React PDF Viewer component using PDF.js (setup the iframe url by https://gist.github.com/vinhlh/22c92f1a9f4fdb72fdbabefee34cef4d)

PdfViewer.js

import React, { Component, PropTypes } from 'react'
import { PDF_VIEWER } from '../configs'

const propTypes = {
    ratio : PropTypes.number,
    file  : PropTypes.string.isRequired
}

const defaultProps = {
    ratio: 56.25
}

class PdfViewer extends Component {
    shouldComponentUpdate(newProps) {
        return this.props.file != newProps.file
    }

    render() {
        const { ratio, file } = this.props

        return (
            <div className="pdf-viewer" style={{ paddingBottom: `${ratio}%` }} content="Loading">
                <iframe src={`${PDF_VIEWER}?file=${file}`} />
            </div>
        )
    }
}

PdfViewer.propTypes    = propTypes
PdfViewer.defaultProps = defaultProps

export default PdfViewer

.pdf-viewer {
    position: relative;
    width:height;
    padding-bottom: 56.25%;

    iframe {
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
    }
}