Package validator

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Package validator implements value validations for structs and individual fields based on tags.

It has the following unique features:

• Cross Field and Cross Struct validations by using validation tags or custom validators.
• Slice, Array and Map diving, which allows any or all levels of a multidimensional field to be validated.
• Handles type interface by determining it's underlying type prior to validation.
• Handles custom field types such as sql driver Valuer see Valuer
• Alias validation tags, which allows for mapping of several validations to a single tag for easier defining of validations on structs
• Extraction of custom defined Field Name e.g. can specify to extract the JSON name while validating and have it available in the resulting FieldError
• Customizable i18n aware error messages.
• Default validator for the gin web framework; upgrading from v8 to v9 in gin see here

Installation

Use go get.

go get gopkg.in/go-playground/validator.v9

Then import the validator package into your own code.

import "gopkg.in/go-playground/validator.v9"

Error Return Value

Validation functions return type error

They return type error to avoid the issue discussed in the following, where err is always != nil:

• http://stackoverflow.com/a/29138676/3158232
• https://github.com/go-playground/validator/issues/134

Validator only InvalidValidationError for bad validation input, nil or ValidationErrors as type error; so, in your code all you need to do is check if the error returned is not nil, and if it's not check if error is InvalidValidationError ( if necessary, most of the time it isn't ) type cast it to type ValidationErrors like so:

err := validate.Struct(mystruct)
validationErrors := err.(validator.ValidationErrors)

Usage and documentation

Please see http://godoc.org/gopkg.in/go-playground/validator.v9 for detailed usage docs.

Examples:

• Simple
• Custom Field Types
• Struct Level
• Translations & Custom Errors
• Gin upgrade and/or override validator
• wash - an example application putting it all together

Benchmarks

Run on MacBook Pro (Retina, 15-inch, Late 2013) 2.6 GHz Intel Core i7 16 GB 1600 MHz DDR3 using Go version go1.7.1 darwin/amd64

BenchmarkFieldSuccess-8                                       	20000000	       106 ns/op
BenchmarkFieldSuccessParallel-8                               	50000000	        33.7 ns/op
BenchmarkFieldFailure-8                                       	 5000000	       346 ns/op
BenchmarkFieldFailureParallel-8                               	20000000	       115 ns/op
BenchmarkFieldDiveSuccess-8                                   	 2000000	       739 ns/op
BenchmarkFieldDiveSuccessParallel-8                           	10000000	       246 ns/op
BenchmarkFieldDiveFailure-8                                   	 1000000	      1043 ns/op
BenchmarkFieldDiveFailureParallel-8                           	 5000000	       381 ns/op
BenchmarkFieldCustomTypeSuccess-8                             	 5000000	       270 ns/op
BenchmarkFieldCustomTypeSuccessParallel-8                     	20000000	        92.5 ns/op
BenchmarkFieldCustomTypeFailure-8                             	 5000000	       331 ns/op
BenchmarkFieldCustomTypeFailureParallel-8                     	20000000	       132 ns/op
BenchmarkFieldOrTagSuccess-8                                  	 2000000	       874 ns/op
BenchmarkFieldOrTagSuccessParallel-8                          	 5000000	       368 ns/op
BenchmarkFieldOrTagFailure-8                                  	 3000000	       566 ns/op
BenchmarkFieldOrTagFailureParallel-8                          	 5000000	       427 ns/op
BenchmarkStructLevelValidationSuccess-8                       	 5000000	       335 ns/op
BenchmarkStructLevelValidationSuccessParallel-8               	20000000	       124 ns/op
BenchmarkStructLevelValidationFailure-8                       	 2000000	       630 ns/op
BenchmarkStructLevelValidationFailureParallel-8               	10000000	       298 ns/op
BenchmarkStructSimpleCustomTypeSuccess-8                      	 3000000	       535 ns/op
BenchmarkStructSimpleCustomTypeSuccessParallel-8              	10000000	       170 ns/op
BenchmarkStructSimpleCustomTypeFailure-8                      	 2000000	       821 ns/op
BenchmarkStructSimpleCustomTypeFailureParallel-8              	 5000000	       379 ns/op
BenchmarkStructFilteredSuccess-8                              	 2000000	       769 ns/op
BenchmarkStructFilteredSuccessParallel-8                      	 5000000	       328 ns/op
BenchmarkStructFilteredFailure-8                              	 2000000	       594 ns/op
BenchmarkStructFilteredFailureParallel-8                      	10000000	       244 ns/op
BenchmarkStructPartialSuccess-8                               	 2000000	       682 ns/op
BenchmarkStructPartialSuccessParallel-8                       	 5000000	       291 ns/op
BenchmarkStructPartialFailure-8                               	 1000000	      1034 ns/op
BenchmarkStructPartialFailureParallel-8                       	 5000000	       392 ns/op
BenchmarkStructExceptSuccess-8                                	 1000000	      1014 ns/op
BenchmarkStructExceptSuccessParallel-8                        	10000000	       257 ns/op
BenchmarkStructExceptFailure-8                                	 2000000	       875 ns/op
BenchmarkStructExceptFailureParallel-8                        	 5000000	       405 ns/op
BenchmarkStructSimpleCrossFieldSuccess-8                      	 3000000	       545 ns/op
BenchmarkStructSimpleCrossFieldSuccessParallel-8              	10000000	       177 ns/op
BenchmarkStructSimpleCrossFieldFailure-8                      	 2000000	       787 ns/op
BenchmarkStructSimpleCrossFieldFailureParallel-8              	 5000000	       341 ns/op
BenchmarkStructSimpleCrossStructCrossFieldSuccess-8           	 2000000	       795 ns/op
BenchmarkStructSimpleCrossStructCrossFieldSuccessParallel-8   	10000000	       267 ns/op
BenchmarkStructSimpleCrossStructCrossFieldFailure-8           	 1000000	      1119 ns/op
BenchmarkStructSimpleCrossStructCrossFieldFailureParallel-8   	 3000000	       437 ns/op
BenchmarkStructSimpleSuccess-8                                	 5000000	       377 ns/op
BenchmarkStructSimpleSuccessParallel-8                        	20000000	       110 ns/op
BenchmarkStructSimpleFailure-8                                	 2000000	       785 ns/op
BenchmarkStructSimpleFailureParallel-8                        	 5000000	       302 ns/op
BenchmarkStructComplexSuccess-8                               	 1000000	      2159 ns/op
BenchmarkStructComplexSuccessParallel-8                       	 2000000	       723 ns/op
BenchmarkStructComplexFailure-8                               	  300000	      5237 ns/op
BenchmarkStructComplexFailureParallel-8                       	 1000000	      2378 ns/op

Complimentary Software

Here is a list of software that compliments using this library either pre or post validation.

• form - Decodes url.Values into Go value(s) and Encodes Go value(s) into url.Values. Dual Array and Full map support.
• Conform - Trims, sanitizes & scrubs data based on struct tags.

How to Contribute

Make a pull request...

License

Distributed under MIT License, please see license file in code for more details.