nix-bitcoin/modules/versioning.nix
2020-10-16 23:23:00 +02:00

60 lines
1.8 KiB
Nix

{ config, pkgs, lib, ... }:
with lib;
let
version = config.nix-bitcoin.configVersion;
# Sorted by increasing version numbers
changes = [
# None yet
# {
# version = "0.1";
# condition = config.services.foo.enabled;
# message = ''
# demo message
# '';
# }
];
incompatibleChanges = optionals
(version != null && versionOlder lastChange)
(builtins.filter (change: versionOlder change && (change.condition or true)) changes);
errorMsg = ''
This version of nix-bitcoin contains the following changes
that are incompatible with your config (version ${version}):
${concatMapStringsSep "\n" (change: ''
- ${change.message}(This change was introduced in version ${change.version})
'') incompatibleChanges}
After addressing the above changes, set nix-bitcoin.configVersion = "${lastChange.version}";
in your nix-bitcoin configuration.
'';
versionOlder = change: (builtins.compareVersions change.version version) > 0;
lastChange = builtins.elemAt changes (builtins.length changes - 1);
in
{
options = {
nix-bitcoin.configVersion = mkOption {
type = with types; nullOr str;
default = null;
description = ''
Set this option to the nix-bitcoin release version that your config is
compatible with.
When upgrading to a backwards-incompatible release, nix-bitcoin will throw an
error during evaluation and provide hints for migrating your config to the
new release.
'';
};
};
## No config because there are no backwards incompatible releases yet
# config = {
# # Force evaluation. An actual option value is never assigned
# system.extraDependencies = optional (builtins.length incompatibleChanges > 0) (builtins.throw errorMsg);
# };
}