feat(pprof): add pprof HTTP server (#807)

- `PPROF_ENABLED=no`
- `PPROF_BLOCK_PROFILE_RATE=0`
- `PPROF_MUTEX_PROFILE_RATE=0`
- `PPROF_HTTP_SERVER_ADDRESS=":6060"`

internal/httpserver/settings_test.go

@@ -0,0 +1,330 @@
+package httpserver
+
+import (
+	"net/http"
+	"testing"
+	"time"
+
+	"github.com/qdm12/govalid/address"
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_Settings_SetDefaults(t *testing.T) {
+	t.Parallel()
+
+	const defaultTimeout = 3 * time.Second
+
+	testCases := map[string]struct {
+		settings Settings
+		expected Settings
+	}{
+		"empty settings": {
+			settings: Settings{},
+			expected: Settings{
+				Name:            stringPtr(""),
+				Address:         ":8000",
+				ShutdownTimeout: durationPtr(defaultTimeout),
+			},
+		},
+		"filled settings": {
+			settings: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+			expected: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			testCase.settings.SetDefaults()
+
+			assert.Equal(t, testCase.expected, testCase.settings)
+		})
+	}
+}
+
+func Test_Settings_Copy(t *testing.T) {
+	t.Parallel()
+
+	someHandler := http.NewServeMux()
+	someLogger := &testLogger{}
+
+	testCases := map[string]struct {
+		settings Settings
+		expected Settings
+	}{
+		"empty settings": {},
+		"filled settings": {
+			settings: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+			expected: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			copied := testCase.settings.Copy()
+
+			assert.Equal(t, testCase.expected, copied)
+		})
+	}
+}
+
+func Test_Settings_MergeWith(t *testing.T) {
+	t.Parallel()
+
+	someHandler := http.NewServeMux()
+	someLogger := &testLogger{}
+
+	testCases := map[string]struct {
+		settings Settings
+		other    Settings
+		expected Settings
+	}{
+		"merge empty with empty": {},
+		"merge empty with filled": {
+			other: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+			expected: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+		},
+		"merge filled with empty": {
+			settings: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+			expected: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			testCase.settings.MergeWith(testCase.other)
+
+			assert.Equal(t, testCase.expected, testCase.settings)
+		})
+	}
+}
+
+func Test_Settings_OverrideWith(t *testing.T) {
+	t.Parallel()
+
+	someHandler := http.NewServeMux()
+	someLogger := &testLogger{}
+
+	testCases := map[string]struct {
+		settings Settings
+		other    Settings
+		expected Settings
+	}{
+		"override empty with empty": {},
+		"override empty with filled": {
+			other: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+			expected: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+		},
+		"override filled with empty": {
+			settings: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+			expected: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+		},
+		"override filled with filled": {
+			settings: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8001",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+			other: Settings{
+				Name:            stringPtr("name2"),
+				Address:         ":8002",
+				ShutdownTimeout: durationPtr(time.Hour),
+			},
+			expected: Settings{
+				Name:            stringPtr("name2"),
+				Address:         ":8002",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Hour),
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			testCase.settings.OverrideWith(testCase.other)
+
+			assert.Equal(t, testCase.expected, testCase.settings)
+		})
+	}
+}
+
+func Test_Settings_Validate(t *testing.T) {
+	t.Parallel()
+
+	someHandler := http.NewServeMux()
+	someLogger := &testLogger{}
+
+	testCases := map[string]struct {
+		settings   Settings
+		errWrapped error
+		errMessage string
+	}{
+		"bad address": {
+			settings: Settings{
+				Address: "noport",
+			},
+			errWrapped: address.ErrValueNotValid,
+			errMessage: "value is not valid: address noport: missing port in address",
+		},
+		"nil handler": {
+			settings: Settings{
+				Address: ":8000",
+			},
+			errWrapped: ErrHandlerIsNotSet,
+			errMessage: ErrHandlerIsNotSet.Error(),
+		},
+		"nil logger": {
+			settings: Settings{
+				Address: ":8000",
+				Handler: someHandler,
+			},
+			errWrapped: ErrLoggerIsNotSet,
+			errMessage: ErrLoggerIsNotSet.Error(),
+		},
+		"shutdown timeout too small": {
+			settings: Settings{
+				Address:         ":8000",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Millisecond),
+			},
+			errWrapped: ErrShutdownTimeoutTooSmall,
+			errMessage: "shutdown timeout is too small: 1ms must be at least 5ms",
+		},
+		"valid settings": {
+			settings: Settings{
+				Address:         ":8000",
+				Handler:         someHandler,
+				Logger:          someLogger,
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			err := testCase.settings.Validate()
+
+			assert.ErrorIs(t, err, testCase.errWrapped)
+			if err != nil {
+				assert.EqualError(t, err, testCase.errMessage)
+			}
+		})
+	}
+}
+
+func Test_Settings_String(t *testing.T) {
+	t.Parallel()
+
+	testCases := map[string]struct {
+		settings Settings
+		s        string
+	}{
+		"all values": {
+			settings: Settings{
+				Name:            stringPtr("name"),
+				Address:         ":8000",
+				ShutdownTimeout: durationPtr(time.Second),
+			},
+			s: `Name HTTP server settings:
+├── Listening address: :8000
+└── Shutdown timeout: 1s`,
+		},
+	}
+
+	for name, testCase := range testCases {
+		testCase := testCase
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+
+			s := testCase.settings.String()
+
+			assert.Equal(t, testCase.s, s)
+		})
+	}
+}