Add string slice support

AGENTS.md

@@ -0,0 +1,48 @@
+# AGENTS.md
+
+## Commands
+- Build: `go build ./...`
+- Test all: `go test ./...`
+- Test single: `go test -run TestName ./...`
+- Lint: `golangci-lint run ./...`
+- Format touched Go files with `gofmt`/`goimports`; the linter also enables `gci`, `gofmt`, `gofumpt`, and `goimports` formatters.
+
+## Repo Architecture
+- This is a single-package Go module: `github.com/tilebox/structconf`.
+- `structconf.go`: Public loading API (`Load`, `LoadArgs`, `MustLoad`, `MustLoadArgs`), functional options, subcommand helpers (`BindCommand`, `NewCommand`), duplicate flag detection, and the two-pass TOML load flow.
+- `config.go`: Reflection-based struct walker that turns exported struct fields into `urfave/cli/v3` flags and applies parsed values back into the config struct.
+- `tags.go`: Struct tag parsing and default name derivation for flags, env vars, TOML/YAML/JSON keys, aliases, global fields, secrets, defaults, and help text.
+- `toml.go`: TOML file loading and `cli.ValueSource` adapters used to feed TOML values into the same precedence chain as env vars/defaults.
+- `validate.go`: Default validation using `go-playground/validator/v10`, with user-facing error messages.
+- `marshal.go`: Config marshaling helpers (`MarshalAsMap`, `MarshalAsSlogDict`) and secret redaction.
+- `examples`: Runnable examples for each major feature; keep examples small and aligned with README snippets.
+
+## Core Behavior And Contracts
+- Source precedence is CLI flags first, then TOML config files, then environment variables, then `default` tags.
+- Exported fields get generated names by default: kebab-case flags/TOML/YAML keys, screaming snake env vars, and lower camel JSON names.
+- Nested structs compose parent names unless a field is tagged `global:"true"`.
+- Fields tagged `flag:"-"` are not configurable; analogous `env:"-"` and `toml:"-"` disable those sources.
+- Supported config field types are `string`, `[]string`, signed/unsigned integer widths, floats, `bool`, and `time.Duration`.
+- `LoadArgs`/`BindCommand` run validation after values are applied; custom validators replace the default validator.
+
+## Design Patterns And Paradigms
+- Public APIs use functional options (`WithVersion`, `WithDescription`, `WithValidator`, etc.).
+- Keep the reflection pipeline centralized in `NewStructConfigurator`, `recurseStruct`, and `processField`; avoid one-off parsing paths that bypass the shared value-source precedence behavior.
+- Prefer adding behavior at the source of truth (`config.go`, `tags.go`, or `toml.go`) rather than wrapping public APIs for special cases.
+- Return errors with useful context and `%w` when wrapping underlying failures.
+- Keep generated CLI help/error text stable where tests assert on it.
+
+## Code Style
+- Use `stretchr/testify` (`require` for setup/fatal checks, `assert` for value comparisons).
+- Prefer table-driven tests for multi-source or multi-type behavior.
+- Keep imports grouped and formatted by Go tooling.
+- Respect struct tag order enforced by lint: `flag`, `env`, `default`, `secret`, `toml`, `json`, `validate`, `global`, `help`.
+- Avoid new package-level globals and `init` functions unless there is a strong reason; `tags.go` currently has an intentional `init` for `strcase` initialism configuration.
+- Examples may print to stdout; library code should not, except for existing `MustLoad*` error/help handling.
+
+## Typical Development Flow
+1. Make the smallest focused change in the root package and update README/examples/changelog when behavior changes.
+2. Add or update focused tests in `structconf_test.go` for precedence, tag handling, validation, or CLI behavior.
+3. Run `go test ./...` for behavior changes.
+4. Run `go build ./...` when examples or public APIs change.
+5. Run `golangci-lint run ./...` before handing off larger changes or anything likely to touch lint-sensitive code.

CHANGELOG.md

@@ -0,0 +1,45 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [0.4.0] - 2026-05-20
+
+### Added
+
+- Added support for configuring `[]string` fields from comma-separated CLI flags, environment variables, and default values, plus native TOML string arrays.
+
+## [0.3.0] - 2026-05-12
+
+### Added
+
+- Added custom validator registration via `WithValidateFunc`.
+
+## [0.2.0] - 2026-03-13
+
+### Added
+
+- Added composable command binding helpers for subcommand CLIs via `BindCommand` and `NewCommand`.
+- Added a subcommands example.Now
+
+## [0.1.0] - 2026-01-02
+
+### Added
+
+- Added initial struct tag based configuration loading from CLI flags, environment variables, TOML config files, and default values.
+- Added support for nested structs, field tags, generated help output, validation, and marshaling.
+- Added examples covering basic CLI usage, defaults, nested structs, TOML loading, overrides, globals, marshaling, and validation.
+
+### Fixed
+
+- Fixed integer parsing to use the correct bit size for signed and unsigned integer fields.
+
+[Unreleased]: https://github.com/tilebox/structconf/compare/v0.4.0...HEAD
+[0.4.0]: https://github.com/tilebox/structconf/compare/v0.3.0...v0.4.0
+[0.3.0]: https://github.com/tilebox/structconf/compare/v0.2.0...v0.3.0
+[0.2.0]: https://github.com/tilebox/structconf/compare/v0.1.0...v0.2.0
+[0.1.0]: https://github.com/tilebox/structconf/releases/tag/v0.1.0

README.md

@@ -14,7 +14,7 @@ go get github.com/tilebox/structconf
   - Order of precedence: CLI flags, config files, environment variables, default values
 - By only defining a struct containing all the fields you want to configure
 - Structs can be nested within other structs
-- Supported data types: `string`, `int`, `int8-64`, `uint`, `uint8-64`, `bool`, `float`, `time.Duration`
+- Supported data types: `string`, `[]string`, `int`, `int8-64`, `uint`, `uint8-64`, `bool`, `float`, `time.Duration`
 - Customize certain fields by adding tags to the struct fields
   - Using the tags `flag`, `env`, `default`, `secret`, `toml`, `validate`, `global`, `help`
 - Includes input validation using [go-playground/validator](https://github.com/go-playground/validator)
@@ -202,6 +202,32 @@ $ ./app --load-config database.toml
 &{INFO {myuser mypassword}}
 ```
 
+### Configure string slices
+
+`[]string` fields are configured with comma-separated values from CLI flags, environment variables and default values.
+When loading from TOML, native string arrays are supported as well.
+
+```go
+type AppConfig struct {
+    AllowedOrigins []string `flag:"allowed-origins" env:"ALLOWED_ORIGINS" toml:"allowed-origins" help:"Allowed CORS origins"`
+}
+
+func main() {
+    cfg := &AppConfig{}
+    structconf.MustLoad(cfg, "app", structconf.WithLoadConfigFlag("load-config"))
+}
+```
+
+```bash
+$ ./app --allowed-origins=https://app.example.com,https://admin.example.com
+$ ALLOWED_ORIGINS=https://app.example.com,https://admin.example.com ./app
+```
+
+```toml
+# app.toml
+allowed-origins = ["https://app.example.com", "https://admin.example.com"]
+```
+
 ### Build subcommands
 
 You can bind configs directly to `urfave/cli` commands and compose them as subcommands.
@@ -406,6 +432,9 @@ type AppConfig struct {
 
     // must be one of (case insensitive): DEBUG, INFO, WARN, ERROR 
     LogLevel string `default:"INFO" validate:"oneofci=DEBUG INFO WARN ERROR" help:"Log level"`
+
+    // if set, each comma-separated value must be one of (case insensitive): password, oauth, saml, magic_link
+    EnabledAuthProviders []string `validate:"omitempty,dive,oneofci=password oauth saml magic_link" help:"Enabled authentication providers"`
 }
 
 func main() {

config.go

@@ -91,6 +91,29 @@ func (r *structReflector) processField(field reflect.StructField, fieldValue ref
 		apply = func(cmd *cli.Command) {
 			fieldValue.SetString(cmd.String(flagName))
 		}
+	case reflect.Slice:
+		if field.Type.Elem().Kind() != reflect.String {
+			return fmt.Errorf("unsupported slice element type %s for field %s", field.Type.Elem().Kind(), field.Name)
+		}
+
+		flag = &cli.StringFlag{
+			Name:        flagName,
+			Aliases:     tags.aliases,
+			Usage:       tags.help,
+			DefaultText: tags.defaultValue,
+			Value:       tags.defaultValue,
+			Sources:     sources,
+		}
+
+		apply = func(cmd *cli.Command) {
+			value := cmd.String(flagName)
+			if value == "" {
+				fieldValue.Set(reflect.Zero(field.Type))
+				return
+			}
+
+			fieldValue.Set(reflect.ValueOf(strings.Split(value, ",")))
+		}
 	case reflect.Int:
 		var value int
 		if tags.defaultValue != "" {

examples/10_slices/main.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/tilebox/structconf"
+)
+
+type AppConfig struct {
+	AllowedOrigins []string `flag:"allowed-origins" env:"ALLOWED_ORIGINS" toml:"allowed-origins" validate:"omitempty,dive,url" help:"comma-separated list of allowed CORS origins"`
+}
+
+// usage: ./app --allowed-origins=https://app.example.com,https://admin.example.com
+// or: ALLOWED_ORIGINS=https://app.example.com,https://admin.example.com ./app
+// or with TOML: allowed-origins = ["https://app.example.com", "https://admin.example.com"]
+func main() {
+	cfg := &AppConfig{}
+	structconf.MustLoad(cfg, "app", structconf.WithVersion("1.0.0"), structconf.WithLoadConfigFlag("load-config"))
+
+	fmt.Printf("%v\n", cfg.AllowedOrigins)
+}