LazAutoUpdater

Summary

• LazAutoUpdate is a visual drop-in component for the Lazarus/FPC IDE to make updating your application from an online source easier and smarter.
• When making an app for distribution, coding an update process for users can be a bother, yet users appreciate the facility (so long as it's not forced on them!) and support is easier if you know that the user always has the most up-to-date version of your app. LazAutoUpdate is designed to integrate well with your SourceForge or GitHub version control ensuring a trouble-free experience for you and your users.
• LazAutoUpdate downloads via a background thread so the user can continue using your app without interruption
  • This means for example, your app can 'check for updates' at startup without the app becoming unresponsive.
• It is aimed at Lazarus Windows and Linux developers who host their project in SourceForge or GitHub.
• Drop-in the component, set a couple of properties (your SourceForge project name, or some GitHub properties) and call one simple method:
  • LazAutoUpdate.AutoUpdate
• You (the developer) have plenty of control over how the component behaves, yet it is simple to use.
• End-users see the updating process as simple and transparent
• Tested and developed in Windows 10 64/32-bit and Linux 64/32-bit

Download

• LazAutoUpdate suite installer (Windows) or zip (Linux) can be downloaded from the SourceForge project site
• The Lazarus OnlinePackager also contains LazAutoUpdate

Installation

• Download the Windows setup file or the linuxbinaries zip
• Windows: Install, Linux: Unzip in a spare folder
• Use the UpdatePack to make and distribute your update files
• Use the LazAutoUpdate component to add update functionality to your Lazarus app
  • You will need to distribute updatehm<os>(.exe) with your application for LazAutoUpdate to work correctly
  • Don't forget to set VersionInfo numbers in your Lazarus Project options

Example application

• In the download package is the project 'TestApp'
• Compile and run TestApp (remembering to compile+copy the appropriate console updater (updatehm_xxx) to the executable folder)
  • It should update itself 'out-of-the-box'
• Check out the source code of TestApp to get an idea of how to use LazAutoUpdate to its full potential

Internationalisation

• i8n: LazAutoUpdate has a 'locale' folder with all the .po files needed for translation. The base language is English

Use

• Set a version number for your app in Project/Options/Versioninfo
• Drop the component onto the main form of your application
• Set the SFProjectName property to your SourceForge project name (the same text as appears in the URL for your project page)
• or.. Set the GitHub properties:
  • GitHubProjectname: Username or Organisation
  • GitHubRepositoryName: Your project/repository
  • GitHubBranchOrTag: 'master' for the root or the GitHub Branch name or Tag name
• In both cases set the UpdatesFolder to the location of your update files (you can leave it blank)
• Use the UpdatePack to upload your app to the internet (SourceForge, GitHub etc)
• Then let the component take care of the details. Just use (perhaps as a Help menu item 'Check for updates')

LazAutoUpdate1.AutoUpdate;

• You don't want the user to close your application in the middle of an update! Use this code in the Form.CloseQuery handler:

If LazAutoUpdate1.DownloadInProgress Then
  Begin
  CanClose := False;
  ShowMessage('Please wait. Download is still progress.');
  End;

• After an update your app can show 'What's new' automatically. Put this line into your Form's OnShow event:

LazAutoUpdate1.ShowWhatsNewIfAvailable;

• This gives you the 'bare bones' of the update code for your application. As you can see, it's all pretty automatic and simple.

More control

• Decide if you want your app to check for updates on startup. If so, in your form.activate handler:

If LazAutoUpdate1.NewVersionAvailable Then
      MessageDlg(Application.Title, 'A new version of ' + Application.Title +
        ' is available.' + LineEnding +
        'Click ''Check for new version'' in Help menu to update', mtConfirmation,
        [mbOK], 0);

• If you do not use the AutoUpdate method, you have control over the update process in stages via the functions:

If LazAutoUpdate1.NewVersionAvailable then ..... else ...

If LazAutoUpdate1.DownloadNewVersion then ..... else ...

If LazAutoUpdate1.UpdateToNewVersion then ..... else ...

Debugging

• If you set

LazAutoUpdate1.DebugMode:=TRUE;

then you can use the built-in OnDebugEvent method to log activity:

procedure TForm1.LazAutoUpdate1DebugEvent(Sender: TObject; lauMethodName,
      lauMessage: string);
begin
// Use TEventLog
   Logger.Info('('+lauMethodName+') - ' + lauMessage);
end;

There are also events fired: OnDownloaded and OnNewVersionAvailable and the property LastError with info that you might use for debugging.

Support

• LazAutoUpdate is supported via the Lazarus forum here.

License

• LazaAutoUpdate: LGPLv2 (same as Lazarus components)
• Update Pack: GPLv2

Deploying your Application with LazAutoUpdate

• Use UpdatePack to manage the process.
  • UpdatePack is a GUI application that makes the update files accurately and quickly, and even gives you the corresponding LazAutoUpdate code for your app.
  • It uses 'profiles' that enable you to deploy future updates by simply updating the version number and clicking 'Create Update Pack'.
  • Your app users will benefit from having the latest version of your software always available
• When testing, remember your testing app should be a lower version number than your 'update' app stored online :)
• If you want to make up (or add to) the update zip yourself, it should contain the App and the text file 'whatsnew.txt' as a minimum.

Using auOtherSourceFilename and auOtherSourceURL

• When ProjectType is set to auOther, LazAutoUpdate will use these properties for all the Methods. See example application in the SVN archive.

LazAutoUpdate Systray Application

• This can be found in the /trayicon folder of the source.
• When this is run, it sits in the system tray area and silently checks for updates via a schedule (developer and user configurable)
  • If it finds a new version it pops up a notification to the user to update:
    • If the app not running, the update is done silently in the background
    • If the app is running it closes it and then does the update. The app will then restart
• Systray updater has a right-click menu:
  • Configure:
    • The user can edit the schedule - each app has a 'profile'
  • Runs at startup (Windows):
    • The systray loads silently at each Windows boot
• Systray (lautraynotify) picks up entries from apps that use LazAutoupdate automatically, so it never needs to be configured - simply installed once and forgotten.
• The schedule is flexible, from once every day to once every month
  • The UpdatePack takes care of producing the systray configuration file for your app. The default is to check every Monday at 9am.
• The systray app works in both Windows and Linux - all you need to do is deploy it.

Making a generic online installer/updater

• Once a LazAutoUpdate component has been dropped onto a form, it can be used for multiple updates, downloads etc. (see '/testinstaller' in package source)
• For a generic installer/updater you need to set:
  • VersionsINIFilename
  • ZipFilename
  • AppFileWithPath
  • AppVersion
• By setting these properties dynamically (perhaps via a menu) you can enable the user to update multiple applications hosted on a SourceForge/GitHub project site (or any site using auOther settings - see above)
• Here's example code to use LazAutoUpdate to download then run an application.
• The zipped files for the application (including 'whatsnew.txt') and the file 'mywizzyapp.ini' are located in the /updates subdirectory of the SourceForge project 'mywizzy'
• The executable 'updatehm(ostype)(.exe)' is in the same directory as your updater app
  • ostype=[win32|win64|linux32|linux64]
  • Windows ext=(.exe)
• The user would download a small InnoSetup installer with just the online installer/updater, which in turn would download application(s) and supporting files.
  • Of course, the "installer" could be your main application, with sister applications installable via a menu or some such.

procedure TForm1.Button1Click(Sender: TObject);
// Uses SysUtils,LazFileUtils,ulazautoupdate etc..
Var sDirectoryToInstallTo: string;
begin
sDirectoryToInstallTo := ProgramDirectory + 'installed';
Application.Title:='My whizzy app'
LazAutoUpdate1.WorkingMode := lauInstall;
LazAutoUpdate1.ProjectType := auSourceForge;
LazAutoUpdate1.SFProjectname:='mywizzy';
LazAutoUpdate1.VersionsININame:='mywizzyapp.ini';
LazAutoUpdate1.ZipfileName:='mywizzyapp.zip';
LazAutoUpdate1.AppFileWithPath := sDirectoryToInstallTo + DirectorySeparator + 'mywizzyapp.exe';
// Our responsibility to make the folder
if not DirectoryExistsUTF8(sDirectoryToInstallTo) then ForceDirectoriesUTF8(sDirectoryToInstallTo);
LazAutoUpdate1.Appversion:='0.0.0.0';
If LazAutoUpdate1.DownloadNewVersion then
  begin
    If LazAutoUpdate1.UpdateToNewVersion then
    begin
      LazAutoUpdate1.ShortCut.Category := scUtility;
      LazAutoUpdate1.ShortCut.Target := LazAutoUpdate1.AppFileWithPath;
      LazAutoUpdate1.ShortCut.ShortcutName := Application.Title;
      LazAutoUpdate1.MakeShortCut; // makes a desktop shortcut and a Start menu entry in Windows
    end;
  end;
end;

• You can then programatically run the installed app easily enough:

// Uses asyncprocess
procedure TForm1.RunInstalledApp;
var
  AProcess: TAsyncProcess;
begin
  if not FileExistsUTF8(LazAutoUpdate1.AppFileWithPath) then
  begin
    ShowMessageFmt('%s does not exist! Install it first.',
      [LazAutoUpdate1.AppFileWithPath]);
    Exit;
  end;
  AProcess := TAsyncProcess.Create(nil);
  try
    AProcess.Executable := LazAutoUpdate1.AppFileWithPath;
    AProcess.Execute;
  finally
    Aprocess.Free;
  end;
end;

Public Methods List

• Function NewVersionAvailable: Boolean;
• Function DownloadNewVersion: Boolean;
• Function UpdateToNewVersion: Boolean;
• Procedure ShowWhatsNewIfAvailable;
• Procedure AutoUpdate;
• function AppIsActive
• procedure ResetAppVersion;

Non-published Properties list

• GUIOnlineVersion: String
• ReturnCode: Integer
• DownloadInprogress: Boolean
• AppFileWithPath: String
• AppVersion: String
• LastError: String;
• DebugMode: boolean
• LCLVersion: string
• WidgetSet: string
• FPCVersion: string
• LastCompiled: string
• TargetOS: string
• WindowsAdminCheck: boolean

Deploying multiple updates in a single project

• By default, the ZipFilename is the same as your application, but you can set it to a unique value, and deploy it to your Online Files/updates irectory
• Each application to be updated should have a unique name for the versions.ini file. Set the VersionsINIFilename property.

In case the download takes to long

• VersionCountLimit property determines how long LazAutoUpdate will check for a new version before timing out.
• DownloadCountLimit property determines how long LazAutoUpdate will try downloading the new version before timing out.

Versions.ini

The format is as follows:

;LazAutoUpdate versions file
[versions]
GUI=0.0.2

• The file is small so that it is very quick to download

Source Code and latest versions

• Project Page
• SVN HTTP Checkout

Security

Windows 10

• Windows 10 security will not allow a non-admin user to update applications from the internet (unless it's a Windows Store App). This is a sensible policy in my opinion, and LazAutoUpdate adheres to it.
  • If an 'ordinary user' tries to update an app using LazAutoUpdate, all will go smoothly until the final 'Update app' phase. At that point LazAutoUpdate will pop up a dialog informing the user that an administrator account is needed for the actual update.
  • For an 'admin user', LazAutoUpdate will pop up a UAC dialog (the same as any installer) and proceed upon clicking 'yes' to do the update.
  • If you wish to circumvent this (perhaps with a manifest) LazAutoUpdate has the public property 'WindowsAdminCheck' which you can set to FALSE and avoid the dialog.

Linux

• Linux will do the update without even showing the update console, and the user gets a seamless experience.

Workflow

(Technical explanation)

The Lazarus Auto-Updater workflow for updating a running application is as follows:

• App downloads a small 'version.ini' file from sourceforge or github with version info (it can do this at start-up)
• App compares with its own internal version
• If new version available
  • App deletes any contents of local /updates folder
  • App downloads then unzips it from the web into a local /updates folder
• App uses TAsyncProcess to start the console updater.exe, passing it the name of the file to be updated in the command line
• updater.exe copies a downloaded 'whatsnew.txt' into the App folder and enters Sleep for a few seconds
• Meanwhile App has entered loop checking whether a 'whatsnew.txt' file has been copied into it's directory
• App detects 'whatsnew.txt' and Closes. (in other words the TProcess has started successfully)
• Updater copies /updates/UpdatedApp to App directory.
• Updater uses TProcess to start the updated app
• On Form.Show, App displays 'whatsnew.txt' then deletes it

The User sees:

• Dialog: 'There's a new version of xxx available. Would you like to download it?' Yes/No
• If Yes clicked:
  • Download happens in the background (via a background thread) Optional 'download counter' is shown to indicate progress.
  • User is prevented from closing the app whilst the download is in progress (in Form.CloseQuery)
  • Dialog: 'The update is downloaded. Click OK to install it and restart xxx now' OK
  • User clicks OK
  • A console (DOS window in Windows) opens automatically and the Application closes. The console says 'Please wait updating xxx'
  • After a couple of seconds the console disappears, and the new version of the App starts
  • As soon as the main window is shown, a 'What's New' info box is shown with an OK button
  • User clicks OK button, and never sees the info again

Minesadorada

From the Free Pascal wiki, page "LazAutoUpdater", as it stood on 2022-01-07 after a change by FTurtle, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's Licensing page. If you have concerns about this material, message the admin.