Electrum ABC Update Checker

(releases.json)

This directory contains the releases.json file that the Electrum ABC update checker uses to determine when a new version of the application is available.

Update Checker Overview

There is an update-checking facility built-in to the Qt desktop app. The facility basically functions as follows:

1. When the user selects “Check for updates…”, Electrum ABC connects to the URL hard-coded as RELEASES_JSON_URL in electrumabc/constants.py (currently: https://raw.github.com/Bitcoin-ABC/bitcoin-abc/master/electrum/contrib/update_checker/releases.json)
2. It downloads releases.json (the file in this directory)
3. It checks the versions seen in releases.json – if they are newer than the version in the running app, and if the signed message is valid and is signed with one of the addresses hard-coded in update_checker.py, it then informs the user that an update is available.

No automatic updating is performed and the user must manually click on the URL hard-coded in the app to go to the release page.

The purpose of this facility is merely as a convenience for users who aren’t on reddit or aren’t constantly refreshing our website to be able to find out when a new version is available.

It hopefully will decrease the number of users running very old versions of Electrum ABC.

What This Means For You, The Maintainer

You need to update releases.json in this directory whenever a new version is released, and push it to master.

This file contains a dictionary of:

    {
        "version string" : { "bitcoin address" : "signed message" }
    }

• “version string” above is a version of the form MAJOR.MINOR.REV[variant], e.g. “3.3.5” or “3.3.5CS” (in the latter, ‘CS’ is the variant)
• And empty/omitted variant means “Electrum ABC Regular”
• The variant must match the variant in electrumabc/version.py.

How To Update releases.json

1. Release Electrum ABC as normal, updating the version in electrumabc/version.py.
2. After release, or in tandem with releasing, edit releases.json
3. Make sure to replace the entry for the old version with a new entry.
4. So for example if you were on version “3.3.4” before and you are now releasing “3.3.5”, look for “3.3.4” in releases.json, and update it to “3.3.5”
5. Sign the text “3.3.5” with one of the bitcoin addresses listed in electrumabc_gui/qt/update_checker.py. Paste this address and the signed message (replacing the old address and signed message) into the dictionary entry for “3.3.5” in releases.json.
6. Push the new commit with the updated releases.json to master. (Since currently the update_checker.py code looks for this file in master on github).

Example

The old entry:

 "3.3.4": {
 	"bitcoincash:qphax4cg8sxuc0qnzk6sx25939ma7y877uz04s2z82": "G8lW9Wh2/sa2I7Sd0jdAlit+lYwrXFwjG7ZDUEDngSwyPAT29YMKP68hqeaW7+mp4gClY1+qPIAQsFqzPtoMbTw="
 }

Gets replaced with:

"3.3.5": {
 	"bitcoincash:qphax4cg8sxuc0qnzk6sx25939ma7y877uz04s2z82": "HPC+QnKXdxW/V6qeVFGjYKeP9YQ6DL16Y1SQznavG/G7FUEpMK1wnkAj5yO/RW440mvXxds1PpS35RaEMtvbgJw="
 }

Notice how the version string is different, the signing address happened to remain the same, and, of course, the signature is different now.

How Do I Sign?

• Make sure you control one of the bitcoin addresses listed in electrumabc_gui/qt/update_checker.py. (If you do not, modify this file before release to include one of your addresses!)
• Open up Electrum ABC and go to that address in the “Addresses” tab and right click on it, selecting “Sign/Verify Message”
• The message to be signed is the version string you will put into the JSON, so for example the simple string 3.3.5 in the example above.
• Hit sign, and paste the signature text into the JSON (and signing address, of course, if it’s changed).

How do I test the signature

Before pushing the commit to the remote repository, it is possible to test locally that a signature is correct. For this, run the application from sources with the --test-release-notification command line option.

./electrum-abc -v --test-release-notification

To trigger the version check manually, go to the Help menu and click Check for updates.