From a163694dc653204681e067da4e66bfd1f1b59080 Mon Sep 17 00:00:00 2001
From: "Alexander A. Klimov" <alexander.klimov@icinga.com>
Date: Mon, 19 Jun 2023 17:38:52 +0200
Subject: [PATCH 1/2] Config parsing: fail on unknown fields and print them

Useful against config validation or runtime failures
caused by wrong field spelling or YAML indentation.
---
 cmd/icingadb-migrate/main.go | 2 +-
 pkg/config/config.go         | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/cmd/icingadb-migrate/main.go b/cmd/icingadb-migrate/main.go
index 9618ec2f8..eefa14242 100644
--- a/cmd/icingadb-migrate/main.go
+++ b/cmd/icingadb-migrate/main.go
@@ -125,7 +125,7 @@ func parseConfig(f *Flags) (_ *Config, exit int) {
 		return nil, 2
 	}
 
-	if err := yaml.NewDecoder(cf).Decode(c); err != nil {
+	if err := yaml.NewDecoder(cf, yaml.DisallowUnknownField()).Decode(c); err != nil {
 		_, _ = fmt.Fprintf(os.Stderr, "can't parse config file: %s\n", err.Error())
 		return nil, 2
 	}
diff --git a/pkg/config/config.go b/pkg/config/config.go
index 1388ba930..db6662c3e 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -54,7 +54,7 @@ func FromYAMLFile(name string) (*Config, error) {
 	defer f.Close()
 
 	c := &Config{}
-	d := yaml.NewDecoder(f)
+	d := yaml.NewDecoder(f, yaml.DisallowUnknownField())
 
 	if err := defaults.Set(c); err != nil {
 		return nil, errors.Wrap(err, "can't set config defaults")

From af868b1762911be5b43a70b2dd31c0dce501a4d9 Mon Sep 17 00:00:00 2001
From: "Alexander A. Klimov" <alexander.klimov@icinga.com>
Date: Tue, 11 Jul 2023 09:57:54 +0200
Subject: [PATCH 2/2] Config parsing: unit test failure due to unknown fields

---
 pkg/config/config_test.go | 69 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 69 insertions(+)
 create mode 100644 pkg/config/config_test.go

diff --git a/pkg/config/config_test.go b/pkg/config/config_test.go
new file mode 100644
index 000000000..94e377355
--- /dev/null
+++ b/pkg/config/config_test.go
@@ -0,0 +1,69 @@
+package config
+
+import (
+	"github.com/creasty/defaults"
+	"github.com/icinga/icingadb/pkg/logging"
+	"github.com/stretchr/testify/require"
+	"os"
+	"testing"
+)
+
+func TestFromYAMLFile(t *testing.T) {
+	const miniConf = `
+database:
+  host: 192.0.2.1
+  database: icingadb
+  user: icingadb
+  password: icingadb
+
+redis:
+  host: 2001:db8::1
+`
+
+	subtests := []struct {
+		name   string
+		input  string
+		output *Config
+	}{
+		{
+			name:  "mini",
+			input: miniConf,
+			output: func() *Config {
+				c := &Config{}
+				_ = defaults.Set(c)
+
+				c.Database.Host = "192.0.2.1"
+				c.Database.Database = "icingadb"
+				c.Database.User = "icingadb"
+				c.Database.Password = "icingadb"
+
+				c.Redis.Host = "2001:db8::1"
+				c.Logging.Output = logging.CONSOLE
+
+				return c
+			}(),
+		},
+		{
+			name:   "mini-with-unknown",
+			input:  miniConf + "\nunknown: 42",
+			output: nil,
+		},
+	}
+
+	for _, st := range subtests {
+		t.Run(st.name, func(t *testing.T) {
+			tempFile, err := os.CreateTemp("", "")
+			require.NoError(t, err)
+			defer func() { _ = os.Remove(tempFile.Name()) }()
+
+			require.NoError(t, os.WriteFile(tempFile.Name(), []byte(st.input), 0o600))
+
+			if actual, err := FromYAMLFile(tempFile.Name()); st.output == nil {
+				require.Error(t, err)
+			} else {
+				require.NoError(t, err)
+				require.Equal(t, st.output, actual)
+			}
+		})
+	}
+}