auto-views-with-ui-schema

AutoViews

AutoViews is a set of utilities and abstractions which provides functionality to automatically build UI on top of JSONSchema.

To build UI automatically AutoViews uses some abstractions:

• AutoView — React component, which gets JSONSchema, data, optional UISchema as prop and ComponentsRepo as components property in context and renders accordingly
• ComponentsRepo — class that keeps all components, grouped by data types (string, object and others, even custom data types) and optionally with theirs predicate's, which are boolean returning functions that defines ability of this component to render this JSONSchema node.
• UISchema — is JSON that describes specific rules to render that specific JSONSchema node:
  • what component and its settings to use,
  • which ComponentsRepo should be chosen to get component,
  • what UIHints to apply

Each component which is depends on state or other variables could decide which UISchema to use for render or return custom render result.

To address specific JSONSchema node UISchema uses JSONPointer as key and ComponentOptions as value to tell which component and it's setting to use, or what UIHints have to be applied.

Autoview Component

AutoView is component that will automatically render data which is validated with given JSONSchema with components registered in ComponentsRepo and pathed through RepositoryProvider.

To choose what specific component to be used and what UIHints have to be considered AutoView uses UISchema object and utilities.

Events

Components in ComponentsRepo may have AutoViewProps props interface which has optional onChange?: AutoEventHandler and onClick?: AutoEventHandler.

AutoEventHandler is object with next type:

type AutoEventHandler = (
    e: React.SyntheticEvent<HTMLElement>,
    autoEvent: AutoEvent
) => void;

where AutoEvent is something very special:

interface AutoEvent {
    schemaPointer: string;
    pointer: string;
    patch?: Operation[];
}

This events may have JSONPatch operations on given data, which should be handled by application that uses AutoView.

This library provides handy event handlers creators for each JSONPatch operation.

ComponentsRepo

ComponentsRepo is class which accepts string name as constructor parameter. Once you did instance, you can assign components to data types:

const repo = new ComponentsRepo('editComponents');
repo.register('number', {name: 'input', component: NumberInput}

You can have as many components assigned to certain data type as you want. If you need more then one, you may want to add predicate function during registering:

const hasMinMax = node => node.hasOwnProperty('minimum') && node.hasOwnProperty('maximum');
repo.register('number', {name: 'slider', component: Slider, predicate: hasMinMax});

repo.getMatched({type: 'number', minimum: 0, maximum: 10})

Will return array of available components in registration order

[
    {name: 'number', component: NumberInput},
    {name: 'slider', predicate: hasMinMax, component: SliderInput}
]

By default AutoView will pick last component in getMatched array. Unless there is other component specified in UISchema.

ComponentsRepo instance should be provided to the AutoView context.

<RepositoryProvider components={repo}>
    <AutoView {...props}/>
</RepositoryProvider>

UISchema

UISchema is an object that contains information about how to render JSONSchema.

There is a corresponding type UISchema. Here we create a new UISchema and assign our editComponents repository to the UISchema.

Example is valid for geo schema

repo.register('string', {name: 'input', component: TextInput}
repo.register('string', {name: 'coordinateInput', component: CoordinateInput}

const uiSchema = createUISchema({
    editComponents: { // key is repository `name`.
        '/properties/longitude', {name: 'coordinateInput'},
        '/properties/latitude', {name: 'coordinateInput'},
    }
});
// ...
<RepositoryProvider components={repo}>
    <AutoView
        {...props}
        uiSchema={uiSchema}
    />
</RepositoryProvider>

So with the appropriate JSONSchema and data properties the AutoView component will render assigned components from the UIHints at the given JSONPointer's

Options

Component may take some options. When choosing specific component to render certain data type in UISchema you may also set it's options.

const overrides = createUISchema({
    viewComponents: {
        '': {name: 'uppercasable', options: {uppercase: true}}
    }
});

const {select} = clientRenderer.render(
    <RepositoryProvider components={repo}>
        <AutoView schema={schema} data="foo" uiSchema={overrides}/>
    </RepositoryProvider>
);

In this case component that is registered in viewComponents components repository by string type with name uppercasable should get options and accordingly to value of option name uppercase make data: string = 'foo' prop — uppercased in render result.

UIHints

UISchema contains not only rules for one or multiple ComponentsRepo but also keeps list of UIHints which are specific rules for data type. Thus, components which are implementing certain type of data may consider that UIHints.

Same as for ComponentsRepo overrides, UIHints uses JSONPointers.

At the following example we have special UIHints for root JSONSchema which says what order should it have.

Each component that assigned to type object in repo may consider order hint and render result accordingly. This repo contains AutoFields component which is consider order and will consider other object related UIHints.

const schema: CoreSchemaMetaSchema = {
    type: 'object',
    properties: {
        first: {type: 'string'},
        second: {type: 'string'},
        third: {type: 'string'}
    }
};

const ObjectFields = props => (
    <fieldset>
        <AutoFields {...props} />
    </fieldset>
);
const repo = new ComponentsRepo('editComponents');
repo.register('string', {name: 'input', component: TextInput}
repo.register('object', {name: 'fields', component: ObjectFields}

const uiSchema = createUISchema({}, {
    '': {order: ['second', 'third', 'first']}
});

// ...
<RepositoryProvider components={repo}>
    <AutoView
        schema={schema}
        uiSchema={uiSchema}
        data={{first: '', second: '', third: ''}}
    />
</RepositoryProvider>

So this example will render data fields with input in order which is defined in UIHints.

Manipulating UISchema values

There are functions to change UISchema type values in an immutable way:

Adding/changing UIHints:

const emptyUISchema = createUISchema();
const uiSchemaWithHints = setUIHints(
    '/path/in/data',
    {order: ['second', 'third', 'first']},
    emptyUISchema
);

Retrieving UIHints:

const hints = getUIHints('/path/in/data', uiSchemaWithHints);

Removing UIHints:

const uiSchemaWithoutHints = unsetUIHints('/path/in/data', uiSchemaWithHints);

Adding/changing component options:

const emptyUISchema = createUISchema();
const uiSchemaWithComponent = setComponent(
    'repositoryName',
    '/path/in/data',
    {name: 'uppercasable', options: {uppercase: true}},
    original
);

Retrieving component options;

const componentOptions = getComponent(
    'repositoryName',
    '/path/in/data',
    uiSchemaWithComponent
);

Removing component:

const uiSchemaWithoutComponent = unsetComponent(
    'repositoryName',
    '/path/in/data',
    uiSchemaWithComponent
);