}

Autocomplete Fields

Fetch suggestions from a remote API as the user types:

{
  "userId": {
    "type": "string",
    "title": "User",
    "format": "autocomplete",
    "autocomplete": {
      "url": "/api/users/search",
      "queryParam": "q",
      "minChars": 2,
      "debounceMs": 300,
      "labelField": "name",
      "valueField": "id",
      "allowFreeText": false,
      "fetchOnFocus": true
    }
  }
}

Template Fields

Template fields provide CodeMirror editing with {{ variable }} syntax highlighting and autocomplete from connected node outputs:

{
  "prompt": {
    "type": "string",
    "title": "Prompt Template",
    "format": "template",
    "variables": {
      "ports": ["data", "context"],
      "showHints": true
    }
  }
}

UISchema Layout

By default, fields render in property order. Use uiSchema to control layout and grouping — inspired by JSON Forms:

{
  "type": "VerticalLayout",
  "elements": [
    { "type": "Control", "scope": "#/properties/name" },
    { "type": "Control", "scope": "#/properties/model" },
    {
      "type": "Group",
      "label": "Advanced Settings",
      "collapsible": true,
      "defaultOpen": false,
      "elements": [
        { "type": "Control", "scope": "#/properties/temperature" },
        { "type": "Control", "scope": "#/properties/maxTokens" }
      ]
    }
  ]
}

Element Types

Type	Description
Control	Renders a single form field. scope is a JSON Pointer to the property.
VerticalLayout	Stacks child elements vertically.
Group	Wraps elements in a collapsible fieldset with a label.

Special Config Properties

Certain property names trigger automatic behaviors:

Property	Type	Behavior
instanceTitle	string	Overrides the node’s displayed title
instanceDescription	string	Overrides the node’s displayed description
instanceBadge	string	Overrides the node’s badge
nodeType	string	Switches visual rendering type
dynamicInputs	DynamicPort[]	Creates user-defined input handles
dynamicOutputs	DynamicPort[]	Creates user-defined output handles
branches	Branch[]	Creates conditional output paths (gateway nodes)

Dynamic Schema (Runtime)

Use configEdit.dynamicSchema to fetch config schemas from your backend at runtime:

const myNode: NodeMetadata = {
  id: 'dynamic-processor',
  name: 'Dynamic Processor',
  configEdit: {
    dynamicSchema: {
      url: '/api/nodes/{nodeTypeId}/schema',
      method: 'GET',
      parameterMapping: {
        nodeTypeId: 'metadata.id'
      },
      cacheSchema: true,
      timeout: 10000
    },
    showRefreshButton: true
  },
  // Fallback static schema
  configSchema: {
    type: 'object',
    properties: {
      apiKey: { type: 'string', title: 'API Key' }
    }
  }
};

The dynamic schema endpoint should return a JSON Schema object. Multiple response shapes are accepted:

• Direct schema: { type: "object", properties: {...} }
• Wrapped: { data: {...} } or { schema: {...} }
• With UISchema: { configSchema: {...}, uiSchema: {...} }

External Edit Links

For configuration managed by a 3rd-party system:

configEdit: {
  externalEditLink: {
    url: 'https://admin.example.com/nodes/{nodeTypeId}/configure',
    label: 'Configure in Admin Portal',
    icon: 'mdi:open-in-new',
    parameterMapping: {
      nodeTypeId: 'metadata.id'
    },
    openInNewTab: true
  }
}

Standalone ConfigForm

You can render the ConfigForm component independently in svelte projects:

<script>
  import { ConfigForm } from '@flowdrop/flowdrop/editor';

  const schema = {
    type: 'object',
    properties: {
      name: { type: 'string', title: 'Name' },
      email: { type: 'string', title: 'Email' }
    },
    required: ['name', 'email']
  };

  let values = $state({});
</script>

<ConfigForm
  {schema}
  {values}
  onChange={(config) => {
    values = config;
  }}
  onSave={(config) => {
    /* persist */
  }}
/>