⚙️ [config] Add tests for service configurations with embedded structs tagged with mapstructure:",squash" (#715)

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Copyright (C) 2020-2022 Arm Limited or its affiliates and Contributors.
All rights reserved.
SPDX-License-Identifier: Apache-2.0
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### Description

This PR adds tests to ensure that service configurations with embedded
struct fields that are tagged with `mapstructure:",squash"` will be
flattened and mapped correctly.

It tests configuration mapping from both environment variables as well
as from file.

### Test Coverage

<!--
Please put an `x` in the correct box e.g. `[x]` to indicate the testing
coverage of this change.
-->

- [X]  This change is covered by existing or additional automated tests.
- [ ] Manual testing has been performed (and evidence provided) as
automated testing was not feasible.
- [ ] Additional tests are not required for this change (e.g.
documentation update).

Author: Kem-Gov

.secrets.baseline

@@ -66,6 +66,10 @@
     {
       "path": "detect_secrets.filters.allowlist.is_line_allowlisted"
     },
+    {
+      "path": "detect_secrets.filters.common.is_baseline_file",
+      "filename": ".secrets.baseline"
+    },
     {
       "path": "detect_secrets.filters.common.is_ignored_due_to_verification_policies",
       "min_level": 2
@@ -123,28 +127,28 @@
         "filename": "utils/config/service_configuration_test.go",
         "hashed_secret": "ddcec2f503a5d58f432a0beee3fb9544fa581f54",
         "is_verified": false,
-        "line_number": 35
+        "line_number": 37
       },
       {
         "type": "Secret Keyword",
         "filename": "utils/config/service_configuration_test.go",
         "hashed_secret": "7ca1cc114e7e5f955880bb96a5bf391b4dc20ab6",
         "is_verified": false,
-        "line_number": 533
+        "line_number": 535
       },
       {
         "type": "Secret Keyword",
         "filename": "utils/config/service_configuration_test.go",
         "hashed_secret": "11519c144be4850d95b34220a40030cbd5a36b57",
         "is_verified": false,
-        "line_number": 628
+        "line_number": 630
       },
       {
         "type": "Secret Keyword",
         "filename": "utils/config/service_configuration_test.go",
         "hashed_secret": "15fae91d8fa7f2c531c1cf3ddc745e1f4473c02d",
         "is_verified": false,
-        "line_number": 635
+        "line_number": 637
       }
     ],
     "utils/filesystem/filehash_test.go": [
@@ -272,5 +276,5 @@
       }
     ]
   },
-  "generated_at": "2025-08-08T23:03:50Z"
+  "generated_at": "2025-09-26T12:33:39Z"
 }

changes/20250925204435.feature

@@ -0,0 +1 @@
+:gear: `[config]` Add tests for service configurations with embedded structs tagged with `mapstructure:",squash"`

utils/config/fixtures/env-test.env

@@ -0,0 +1,15 @@
+# These env vars will map to a struct the embeds another struct with no mapstructure tag set (it will expect its struct name to be part of the env var)
+WITH_NO_TAG_TESTBASECFG_EMBEDDED1="embedded 1"
+WITH_NO_TAG_TESTBASECFG_EMBEDDED2="embedded 2"
+WITH_NO_TAG_NON_EMBEDDED1="non-embedded 1"
+WITH_NO_TAG_NON_EMBEDDED2="non-embedded 2"
+# These env vars will map to a struct the embeds another struct with a mapstructure tag set
+WITH_TAG_EMBEDDED_STRUCT_EMBEDDED1="embedded 1"
+WITH_TAG_EMBEDDED_STRUCT_EMBEDDED2="embedded 2"
+WITH_TAG_NON_EMBEDDED1="non-embedded 1"
+WITH_TAG_NON_EMBEDDED2="non-embedded 2"
+# These env vars will map to a struct the embeds another struct with the ",squash" mapstructure tag set
+WITH_SQUASH_TAG_EMBEDDED1="embedded 1"
+WITH_SQUASH_TAG_EMBEDDED2="embedded 2"
+WITH_SQUASH_TAG_NON_EMBEDDED1="non-embedded 1"
+WITH_SQUASH_TAG_NON_EMBEDDED2="non-embedded 2"

utils/config/fixtures/flat-config-test.json

@@ -0,0 +1,5 @@
+{
+  "embedded1": "embedded 1",
+  "embedded2": "embedded 2",
+  "non_embedded1": "non-embedded 1"
+}

utils/config/fixtures/nested-config-test.json

@@ -0,0 +1,11 @@
+{
+  "testbasecfg": {
+    "embedded1": "embedded 1",
+    "embedded2": "embedded 2"
+  },
+  "embedded_struct": {
+    "embedded1": "embedded 1",
+    "embedded2": "embedded 2"
+  },
+  "non_embedded1": "non-embedded 1"
+}

utils/config/service_configuration_test.go

@@ -8,6 +8,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"io/fs"
 	"math/rand"
 	"os"
 	"path/filepath"
@@ -16,6 +17,7 @@ import (
 
 	"github.com/go-faker/faker/v4"
 	validation "github.com/go-ozzo/ozzo-validation/v4"
+	"github.com/joho/godotenv"
 	"github.com/spf13/pflag"
 	"github.com/spf13/viper"
 	"github.com/stretchr/testify/assert"
@@ -776,3 +778,225 @@ func TestServiceConfigurationLoadFromEnvironment(t *testing.T) {
 	assert.True(t, configTest.TestConfig.Flag)
 	assert.False(t, configTest.TestConfig2.Flag)
 }
+
+type TestBaseCfg struct {
+	Embedded1 string `mapstructure:"embedded1"`
+	Embedded2 string `mapstructure:"embedded2"`
+}
+
+func (cfg *TestBaseCfg) Validate() error {
+	return validation.ValidateStruct(cfg,
+		validation.Field(&cfg.Embedded1, validation.Required),
+		validation.Field(&cfg.Embedded2, validation.Required),
+	)
+}
+
+type TestCfgWithEmbeddedCfg struct {
+	TestBaseCfg
+	NonEmbedded1 string `mapstructure:"non_embedded1"`
+	NonEmbedded2 string `mapstructure:"non_embedded2"`
+}
+
+func (cfg *TestCfgWithEmbeddedCfg) Validate() error {
+	// Validate Embedded Structs
+	err := ValidateEmbedded(cfg)
+	if err != nil {
+		return err
+	}
+
+	return validation.ValidateStruct(cfg,
+		validation.Field(&cfg.NonEmbedded1, validation.Required),
+	)
+}
+
+type TestCfgWithEmbeddedCfgWithTag struct {
+	TestBaseCfg  `mapstructure:"embedded_struct"`
+	NonEmbedded1 string `mapstructure:"non_embedded1"`
+}
+
+func (cfg *TestCfgWithEmbeddedCfgWithTag) Validate() error {
+	// Validate Embedded Structs
+	err := ValidateEmbedded(cfg)
+	if err != nil {
+		return err
+	}
+
+	return validation.ValidateStruct(cfg,
+		validation.Field(&cfg.NonEmbedded1, validation.Required),
+	)
+}
+
+type TestCfgWithEmbeddedCfgWithSquashTag struct {
+	TestBaseCfg  `mapstructure:",squash"`
+	NonEmbedded1 string `mapstructure:"non_embedded1"`
+}
+
+func (cfg *TestCfgWithEmbeddedCfgWithSquashTag) Validate() error {
+	// Validate Embedded Structs
+	err := ValidateEmbedded(cfg)
+	if err != nil {
+		return err
+	}
+
+	return validation.ValidateStruct(cfg,
+		validation.Field(&cfg.NonEmbedded1, validation.Required),
+	)
+}
+
+// Config values loaded from file should be correctly mapped onto a struct that embeds another struct with no mapstructure tag set
+func TestEmbeddedServiceConfigurationWithNoTagLoadFromFile(t *testing.T) {
+	os.Clearenv()
+	session := viper.New()
+	testEmbedded := TestCfgWithEmbeddedCfg{}
+	err := LoadFromEnvironment(session, "", &testEmbedded,
+		&TestCfgWithEmbeddedCfg{}, filepath.Join(".", "fixtures", "nested-config-test.json"))
+	require.NoError(t, err)
+	assert.NotEmpty(t, testEmbedded.NonEmbedded1)
+	assert.Equal(t, "non-embedded 1", testEmbedded.NonEmbedded1)
+	assert.Empty(t, testEmbedded.NonEmbedded2)
+	assert.NotEmpty(t, testEmbedded.Embedded1)
+	assert.Equal(t, "embedded 1", testEmbedded.Embedded1)
+	assert.NotEmpty(t, testEmbedded.Embedded2)
+	assert.Equal(t, "embedded 2", testEmbedded.Embedded2)
+}
+
+// Nested config values loaded from file should be correctly mapped onto a struct that embeds another struct with a mapstructure tag set
+func TestEmbeddedServiceConfigurationWithTagLoadFromFile(t *testing.T) {
+	os.Clearenv()
+	session := viper.New()
+	testEmbeddedWithTag := TestCfgWithEmbeddedCfgWithTag{}
+	err := LoadFromEnvironment(session, "", &testEmbeddedWithTag,
+		&TestCfgWithEmbeddedCfgWithTag{}, filepath.Join(".", "fixtures", "nested-config-test.json"))
+	require.NoError(t, err)
+	assert.NotEmpty(t, testEmbeddedWithTag.NonEmbedded1)
+	assert.Equal(t, "non-embedded 1", testEmbeddedWithTag.NonEmbedded1)
+	assert.NotEmpty(t, testEmbeddedWithTag.Embedded1)
+	assert.Equal(t, "embedded 1", testEmbeddedWithTag.Embedded1)
+	assert.NotEmpty(t, testEmbeddedWithTag.Embedded2)
+	assert.Equal(t, "embedded 2", testEmbeddedWithTag.Embedded2)
+}
+
+// Flat config values loaded from file should be correctly mapped onto a struct that embeds another struct with the ",squash" mapstructure tag set
+func TestEmbeddedServiceConfigurationWithSquashTagLoadFromFile(t *testing.T) {
+	os.Clearenv()
+	session := viper.New()
+	testEmbeddedWithSquashTag := TestCfgWithEmbeddedCfgWithSquashTag{}
+	err := LoadFromEnvironment(session, "", &testEmbeddedWithSquashTag,
+		&TestCfgWithEmbeddedCfgWithSquashTag{}, filepath.Join(".", "fixtures", "flat-config-test.json"))
+	require.NoError(t, err)
+	assert.NotEmpty(t, testEmbeddedWithSquashTag.NonEmbedded1)
+	assert.Equal(t, "non-embedded 1", testEmbeddedWithSquashTag.NonEmbedded1)
+	assert.NotEmpty(t, testEmbeddedWithSquashTag.Embedded1)
+	assert.Equal(t, "embedded 1", testEmbeddedWithSquashTag.Embedded1)
+	assert.NotEmpty(t, testEmbeddedWithSquashTag.Embedded2)
+	assert.Equal(t, "embedded 2", testEmbeddedWithSquashTag.Embedded2)
+}
+
+// Nested config values loaded from file should not be correctly mapped onto a struct that embeds another struct with the ",squash" mapstructure tag set
+func TestEmbeddedServiceConfigurationWithSquashTagLoadFromNestedFile(t *testing.T) {
+	os.Clearenv()
+	session := viper.New()
+	testEmbeddedWithSquashTag := TestCfgWithEmbeddedCfgWithSquashTag{}
+	err := LoadFromEnvironment(session, "", &testEmbeddedWithSquashTag,
+		&TestCfgWithEmbeddedCfgWithSquashTag{}, filepath.Join(".", "fixtures", "nested-config-test.json"))
+	require.Error(t, err)
+	assert.NotEmpty(t, testEmbeddedWithSquashTag.NonEmbedded1)
+	assert.Equal(t, "non-embedded 1", testEmbeddedWithSquashTag.NonEmbedded1)
+	assert.Empty(t, testEmbeddedWithSquashTag.Embedded1)
+	assert.NotEqual(t, "embedded 1", testEmbeddedWithSquashTag.Embedded1)
+	assert.NotEqual(t, "embedded 2", testEmbeddedWithSquashTag.Embedded2)
+}
+
+// Nested config values loaded from file should be correctly mapped onto a struct that embeds another struct and should maintain any defaults not overwritten
+func TestEmbeddedServiceConfigurationLoadFromFileWithDefaults(t *testing.T) {
+	os.Clearenv()
+	session := viper.New()
+	testEmbedded := TestCfgWithEmbeddedCfg{}
+	defaults := &TestCfgWithEmbeddedCfg{
+		TestBaseCfg: TestBaseCfg{
+			Embedded1: "a",
+			Embedded2: "b",
+		},
+		NonEmbedded1: "c",
+		NonEmbedded2: "d",
+	}
+	err := LoadFromEnvironment(session, "", &testEmbedded,
+		defaults, filepath.Join(".", "fixtures", "nested-config-test.json"))
+	require.NoError(t, err)
+	assert.NotEmpty(t, testEmbedded.NonEmbedded1)
+	assert.Equal(t, "non-embedded 1", testEmbedded.NonEmbedded1)
+	assert.NotEmpty(t, testEmbedded.NonEmbedded2)
+	assert.Equal(t, "d", testEmbedded.NonEmbedded2)
+	assert.NotEmpty(t, testEmbedded.Embedded1)
+	assert.Equal(t, "embedded 1", testEmbedded.Embedded1)
+	assert.NotEmpty(t, testEmbedded.Embedded2)
+	assert.Equal(t, "embedded 2", testEmbedded.Embedded2)
+}
+
+// Config values loaded from env vars should be correctly mapped onto a struct that embeds another struct with no mapstructure tag set
+func TestEmbeddedServiceConfigurationWithNoTagLoadFromEnvironment(t *testing.T) {
+	os.Clearenv()
+	session := viper.New()
+	testEmbedded := TestCfgWithEmbeddedCfg{}
+	err := loadEnvIntoEnvironment(t, filepath.Join(".", "fixtures", "env-test.env"))
+	require.NoError(t, err)
+
+	err = LoadFromEnvironment(session, "WITH_NO_TAG", &testEmbedded,
+		&TestCfgWithEmbeddedCfg{}, "")
+	require.NoError(t, err)
+	assert.NotEmpty(t, testEmbedded.NonEmbedded1)
+	assert.Equal(t, "non-embedded 1", testEmbedded.NonEmbedded1)
+	assert.NotEmpty(t, testEmbedded.Embedded1)
+	assert.Equal(t, "embedded 1", testEmbedded.Embedded1)
+	assert.NotEmpty(t, testEmbedded.Embedded2)
+	assert.Equal(t, "embedded 2", testEmbedded.Embedded2)
+}
+
+// Config values loaded from env vars should be correctly mapped onto a struct that embeds another struct with a mapstructure tag set
+func TestEmbeddedServiceConfigurationWithTagLoadFromEnvironment(t *testing.T) {
+	os.Clearenv()
+	session := viper.New()
+	testEmbeddedWithTag := TestCfgWithEmbeddedCfgWithTag{}
+	err := loadEnvIntoEnvironment(t, filepath.Join(".", "fixtures", "env-test.env"))
+	require.NoError(t, err)
+
+	err = LoadFromEnvironment(session, "WITH_TAG", &testEmbeddedWithTag,
+		&TestCfgWithEmbeddedCfgWithTag{}, "")
+	require.NoError(t, err)
+	assert.NotEmpty(t, testEmbeddedWithTag.NonEmbedded1)
+	assert.Equal(t, "non-embedded 1", testEmbeddedWithTag.NonEmbedded1)
+	assert.NotEmpty(t, testEmbeddedWithTag.Embedded1)
+	assert.Equal(t, "embedded 1", testEmbeddedWithTag.Embedded1)
+	assert.NotEmpty(t, testEmbeddedWithTag.Embedded2)
+	assert.Equal(t, "embedded 2", testEmbeddedWithTag.Embedded2)
+}
+
+// Flat config values loaded from env vars should be correctly mapped onto a struct that embeds another struct with the ",squash" mapstructure tag set
+func TestEmbeddedServiceConfigurationWithSquashTagLoadFromEnvironment(t *testing.T) {
+	os.Clearenv()
+	session := viper.New()
+	testEmbeddedWithSquashTag := TestCfgWithEmbeddedCfgWithSquashTag{}
+	err := loadEnvIntoEnvironment(t, filepath.Join(".", "fixtures", "env-test.env"))
+	require.NoError(t, err)
+
+	err = LoadFromEnvironment(session, "WITH_SQUASH_TAG", &testEmbeddedWithSquashTag,
+		&TestCfgWithEmbeddedCfgWithSquashTag{}, "")
+	require.NoError(t, err)
+	assert.NotEmpty(t, testEmbeddedWithSquashTag.NonEmbedded1)
+	assert.Equal(t, "non-embedded 1", testEmbeddedWithSquashTag.NonEmbedded1)
+	assert.NotEmpty(t, testEmbeddedWithSquashTag.Embedded1)
+	assert.Equal(t, "embedded 1", testEmbeddedWithSquashTag.Embedded1)
+	assert.NotEmpty(t, testEmbeddedWithSquashTag.Embedded2)
+	assert.Equal(t, "embedded 2", testEmbeddedWithSquashTag.Embedded2)
+}
+
+func loadEnvIntoEnvironment(t *testing.T, envPath string) (err error) {
+	t.Helper()
+	_, err = fs.Stat(os.DirFS("."), envPath)
+	require.NoError(t, err)
+
+	err = godotenv.Load(envPath)
+	require.NoError(t, err)
+
+	return
+}