validate

Input validation made easy for Go interface methods.

Installation

Make a custom build of protogo:

$ protogo build --plugin=github.com/protogodev/validate

Or build from a local fork:

$ protogo build --plugin=github.com/protogodev/validate=../my-fork

Usage

$ protogo validate -h
Usage: protogo validate <source-file> <interface-name>

Arguments:
  <source-file>       source file
  <interface-name>    interface name

Flags:
  -h, --help             Show context-sensitive help.

      --out="."          output directory
      --fmt              whether to make the generated code formatted
      --custom=STRING    the declaration file of custom validators

Quick Start

NOTE: The following code is located in helloworld.

1. Define the interface

   type Service interface {
       SayHello(ctx context.Context, name string) (message string, err error)
   }

2. Implement the service

   type Greeter struct{}
   
   func (g *Greeter) SayHello(ctx context.Context, name string) (string, error) {
       return "Hello " + name, nil
   }

3. Add the validation annotations

   type Service interface {
       // @schema:
       //   name: len(0, 10) && match(`^\w+$`)
       SayHello(ctx context.Context, name string) (message string, err error)
   }

4. Generate the validation middleware

   $ cd examples/helloworld
   $ protogo validate ./service.go Service

5. Use the middleware for input validation

   func main() {
       var svc helloworld.Service = &helloworld.Greeter{}
       svc = helloworld.ValidateMiddleware(nil)(svc)
   
       message, err = svc.SayHello(context.Background(), "!Tracey")
       fmt.Printf("message: %q, err: %v\n", message, err)
   
       // Output:
       // message: "", err: name: INVALID(invalid format)
   }

Validation Syntax

Operator / Validator	Validating / Vext Equivalent(s)	Example
!	Not	!lt(0)
&&	All / And	gt(0) && lt(10)
||	Any / Or	eq(0) || eq(1)
nonzero	Nonzero	nonzero
zero	Zero	zero
len	LenString / LenSlice	len(0, 10)
runecnt	RuneCount	runecnt(0, 10)
eq	Eq	eq(1)
ne	Ne	ne(2)
gt	Gt	gt(0)
gte	Gte	gte(0)
lt	Lt	lt(10)
lte	Lte	lte(10)
xrange	Range	xrange(0, 10)
in	In	in(0, 1)
nin	Nin	nin("Y", "N")
match	Match	match(`^\w+$`)
email	Email	email
ip	IP	ip
time	Time	time("2006-01-02T15:04:05Z07:00")
_	A special validator that means to use the nested Schema() of the struct argument.	_

Examples

See examples.

Documentation

Check out the documentation.

License

MIT