propertyquery

README

Query nested properties & arrays using dot notation to get/set values.
Creates objects on pointers & extends array if value not present.

Import

go get -u github.com/markshapiro/property-query

import (
	query "github.com/markshapiro/property-query"
)

Usage

type MyStruct struct {
	Num     	int
	Text    	string
	Nested		NestedStruct
	Arr		    []string
	PtrToText	*string
	PtrToNested	*NestedStruct
}

type NestedStruct struct {
	Num            int
	Text           string
}

obj := MyStruct{
	Arr: []string{"a", "b", "c"},
}

// to set value
err = query.Set(&obj, "num", 123)
err = query.Set(&obj, "text", "abc")

// to get value as interface{}
value, _, err := query.Get(&obj, "text")

query.Set(&obj, "nested.num", 123)
query.Set(&obj, "nested.text", "abc")

// property name can start with capitalized leter
query.Set(&obj, "Nested.Text", "abc")
query.Set(&obj, "nested.Text", "abc")

Set(&obj, "arr[0]", "d")
query.Set(&obj, "arr[-2]", "e")	// will set 2nd last index
query.Set(&obj, "arr[10]", "f")	// will extend array to size 11

text := "some text"

query.Set(&obj, "PtrToText", &text)
query.Set(&obj, "PtrToText", text)	// will work too

// will initiate empty struct if PtrToNested initially points to nil
query.Set(&obj, "PtrToNested.num", 123)

filters := make(map[string]func(interface{}) bool)

filters["myFilter"] = func(val interface{}) bool {
	str := val.(string)
	return str == "a" || str == "c"
}

// will set new value to elements that match myFilter function
query.Set(&obj, "Arr[myFilter]", "new value", filters)

filters["myFilter2"] = func(val interface{}) bool {
	str := val.(string)
	return len(str) > 1
}

// will get array of interface{} of elements that match myFilter2
_, arr, err := query.Get(&obj, "Arr[myFilter2]", filters)

Documentation

Index

• Variables
• func Get(obj interface{}, path string, ...) (interface{}, []interface{}, error)
• func Set(obj interface{}, path string, value interface{}, ...) error

Variables

var (
	NoSuchField    = errors.New("no such field")
	ShouldUseSlice = errors.New("please provide slice type to extend array length")
)

Functions

func Get

func Get(obj interface{}, path string, arrayFilters ...map[string]func(interface{}) bool) (interface{}, []interface{}, error)

func Set

func Set(obj interface{}, path string, value interface{}, arrayFilters ...map[string]func(interface{}) bool) error