Caching images in react js

See also questions close to this topic

• There are always came out an error about the websocket when init a project by using reactjs or vuejs

  When I create a project by using create-react-app or vue init, and execute the command npm run dev/start, it always happened with an error about Websocket on my console tab. I don't understand what the problem is. And the network tab always pending a request about socket constantly.

  WebSocket connection to 'ws://localhost:3000/sockjs-node/863/gwfp1dnj/websocket' failed: Connection closed before receiving a handshake response
• Can't pass an item from a list to a function with Typescript & React

  I am creating a component that loops through and array to make a list, and I want to be able to click an item and then add that to the state of the component:

  <ul className="results-container">
    {results.map((item, index) => {
      return (
        <li className="_item"
          key={index}
          onClick={this._handleSelect}
        >
        {item.suburb} {item.postcode}
        </li>
       )
     })}
   </ul>
  

  My _handleSelect function is where I want to do the logic (I'm just trying to log it out:

  _handleSelect = (event: MouseEvent): void => {
    console.log(event);
  }
  

  I'm always getting type warnings like this:

  Type '(event: FormEvent<HTMLSelectElement>) => void' is not assignable to type '(event: MouseEvent<HTMLLIElement, MouseEvent>) => void'.
    Types of parameters 'event' and 'event' are incompatible.
      Type 'MouseEvent<HTMLLIElement, MouseEvent>' is not assignable to type 'FormEvent<HTMLSelectElement>'.
         Types of property 'currentTarget' are incompatible.
           Type 'EventTarget & HTMLLIElement' is not assignable to type 'EventTarget & HTMLSelectElement'.
  

  (And about 50 others)

  I've searched for every combination I can on Google and nothing answers my question. The closest I have got is the have the function in the list be _handleSelect(item) and the function the be _handleSelect = (item: any) => which did manage to log the items out, but would shortly crash.

  event: MouseEvent returns the class that is attached to the item in the list, which has not target or value properties.
• Login using ldap from reactjs app failing

  I am trying to login from my Reactjs Application to Spring boot ldap(Authentication).

  Though it's working but sometimes I am getting 401 Authentication error but in catch block which is weird.

  Here is my code :

      fd.append('j_username', encodeURI(username))
      fd.append('j_password', encodeURI(password))
  
      try {
  
          const response = await axios({
              url: configs.Data.loginURL,
              method: 'post',
              headers: {
                  'Content-Type': 'application/x-www-form-urlencoded'
              },
              data: fd,
              withCredentials: true
          });
  
          console.log(response);
          if (response.status === 200) {
  
              return { loggedIn: true, error:'', status: response.status }
          } else {
              return { loggedIn: false, error:response.error, status: response.status }
          }
      } catch (err) {
          return { status: err.response.status, error: err.response.statusText }
      }
  

  Spring Security code

  protected void configure(HttpSecurity httpSecurity) throws Exception { httpSecurity.cors().and().csrf().csrfTokenRepository(CookieCsrfTokenRepository.withHttpOnlyFalse()).and().exceptionHandling().authenticationEntryPoint(authenticationEntryPoint()).and().formLogin().loginPage("/login").successHandler(successHandler()).failureHandler(failureHandler()).usernameParameter("j_username").passwordParameter("j_password").permitAll().and().httpBasic().and() .logout().logoutUrl("/logout").invalidateHttpSession(true).deleteCookies("JSESSIONID").logoutSuccessHandler(logoutSuccessHandler()).permitAll().and() .headers().frameOptions().deny().and() .authorizeRequests() .antMatchers("/").permitAll() .antMatchers("/admin/startProcess").access("hasAuthority('MANAGERS') or hasAuthority('SUPERUSER')").anyRequest().authenticated();}

  I am getting logged in successfully and sometimes I am going in catch block of my reactjs application.
• Is there a way to load image from firestore in flutter?

  I'm a newbie to flutter so, i have been trying to load an image in flutter using cachenetworkimage and firestore but im unable to...and here's my code

  Here's a quickview from firestore.

  https://i.imgur.com/xgNX6fs.png

                child: Container(
                  child: Column(
                    children: <Widget>[
                      new FutureBuilder(
                        future: Firestore.instance
                            .collection('images')
                            .getDocuments(),
                        builder: (BuildContext context, AsyncSnapshot snapshot) {
                          if (snapshot.hasData) {
                            if (snapshot.data != null) {
                              print(snapshot.data['homescreen_bannersrc']);
                              return CachedNetworkImage(
                                imageUrl: (snapshot.data['homescreen_bannersrc']),
                                placeholder: (context, url) => new Center(
                                      child: Center(
                                          child: LinearProgressIndicator()),
                                    ),
                                errorWidget: (context, url, error) =>
                                    new Icon(Icons.error),
                                fit: BoxFit.fitWidth,
                              );
                            }
                          }
                        },
                      ),
                    ],
                  ),
                ),
              ),
  
• When I build a widget from a firebase firestore stream, every time the widget its build is counts as a read for firebase billing?

  When I build a widget from a firebase firestore stream, every time the widget is build it count as a read for firebase billing ?
• FCM android block is getting ignored

  This is my payload but when i send it. i am able to receive notification but click_action is getting ignored and it launches the launcher activity.But when i put "click_action" in notification block it is working. Why android block is getting ignored.

  {
  "to": "my tocken",
  "data": {
      "url": "dfhdfh",
      "action": "fhdfg",
  
  },
  "notification": {
      "title": "dfgsdfg",
      "body": "dfgdg"
  },
  "android": {
      "notification": {
          "click_action": "NOTIFICATION_ACTIVITY"
      }
  }
  

  }
• Is there any possible way to open file from remote location or network drive in suitable local application?

  I am working on a problem, but don't know whether it is possible or not. So what I want to do is, I have large files stored on a network or a remote location. I have a page to list all those files e.g. I have 2 files 1) filename1.psd(480 MB) and have a button next to file name "View File", So when I click on filename1.psd it should open that file in locally installed Photoshop 2) filename2.someext (2.03 GB) and have a button next to file name "View File", So when I click on filename1.psd it should open that file in the locally installed application which supports ".someext" filetype automatic

  I want to skip downloading a file because of file sizes are too large.

  So is there any way to launch the installed application from the system with the file path on a link.
• My website can’t be reached, but nothing wrong on GCP

  Error message: webiz.johocen.com took too long to respond. But there is nothing wrong on GCP VM instance. ping webiz.johocen.com got 0% lost 169ms average response

  My website is a WordPress multisite on GCP via bitnami. This happened before, reset the VM will solve the problem, but will happen again sometimes later.

  Any suggestion where I should look into... Thanks
• Align Navigation bar with Header Text on the left side

  I am creating a code portfolio website focused more on game and app development. It has been a while since I have done HTML and I can't figure out how to align a header with the navigation bar. I am unsure if I need to use two separate or if I can do it using CSS.

  For example, I want it to have this effect:

  Youtube Channel          |-----------------------------------| Represents
  Name                     |-----------------------------------| Nav. Bar
  

  Also the nav. bar should be centred between the two lines of text

  This is the code I am working with:

  In the head under :

  ul {
   margin-left: 150px;
   padding: 0px;
   list-style: none;
  }
  .name {
   color: black;
  }
  

  ul will control the entire un-ordered list and .name controls the the header 3

  In the body:

  <h3 class="name">
  Intentionally left blank. Refer to example text
  </h3>
  <ul>
  UN-ordered list for links to other pages. Intentionally not adding the lines because there are a lot of un-needed lines of code here.
  </ul>
  

  When I run it the output is:

  YouTube Channel
  Name
                    |----------------------------| Represents
                    |----------------------------| Nav. Bar
  

  And my desired output is:

  Youtube Channel          |-----------------------------------| Represents
  Name                     |-----------------------------------| Nav. Bar
  
• How can I store the video blob-Data on server with ajax and php

  I want to save the data from a recorded video on server by php and ajax using the script of Media stream recorder from Mido as basic. Only work for audio data, not for video files. The video files are without picture, only audio. The storage of the video and playing by Midos Javascript works fine. Only my script for saving the file on the server is not quite complete or wrong.

  I use this data for the preparation:

  let blob = new Blob(chunks, {type: media.type })
  , url = URL.createObjectURL(blob)
  , li = document.createElement('li')
  , mt = document.createElement(media.tag)
  , hf = document.createElement('a')
  ;
  

  and want to send this by this script:

    var data     = new FormData();
    data.append('file', blob);
    data.append('sessID', sessID);
    data.append('idx', idx);
  
    $.ajax({
      url :  "./srv/lb/recorder/postWave.inc.php",
      type: 'POST',
      data: data,
      contentType: false,
      processData: false,
      success: function(data) {
        console.log('data: '+data);
      },
      error: function() {
        alert("Fehler.");
      }
    });
  

  That is the whole function in Javascript:

  function makeLink() {
    let blob = new Blob(chunks, {type: media.type })
      , url = URL.createObjectURL(blob)
      , li = document.createElement('li')
      , mt = document.createElement(media.tag)
      , hf = document.createElement('a')
    ;
    console.log('url: '+url+'//');
    mt.controls = true;
    mt.src = url;
    hf.href = url;
    hf.download = `${counter++}${media.ext}`;
  //  hf.innerHTML = `download ${hf.download}`;
    li.appendChild(mt);
  //  li.appendChild(hf);
    ul.appendChild(li);
    $('#btnWeiter').css({'visibility':'visible'});
    $('.btn').remove();
  
  //      var filename = 'test.wav';
        var data     = new FormData();
        data.append('file', blob);
        data.append('sessID', sessID);
        data.append('idx', idx);
  
        $.ajax({
          url :  "./srv/lb/recorder/postWave.inc.php",
          type: 'POST',
          data: data,
          contentType: false,
          processData: false,
          success: function(data) {
            console.log('data: '+data);
          },
          error: function() {
            alert("Fehler.");
          }
        });
  }
  

  and that is my php-code:

  $ext = $_POST['idx'] == 1 ? '.ogg' : '.mp4';
  
  if(isset($_FILES['file']) and !$_FILES['file']['error']) {
    $fname = "audio_" . $_POST['sessID'] . $ext;
  
    move_uploaded_file($_FILES['file']['tmp_name'], "../../data/wav/" . $fname);
  }
  

  It works fine with *.ogg files, but the *.mp4 files are only with audio.

  Maybe I have more to do for video files?
• what kind of data should we store in localStorage/sessionStorage/cookies?

  I was going through some blogs about the data caching mechanism in Angular application. In one blog they mentioned localStorage as well, so I was curious to know about

  (1) What kind of data should we cache/store in localStorage/sessionStorage/cookies? (consider security)

  (2) Should we use services in angular or localStorage to store Authentication token received after login?

  (3) Which one is faster in fetching the data in a web application? (localStorage or Angular services)
• why bootstrap modal popup after reload instead of window load. what may be causes?

  I am setting Bootstrap modal window on every page with hidden scroll on background to grab visitor details for lead generation because we are getting enough traffic.

  I am doing all coding with header.php using window on load popup for each time. Popup should be hide after click on close or submit options. and no more popup window on any page after click on close or submit at once.

  i am using session to hide popup after close or submit click. this is working fine.

  is session is safe ? whats other options ?

  what kind of problem i am getting - popup occures after reload instead of window on load.

  looks like cookies issue, header cache issue. i have no idea

  after researching i have done window reload once . its give some variables in url

  check here : https://www.carlo.in/new-cars-test

  please suggest me some other options or provide me solutions.