nixos/tests/fluent-bit: add regression test for #395128 (#395625)

nixos/tests/all-tests.nix

@@ -505,7 +505,7 @@ in
     imports = [ ./firefox.nix ];
     _module.args.firefoxPackage = pkgs.floorp;
   };
-  fluent-bit = handleTest ./fluent-bit.nix { };
+  fluent-bit = runTest ./fluent-bit.nix;
   fluentd = handleTest ./fluentd.nix { };
   fluidd = handleTest ./fluidd.nix { };
   fontconfig-default-fonts = handleTest ./fontconfig-default-fonts.nix { };

nixos/tests/fluent-bit.nix

@@ -1,40 +1,56 @@
-import ./make-test-python.nix (
+# Regression test for https://github.com/NixOS/nixpkgs/pull/395128
-  { lib, pkgs, ... }:
+{
-  {
+  name = "fluent-bit";
-    name = "fluent-bit";
+  nodes.machine = {
-
+    services.fluent-bit = {
-    nodes.machine =
+      enable = true;
-      { config, pkgs, ... }:
+      settings = {
-      {
+        pipeline = {
-        services.fluent-bit = {
+          inputs = [
-          enable = true;
+            {
-          settings = {
+              name = "systemd";
-            pipeline = {
+              systemd_filter = "_SYSTEMD_UNIT=fluent-bit-regression-395128.service";
-              inputs = [
+            }
-                {
+          ];
-                  name = "systemd";
+          outputs = [
-                  systemd_filter = "_SYSTEMD_UNIT=fluent-bit.service";
+            {
-                }
+              name = "file";
-              ];
+              path = "/var/log/fluent-bit";
-              outputs = [
+              file = "fluent-bit.out";
-                {
+            }
-                  name = "file";
+          ];
-                  path = "/var/log/fluent-bit";
-                  file = "fluent-bit.out";
-                }
-              ];
-            };
-          };
         };
-
-        systemd.services.fluent-bit.serviceConfig.LogsDirectory = "fluent-bit";
       };
+    };
+    systemd.services.fluent-bit.serviceConfig.LogsDirectory = "fluent-bit";
 
-    testScript = ''
+    # Logs get compressed when larger than 1024 bytes
-      start_all()
+    # Lets generate some logs that trigger that
+    # This causes libzstd to be dlopen'd by systemd which breaks fluent-bit 3.2.7+
+    # https://www.freedesktop.org/software/systemd/man/latest/journald.conf.html#Compress=
+    systemd.services.fluent-bit-regression-395128 = {
+      serviceConfig = {
+        Type = "oneshot";
+        RemainAfterExit = true;
+      };
+      script = ''
+        for i in {1..20}; do
+          (head -c 1200 < /dev/zero | tr '\0' 'A') && echo
+          sleep 1
+        done
+      '';
+    };
+  };
 
-      machine.wait_for_unit("fluent-bit.service")
+  testScript = ''
-      machine.wait_for_file("/var/log/fluent-bit/fluent-bit.out")
+    start_all()
-    '';
+
-  }
+    machine.wait_for_unit("fluent-bit.service")
-)
+
+    with subtest("fluent-bit handles zstd-compressed journal logs"):
+      machine.succeed("systemctl start fluent-bit-regression-395128.service")
+      machine.succeed("systemctl show -p NRestarts fluent-bit.service | grep -q 'NRestarts=0'")
+
+    machine.wait_for_file("/var/log/fluent-bit/fluent-bit.out")
+  '';
+}