nixpkgs/nixos/modules/services/databases/couchdb.nix
Silvan Mosberger 5e974362be
nixos/couchdb: Prevent it from chowning /var/log to couchdb:couchdb
The default for logFile is /var/log/couchdb.log, and the tmpfile rules chown
${dirOf cfg.logFile}, which is just /var/log, to couchdb:couchdb.

This was found by Edes' report on IRC, which looked like

    Detected unsafe path transition /var/log → /var/log/journal during canonicalization of /var/log/journal

While this bug has been present since the initial couchdb module in
62438c09f7 by @garbas, this wasn't a
problem, because the initial module only created and chowned /var/log
if it didn't exist yet, which can't occur because this gets created in
the initial phases of NixOS startup.

However with the recent move from manual preStart chown scripts to
systemd.tmpfiles.rules in 062efe018d (#59389),
this chown is suddenly running unconditionally at every system
activation, therefore triggering the above error.
2019-07-24 20:52:53 +02:00

202 lines
5.3 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.services.couchdb;
useVersion2 = strings.versionAtLeast (strings.getVersion cfg.package) "2.0";
configFile = pkgs.writeText "couchdb.ini" (
''
[couchdb]
database_dir = ${cfg.databaseDir}
uri_file = ${cfg.uriFile}
view_index_dir = ${cfg.viewIndexDir}
'' + (if useVersion2 then
''
[chttpd]
'' else
''
[httpd]
'') +
''
port = ${toString cfg.port}
bind_address = ${cfg.bindAddress}
[log]
file = ${cfg.logFile}
'');
executable = if useVersion2 then "${cfg.package}/bin/couchdb"
else ''${cfg.package}/bin/couchdb -a ${configFile} -a ${pkgs.writeText "couchdb-extra.ini" cfg.extraConfig} -a ${cfg.configFile}'';
in {
###### interface
options = {
services.couchdb = {
enable = mkOption {
type = types.bool;
default = false;
description = ''
Whether to run CouchDB Server.
'';
};
package = mkOption {
type = types.package;
default = pkgs.couchdb;
defaultText = "pkgs.couchdb";
example = literalExample "pkgs.couchdb";
description = ''
CouchDB package to use.
'';
};
user = mkOption {
type = types.string;
default = "couchdb";
description = ''
User account under which couchdb runs.
'';
};
group = mkOption {
type = types.string;
default = "couchdb";
description = ''
Group account under which couchdb runs.
'';
};
# couchdb options: http://docs.couchdb.org/en/latest/config/index.html
databaseDir = mkOption {
type = types.path;
default = "/var/lib/couchdb";
description = ''
Specifies location of CouchDB database files (*.couch named). This
location should be writable and readable for the user the CouchDB
service runs as (couchdb by default).
'';
};
uriFile = mkOption {
type = types.path;
default = "/run/couchdb/couchdb.uri";
description = ''
This file contains the full URI that can be used to access this
instance of CouchDB. It is used to help discover the port CouchDB is
running on (if it was set to 0 (e.g. automatically assigned any free
one). This file should be writable and readable for the user that
runs the CouchDB service (couchdb by default).
'';
};
viewIndexDir = mkOption {
type = types.path;
default = "/var/lib/couchdb";
description = ''
Specifies location of CouchDB view index files. This location should
be writable and readable for the user that runs the CouchDB service
(couchdb by default).
'';
};
bindAddress = mkOption {
type = types.string;
default = "127.0.0.1";
description = ''
Defines the IP address by which CouchDB will be accessible.
'';
};
port = mkOption {
type = types.int;
default = 5984;
description = ''
Defined the port number to listen.
'';
};
logFile = mkOption {
type = types.path;
default = "/var/log/couchdb.log";
description = ''
Specifies the location of file for logging output.
'';
};
extraConfig = mkOption {
type = types.lines;
default = "";
description = ''
Extra configuration. Overrides any other cofiguration.
'';
};
configFile = mkOption {
type = types.string;
description = ''
Configuration file for persisting runtime changes. File
needs to be readable and writable from couchdb user/group.
'';
};
};
};
###### implementation
config = mkIf config.services.couchdb.enable {
environment.systemPackages = [ cfg.package ];
services.couchdb.configFile = mkDefault
(if useVersion2 then "/var/lib/couchdb/local.ini" else "/var/lib/couchdb/couchdb.ini");
systemd.tmpfiles.rules = [
"d '${dirOf cfg.uriFile}' - ${cfg.user} ${cfg.group} - -"
"f '${cfg.logFile}' - ${cfg.user} ${cfg.group} - -"
"d '${cfg.databaseDir}' - ${cfg.user} ${cfg.group} - -"
"d '${cfg.viewIndexDir}' - ${cfg.user} ${cfg.group} - -"
];
systemd.services.couchdb = {
description = "CouchDB Server";
wantedBy = [ "multi-user.target" ];
preStart = ''
touch ${cfg.configFile}
'';
environment = mkIf useVersion2 {
# we are actually specifying 4 configuration files:
# 1. the preinstalled default.ini
# 2. the module configuration
# 3. the extraConfig from the module options
# 4. the locally writable config file, which couchdb itself writes to
ERL_FLAGS= ''-couch_ini ${cfg.package}/etc/default.ini ${configFile} ${pkgs.writeText "couchdb-extra.ini" cfg.extraConfig} ${cfg.configFile}'';
};
serviceConfig = {
User = cfg.user;
Group = cfg.group;
ExecStart = executable;
};
};
users.users.couchdb = {
description = "CouchDB Server user";
group = "couchdb";
uid = config.ids.uids.couchdb;
};
users.groups.couchdb.gid = config.ids.gids.couchdb;
};
}