Updates¶

Helia can tell you when a newer version exists, and for some installs can install it for you. Nothing is installed without your say-so unless you choose automatic mode, and you can turn the whole thing off.

The three modes¶

Choose the mode on the About page, under Updates, or from a terminal:

helia update config                   # show the mode and channel
helia update config --mode off        # never check on my own
helia update config --mode automatic
helia update config --mode notify     # the default
helia update config --channel prerelease   # include pre-release versions

The choice is kept in update.conf in the Helia settings folder (%APPDATA%\helia on Windows, ~/.config/helia on Linux), shared by the app and the command line. It holds three lines you can edit by hand:

schema=1
mode=notify
channel=stable

The stable channel carries released versions. Pre-release carries those too, plus pre-release builds. If a settings file was written by a newer Helia than the one you are running, Helia reads what it understands, says so, and does not rewrite the file, so going back to an older Helia never loses newer settings.

Checking now¶

On the About page press Check for updates. If there is one, the page names the version, links to what changed, and offers Download and install (or Download, for installs Helia does not replace itself).

From a terminal:

helia update check            # exit code 0: up to date, 10: update available
helia update check --json     # the same answer as JSON
helia update apply            # shows what will happen and asks first
helia update apply --yes      # no question
helia update status           # mode, channel, install type, last check
helia update rollback         # go back to the version the update replaced

Each of these is a subcommand of helia update; the documentation coverage check, which lists subcommands by their last word, knows them as helia check, helia apply, helia status, helia rollback and helia config. The command line never checks by itself; it contacts the update server only when you run check or apply. Exit codes: 0 success (for check: up to date), 1 failed (the message says what, why and what to do), 3 apply or rollback was not confirmed, 10 check found an update, 12 the update details need a newer Helia to read, so update by hand.

What happens for each kind of install¶

Going back¶

If a new version does not start properly twice in a row, the third start puts the previous version back (AppImage: the .previous file; Windows installer: the programs kept before the update), starts it, and records what happened in the log and as a notice (shown by the restored version when it has this feature). That version is not offered again by the daily check, so there is no loop.

You can also go back yourself with helia update rollback. This only works for an update that Helia installed itself, and only while the old version is still kept.

"Starts properly" means the window has been up for a few seconds. A version that crashes before it can record that cannot roll itself back; for that, copy the .previous file over the AppImage by hand, or reinstall the older installer.

Privacy: what is sent¶

Helia has no telemetry. The update check makes these requests and no others:

1. GET of the signed manifest, a small JSON file, from the update server named on the About page (the build's configured address; by default 12hobbies.studio, with the files themselves from GitHub release downloads);
2. GET of its signature (manifest.json.minisig) from the same place;
3. only when you ask (or in automatic mode): GET of the update file itself.

Every request carries only the standard HTTP framing and this identification, with your Helia's version number in place of 0.7.1:

User-Agent: helia-update/0.7.1

No user name, machine name, address you chose, capture name, licence, or any identifier is sent, and no cookies. (An installer bought from the store has its own settings under Updates, and says there what they send.) Redirects are followed only between the servers named in the build (the manifest server for the manifest, the download servers for files), and every address must be https. The server sees your IP address, as any web server does; Helia does not send it anything else. To stop all of it, choose Never check on my own.

How an update is checked¶

Before anything is used, Helia checks that the manifest is signed by the Helia release key built into the program (an Ed25519 signature in the minisign format, up to two keys so the key can be changed), that it is for Helia and the right channel, that it has not expired, that it is not an older copy of one already seen, and that every address is on the allowed servers. The downloaded file must then match the size and SHA-256 in the signed manifest, and is checked again just before it is used. A tampered manifest, a wrong signature, an old manifest replayed, a truncated or altered download and an address on another server are all refused, and nothing on your computer changes. The design and the manifest format are in Automatic updates: design.

If something goes wrong¶

• "could not reach the update server". You are offline or the server is down. Helia carries on as it was; try again later. A failed daily check says nothing; a failed click on Check for updates shows the message.
• "not signed by a key this app trusts". The update details were altered or are from another source. Nothing was installed. Download Helia again from the Helia website.
• "could not install the update ... Nothing was changed". The folder is not writable or the disk is full. The text names the folder. Fix that and try again; the old version is still in place.
• A version that you do not want. Choose Off and download the version you want from the Helia website.