react-inspector

What is react-inspector?

The react-inspector npm package provides a set of development tools for inspecting React component hierarchies in the Chrome Developer Tools. It allows developers to view the current state and props of the components, and also provides a tree view to navigate through the component hierarchy. It is similar to the React Developer Tools extension but can be embedded directly into a React application.

What are react-inspector's main functionalities?

Object Inspector

The Object Inspector allows you to render an interactive tree view of a JavaScript object. It is useful for displaying objects in a more readable format within your React application.

{"<ObjectInspector data={{ a: 1, b: 'string', c: true, d: { nested: 'object' } }} />"}

Table Inspector

The Table Inspector provides a tabular view of arrays or objects. It is particularly useful for displaying a collection of objects in a table format, with sorting capabilities.

{"<TableInspector data={[{ id: 1, name: 'John Doe' }, { id: 2, name: 'Jane Doe' }]} />"}

DOM Inspector

The DOM Inspector is used to inspect and display the DOM tree of an HTML element. It can be used to explore the structure of a web page within a React component.

{"<DOMInspector data={document.body} />"}

Other packages similar to react-inspector

mobx-react-devtools

This package provides tools for debugging MobX React applications. It includes features like observing component updates and rendering performance. While it is specific to MobX, it offers similar inspection capabilities for state and component hierarchies as react-inspector.

why-did-you-render

This package helps track unnecessary re-renders in React applications. It notifies you about potentially avoidable re-renders, which can be useful for performance optimization. It complements react-inspector's functionality by focusing on render performance rather than state and prop inspection.

react-json-view

react-json-view is a package for displaying and editing JSON in a readable format. It provides a similar object inspection functionality as react-inspector but with additional features like editing and copying JSON data.

README

react-inspector

Power of Browser DevTools inspectors right inside your React app. Check out the interactive playground.

Install

NPM:

npm install react-inspector

Recommended versions:

• version 3.0.0: If you are using React 16.8.4 or later.
• version 2.3.1: If you are using an ealier version of React.

<Inspector />

A shorthand for the inspectors.

• <Inspector/> is equivalent to <ObjectInspector> or <DOMInspector> if inspecting a DOM Node.
• <Inspector table/> is equivalent to <TableInspector>.

<ObjectInspector />

Like console.log. Consider this as a glorified version of <pre>JSON.stringify(data, null, 2)</pre>.

How it works

Tree state is saved at root. If you click to expand some elements in the hierarchy, the state will be preserved after the element is unmounted.

API

The component accepts the following props:

data: PropTypes.any: the Javascript object you would like to inspect

name: PropTypes.string: specify the optional name of the root node, default to undefined

expandLevel: PropTypes.number: an integer specifying to which level the tree should be initially expanded.

expandPaths: PropTypes.oneOfType([PropTypes.string, PropTypes.array]): an array containing all the paths that should be expanded when the component is initialized, or a string of just one path

• The path string is similar to JSONPath.
  • It is a dot separated string like $.foo.bar. $.foo.bar expands the path $.foo.bar where $ refers to the root node. Note that it only expands that single node (but not all its parents and the root node). Instead, you should use expandPaths={['$', '$.foo', '$.foo.bar']} to expand all the way to the $.foo.bar node.
  • You can refer to array index paths using ['$', '$.1']
  • You can use wildcard to expand all paths on a specific level
    • For example, to expand all first level and second level nodes, use ['$', '$.*'] (equivalent to expandLevel={2})
• the results are merged with expandLevel

showNonenumerable: PropTypes.bool: show non-enumerable properties.

sortObjectKeys: PropTypes.oneOfType([PropTypes.bool, PropTypes.func]): Sort object keys with optional compare function.

When sortObjectKeys={true} is provided, keys of objects are sorted in alphabetical order except for arrays.

nodeRenderer: PropTypes.func: Use a custom nodeRenderer to render the object properties (optional

• Instead of using the default nodeRenderer, you can provide a custom function for rendering object properties. The default nodeRender looks like this:

  import { ObjectRootLabel } from 'react-inspector'
  import { ObjectLabel } from 'react-inspector'
  
  const defaultNodeRenderer = ({ depth, name, data, isNonenumerable, expanded }) =>
    depth === 0
      ? <ObjectRootLabel name={name} data={data} />
      : <ObjectLabel name={name} data={data} isNonenumerable={isNonenumerable} />;
  

<TableInspector />

Like console.table.

API

The component accepts the following props:

data: PropTypes.oneOfType([PropTypes.array, PropTypes.object]): the Javascript object you would like to inspect, either an array or an object

columns: PropTypes.array: An array of the names of the columns you'd like to display in the table

<DOMInspector />

API

The component accepts the following props:

data: PropTypes.object: the DOM Node you would like to inspect

Usage

import {ObjectInspector, TableInspector} from 'react-inspector';

// or use the shorthand
import Inspector from 'react-inspector';

const MyComponent = ({ data }) =>
  <div>
    <ObjectInspector data={data} />
    <TableInspector data={data} />

    <Inspector data={data} />
    <Inspector table data={data} />
  </div>

let data = { /* ... */ };

ReactDOM.render(
  <MyComponent data={data} />,
  document.getElementById('root')
);

Try embedding the inspectors inside a component's render() method to provide a live view for its props/state (Works even better with hot reloading).

More Examples

Check out the storybook for more examples.

npm install && npm run storybook

Open http://localhost:9001/

Theme

By specifying the theme prop you can customize the inspectors. theme prop can be

1. a string referring to a preset theme ("chromeLight" or "chromeDark", default to "chromeLight")
2. or a custom object that provides the necessary variables. Checkout src/styles/themes for possible theming variables.

Example 1: Using a preset theme:

<Inspector theme="chromeDark" data={{a: 'a', b: 'b'}}/>

Example 2: changing the tree node indentation by inheriting the chrome light theme:

import { chromeLight } from 'react-inspector'

<Inspector theme={{...chromeLight, ...({ TREENODE_PADDING_LEFT: 20 })}} data={{a: 'a', b: 'b'}}/>

Roadmap

Type of inspectors:

• Tree style
  • common objects
  • DOM nodes
• Table style
  • Column resizer
• Group style

Contribution

Contribution is welcome. Past contributors

Additional

• If you intend to capture console.logs, you may want to look at console-feed.
• react-object-inspector package will be deprecated. <ObjectInspector/> is now part of the new package react-inspector.
• Why inline style? This document summarizes it well.