@json-render/vue

Vue 3 renderer that converts JSON specs into Vue component trees with data binding, visibility, and actions.

Installation

npm install @json-render/vue @json-render/core zod

Peer dependencies: vue ^3.5.0 and zod ^4.0.0.

Quick Start

Create a Catalog

import { defineCatalog } from "@json-render/core";
import { schema } from "@json-render/vue/schema";
import { z } from "zod";

export const catalog = defineCatalog(schema, {
  components: {
    Card: {
      props: z.object({ title: z.string(), description: z.string().nullable() }),
      slots: ["default"],
      description: "A card container",
    },
    Layout: {
      props: z.object({}),
      slots: ["default", "header", "footer"],
      description: "Layout with named content regions",
    },
    Button: {
      props: z.object({ label: z.string(), action: z.string() }),
      description: "A clickable button",
    },
  },
  actions: {},
});

Define Registry with h() Render Functions

import { h } from "vue";
import { defineRegistry } from "@json-render/vue";
import { catalog } from "./catalog";

export const { registry } = defineRegistry(catalog, {
  components: {
    Card: ({ props, children }) =>
      h("div", { class: "card" }, [
        h("h3", null, props.title),
        props.description ? h("p", null, props.description) : null,
        children,
      ]),
    Layout: ({ slots }) =>
      h("div", null, [
        h("header", null, slots.header?.()),
        h("main", null, slots.default?.()),
        h("footer", null, slots.footer?.()),
      ]),
    Button: ({ props, emit }) =>
      h("button", { onClick: () => emit("press") }, props.label),
  },
});

Named Slots

Use children for the "default" slot. Use the element's top-level slots object for other slot names declared by the catalog:

{
  "type": "Layout",
  "props": {},
  "children": ["main"],
  "slots": {
    "header": ["heading"],
    "footer": ["actions"]
  }
}

Registry components receive Vue-native slot functions. Render them with slots.header?.(), slots.footer?.(), and so on. slots.default?.() renders the spec's children; the children context field is a convenience alias for that rendered result. In the JSON spec, keep default content in children rather than adding a default entry to slots.

Render Specs

<script setup lang="ts">
import { StateProvider, ActionProvider, Renderer } from "@json-render/vue";
import { registry } from "./registry";

const spec = { root: "card-1", elements: { /* ... */ } };
</script>

<template>
  <StateProvider :initial-state="{ form: { name: '' } }">
    <ActionProvider :handlers="{ submit: handleSubmit }">
      <Renderer :spec="spec" :registry="registry" />
    </ActionProvider>
  </StateProvider>
</template>

Providers

Composables

Note: useStateStore().state returns a ShallowRef<StateModel> — use state.value to access.

External Store (StateStore)

Nested lists can set repeat.statePath to { "$item": "field" } inside an enclosing repeat.

Pass a StateStore to StateProvider to wire json-render to Pinia, VueUse, or any state management:

import { createStateStore, type StateStore } from "@json-render/vue";

const store = createStateStore({ count: 0 });

<StateProvider :store="store">
  <Renderer :spec="spec" :registry="registry" />
</StateProvider>

Dynamic Prop Expressions

Props support $state, $bindState, $cond, $template, $computed. Use { "$bindState": "/path" } on the natural value prop for two-way binding.

Visibility Conditions

{ "$state": "/user/isAdmin" }
{ "$state": "/status", "eq": "active" }
{ "$state": "/maintenance", "not": true }
[ cond1, cond2 ]  // implicit AND

Built-in Actions

setState, pushState, removeState, and validateForm are built into the Vue schema and handled by ActionProvider:

{
  "action": "setState",
  "params": { "statePath": "/activeTab", "value": "settings" }
}

Event System

Components use emit(event) to fire events, or on(event) for metadata (shouldPreventDefault, bound).

Streaming

useUIStream and useChatUI return Vue Refs for streaming specs from an API.

BaseComponentProps

For catalog-agnostic reusable components:

import type { BaseComponentProps } from "@json-render/vue";

const Card = ({ props, children }: BaseComponentProps<{ title?: string }>) =>
  h("div", null, [props.title, children]);

Key Exports