README
¶
validate
Composable validation for Go with fluent builders, rule tags, struct validation, and optional message translation.
Packages
github.com/aatuh/validate/v3: main API (Validate, builders,FromTag)github.com/aatuh/validate/v3/core: generic validation engine (unified, cache-optimized)github.com/aatuh/validate/v3/glue: integration layer with buildersgithub.com/aatuh/validate/v3/validators: type-specific rulesgithub.com/aatuh/validate/v3/errors: error types and codesgithub.com/aatuh/validate/v3/structvalidator: struct validationgithub.com/aatuh/validate/v3/translator: i18n helpers
The package is architecturally separated into:
- Core: Generic validation engine, type-agnostic, with unified caching
- Glue: Integration layer that connects core with type-specific builders
- Validators: Type-specific validation implementations
Quick start
For examples, see the examples package.
Run examples:
# Run all examples in learning order
go test ./examples -v -count 1
# Run specific examples
go test ./examples -v -count 1 -run Test_structTags
Supported data types
| Type | Description |
|---|---|
| string | UTF-8 strings; rune-aware length rules |
| int | Any Go int type accepted at call time |
| int64 | Requires exactly int64 at call time |
| slice | Any slice type; supports per-element |
| bool | Boolean type-check only |
Plugin rules that operate on strings (imported by default):
- uuid: validates canonical UUID string
- ulid: validates ULID string
- email: validates email address string
Note on plugin registration:
validate.New()already registers these plugin validators via blank imports inside the root package.- If you use
core/gluedirectly, blank-import the plugins yourself:
import (
_ "github.com/aatuh/validate/v3/validators/email"
_ "github.com/aatuh/validate/v3/validators/ulid"
_ "github.com/aatuh/validate/v3/validators/uuid"
)
Tags by type
Tags can be used in struct field tags or with FromTag.
string
| Tag | Meaning |
|---|---|
| len=N | Exact byte length equals N |
| min=N | Minimum byte length |
| max=N | Maximum byte length |
| minRunes=N | Minimum Unicode rune count |
| maxRunes=N | Maximum Unicode rune count |
| oneof=a,b,c | Value must be one of the listed values |
| regex=PATTERN | Full-match against PATTERN (anchors added) |
| uuid | UUID format (via plugin) |
| ulid | ULID format (via plugin) |
| Email format (via plugin) |
Notes:
oneofsupports comma or space separated values.- Regex is made safe (anchors added, input length capped).
int / int64
| Tag | Meaning |
|---|---|
| min=N | Minimum numeric value |
| max=N | Maximum numeric value |
Use int64;... to require exactly int64 at validation time; int;...
accepts any Go int type (int, int8, int16, int32, int64, and
unsigned variants for base type checks).
slice
| Tag | Meaning |
|---|---|
| len=N | Exact slice length |
| min=N | Minimum slice length |
| max=N | Maximum slice length |
| foreach=(...) | Element rules in parentheses, e.g. string rules |
Example: slice;min=1;foreach=(string;min=2).
bool
| Tag | Meaning |
|---|---|
| bool | Type check (boolean) |
Error codes
Stable constants for programmatic handling (see errors/codes.go):
const (
// String
CodeStringMin = "string.min"
CodeStringMax = "string.max"
CodeStringNonEmpty = "string.nonempty"
CodeStringPattern = "string.pattern"
CodeStringOneOf = "string.oneof"
// Number (ints/floats)
CodeNumberMin = "number.min"
CodeNumberMax = "number.max"
// Slice
CodeSliceMin = "slice.min"
CodeSliceMax = "slice.max"
)
Documentation
¶
Overview ¶
Package validate provides composable validation helpers for Go with fluent builders, rule tags, and struct validation. It includes optional message translation support.
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func ValidateStruct ¶ added in v3.0.3
ValidateStruct validates a struct using v (or a fresh instance).
Types ¶
type BoolBuilder ¶
type BoolBuilder = glue.BoolBuilder
type CustomTypeBuilder ¶ added in v3.0.3
type CustomTypeBuilder = glue.CustomTypeBuilder
type IntBuilder ¶
type IntBuilder = glue.IntBuilder
type SliceBuilder ¶
type SliceBuilder = glue.SliceBuilder
type StringBuilder ¶
type StringBuilder = glue.StringBuilder
type Validate ¶
Re-export types for a developer-friendly root facade.
func New ¶
func New() *Validate
New returns a Validate configured with sensible defaults.
Defaults: - Installs default English translations via SimpleTranslator. - Registers built-in plugins (email, ulid, uuid) via blank imports.
func NewBare ¶
func NewBare() *Validate
NewBare returns a Validate without installing a default translator. Useful for advanced setups that manage translations differently.
func NewWithTranslator ¶
func NewWithTranslator(tr translator.Translator) *Validate
NewWithTranslator returns a Validate configured with the provided translator while keeping other defaults.
Source Files
Directories
¶
| Path | Synopsis |
|---|---|
|
Package core provides the main validation engine and fluent builder APIs.
|
Package core provides the main validation engine and fluent builder APIs. |
|
Package errors provides error types and error handling utilities for validation.
|
Package errors provides error types and error handling utilities for validation. |
|
Package examples provides examples for the validate package.
|
Package examples provides examples for the validate package. |
|
Package structvalidator provides struct validation functionality using reflection.
|
Package structvalidator provides struct validation functionality using reflection. |
|
Package translator provides internationalization support for validation messages.
|
Package translator provides internationalization support for validation messages. |
|
Package types provides the core validation engine types and rule system.
|
Package types provides the core validation engine types and rule system. |
|
Package validators provides built-in validation rules and plugin architecture.
|
Package validators provides built-in validation rules and plugin architecture. |
|
email
Package email provides email address validation as a plugin.
|
Package email provides email address validation as a plugin. |
|
ulid
Package ulid provides ULID validation as a plugin.
|
Package ulid provides ULID validation as a plugin. |
|
uuid
Package uuid provides UUID validation as a plugin.
|
Package uuid provides UUID validation as a plugin. |