1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
|
# Grafana dashboards, built into a form file-provisioning can actually use.
#
# Returns an attrset of { name = derivation; }, where each derivation is a single
# dashboard JSON file. modules/server.nix drops these into /etc/grafana-dashboards.
{ lib, runCommand, fetchurl, jq, python3, dsUid }:
let
# Dashboards exported from grafana.com carry an `__inputs` block and reference their
# datasource as "''${DS_PROMETHEUS}". That placeholder is only substituted by Grafana's
# interactive *import* flow -- file provisioning never runs it, so the uid stays
# literal and every panel fails to resolve a datasource. Substitute at build time.
#
# A dashboard-level `datasource`-type template variable (lowercase, e.g.
# "''${ds_prometheus}") is a different mechanism and resolves fine on its own; this
# only touches names declared in __inputs.
fixupProgram = ''
def dsuid($pluginId):
if $pluginId == "prometheus" then $prom
elif $pluginId == "loki" then $loki
else "" end;
def subst($name; $uid):
walk(if type == "string" then gsub("\\$\\{" + $name + "\\}"; $uid) else . end);
reduce (.__inputs // [])[] as $i (.; subst($i.name; dsuid($i.pluginId)))
| del(.__inputs, .__requires)
# Provisioned dashboards must not carry an id, or Grafana rejects them on collision
# with whatever already occupies that id in its database.
| .id = null
'';
# One jq invocation, shared by both sources of dashboards below.
#
# Deliberately a single line with no trailing newline: callers append redirections
# (`< $src > "$out"`), and a multi-line string would put those on a line of their own
# as a separate command -- which truncates $out to zero bytes and sends jq's output to
# the build log, without failing the build.
jqFixup = lib.concatStringsSep " " [
"jq"
"--arg prom ${lib.escapeShellArg dsUid.prometheus}"
"--arg loki ${lib.escapeShellArg dsUid.loki}"
(lib.escapeShellArg fixupProgram)
];
fixup = name: src: runCommand "grafana-dashboard-${name}.json"
{ nativeBuildInputs = [ jq ]; }
''
${jqFixup} < ${src} > "$out"
'';
fromGrafanaCom = { name, id, rev, hash }:
fixup name (fetchurl {
url = "https://grafana.com/api/dashboards/${toString id}/revisions/${toString rev}/download";
inherit hash;
});
# The generators and the panel helpers they import.
generators = ../dashboards;
# Our own dashboards are generated here rather than committed as JSON. The JSON is
# machine-written and the generator beside it is the only source of truth, so keeping
# both in git only creates a way for them to drift -- and a build that runs the
# generator cannot serve a stale dashboard. Note flakes copy only git-tracked files
# into the store, so committing the .json is the *only* way to also read it from disk;
# there is no "gitignore it and read it anyway" option.
fromGenerator = { name, generator }:
runCommand "grafana-dashboard-${name}.json"
{
nativeBuildInputs = [ jq python3 ];
# panels.py sits next to the generators and is imported by both of them.
PYTHONPATH = generators;
# The store path is read-only; without this Python warns about __pycache__.
PYTHONDONTWRITEBYTECODE = 1;
}
''
python3 ${generators}/${generator} | ${jqFixup} > "$out"
'';
in
{
# https://grafana.com/grafana/dashboards/1860
node-exporter-full = fromGrafanaCom {
name = "node-exporter-full";
id = 1860;
rev = 45;
hash = "sha256-GExrdAnzBtp1Ul13cvcZRbEM6iOtFrXXjEaY6g6lGYY=";
};
# https://grafana.com/grafana/dashboards/22604
smartctl-exporter = fromGrafanaCom {
name = "smartctl-exporter";
id = 22604;
rev = 2;
hash = "sha256-ci8WE23fZ+ltEKFoUdNNVXsUIV0jqtas79ia2lYIo88=";
};
# Dashboard 15362 ("ZFS Pool Metrics") used to fill this slot. It is an *InfluxDB*
# dashboard -- its queries are InfluxQL against a `zpool_stats` measurement -- so it
# can never render against Prometheus, however it is provisioned. This is a
# Prometheus-native replacement built on the metrics we actually export: node
# exporter's zfs collector plus the ZFS textfile collector.
zfs-pools = fromGenerator { name = "zfs-pools"; generator = "gen_zfs.py"; };
# CrystalDiskInfo-style per-drive SMART view. The Good/Caution/Bad verdict and the
# per-drive row titles both come from the recording rules in rules/smartctl.yml, so
# this one needs those loaded to be useful.
drive-health = fromGenerator { name = "drive-health"; generator = "gen_smart.py"; };
}
|
