This library is compatible with Go 1.15+
Please refer to CHANGELOG.md if you encounter breaking changes.
The goal of this project is to use dynamic data types without defining native GO structs with minimum memory footprint. Alternative would be just using map, but that is way too inefficient. Having dynamic type safe objects enables building generic solution for REST/Micro Service/ETL etc. To build dynamic solution dynamic object should be easily transferable into common format like JSON, AVRO, ProtoBuf, etc....
Gtly complex data type use slice based storage with Proto reference to reduce memory footprint and to avoid reflection. An proto instance is shared across all Object and Collection of the same type. Proto control mapping between field and field position withing object, or slice item. What's more proto field define field meta data like DateLayout, OutputName controlled by proto CaseFormat dynamically.
package mypacakge
import (
"fmt"
"github.com/viant/gtly"
"github.com/viant/gtly/codec/json"
"log"
"time"
)
func NewObject_Usage() {
fooProvider := gtly.NewProvider("foo", //create foo type
gtly.NewField("id", gtly.FieldTypeInt),
gtly.NewField("firsName", gtly.FieldTypeString),
gtly.NewField("description", gtly.FieldTypeString, gtly.OmitEmptyOpt(true)),
gtly.NewField("updated", gtly.FieldTypeTime, gtly.DateLayoutOpt("2006-01-02T15:04:05Z07:00")),
gtly.NewField("numbers", gtly.FieldTypeArray, gtly.ComponentTypeOpt(gtly.FieldTypeInt)),
)
//create an instance of foo type
foo1 := fooProvider.NewObject()
foo1.SetInt("id", 1)
foo1.SetString("firsName", "Adam")
foo1.SetTime("updated", time.Now())
foo1.SetValue("numbers", []int{1, 2, 3})
JSON, err := json.Marshal(foo1)
if err != nil {
log.Fatal(err)
}
fmt.Printf("%s\n", JSON)
//Prints: {"id":1,"firsName":"Adam","updated":"2020-09-25T20:43:40-07:00","numbers":[1,2,3]}
//change foo type output to upper underscore
fooProvider.OutputCaseFormat(gtly.CaseLowerCamel, gtly.CaseUpperUnderscore)
JSON, _ = json.Marshal(foo1)
fmt.Printf("%s\n", JSON)
//Prints: {"ID":1,"FIRS_NAME":"Adam","UPDATED":"2020-09-25T20:43:40-07:00","NUMBERS":[1,2,3]}
//change foo type output to lower underscore
fooProvider.OutputCaseFormat(gtly.CaseLowerCamel, gtly.CaseLowerUnderscore)
foo1.SetBool("active", true) //add dynamically new field
foo1.SetString("description", "some description") // set value for existing field
JSON, _ = json.Marshal(foo1)
fmt.Printf("%s\n", JSON)
//Prints: {"id":1,"firs_name":"Adam","description":"some description","updated":"2020-09-25T20:43:40-07:00","numbers":[1,2,3],"active":true}
//create another instance of foo type
foo2 := fooProvider.NewObject()
JSON, _ = json.Marshal(foo2)
fmt.Printf("%s\n", JSON)
}package mypacakge
import (
"fmt"
"github.com/viant/gtly"
"github.com/viant/gtly/codec/json"
"log"
"time"
)
func NewArray_Usage() {
fooProvider := gtly.NewProvider("foo",
gtly.NewField("id", gtly.FieldTypeInt),
gtly.NewField("firsName", gtly.FieldTypeString),
gtly.NewField("income", gtly.FieldTypeFloat),
gtly.NewField("description", gtly.FieldTypeString, gtly.OmitEmptyOpt(true)),
gtly.NewField("updated", gtly.FieldTypeTime, gtly.DateLayoutOpt(time.RFC3339)),
gtly.NewField("numbers", gtly.FieldTypeArray, gtly.ComponentTypeOpt(gtly.FieldTypeInt)),
)
fooArray1 := fooProvider.NewArray()
for i:=0;i<10;i++ {
foo1 := fooProvider.NewObject()
foo1.SetInt("id", 1)
foo1.SetFloat("income", 64000.0*float64(1+(10/(i+1))))
foo1.SetString("firsName", "Adam")
fooArray1.AddObject(foo1)
}
now := time.Now()
fooArray1.Add(map[string]interface{}{
"id": 100,
"firsName": "Tom",
"updated": now,
})
totalIncome := 0.0
incomeField := fooProvider.Field("income")
//Iterating collection
err := fooArray1.Objects(func(object *gtly.Object) (bool, error) {
fmt.Printf("id: %v\n", object.Int("id"))
fmt.Printf("name: %v\n", object.String("name"))
totalIncome += object.FloatAt(incomeField.Index)
return true, nil
})
fmt.Printf("income total: %v\n", totalIncome)
if err != nil {
log.Fatal(err)
}
JSON, err := json.Marshal(fooArray1)
if err != nil {
log.Fatal(err)
}
fmt.Printf("%s", JSON)
}package mypacakge
import (
"fmt"
"github.com/viant/gtly"
"github.com/viant/gtly/codec/json"
"log"
"time"
)
func NewMap_Usage() {
fooProvider := gtly.NewProvider("foo",
gtly.NewField("id", gtly.FieldTypeInt),
gtly.NewField("firsName", gtly.FieldTypeString),
gtly.NewField("description", gtly.FieldTypeString, gtly.OmitEmptyOpt(true)),
gtly.NewField("updated", gtly.FieldTypeTime, gtly.DateLayoutOpt(time.RFC3339)),
gtly.NewField("numbers", gtly.FieldTypeArray, gtly.ComponentTypeOpt(gtly.FieldTypeInt)),
)
//Creates a map keyed by id field
aMap := fooProvider.NewMap(gtly.NewIndex([]string{"id"}))
for i := 0; i < 10; i++ {
foo := fooProvider.NewObject()
foo.SetInt("id", i)
foo.SetString("firsName", fmt.Sprintf("Name %v", i))
aMap.AddObject(foo)
}
//Accessing map
foo1 := aMap.Object("1")
JSON, err := json.Marshal(foo1)
if err != nil {
log.Fatal(err)
}
fmt.Printf("%s\n", JSON)
//Prints {"id":1,"firsName":"Name 1","updated":null,"numbers":null}
//Iterating map
aMap.Pairs(func(key string, item *gtly.Object) (bool, error) {
fmt.Printf("id: %v\n", item.Int("id"))
fmt.Printf("name: %v\n", item.String("name"))
return true, nil
})
JSON, err = json.Marshal(aMap)
if err != nil {
log.Fatal(err)
}
fmt.Printf("%s\n", JSON)
//[{"id":1,"firsName":"Name 1","updated":null,"numbers":null},{"id":3,"firsName":"Name 3","updated":null,"numbers":null},{"id":4,"firsName":"Name 4","updated":null,"numbers":null},{"id":6,"firsName":"Name 6","updated":null,"numbers":null},{"id":8,"firsName":"Name 8","updated":null,"numbers":null},{"id":9,"firsName":"Name 9","updated":null,"numbers":null},{"id":0,"firsName":"Name 0","updated":null,"numbers":null},{"id":2,"firsName":"Name 2","updated":null,"numbers":null},{"id":5,"firsName":"Name 5","updated":null,"numbers":null},{"id":7,"firsName":"Name 7","updated":null,"numbers":null}]
}func NewMultiMap_Usage() {
fooProvider := gtly.NewProvider("foo",
gtly.NewField("id", gtly.FieldTypeInt),
gtly.NewField("firsName", gtly.FieldTypeString),
gtly.NewField("city", gtly.FieldTypeString, gtly.OmitEmptyOpt(true)),
gtly.NewField("updated", gtly.FieldTypeTime, gtly.DateLayoutOpt(time.RFC3339)),
gtly.NewField("numbers", gtly.FieldTypeArray, gtly.ComponentTypeOpt(gtly.FieldTypeInt)),
)
//Creates a multi map keyed by id field
aMap := fooProvider.NewMultimap(gtly.NewIndex([]string{"city"}))
for i := 0; i < 10; i++ {
foo := fooProvider.NewObject()
foo.SetInt("id", i)
foo.SetString("firsName", fmt.Sprintf("Name %v", i))
if i % 2 ==0 {
foo.SetString("city", "Cracow")
} else {
foo.SetString("city", "Warsaw")
}
aMap.AddObject(foo)
}
//Accessing map
fooInWarsawSlice := aMap.Slice("Warsaw")
JSON, err := json.Marshal(fooInWarsawSlice)
if err != nil {
log.Fatal(err)
}
fmt.Printf("%s\n", JSON)
//Prints [{"id":1,"firsName":"Name 1","city":"Warsaw","updated":null,"numbers":null},{"id":3,"firsName":"Name 3","city":"Warsaw","updated":null,"numbers":null},{"id":5,"firsName":"Name 5","city":"Warsaw","updated":null,"numbers":null},{"id":7,"firsName":"Name 7","city":"Warsaw","updated":null,"numbers":null},{"id":9,"firsName":"Name 9","city":"Warsaw","updated":null,"numbers":null}]
//Iterating multi map
err = aMap.Slices(func(key string, value *gtly.Array) (bool, error) {
fmt.Printf("%v -> %v\n", key, value.Size())
return true, nil
})
if err != nil {
log.Fatal(err)
}
JSON, err = json.Marshal(aMap)
if err != nil {
log.Fatal(err)
}
fmt.Printf("%s\n", JSON)
//[{"id":0,"firsName":"Name 0","city":"Cracow","updated":null,"numbers":null},{"id":2,"firsName":"Name 2","city":"Cracow","updated":null,"numbers":null},{"id":4,"firsName":"Name 4","city":"Cracow","updated":null,"numbers":null},{"id":6,"firsName":"Name 6","city":"Cracow","updated":null,"numbers":null},{"id":8,"firsName":"Name 8","city":"Cracow","updated":null,"numbers":null},{"id":1,"firsName":"Name 1","city":"Warsaw","updated":null,"numbers":null},{"id":3,"firsName":"Name 3","city":"Warsaw","updated":null,"numbers":null},{"id":5,"firsName":"Name 5","city":"Warsaw","updated":null,"numbers":null},{"id":7,"firsName":"Name 7","city":"Warsaw","updated":null,"numbers":null},{"id":9,"firsName":"Name 9","city":"Warsaw","updated":null,"numbers":null}]
}Gtly is an open source project and contributors are welcome!
See TODO list
The source code is made available under the terms of the Apache License, Version 2, as stated in the file LICENSE.
Individual files may be made available under their own specific license, all compatible with Apache License, Version 2. Please see individual files for details.
Library Author: Adrian Witas