UserContainer.jsx

import React, { Component } from 'react'
import { connect } from 'react-redux'

class UserContainer extends Component {
    componentDidMount() {
        if (!this.props.user)
            this.props.getUser()
    }

    render () {
        if (!this.props.user)
            return <div>Loading...</div>
        
        return this.props.children
    }
}

export default connect(
    state => ({
        user: state.user,
    }),
    {
        getUser(),
    }
)(UserContainer)

UserPage.jsx

import React from 'react'
import UserContainer from 'containers/user/UserContainer.jsx'

const UserPage = () => (
    <UserContainer>
        This will only show if the user is loaded...
    </UserContainer>
)

export default UserPage