From a61e43e18e3a9af975842c50f0dfb927e2b04927 Mon Sep 17 00:00:00 2001
From: Daniel Sampliner <samplinerD@gmail.com>
Date: Fri, 15 Nov 2024 18:02:26 -0500
Subject: [PATCH] nixos/netdata: copy apps_groups.conf instead of symlink

Currently, it is not possible to configure `apps.plugin` via NixOS
option `services.netdata.configDir."apps_groups.conf"`. This is because
`apps.plugin` explicitly does not follow symbolic links when reading its
configuration from apps_groups.conf[^ref].

This change will copy that file instead of symlinking to address this.

Fixes #255161

[^ref]: https://github.com/netdata/netdata/blob/3849e70f93d9c13097e80823a5e0a0fa2c6ea39c/src/collectors/apps.plugin/apps_plugin.c#L679
---
 nixos/modules/services/monitoring/netdata.nix |  2 +-
 nixos/tests/netdata.nix                       | 14 +++++++++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/nixos/modules/services/monitoring/netdata.nix b/nixos/modules/services/monitoring/netdata.nix
index 6e18ef562b8f9..c848c565d5269 100644
--- a/nixos/modules/services/monitoring/netdata.nix
+++ b/nixos/modules/services/monitoring/netdata.nix
@@ -27,7 +27,7 @@ let
     mkdir $out
     ${concatStringsSep "\n" (mapAttrsToList (path: file: ''
         mkdir -p "$out/$(dirname ${path})"
-        ln -s "${file}" "$out/${path}"
+        ${if path == "apps_groups.conf" then "cp" else "ln -s"} "${file}" "$out/${path}"
       '') cfg.configDir)}
   '';
 
diff --git a/nixos/tests/netdata.nix b/nixos/tests/netdata.nix
index df4d342905c68..0ae1f9c137fee 100644
--- a/nixos/tests/netdata.nix
+++ b/nixos/tests/netdata.nix
@@ -14,6 +14,10 @@ import ./make-test-python.nix ({ pkgs, ...} : {
           services.netdata = {
             enable = true;
             python.recommendedPythonPackages = true;
+
+            configDir."apps_groups.conf" = pkgs.writeText "apps_groups.conf" ''
+              netdata_test: netdata
+            '';
           };
         };
     };
@@ -33,12 +37,20 @@ import ./make-test-python.nix ({ pkgs, ...} : {
     # check if netdata can read disk ops for root owned processes.
     # if > 0, successful. verifies both netdata working and
     # apps.plugin has elevated capabilities.
-    url = "http://localhost:19999/api/v1/data\?chart=user.root_disk_physical_io"
+    url = "http://localhost:19999/api/v1/data?chart=user.root_disk_physical_io"
     filter = '[.data[range(10)][2]] | add | . < 0'
     cmd = f"curl -s {url} | jq -e '{filter}'"
     netdata.wait_until_succeeds(cmd)
 
     # check if the control socket is available
     netdata.succeed("sudo netdatacli ping")
+
+    # check that custom groups in apps_groups.conf are used.
+    # if > 0, successful. verifies that user-specified apps_group.conf
+    # is used.
+    url = "http://localhost:19999/api/v1/data?chart=app.netdata_test_cpu_utilization"
+    filter = '[.data[range(10)][2]] | add | . > 0'
+    cmd = f"curl -s {url} | jq -e '{filter}'"
+    netdata.wait_until_succeeds(cmd, timeout=30)
   '';
 })