Requirements
- React v16 or higher
- Node 8 or higher
- React DevTools (optional)
This library tries to implement something similar to querySelector
and querySelectorAll
, but through the React VirtualDOM. You can query for React composite elements or HTML elements. It provides two functions resq$
and resq$$
for selecting one or multiple components, respectively.
Installation
$ npm install --save resq
$ yarn add resq
Usage
To get the most out of the library, we recommend you use React Dev Tools to verify the component names you want to select. Granted for basic usage you don't need this as long as you know the component name beforehand, but for Styled components and MaterialUI components it will be of great help.
Type definition
interface RESQNode {
name: 'MyComponent',
node: HTMLElement | null,
isFragment: boolean,
state: string | boolean | any[] | {},
props: {},
children: RESQNode[]
}
resq$(selector: string, element?: HTMLElement): RESQNode
resq$$(selector: string, element?: HTMLElement): Array<RESQNode>
Basic Usage
Take this React App:
// imports
const MyComponent = () => (
<div>My Component</div>
)
const App = () => (
<div><MyComponent /></div>
)
ReactDOM.render(<App />, document.getElementById('root'))
Selecting MyComponent
:
import { resq$ } from 'resq'
const root = document.getElementById('root');
resq$('MyComponent', root);
/*
{
name: 'MyComponent',
node: <div />,
isFragment: false,
state: {},
props: {},
children: []
}
*/
Wildcard selection
You can select your components by partial name use a wildcard selectors:
// imports
const MyComponent = () => (
<div>My Component</div>
)
const MyAnotherComponent = () => (
<div>My Another Component</div>
)
const App = () => (
<div>
<MyComponent />
<MyAnotherComponent />
</div>
)
ReactDOM.render(<App />, document.getElementById('root'))
Selecting both components by wildcard:
import { resq$$ } from 'resq'
const root = document.getElementById('root');
resq$$('My*', root);
/*
[
{
name: 'MyComponent',
node: <div />,
isFragment: false,
state: {},
props: {},
children: []
},
{
name: 'MyAnotherComponent',
node: <div />,
isFragment: false,
state: {},
props: {},
children: []
},
]
*/
Selecting MyAnotherComponent
by wildcard:
import { resq$ } from 'resq'
const root = document.getElementById('root');
resq$('My*Component', root);
/*
{
name: 'MyAnotherComponent',
node: <div />,
isFragment: false,
state: {},
props: {},
children: []
}
*/
Async selection
Going by the same example as in basic usage, if you don't want to pass the root element to the function, you can do it this way:
import { resq$, waitToLoadReact } from 'resq'
async function getReactElement(name) {
try {
await waitToLoadReact(2000) // time in MS to wait before erroring
return resq$(name)
} catch (error) {
console.warn('resq error', error)
}
}
getReactElement('MyComponent')
Filtering selection
You can filter your selections byState
or byProps
. These are methods attached to the RESQNode return objects.
Example app:
// imports
const MyComponent = ({ someBooleanProp }) => (
<div>My Component {someBooleanProp ? 'show this' : ''} </div>
)
const App = () => (
<div>
<MyComponent />
<MyComponent someBooleanProp={true} />
</div>
)
ReactDOM.render(<App />, document.getElementById('root'))
To select the first instance of MyComponent
where someBooleanProp
is true:
import { resq$ } from 'resq'
const root = document.getElementById('root')
const myComponent = resq$('MyComponent', root)
const filtered = myComponent.byProps({ someBooleanProp: true })
console.log(filtered)
/*
{
name: 'MyComponent',
node: <div />,
isFragment: false,
state: {},
props: {
someBooleanProp: true,
},
children: []
}
*/
Deep Matching with exact
flag
If you are in need of filtering byProps
or byState
and require the filter to match exactly every property and value in the object (or nested objects), you can pass the exact
flag to the function:
import { resq$ } from 'resq'
const root = document.getElementById('root')
const myComponent = resq$('MyComponent', root)
const filtered = myComponent.byProps({ someBooleanProp: true }, { exact: true })