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This is a code generation tool forQUICK struct content compare or hash computation.

中文介绍

• Quick compare nested struct without reflection (10~20 times faster)

  BenchmarkCompare/benchmark_reflect-810000020074ns/op//reflect.DeepEqualBenchmarkCompare/benchmark_hsp-85000002322ns/opBenchmarkCompare/benchmark_hsp_1_cached-810000001101ns/opBenchmarkCompare/benchmark_hsp_both_cached-810000000011.2ns/op

  bench cases seehere

• Quick calculation of struct hash or signature without reflection. used inCovenantSQL for block hash.

Basically it will generate anMarshalHash method which follow theMessagePack Spec but :

1. Without the struct key.
2. Stable output of map.
3. Can be used to compare different type with same hsp tag.

That is the following 2 structs with different member name

For more: seetest cases

//go:generate hsptypePerson1struct {NamestringAgeintAddressstringMapmap[string]intunexportedbool// this field is ignoredUnexportedstring`hsp:"-"`// this field is ignored}typePerson2struct {NamestringAddressstringAgeintMap222map[string]int`hspack:"Map"`unexportedbool// this field is ignoredUnexportedstring`hsp:"-"`// this field is ignored}

But with the same name and content of exported member,MarshalHash will produce the same bytes array:

package personimport ("bytes""testing")funcTestMarshalHashAccountStable3(t*testing.T) {p1:=Person1{Name:"Auxten",Address:"@CovenantSQL.io",Age:70,Map:map[string]int{"ss":2,"s":1,"sss":3},unexported:false,}p2:=Person2{Name:"Auxten",Address:"@CovenantSQL.io",Age:70,Map222:map[string]int{"ss":2,"s":1,"sss":3},unexported:true,}bts1,err:=p1.MarshalHash()iferr!=nil {t.Fatal(err)}bts2,err:=p2.MarshalHash()iferr!=nil {t.Fatal(err)}if!bytes.Equal(bts1,bts2) {t.Fatal("hash not stable")}}

the order of struct member is sorted by struct tag (if not, use name)

You can read more about MessagePackin the wiki, or atmsgpack.org.

• Use Go as your schema language
• Performance

• MessagePack: member name is unnecessary, different implementation may add some fields which made result undetermined. And also golang's map...
• Prorobuf: struct must defined in proto language, and other limitations discussedhere

1. Quick Install

go get -u github.com/CovenantSQL/HashStablePack/hsp

2. Add tag for sourceIn a source file, include the following directive:

//go:generate hsp

3. Run go generate

go generate ./...

Thehsp command will generate serialization methods for all exported type declarations in the file.

By default, the code generator will only generateMarshalHash andMsgsize method

func (z*Test)MarshalHash() (o []byte,errerror)func (z*Test)Msgsize() (sint)

• Extremely fast generated code
• Test and benchmark generation
• Support for complex type declarations
• Native support for Go'stime.Time,complex64, andcomplex128 types
• Support for arbitrary type system extensions
• File-based dependency model means fast codegen regardless of source tree size.

This lib is inspired byhttps://github.com/tinylib/msgpMost Code is diverted fromhttps://github.com/tinylib/msgp, but It's an total different lib for usage. So I created a new project instead of forking it.