javascript - Nodejs Expressjs app.get interval -


i need call app.get() multiple times keep updating page. have function calls app.get every , know function writetopage() gets called app.get() gets called once. how can keep updating page app.get() or there better/alternate way achieve want. reason need content variable changes , need update page.

function writetopage(content, page) {     console.log('writetopage called');     app.get(`/${page}`, function (req, res) {         res.send(content);         console.log('content sent');     }); }

app.get() registering handlers called express when client makes matching http request. not call repeatedly. can't cause browser page auto-update in manner. besides, call res.send() once on original page request. after it's been called once, page has been sent browser , work done http request.

if want browser page auto-update, have these types of options:

  1. you can have browser page auto-reload every often. can done either javascript or meta refresh tag. reload fresh copy of page server , if value has been updated, new value show.

  2. you can use recurring ajax call in web page "poll" server looking changed value , when value changed, javascript in page can update value in current page show new value.

  3. you can use websocket or socket.io connection page server , server can automatically push new value page whenever value updated. javascript in page receive new value , update value in current page show new value.


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