README

OnlineUpdaterPkg

A FreePascal package for Lazarus IDE that implements several classes for updating your application by using single zip archive from online repository. The package allows you to embed the updater in your application. Thus, no other external executables are required. Your app already contains full functionality of the updater inside and become self-updated. Just manage this process.

Notes:

1. Updates must be in the public domain. OnlineUpdater uses public data without any authorization. The channel security is provided by HTTPS protocol.

2. OnlineUpdater does not have a scheduling algorithm. You need to implement your own algorithm for scheduling update check times.

3. Package was tested only on the Windows 10.

Supported repository servers:

Features

• Built-in functionality in the target application. No external executables.
• Different servers support.
• Single zip archive for update.
• "What's new" data in user defined format.
• Flexible managing of updating sequence.
• Auto-detecting executable version.
• Regular expressions support for filename templates.

Dependencies

The package depends on OpenSSL, which is used for HTTPS secure communication.

How to use

1. In Lazarus IDE click Package > Open package file (.lpk).
2. Select and open OnlineUpdaterPkg.lpk.
3. In package window click Use > Add to Project.
4. In your code in uses section add OnlineUpdater.
5. Use it and enjoy.
6. See usage example in example directory: example project ou_test.lpi.

For proper work with HTTPS you must have OpenSSL libraries installed. Compile OpenSSL libraries and install it to your system. Or put compiled libraries in your app binary directory. If you don't want compile it yourself use precompiled libraries, e.g. for Windows. If you include OpenSSL software in your product don't forget about OpenSSL license.

API

Requirements

The table summarizes the differences between the updater classes for different servers.

Warning! Do not use instance of TOnlineUpdater class! This class is the ancestor class for specific classes for a particular server such as TGitlabUpdater or similar.

Marks: :red_circle: — required; :large_blue_circle: — optional; space — not used at all.

Common settings

These properties are readable and writable. You can configure it to control the operation of the updater.

Current state

These properties are read-only and show the current state of the updater.

Methods

procedure StartChecking

Method starts checking for updates.

You can verify if the check has started by getting the value of the IsChecking property.

procedure StartDownloading(AForce: Boolean = False)

Method starts downloading zip file and unzips it after successfull download. Must be called after successfull finish of the StartChecking method. Otherwise no action is performed.

You can verify if the download has started by getting the value of the IsDownloading property.

procedure StartFullUpdating

Method combines 2 previously described actions: StartChecking method is performed, then StartDownload method is performed.

function StartReplacing: Boolean

Method starts replacing old files to perform the upgrade.

Returns True if the replacing was actually started.

Usually called at application startup, for example in the FormShow handler.

function IsReplacing: Boolean

Method begins updating process.

If the zip file of the new application was succsessfully downloaded and unzipped then this method copies current running executable into a new file with old suffix and runs it. If these steps were completed without errors, the method returns True, and your application should be terminated as soon as possible so that the application with old suffix can perform files replacement.

Working flow and events

License

Package releases under MIT License. Copyright (c) 2023 Riva.