Patch mattermost module to allow secrets outside the nix store

This adds a custom mattermost module (`services.mattermost-patched`) which is
identical to the one in nixpkgs except that it also has an option `secretConfig`,
which should point to a file containing all secret parts of the mattermost config
(e.g. mailserver password), and which is merged with the config genereated from
the module at startup time.

This allows us to have a (almost) immutable config without having secrets in the
nix store.

Before deploying this, add a secrets file at /var/lib/mattermost/screts.json
(on the host — there is a bind mount in place so we won't have to enter the
container each time to change something).
This commit is contained in:
stuebinm 2021-03-15 17:04:27 +01:00
parent 3be22b7249
commit a3a4264b38
No known key found for this signature in database
GPG key ID: 695C841098BECF1D
2 changed files with 272 additions and 3 deletions

View file

@ -7,14 +7,28 @@
hostAddress6 = "fd00::42:24";
localAddress6 = "fd00::42:25";
bindMounts."/secrets" = {
hostPath = "/var/lib/mattermost/";
isReadOnly = true;
};
config = {pkgs, config, ...}: {
services.mattermost = {
# have to import these here, since container's dont
# inherit imports of their environment.
imports = [ ../../../modules/mattermost.nix ];
# couldn't figure out how to actually overwrite modules, so now
# there's two mattermost modules ...
services.mattermost-patched = {
enable = true;
siteUrl = "https://mattermost.infra4future.de";
siteName = "Mattermost - Blabla for Future";
listenAddress = "[::]:3000";
mutableConfig = false;
secretConfig = "/secrets/secrets.json";
extraConfig = {
ServiceSettings = {
TrustedProxyIPHeader = [ "X-Forwarded-For" "X-Real-Ip" ];
@ -84,7 +98,6 @@
FeedbackOrganization = "infra4future.de";
EnableSMTPAuth = true;
SMTPUsername = "noreply@infra4future.de";
SMTPPassword = ""; # TODO: how to best read in these?
SMTPServer = "mail.hacc.space";
};
RateLimitSettings.Enable = false;
@ -103,7 +116,6 @@
AnnouncementSettings.EnableBanner = false;
GitLabSettings = {
Enable = true;
Secret = ""; # TODO: how to do secrets?
Id = "mattermost";
Scope = "";
AuthEndpoint = "https://auth.infra4future.de/auth/realms/forfuture/protocol/openid-connect/auth";

257
modules/mattermost.nix Normal file
View file

@ -0,0 +1,257 @@
{ config, pkgs, lib, ... }:
with lib;
let
cfg = config.services.mattermost-patched;
defaultConfig = builtins.fromJSON (builtins.replaceStrings [ "\\u0026" ] [ "&" ]
(readFile "${pkgs.mattermost}/config/config.json")
);
database = "postgres://${cfg.localDatabaseUser}:${cfg.localDatabasePassword}@localhost:5432/${cfg.localDatabaseName}?sslmode=disable&connect_timeout=10";
mattermostConf = foldl recursiveUpdate defaultConfig
[ { ServiceSettings.SiteURL = cfg.siteUrl;
ServiceSettings.ListenAddress = cfg.listenAddress;
TeamSettings.SiteName = cfg.siteName;
SqlSettings.DriverName = "postgres";
SqlSettings.DataSource = database;
}
cfg.extraConfig
];
mattermostConfJSON = pkgs.writeText "mattermost-config-raw.json" (builtins.toJSON mattermostConf);
in
{
options = {
services.mattermost-patched = {
enable = mkEnableOption "Mattermost chat server";
statePath = mkOption {
type = types.str;
default = "/var/lib/mattermost";
description = "Mattermost working directory";
};
siteUrl = mkOption {
type = types.str;
example = "https://chat.example.com";
description = ''
URL this Mattermost instance is reachable under, without trailing slash.
'';
};
siteName = mkOption {
type = types.str;
default = "Mattermost";
description = "Name of this Mattermost site.";
};
listenAddress = mkOption {
type = types.str;
default = ":8065";
example = "[::1]:8065";
description = ''
Address and port this Mattermost instance listens to.
'';
};
mutableConfig = mkOption {
type = types.bool;
default = false;
description = ''
Whether the Mattermost config.json is writeable by Mattermost.
Most of the settings can be edited in the system console of
Mattermost if this option is enabled. A template config using
the options specified in services.mattermost will be generated
but won't be overwritten on changes or rebuilds.
If this option is disabled, changes in the system console won't
be possible (default). If an config.json is present, it will be
overwritten!
'';
};
extraConfig = mkOption {
type = types.attrs;
default = { };
description = ''
Addtional configuration options as Nix attribute set in config.json schema.
'';
};
secretConfig = mkOption {
type = types.nullOr types.str;
default = null;
description = ''
Path to a json file containing secret config values, which should
not be written into the Nix store. If it is not null (the default)
and mutableConfig is set to false, then the mattermost service will
join the file at this path into its config.
Note that this file cannot be used to overwrite values already
specified by the other options of this module.
'';
};
localDatabaseCreate = mkOption {
type = types.bool;
default = true;
description = ''
Create a local PostgreSQL database for Mattermost automatically.
'';
};
localDatabaseName = mkOption {
type = types.str;
default = "mattermost";
description = ''
Local Mattermost database name.
'';
};
localDatabaseUser = mkOption {
type = types.str;
default = "mattermost";
description = ''
Local Mattermost database username.
'';
};
localDatabasePassword = mkOption {
type = types.str;
default = "mmpgsecret";
description = ''
Password for local Mattermost database user.
'';
};
user = mkOption {
type = types.str;
default = "mattermost";
description = ''
User which runs the Mattermost service.
'';
};
group = mkOption {
type = types.str;
default = "mattermost";
description = ''
Group which runs the Mattermost service.
'';
};
matterircd = {
enable = mkEnableOption "Mattermost IRC bridge";
parameters = mkOption {
type = types.listOf types.str;
default = [ ];
example = [ "-mmserver chat.example.com" "-bind [::]:6667" ];
description = ''
Set commandline parameters to pass to matterircd. See
https://github.com/42wim/matterircd#usage for more information.
'';
};
};
};
};
config = mkMerge [
(mkIf cfg.enable {
users.users = optionalAttrs (cfg.user == "mattermost") {
mattermost = {
group = cfg.group;
uid = config.ids.uids.mattermost;
home = cfg.statePath;
};
};
users.groups = optionalAttrs (cfg.group == "mattermost") {
mattermost.gid = config.ids.gids.mattermost;
};
services.postgresql.enable = cfg.localDatabaseCreate;
# The systemd service will fail to execute the preStart hook
# if the WorkingDirectory does not exist
system.activationScripts.mattermost = ''
mkdir -p ${cfg.statePath}
'';
systemd.services.mattermost = {
description = "Mattermost chat service";
wantedBy = [ "multi-user.target" ];
after = [ "network.target" "postgresql.service" ];
preStart = ''
mkdir -p ${cfg.statePath}/{data,config,logs}
ln -sf ${pkgs.mattermost}/{bin,fonts,i18n,templates,client} ${cfg.statePath}
'' + lib.optionalString (!cfg.mutableConfig) ''
rm -f ${cfg.statePath}/config/config.json
'' + (if cfg.secretConfig == null
then ''
cp ${mattermostConfJSON} ${cfg.statePath}/config/config.json
''
else ''
${pkgs.jq}/bin/jq -s ".[1] * .[0]" ${cfg.secretConfig} ${mattermostConfJSON} > ${cfg.statePath}/config/config.json
'')
+ ''
${pkgs.mattermost}/bin/mattermost config migrate ${cfg.statePath}/config/config.json ${database}
'' + lib.optionalString cfg.mutableConfig ''
if ! test -e "${cfg.statePath}/config/.initial-created"; then
rm -f ${cfg.statePath}/config/config.json
cp ${mattermostConfJSON} ${cfg.statePath}/config/config.json
touch ${cfg.statePath}/config/.initial-created
fi
'' + lib.optionalString cfg.localDatabaseCreate ''
if ! test -e "${cfg.statePath}/.db-created"; then
${pkgs.sudo}/bin/sudo -u ${config.services.postgresql.superUser} \
${config.services.postgresql.package}/bin/psql postgres -c \
"CREATE ROLE ${cfg.localDatabaseUser} WITH LOGIN NOCREATEDB NOCREATEROLE ENCRYPTED PASSWORD '${cfg.localDatabasePassword}'"
${pkgs.sudo}/bin/sudo -u ${config.services.postgresql.superUser} \
${config.services.postgresql.package}/bin/createdb \
--owner ${cfg.localDatabaseUser} ${cfg.localDatabaseName}
touch ${cfg.statePath}/.db-created
fi
'' + ''
chown ${cfg.user}:${cfg.group} -R ${cfg.statePath}
chmod u+rw,g+r,o-rwx -R ${cfg.statePath}
'';
serviceConfig = {
PermissionsStartOnly = true;
User = cfg.user;
Group = cfg.group;
ExecStart = "${pkgs.mattermost}/bin/mattermost" +
(lib.optionalString (!cfg.mutableConfig) " -c ${database}");
WorkingDirectory = "${cfg.statePath}";
Restart = "always";
RestartSec = "10";
LimitNOFILE = "49152";
};
unitConfig.JoinsNamespaceOf = mkIf cfg.localDatabaseCreate "postgresql.service";
};
})
(mkIf cfg.matterircd.enable {
systemd.services.matterircd = {
description = "Mattermost IRC bridge service";
wantedBy = [ "multi-user.target" ];
serviceConfig = {
User = "nobody";
Group = "nogroup";
ExecStart = "${pkgs.matterircd}/bin/matterircd ${concatStringsSep " " cfg.matterircd.parameters}";
WorkingDirectory = "/tmp";
PrivateTmp = true;
Restart = "always";
RestartSec = "5";
};
};
})
];
}