levelupjs

levelup bindings for gopherjs

This package implements the levelup interface, and at the same time wraps https://www.npmjs.com/package/levelup so you can use any of the supported leveldown backends.

how to use

package main

import (
	"github.com/fiatjaf/go-levelup"
	"github.com/fiatjaf/go-levelup-js"
	"github.com/fiatjaf/levelup/stringlevelup"
)

func main() {
	bdb := levelupjs.NewDatabase("my-beautiful-browser-database", "fruitdown")
	defer bdb.Erase()

	db := stringlevelup.StringDB(bdb)

	fmt.Println("setting key1 to x")
	db.Put("key1", "x")
	res, _ := db.Get("key1")
	fmt.Println("setting key2 to 2")
	fmt.Println("res at key2: ", res)
	db.Put("key2", "y")
	res, _ = db.Get("key2")
	fmt.Println("res at key2: ", res)
	fmt.Println("deleting key1")
	db.Del("key1")
	res, _ = db.Get("key1")
	fmt.Println("res at key1: ", res)

	fmt.Println("batch")
	db.Batch([]levelup.Operation{
		stringlevelup.Put("key2", "w"),
		stringlevelup.Put("key3", "z"),
		stringlevelup.Del("key1"),
		stringlevelup.Put("key1", "t"),
		stringlevelup.Put("key4", "m"),
		stringlevelup.Put("key5", "n"),
		stringlevelup.Del("key3"),
	})
	res, _ = db.Get("key1")
	fmt.Println("res at key1: ", res)
	res, _ = db.Get("key2")
	fmt.Println("res at key2: ", res)
	res, _ = db.Get("key3")
	fmt.Println("res at key3: ", res)

	fmt.Println("reading all")
	iter := db.ReadRange(nil)
	for ; iter.Valid(); iter.Next() {
		fmt.Println("row: ", iter.Key(), " ", iter.Value())
	}
	fmt.Println("iter error: ", iter.Error())
	iter.Release()

if you don't call stringlevelup.StringDB on the object returned by NewDatabase you still can use the same methods, only replacing all string arguments with []byte (returned values will also be bytes). I've just used the string approach here for readability, but it is slower.

levelupjs will try to require() both levelup and the name of the adapter you gave. If require is not available it will try to load these from the global namespace, so window.levelup and window[adapterName] must be set. If you're running this on a Node.js environment you should be fine with the above instructions, but if you're just using raw HTML you'll have to include these dependencies before, like:

How to use:

plain browser