• Introduction
• Check for Software Updates
• AlphaTcl Update Instructions
  • Technical details
  • Implementations
  • Command line tool
• Pros and Cons of Updating Methods
  • Pros and cons of the first method
  • Pros and cons of the second method
  • Pros and cons of the third method
• License and Disclaimer

Introduction

• checking for new releases of the application. This is explained in the Check for Software Updates section.
• updating only the AlphaTcl library embedded in Alpha. This is explained in the AlphaTcl Update Instructions section.

1. using the Alpha ↣ Global Setup ↣ Update Alpha menu items from the running application as explained in this document. This is appropriate in the case of a released version of Alpha (probably installed in the /Applications folder). See the AlphaTcl Update Instructions section.
2. using the Makefile facility as explained in the Technical Note TN #3: How to update AlphaTcl under development. This is appropriate in the case of a built version of Alpha.
3. using the updateAlphaTcl command line tool. This tool is executed from a Terminal window and is able to update the library in any Alpha binary (released, development, etc.). It is documented in the Update AlphaTcl Help file. Note that this method may also be triggered from Alpha (transparently, as if it were the first one) as explained in the Implementations section.

Check for Software Updates

1. The information about the latest release is contained in a file called release_info.json stored on Alpha's project page at SourceForge. This file is downloaded periodically in a background thread during startup. The last check time is cached in the PREFS folder and Alpha won't check again if this date is less than two days from now.
2. Next time Alpha is launched, it reads the release info and, if it detects that a new release is available, it proposes to download and install it.

AlphaTcl Update Instructions

• AlphaTcl User Update
• AlphaTcl Developer Checkout
• AlphaTcl Developer Update

Technical details

• The AlphaTcl User Update item executes an svn export command. This means retrieving the most recent contents of the repository without any Subversion administrative files. This is appropriate for users who just want a fresh version of the files and do not need to place them under version control.
• The AlphaTcl Developer Checkout item executes an svn checkout command. This means retrieving a complete working copy including the Subversion administrative files. This is required for developers who make modifications in the AlphaTcl library and want the files to be under Subversion control (in order to commit their changes to the repository), and is also the most convenient for anyone doing frequent updates. You only execute AlphaTcl Developer Checkout once: subsequently you use the AlphaTcl Developer Update item instead.
• The AlphaTcl Developer Update item executes an svn update command. This is only possible if previously a checkout command has been issued, so that the files are already under Subversion control (which means that the administrative files are already present). This method is efficient because the svn update command is clever and only retrieves the files that have been modified in the repository since the last time you updated.

Implementations

from 'Alpha'

this implementation performs the update by executing the appropriate commands from within Alpha. A progress window is displayed and gives feedback about the files which are received. The downside of this method is that it does not allow any interaction and thus fails in case the user is asked to enter a password or to confirm a certificate. Normally no interaction should be necessary though.

from 'Terminal'

this implementation performs the update from a Terminal window (which finally amounts to applying the third method from Alpha). It launches the Terminal application and executes the appropriate command therein. All the output is printed in the terminal window. If the user is asked to enter a password, this is done in this window. Upon completion, you have to switch back manually to Alpha (and usually are requested to restart the application). This implementation makes use of the command line tool described in the next section.

Command line tool

Pros and Cons of Updating Methods

Pros and cons of the first method

• when you install a new release of the application, you have to extract a new working copy.
• it is awkward to work inside an application's bundle in a deeply buried subdirectory.
• you have only one part of Alpha's code (the library, not the core and the rest).
• this method is not interactive. Yet it may happen that the updating process asks for some sort of authentication or certificate confirmation. In that case, you have no way to reply and the update will fail. If you were updating from a Terminal window (second and third methods), you would be able to type an answer.

Pros and cons of the second method

    make alphatcl-sync

• all the code (library, core, tests, doc, etc.) is kept in a single location.
• it is easily accessible.
• this working copy remains available when a new version of the application is released.

Pros and cons of the third method

License and Disclaimer

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
• Neither the name of the Alpha Community nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.