refactor(config): remove viper, replace with yaml.v3 + pflag + fsnotify

.golangci.yml

@@ -29,6 +29,10 @@ linters:
         - ok
         - fs
         - ca
+    tagliatelle:
+      case:
+        rules:
+          yaml: kebab
   exclusions:
     generated: lax
     presets:

go.mod

@@ -15,11 +15,9 @@ require (
 	github.com/gorilla/mux v1.8.1
 	github.com/hashicorp/go-multierror v1.1.1
 	github.com/hashicorp/go-version v1.9.0
-	github.com/mitchellh/mapstructure v1.5.0
 	github.com/samber/lo v1.53.0
 	github.com/spf13/afero v1.15.0
 	github.com/spf13/pflag v1.0.10
-	github.com/spf13/viper v1.21.0
 	github.com/stretchr/testify v1.11.1
 	github.com/xeipuuv/gojsonschema v1.2.0
 	github.com/yuin/gopher-lua v1.1.2
@@ -38,9 +36,7 @@ require (
 	github.com/clipperhouse/displaywidth v0.11.0 // indirect
 	github.com/clipperhouse/uax29/v2 v2.7.0 // indirect
 	github.com/gkampitakis/ciinfo v0.3.4 // indirect
-	github.com/go-viper/mapstructure/v2 v2.5.0 // indirect
 	github.com/goccy/go-yaml v1.19.2 // indirect
-	github.com/google/go-cmp v0.7.0 // indirect
 	github.com/hashicorp/errwrap v1.1.0 // indirect
 	github.com/kr/pretty v0.3.1 // indirect
 	github.com/kr/text v0.2.0 // indirect
@@ -49,7 +45,6 @@ require (
 	github.com/mattn/go-runewidth v0.0.23 // indirect
 	github.com/muesli/cancelreader v0.2.2 // indirect
 	github.com/rogpeppe/go-internal v1.14.1 // indirect
-	github.com/sagikazarmark/locafero v0.12.0 // indirect
 	github.com/sergi/go-diff v1.4.0 // indirect
 	github.com/tidwall/gjson v1.18.0 // indirect
 	github.com/tidwall/match v1.2.0 // indirect
@@ -58,18 +53,14 @@ require (
 	github.com/xeipuuv/gojsonpointer v0.0.0-20190905194746-02993c407bfb // indirect
 	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect
 	github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e // indirect
-	go.yaml.in/yaml/v3 v3.0.4 // indirect
 	golang.org/x/sync v0.20.0 // indirect
 )
 
 require (
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/fsnotify/fsnotify v1.10.0
-	github.com/pelletier/go-toml/v2 v2.3.1 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/rivo/uniseg v0.4.7 // indirect
-	github.com/spf13/cast v1.10.0 // indirect
-	github.com/subosito/gotenv v1.6.0 // indirect
 	golang.org/x/exp v0.0.0-20260410095643-746e56fc9e2f // indirect
 	golang.org/x/sys v0.43.0 // indirect
 	golang.org/x/text v0.36.0 // indirect

go.sum

@@ -39,8 +39,6 @@ github.com/dgryski/go-farm v0.0.0-20240924180020-3414d57e47da h1:aIftn67I1fkbMa5
 github.com/dgryski/go-farm v0.0.0-20240924180020-3414d57e47da/go.mod h1:SqUrOPUnsFjfmXRMNPybcSiG0BgUW2AuFH8PAnS2iTw=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
-github.com/frankban/quicktest v1.14.6 h1:7Xjx+VpznH+oBnejlPUj8oUpdxnVs4f8XU8WnHkI4W8=
-github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
 github.com/fsnotify/fsnotify v1.10.0 h1:Xx/5Ydg9CeBDX/wi4VJqStNtohYjitZhhlHt4h3St1M=
 github.com/fsnotify/fsnotify v1.10.0/go.mod h1:TLheqan6HD6GBK6PrDWyDPBaEV8LspOxvPSjC+bVfgo=
 github.com/gkampitakis/ciinfo v0.3.4 h1:5eBSibVuSMbb/H6Elc0IIEFbkzCJi3lm94n0+U7Z0KY=
@@ -49,14 +47,10 @@ github.com/gkampitakis/go-snaps v0.5.21 h1:SvhSFeZviQXwlT+dnGyAIATVehkhqRVW6qfQZ
 github.com/gkampitakis/go-snaps v0.5.21/go.mod h1:gC3YqxQTPyIXvQrw/Vpt3a8VqR1MO8sVpZFWN4DGwNs=
 github.com/go-http-utils/headers v0.0.0-20181008091004-fed159eddc2a h1:v6zMvHuY9yue4+QkG/HQ/W67wvtQmWJ4SDo9aK/GIno=
 github.com/go-http-utils/headers v0.0.0-20181008091004-fed159eddc2a/go.mod h1:I79BieaU4fxrw4LMXby6q5OS9XnoR9UIKLOzDFjUmuw=
-github.com/go-viper/mapstructure/v2 v2.5.0 h1:vM5IJoUAy3d7zRSVtIwQgBj7BiWtMPfmPEgAXnvj1Ro=
-github.com/go-viper/mapstructure/v2 v2.5.0/go.mod h1:oJDH3BJKyqBA2TXFhDsKDGDTlndYOZ6rGS0BRZIxGhM=
 github.com/goccy/go-yaml v1.19.2 h1:PmFC1S6h8ljIz6gMRBopkjP1TVT7xuwrButHID66PoM=
 github.com/goccy/go-yaml v1.19.2/go.mod h1:XBurs7gK8ATbW4ZPGKgcbrY1Br56PdM69F7LkFRi1kA=
 github.com/gojuno/minimock/v3 v3.4.7 h1:vhE5zpniyPDRT0DXd5s3DbtZJVlcbmC5k80izYtj9lY=
 github.com/gojuno/minimock/v3 v3.4.7/go.mod h1:QxJk4mdPrVyYUmEZGc2yD2NONpqM/j4dWhsy9twjFHg=
-github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
-github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
 github.com/gorilla/mux v1.8.1 h1:TuBL49tXwgrFYWhqrNgrUNEY92u81SPhu7sTdzQEiWY=
 github.com/gorilla/mux v1.8.1/go.mod h1:AKf9I4AEqPTmMytcMc0KkNouC66V3BtZ4qD5fmWSiMQ=
 github.com/hashicorp/errwrap v1.0.0/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=
@@ -79,12 +73,8 @@ github.com/maruel/natural v1.3.0 h1:VsmCsBmEyrR46RomtgHs5hbKADGRVtliHTyCOLFBpsg=
 github.com/maruel/natural v1.3.0/go.mod h1:v+Rfd79xlw1AgVBjbO0BEQmptqb5HvL/k9GRHB7ZKEg=
 github.com/mattn/go-runewidth v0.0.23 h1:7ykA0T0jkPpzSvMS5i9uoNn2Xy3R383f9HDx3RybWcw=
 github.com/mattn/go-runewidth v0.0.23/go.mod h1:XBkDxAl56ILZc9knddidhrOlY5R/pDhgLpndooCuJAs=
-github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyuac5Z2hdY=
-github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
 github.com/muesli/cancelreader v0.2.2 h1:3I4Kt4BQjOR54NavqnDogx/MIoWBFa0StPA8ELUXHmA=
 github.com/muesli/cancelreader v0.2.2/go.mod h1:3XuTXfFS2VjM+HTLZY9Ak0l6eUKfijIfMUZ4EgX0QYo=
-github.com/pelletier/go-toml/v2 v2.3.1 h1:MYEvvGnQjeNkRF1qUuGolNtNExTDwct51yp7olPtrEc=
-github.com/pelletier/go-toml/v2 v2.3.1/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
 github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRIccs7FGNTlIRMkT8wgtp5eCXdBlqhYGL6U=
@@ -94,27 +84,19 @@ github.com/rivo/uniseg v0.4.7/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUc
 github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
 github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0tI/otEQ=
 github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7so1lCWt35ZSgc=
-github.com/sagikazarmark/locafero v0.12.0 h1:/NQhBAkUb4+fH1jivKHWusDYFjMOOKU88eegjfxfHb4=
-github.com/sagikazarmark/locafero v0.12.0/go.mod h1:sZh36u/YSZ918v0Io+U9ogLYQJ9tLLBmM4eneO6WwsI=
 github.com/samber/lo v1.53.0 h1:t975lj2py4kJPQ6haz1QMgtId2gtmfktACxIXArw3HM=
 github.com/samber/lo v1.53.0/go.mod h1:4+MXEGsJzbKGaUEQFKBq2xtfuznW9oz/WrgyzMzRoM0=
 github.com/sergi/go-diff v1.4.0 h1:n/SP9D5ad1fORl+llWyN+D6qoUETXNZARKjyY2/KVCw=
 github.com/sergi/go-diff v1.4.0/go.mod h1:A0bzQcvG0E7Rwjx0REVgAGH58e96+X0MeOfepqsbeW4=
 github.com/spf13/afero v1.15.0 h1:b/YBCLWAJdFWJTN9cLhiXXcD7mzKn9Dm86dNnfyQw1I=
 github.com/spf13/afero v1.15.0/go.mod h1:NC2ByUVxtQs4b3sIUphxK0NioZnmxgyCrfzeuq8lxMg=
-github.com/spf13/cast v1.10.0 h1:h2x0u2shc1QuLHfxi+cTJvs30+ZAHOGRic8uyGTDWxY=
-github.com/spf13/cast v1.10.0/go.mod h1:jNfB8QC9IA6ZuY2ZjDp0KtFO2LZZlg4S/7bzP6qqeHo=
 github.com/spf13/pflag v1.0.10 h1:4EBh2KAYBwaONj6b2Ye1GiHfwjqyROoF4RwYO+vPwFk=
 github.com/spf13/pflag v1.0.10/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
-github.com/spf13/viper v1.21.0 h1:x5S+0EU27Lbphp4UKm1C+1oQO+rKx36vfCoaVebLFSU=
-github.com/spf13/viper v1.21.0/go.mod h1:P0lhsswPGWD/1lZJ9ny3fYnVqxiegrlNrEmgLjbTCAY=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
-github.com/subosito/gotenv v1.6.0 h1:9NlTDc1FTs4qu0DDq7AEtTPNw6SVm7uBMsUCUjABIf8=
-github.com/subosito/gotenv v1.6.0/go.mod h1:Dk4QP5c2W3ibzajGcXpNraDfq2IrhjMIvMSWPKKo0FU=
 github.com/tidwall/gjson v1.14.2/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
 github.com/tidwall/gjson v1.18.0 h1:FIDeeyB800efLX89e5a8Y0BNH+LOngJyGrIWxG2FKQY=
 github.com/tidwall/gjson v1.18.0/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
@@ -137,8 +119,6 @@ github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e h1:JVG44RsyaB9T2KIHavM
 github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e/go.mod h1:RbqR21r5mrJuqunuUZ/Dhy/avygyECGrLceyNeo4LiM=
 github.com/yuin/gopher-lua v1.1.2 h1:yF/FjE3hD65tBbt0VXLE13HWS9h34fdzJmrWRXwobGA=
 github.com/yuin/gopher-lua v1.1.2/go.mod h1:7aRmXIWl37SqRf0koeyylBEzJ+aPt8A+mmkQ4f1ntR8=
-go.yaml.in/yaml/v3 v3.0.4 h1:tfq32ie2Jv2UxXFdLJdh3jXuOzWiL1fo0bu/FbuKpbc=
-go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
 golang.org/x/exp v0.0.0-20260410095643-746e56fc9e2f h1:W3F4c+6OLc6H2lb//N1q4WpJkhzJCK5J6kUi1NTVXfM=
 golang.org/x/exp v0.0.0-20260410095643-746e56fc9e2f/go.mod h1:J1xhfL/vlindoeF/aINzNzt2Bket5bjo9sdOYzOsU80=
 golang.org/x/net v0.53.0 h1:d+qAbo5L0orcWAr0a9JweQpjXF19LMXJE8Ey7hwOdUA=

internal/config/cache_config.go

@@ -1,9 +1,17 @@
 package config
 
 import (
+	"errors"
+	"fmt"
+	"strings"
 	"time"
+
+	"gopkg.in/yaml.v3"
 )
 
+// ErrInvalidCacheConfig is returned when the cache-config YAML value is not a mapping.
+var ErrInvalidCacheConfig = errors.New("expected a mapping for cache-config")
+
 type CacheGlobs []string
 
 func (g CacheGlobs) Clone() CacheGlobs {
@@ -18,9 +26,9 @@ func (g CacheGlobs) Clone() CacheGlobs {
 }
 
 type CacheConfig struct {
-	ExpirationTime time.Duration `mapstructure:"expiration-time"`
-	MaxSize        int64         `mapstructure:"max-size"`
-	Methods        []string      `mapstructure:"methods"`
+	ExpirationTime time.Duration `yaml:"-"`
+	MaxSize        int64         `yaml:"max-size"`
+	Methods        []string      `yaml:"methods"`
 }
 
 func (c *CacheConfig) Clone() *CacheConfig {
@@ -35,3 +43,41 @@ func (c *CacheConfig) Clone() *CacheConfig {
 		Methods:        methods,
 	}
 }
+
+// UnmarshalYAML implements custom decoding so that the "expiration-time" field
+// can be expressed as a human-readable duration string (e.g. "30m", "1h").
+// Other fields are decoded by the standard yaml.v3 machinery.
+// Only fields present in the YAML node are updated; existing values (defaults)
+// are preserved for absent keys.
+func (c *CacheConfig) UnmarshalYAML(value *yaml.Node) error {
+	if value.Kind != yaml.MappingNode {
+		return ErrInvalidCacheConfig
+	}
+
+	for i := 0; i+1 < len(value.Content); i += 2 {
+		keyNode := value.Content[i]
+		valNode := value.Content[i+1]
+
+		switch keyNode.Value {
+		case "expiration-time":
+			dur, err := time.ParseDuration(strings.ReplaceAll(valNode.Value, " ", ""))
+			if err != nil {
+				return fmt.Errorf("invalid expiration-time %q: %w", valNode.Value, err)
+			}
+
+			c.ExpirationTime = dur
+		case "max-size":
+			err := valNode.Decode(&c.MaxSize)
+			if err != nil {
+				return err
+			}
+		case "methods":
+			err := valNode.Decode(&c.Methods)
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}

internal/config/cache_config_test.go

@@ -7,8 +7,69 @@ import (
 
 	"github.com/evg4b/uncors/internal/config"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"gopkg.in/yaml.v3"
 )
 
+func TestCacheConfigUnmarshalYAML(t *testing.T) {
+	t.Run("decodes all fields", func(t *testing.T) {
+		const input = `
+expiration-time: 30m
+max-size: 52428800
+methods:
+  - GET
+  - POST
+`
+
+		var actual config.CacheConfig
+
+		require.NoError(t, yaml.Unmarshal([]byte(input), &actual))
+		assert.Equal(t, config.CacheConfig{
+			ExpirationTime: 30 * time.Minute,
+			MaxSize:        52428800,
+			Methods:        []string{http.MethodGet, http.MethodPost},
+		}, actual)
+	})
+
+	t.Run("parses expiration-time with embedded spaces", func(t *testing.T) {
+		const input = `expiration-time: "1h 30m"`
+
+		var actual config.CacheConfig
+
+		require.NoError(t, yaml.Unmarshal([]byte(input), &actual))
+		assert.Equal(t, 90*time.Minute, actual.ExpirationTime)
+	})
+
+	t.Run("absent fields keep zero values", func(t *testing.T) {
+		const input = `max-size: 1024`
+
+		var actual config.CacheConfig
+
+		require.NoError(t, yaml.Unmarshal([]byte(input), &actual))
+		assert.Equal(t, int64(1024), actual.MaxSize)
+		assert.Zero(t, actual.ExpirationTime)
+		assert.Nil(t, actual.Methods)
+	})
+
+	t.Run("returns ErrInvalidCacheConfig for non-mapping node", func(t *testing.T) {
+		const input = `- item1`
+
+		var actual config.CacheConfig
+
+		err := yaml.Unmarshal([]byte(input), &actual)
+
+		assert.ErrorIs(t, err, config.ErrInvalidCacheConfig)
+	})
+
+	t.Run("returns error for invalid expiration-time", func(t *testing.T) {
+		const input = `expiration-time: not-a-duration`
+
+		var actual config.CacheConfig
+
+		assert.Error(t, yaml.Unmarshal([]byte(input), &actual))
+	})
+}
+
 func TestCacheGlobsClone(t *testing.T) {
 	globs := config.CacheGlobs{
 		"/api/**",