how to tell react-router to wait until something has happened? - reactjs

I want to configure react-router to wait for Firebase to login (or logout) before rendering any route.
I've seen react-router has an onEnter() hook, but it seems this is an immediate callback, and I haven't quite figured out how I would make react-router wait until firebase triggers an firebase.auth().onAuthStateChanged(...) event.
Does react-router include some functionality to handle such cases?

The onEnter hook accepts a third parameter, callback?, which if specified will block loading of the route until it is called.
An example from the react-router repo:
function requireCredentials(nextState, replace, next) {
const query = nextState.location.query
if (query.qsparam) {
serverAuth(query.qsparam)
.then(
() => next(),
() => {
replace('/error')
next()
}
)
} else {
replace('/error')
next()
}
}
and the render method:
render((
<Router history={withExampleBasename(browserHistory, __dirname)}>
<Route path="/" component={App}>
<IndexRoute component={Form} />
<Route path="page" component={Page} onEnter={requireCredentials}/>
<Route path="error" component={ErrorPage}/>
</Route>
</Router>
), document.getElementById('example'))
However, there is a warning about using this for long-running operations in the documentation:
Caution: Using the callback in an enter hook causes the transition to wait until it is called. This can lead to a non-responsive UI if you don't call it very quickly.

I fixed it using a main component in my hierarchy that prevents children to be rendered until something has happened.
Here is the implementation. Not the most elegant code, but it works in case you are desperate as I was.

Related

Why is my custom hook not re-initialised on path change?

I am using ReactRouter to route the application (BrowserRouter at the top level) with a Switch that includes all the routes.
In my use-case I want to be able to handle paths that include the path-parameters (bedId) and navigate between different sub-paths (i.e. /beds/:bedId/, /beds/:bedId/info/) as well asa case where the path is (/beds/-).
I also want to be able to direct user to a different "bed" while they are already on some bed, so /beds/bed1/info -> /beds/bed2, and so on...
My BedView component is responsible for routing within that /beds/:bedId path like so:
// App.jsx (fragment)
<Switch>
<Route
path="/"
exact
render={() => (<Redirect to="/beds/-"/>)}
/>
<Route
path="/beds/-"
exact
component={SomeOtherComponent}
/>
<Route
path="/beds/:bedId"
component={BedView}
/>
</Switch>
The problem occurs when I try to use a hook that relies on the current path-parameter to fetch the latest data (i.e. call to /beds/bed1 will result in a call to http://myapi.com/beds/bed1/timeseries). The useLatestData hook is called from the BedView component, which look like so:
// BedView.jsx (fragment)
export default function BedView(props) {
const {bedId} = props.match.params;
let {path, url} = useRouteMatch('/beds/:bedId');
const bedData = useLatestData({
path: `/beds/${bedId}/timeseries`,
checksumPath: `/checksum/timeseries`,
refresh: false
});```
if(!bedData){
return <Loading/>;
}
return (
<Switch>
<Route exact path={path}>
<Redirect to={`${url}/info`}/>
</Route>
<Route exact path={`${path}/info`} >
<SomeComponent info={bedData.info} />
</Route>
</Switch>
}
...and the useLatestData hook is available here.
The problem is the fact that upon redirecting from /beds/bed1/info to /beds/bed2/info, the hook does not update its props, even though the BedView component seems to be re-rendering. I have created a version of the hook that 'patches' the problem by adding an useEffect hook in my custom hook, to detect the change in path (as supplied in the function arguments) and set data to null, but then the behaviour changes on the BedView.jsx's end - making the following check fail:
if(!bedData){
return <Loading/>;
}
I'm not entirely sure which part is the culprit here and any guidance would be much appreciated! As far as I'm aware, the hook is no re-initialised because the path change still results in the same component. There is also one caveat, once I change the BrowserRouter to include the forceRefresh flag, everything works fine. Naturally, I don't want my page to refresh with every redirect though...
try this:
const {bedId} = props.match.params;
let {path, url} = props.match;

React. How to redirect early in a component lifecycle

This seems so simple, but I am new to react and trying different approaches and nothing is working for me. (BTW I am a regular contributor but working on my clients machine and can't remember my so password.)
The version of react router is 4.0, and state is stored using redux.
The scenario is that we are changing the order of routing in our application and would like to redirect any users that have Urls with the old structure to the new Url structure. I have tried the following (also note that I have "scrubbed" the names of the page, function calls and variables):
There is a trigger component for the section I need to direct from, with routing set up like this:
<Route path='page/:pageGuidGuid' component={PageTrigger}> </Route>
In the trigger component, ComponentWillMount makes a request that returns a 404 if the link is from the previous component, although it does redirect to the correct route. I am checking for and triggering the redirect in getInitialState, but the component keeps going through the lifecycle and ComponentWillMount is called, resulting in a 404 and then redirects to the correct page.
const PageTrigger = connectToStores(React.createClass({
getInitialState() {
this.checkForRedirect();
return {};
},
componentWillMount() {
if (this.props.params.guid) {
this.setCaseByGuid(this.props.params.guid);
}
},
checkFrorRedirect() {
/* logic to determine if it should redirect */
browserHistory.push(redirectUrl);
}
}
I have also tried creating a custom route...
<CaseRedirectRoute path='(cases/:caseGuid)' component={CaseTrigger}>
</CaseRedirectRoute>
And in a separate module (based off a login sample)
const CaseRedirectRoute = ({ component: Component, ...rest }) => (
<Route
{...rest} render={props => (
checkForCaseRedirect(...props) ? (
<Redirect to={{
pathname: getCaseUrlRedirectUrl(...props),
state: { from: props.location }
}} />
) : (
<Component {...props} />
)
)} />
);
I have WithRouter imported from react router. When I try to run this I am getting an error inside the react framework:
Uncaught Type Error: Cannot read property 'createRouteFromReactElement' of undefined
at RouteUtils.js:68
at forEachSingleChild (ReactChildren.js:52)
at traverseAllChildrenImpl (traverseAllChildren.js:98)
at traverseAllChildrenImpl (traverseAllChildren.js:114)
at traverseAllChildren (traverseAllChildren.js:186)
at Object.forEachChildren [as forEach] (ReactChildren.js:70)
at createRoutesFromReactChildren (RouteUtils.js:65)
at Function.createRouteFromReactElement (RouteUtils.js:35)
at RouteUtils.js:69
at forEachSingleChild (ReactChildren.js:52)
I've tried redirecting from app.js and page.js, but the PageTrigger is the first component having state set. I either need to figure out how to stop execution after the redirect, or figure out why my custom route keeps blowing up. Any help would be appreciated.
I'm not sure about your setup, but I would implement this redirect as this:
<Route path='oldurl/:p1/:p2' render={
routeProps => (
<Redirect to={'/newUrlHere/'+routeProps.match.params.p1} />
)
} />
So, if the route matches (you may specify exact match if necessary), when the Redirect "renders" it stops rendering and should start the rendering from the new URL. You may build your URL in the Redirect.to property as you wish

Invariant Violation findComponentRoot(...): Unable to find element on redux action dispatch

I have a component, which receives a certain prop from a route - let's call it day. Then, there is a part of redux state - calendar, which I get using connect() and mapStateToProps. Now, when a date is outside of the calendar, in componentWillReceiveProps I dispatch a redux action, to recalculate calendar again to include a date in it. The action is fully synchronous, no requests are being sent. In that case, I get the invariant violation from react:
findComponentRoot(..., .0.1.0.$20160122): Unable to find element
What in what I'm doing is causing the problem? I'm not doing any tables or nested paragraphs/forms. When I dispatch action with setTimeout(..), everything works as expected, so I guess it's some concurrency issue.
This is how my component code looks like:
componentWillReceiveProps(props) {
if (!dateInArray(props.day, props.calendar)) {
props.actions.calculateCalendar(props.day);
// This works:
// setTimeout(() => props.actions.calculateCalendar(props.day), 0);
}
}
#autobind
dateToDiv(date) {
const date8 = toDate8(date);
return <Link className="daySelect" activeClassName="active" key={date8} to={`/date/${date8}`}>{toNiceDate(date)}</Link>
}
render () {
return <div>{this.props.calendar.map(this.dateToDiv)}</div>
}
And this is more or less how my routes look like
<Route path='/' component={App}>
<IndexRedirect to={`date/${today8()}`}/>
<Route path='date'>
<IndexRedirect to={`${today8()}`}/>
<Route path=":day" component={DayView}/>
</Route>
</Route>

Where and How to request data asynchronously to be passed down as props with React Router (v 1)

After reading many questions regarding this topic I am still unsure as to which is the best way to asynchronously fetch data which later will be passed down as props to the child routes with React Router v1.0.0 and up.
My route config looks something like this:
import { render } from 'react-dom';
// more imports ...
...
render(
<Router>
<Route path="/" component={App} />
<IndexRoute component={Dashboard}/>
<Route path="userpanel" component={UserPanel}/>
</Router>,
document.getElementById('container')
)
In my App component I have code which asynchronously fetches data from the backend and will incorporate it into its state, if fetching was successful. I use componentDidMount for this within App.
The state of App will look like this contrived example:
{
user: {
name: 'Mike Smith',
email: 'mike#smith.com'
}
}
I would want to pass the user part of state as props to my IndexRoute and the userpanel route. However I am not sure how I should do this.
A few questions come to mind:
Should I place the async data request somewhere else within my code?
Should I use the React Router api (like onEnter) instead of React lifecycle methods for the data fetching?
How can I pass the state (user) of App to the Dashboard and UserPanel components as props?
I am unsure how to do this with React.cloneElement as seen in other answers.
Thanks for the help in advance.
What you are asking for is persistent data between routes and that's not the job of the router.
You should create a store (in flux terms), or a model/collection (in MVC terms) - the usual approach with react is something flux-like. I recommend redux.
In the redux docs it has an example of fetching a reddit user:
componentDidMount() {
const { dispatch, selectedReddit } = this.props
dispatch(fetchPostsIfNeeded(selectedReddit))
}
Personally I don't think flux/redux is the easiest approach to implement, but it scales well. The essential concept is even if you decide to use something else:
You are correct, as Facebook suggests, async fetching goes best in componentDidMount.
If you want to integrate with other JavaScript frameworks, set timers using setTimeout or setInterval, or send AJAX requests, perform those operations in this method.
Next you need to set this data in a store/model which can be accessed from other components.
The nice thing about redux (with react-redux) is that for each component you can say "Here are the actions this component is interested in" and then that component can simply call the action like UserActions.fetchUserIfNeeded() and the action will figure out whether it already has the user or if it should be fetched, and afterwards it will re-render and the prop will be available.
Answer to Q4: What are you trying to clone and why? If it's a child see this answer.
You can do one thing when your application start at that time you will call the API and fetch the data and register your Route like
my index.js is entry file then
here I have used React-Router 0.13.3 you can change the syntax as per new Router
fetchData(config.url+'/Tasks.json?TenantId='+config.TenantId).then(function(items)
{
var TaskData=JSON.parse(JSON.stringify(items.json.Tasks));
var Data=[];
Object.keys(TaskData).map(function(task){
if(TaskData[task].PageName !=='' && TaskData[task].PageUrl !=='')
{
Data.push({PageName:TaskData[task].PageName,path:TaskData[task].PageName+'/?:RelationId',PageUrl:TaskData[task].PageUrl});
}
});
Data.push({PageName:'ContainerPage',path:'/ContainerPage/?:RelationId',PageUrl:'./pages/ContainerPage'});
var routes=require('./routes')(Data);
$("#root").empty();
Router.run(routes,function(Handler){
React.render(<Handler />,document.getElementById('root'));
});
React.render(<UserRoles />, document.getElementById("userrole"));
}).catch(function(response)
{
showError(response);
});
I have pass the data to routes.js file like var routes=require('./routes')(Data); and my routes.js file look like
export default (data =>
<Route name="App" path="/" handler={App}>
<NotFoundRoute handler={require('./pages/PageNotFound')} />
<Route handler={TaskList} data={data} >
</Route>
{ data.map(task =>
<Route name={task.PageName} path={task.path} handler={require(task.PageUrl)}>
</Route>
) }
</Route>
);
I am not entirely sure I understand the question, but I just recently passed properties to the children of my routes as well. Pardon me if this is not the best way of doing it, but you'll have to clone your children and edit them and then pass down the copies not the children. I'm not sure why react and the react router make you do this, but try this:
let children (or whatever you want to name it) = React.Children.map(this.props.children, (child) => {
return React.cloneElement(child, {name of property: property value});
});
Afterwards, you should be able to access those properties in this.props in the sub routes. Please ask if you have any questions because this is pretty confusing.

How to use back button with React Router

I am having problem with ReactRouter.
Here how I init and run the router:
var routes = (
<Route handler={App}>
<DefaultRoute handler={Domains}/>
<Route path="login" name="login" handler={Login}/>
<Route path="signup" name="signup" handler={SignUp}/>
</Route>);
var config = {routes, location: Router.HistoryLocation};
const router = Router.create(config);
export default router;
$(document).ready(() => {
router.run( (Root) => {
React.render(<Root/>, document.getElementById('maincontent'));
});
});
Reading the docs, this way I expect that I when press the Back button of the browser, or use the goBack() method the browser go to the previous page.
Instead, when I use goBack() method, first remove an hash from the url (that the method transitionTo added), and only after call it again, it works. The same for the button.
Per the docs, if you want to use HistoryLocation you have to configure your server to handle it..
React Router Documentation - HistoryLocation
(a nodejs example):
app.get('*', function (req, res) {
res.render('index');
});
Otherwise, you'll need to use HashLocation as that will keep it on the same page.
If that is set correctly, you can debug what's going on in the router by receiving the 2nd prop in router.run -- state.
Here's the properties state contains.
Router.run(routes, function(Handler, state) {
console.log(state);
React.render(<Handler>);
});

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