w-json-stream
v1.0.21
Published
A tool for JSON parse and stringify by stream and web worker.
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Maintainers
semisphereReadme
w-json-stream
A tool for JSON parse and stringify by stream and web worker.
Documentation
To view documentation or get support, visit docs.
Installation
Using npm(ES6 module):
Note: w-json-stream is mainly dependent on
from2andjsonparse.
npm i w-json-streamExample for samll data:
Link: [dev source code]
async function testSmall() {
let obj = {
a: 123,
b: 145.67,
c: 'test中文1',
d: true,
f: [11, 'xyz', false, [166, 197, 215]],
g: {
ga: 223,
gb: 245.67,
gc: 'test中文2',
gd: [66, 97, 115],
},
}
let arr = [
{
a: 123,
b: 145.67,
c: 'test中文1',
d: true,
},
{
f: [11, 'xyz', false, [166, 197, 215]],
g: {
ga: 223,
gb: 245.67,
gc: 'test中文2',
gd: [66, 97, 115],
},
},
]
let jobj = await json.stringify(obj)
console.log(jobj)
// => {"a":123,"b":145.67,"c":"test中文1","d":true,"f":[11,"xyz",false,[166,197,215]],"g":{"ga":223,"gb":245.67,"gc":"test中文2","gd":[66,97,115]}}
let jarr = await json.stringify(arr)
console.log(jarr)
// => [{"a":123,"b":145.67,"c":"test中文1","d":true},{"f":[11,"xyz",false,[166,197,215]],"g":{"ga":223,"gb":245.67,"gc":"test中文2","gd":[66,97,115]}}]
let robj = await json.parse(jobj)
console.log(robj)
// => {
// a: 123,
// b: 145.67,
// c: 'test中文1',
// d: true,
// f: [ 11, 'xyz', false, [ 166, 197, 215 ] ],
// g: { ga: 223, gb: 245.67, gc: 'test中文2', gd: [ 66, 97, 115 ] }
// }
let rarr = await json.parse(jarr)
console.log(rarr)
// => [
// { a: 123, b: 145.67, c: 'test中文1', d: true },
// {
// f: [ 11, 'xyz', false, [Array] ],
// g: { ga: 223, gb: 245.67, gc: 'test中文2', gd: [Array] }
// }
// ]
}
testSmall()
.catch((err) => {
console.log(err)
})
Example for large data:
Link: [dev source code]
async function testLarge() {
let n = 700 //7000, 9000
let lgRows = []
for (let i = 1; i <= 1000; i++) {
lgRows.push([i, 23.4, '567', 'abc', true, false, [], {}, [8, 9.01], { a: 12.34, b: 'xyz', i }])
}
let lgArr = []
for (let i = 1; i <= n; i++) {
lgArr.push({
key: 'k' + i,
value: {
a: 123,
b: 145.67,
c: 'test中文1',
d: true,
f: [11, 'xyz', false, [166, 197, 215]],
g: {
ga: 223,
gb: 245.67,
gc: 'test中文2',
gd: [66, 97, 115],
ge: JSON.parse(JSON.stringify(lgRows)),
},
}
})
}
if (true) {
try {
let res = JSON.stringify(lgArr)
console.log('JSON.stringify(lgArr)', res.length, res.substr(0, 200) + '...')
}
catch (err) {
console.log('JSON.stringify(lgArr) catch', err)
// n=7000 => catch RangeError: Invalid string length => Out Of Memory
// n=9000 => FATAL ERROR: MarkCompactCollector: young object promotion failed Allocation failed - JavaScript heap out of memory
}
}
if (true) {
await json.stringify(lgArr)
.then((res) => {
console.log('json.stringify(lgArr) then', res.length, res.substr(0, 200) + '...')
})
.catch((err) => {
console.log('json.stringify(lgArr) catch', err)
// n=7000 => FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed - JavaScript heap out of memory
})
}
}
testLarge()
.catch((err) => {
console.log(err)
})
Example for stream:
Link: [dev source code]
async function testStream() {
async function testStringify() {
return new Promise((resolve, reject) => {
//fp
let fp = './temp-stringify.json'
//arr
let n = 4000 //4000000
let arr = []
for (let i = 1; i <= n; i++) {
arr.push({
key: 'k' + i,
value: {
a: 123,
b: 145.67,
c: 'test中文1',
d: true,
f: [11, 'xyz', false, [166, 197, 215]],
g: {
ga: 223,
gb: 245.67,
gc: 'test中文2',
gd: [66, 97, 115],
},
}
})
}
//createStringifyStream
let stringifyStream = json.createStringifyStream(arr)
//createWriteStream
let writerStream = fs.createWriteStream(fp)
// //pipe
// stringifyStream.pipe(writerStream)
//stringifyStream onData
stringifyStream.on('data', function(chunk) {
writerStream.write(chunk, 'UTF8')
})
//stringifyStream onEnd
stringifyStream.on('end', function() {
writerStream.end()
})
//writerStream onFinish
writerStream.on('finish', function() {
console.log('writerStream finish')
let res = fs.readFileSync(fp, 'utf8')
fs.unlinkSync(fp)
console.log('res.length', res.length)
console.log('res', res.substr(0, 200) + '...')
resolve()
})
//writerStream onError
writerStream.on('error', function(err) {
console.log('writerStream error', err)
})
})
}
async function testStringifys() {
await testStringify()
// writerStream finish
// res.length 646894
// res [{"key":"k1","value":{"a":123,"b":145.67,"c":"test中文1","d":true,"f":[11,"xyz",false,[166,197,215]],"g":{"ga":223,"gb":245.67,"gc":"test中文2","gd":[66,97,115]}}},{"key":"k2","value":{"a":123,"b":145.67,...
}
console.log('testStringify...')
await testStringifys()
.catch((err) => {
console.log(err)
})
async function testParse(pre, filter) {
return new Promise((resolve, reject) => {
//fp
let fp = './temp-write.json'
//arr
let arr = [
{
key: 'k1',
value: {
a: 123,
b: 145.67,
c: 'test中文1',
d: true,
f: [11, 'xyz', false, [166, 197, 215]],
g: {
ga: 223,
gb: 245.67,
gc: 'test中文2',
gd: [66, 97, 115],
},
},
},
{
child: [
{ name: 'child:abc', labels: ['child:label-abc'] },
{ name: 'child:def', labels: ['child:label-def'] },
true,
false,
2020,
{
name: 'child:xyz',
query: {
labels: ['child:query:label-xyz']
}
},
],
},
{ name: 'abc', labels: ['label-abc'] },
{ name: 'def', labels: ['label-def'] },
true,
false,
-1,
{
name: 'xyz',
query: {
labels: ['query:label-xyz']
}
},
]
//jarr
let jarr = JSON.stringify(arr)
//writeFileSync
fs.writeFileSync(fp, jarr, 'utf8')
//createReadStream
let readerStream = fs.createReadStream(fp)
//createParseStream
let parseStream = json.createParseStream(filter)
//onData
let res = []
parseStream.on('data', function(chunk) {
console.log(pre, 'parseStream data chunk=', chunk)
res.push(chunk)
})
//onEnd
parseStream.on('end', function() {
console.log(pre, 'parseStream end res', res)
fs.unlinkSync(fp)
resolve()
})
//onError
parseStream.on('error', function(err) {
console.log(pre, 'parseStream error', err)
})
//pipe
readerStream.pipe(parseStream)
})
}
async function testParses() {
let filter
filter = '' //default
console.log('test0', filter)
await testParse('test0', filter)
// test0
// test0 parseStream data chunk= {
// value: {
// key: 'k1',
// value: {
// a: 123,
// b: 145.67,
// c: 'test中文1',
// d: true,
// f: [Array],
// g: [Object]
// }
// },
// key: 0
// }
// test0 parseStream data chunk= {
// value: { child: [ [Object], [Object], true, false, 2020, [Object] ] },
// key: 1
// }
// test0 parseStream data chunk= { value: { name: 'abc', labels: [ 'label-abc' ] }, key: 2 }
// test0 parseStream data chunk= { value: { name: 'def', labels: [ 'label-def' ] }, key: 3 }
// test0 parseStream data chunk= { value: true, key: 4 }
// test0 parseStream data chunk= { value: false, key: 5 }
// test0 parseStream data chunk= { value: -1, key: 6 }
// test0 parseStream data chunk= { value: { name: 'xyz', query: { labels: [Array] } }, key: 7 }
// test0 parseStream end res [
// { value: { key: 'k1', value: [Object] }, key: 0 },
// { value: { child: [Array] }, key: 1 },
// { value: { name: 'abc', labels: [Array] }, key: 2 },
// { value: { name: 'def', labels: [Array] }, key: 3 },
// { value: true, key: 4 },
// { value: false, key: 5 },
// { value: -1, key: 6 },
// { value: { name: 'xyz', query: [Object] }, key: 7 }
// ]
filter = '*.labels' //無emit, 只能監聽onData個別處理
console.log('test1', filter)
await testParse('test1', filter)
// test1 *.labels
// test1 parseStream data chunk= [ 'label-abc' ]
// test1 parseStream data chunk= [ 'label-def' ]
// test1 parseStream end res [ [ 'label-abc' ], [ 'label-def' ] ]
filter = [true, 'labels', { emitPath: true }]
console.log('test2', filter, 'true=*, 開啟emitPath才能塞回物件取得過濾後結果')
await testParse('test2', filter)
// test2 [ true, 'labels', { emitPath: true } ] true=*, 開啟emitPath才能塞回物件取得過濾後結果
// test2 parseStream data chunk= { value: 'label-abc', path: [ 2, 'labels', 0 ] }
// test2 parseStream data chunk= { value: 'label-def', path: [ 3, 'labels', 0 ] }
// test2 parseStream end res [
// { value: 'label-abc', path: [ 2, 'labels', 0 ] },
// { value: 'label-def', path: [ 3, 'labels', 0 ] }
// ]
filter = [{ recurse: true }, 'labels', { emitPath: true }]
console.log('test3', filter, '開啟recurse代表為任意子節點, 開啟emitPath才能塞回物件取得過濾後結果')
await testParse('test3', filter)
// test3 [ { recurse: true }, 'labels', { emitPath: true } ] 開啟recurse代表為任意子節點, 開啟emitPath才能塞回物件取得過濾後結果
// test3 parseStream data chunk= { value: 'child:label-abc', path: [ 1, 'child', 0, 'labels', 0 ] }
// test3 parseStream data chunk= { value: 'child:label-def', path: [ 1, 'child', 1, 'labels', 0 ] }
// test3 parseStream data chunk= {
// value: 'child:query:label-xyz',
// path: [ 1, 'child', 5, 'query', 'labels', 0 ]
// }
// test3 parseStream data chunk= { value: 'label-abc', path: [ 2, 'labels', 0 ] }
// test3 parseStream data chunk= { value: 'label-def', path: [ 3, 'labels', 0 ] }
// test3 parseStream data chunk= { value: 'query:label-xyz', path: [ 7, 'query', 'labels', 0 ] }
// test3 parseStream end res [
// { value: 'child:label-abc', path: [ 1, 'child', 0, 'labels', 0 ] },
// { value: 'child:label-def', path: [ 1, 'child', 1, 'labels', 0 ] },
// {
// value: 'child:query:label-xyz',
// path: [ 1, 'child', 5, 'query', 'labels', 0 ]
// },
// { value: 'label-abc', path: [ 2, 'labels', 0 ] },
// { value: 'label-def', path: [ 3, 'labels', 0 ] },
// { value: 'query:label-xyz', path: [ 7, 'query', 'labels', 0 ] }
// ]
}
console.log('testParse...')
await testParses()
.catch((err) => {
console.log(err)
})
}
testStream()
.catch((err) => {
console.log(err)
})
In a browser(UMD module):
Note: w-json-stream does not dependent on any package.
[Necessary] Add script for w-json-stream.
<!-- for basic -->
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/w-json-stream.umd.js"></script>
<!-- for web workers -->
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/w-json-stream.wk.umd.js"></script>
stringify and parse for small data: ex-small.html [source code]
stringifyByStream and parseByStream for small data: ex-small-stream.html [source code]
stringify and parse for large data: ex-large.html [source code]
createParseStream: ex-stream-createParseStream.html [source code] * ReadableStream does not support IE11.
createParseStream with filter: ex-stream-createParseStreamWithFilter.html [source code]
createStringifyStream: ex-stream-createStringifyStream.html [source code] * WritableStream does not support IE11 and Firefox.
stringify and parse for large data in web worker: ex-large-webworker.html [source code] * WebWorkers(from blob) does not support IE11.
console.log('WebWorkers(from blob) does not support IE11')
let json = window['w-json-stream']
console.log(json)
console.log('build data...')
let n = 700 //7000, 9000
let lgRows = []
for (let i = 1; i <= 1000; i++) {
lgRows.push([i, 23.4, '567', 'abc', true, false, [], {}, [8, 9.01], { a: 12.34, b: 'xyz', i }])
}
let carr = ''
let arr = []
for (let i = 1; i <= n; i++) {
arr.push({
key: 'k' + i,
value: {
a: 123,
b: 145.67,
c: 'test中文1',
d: true,
f: [11, 'xyz', false, [166, 197, 215]],
g: {
ga: 223,
gb: 245.67,
gc: 'test中文2',
gd: [66, 97, 115],
ge: JSON.parse(JSON.stringify(lgRows)),
},
}
})
}
console.log('build data finish')
let t=0
let timer=setInterval(function(){
console.log('t',t/10+'(s)')
t++
if(t>50){
clearInterval(timer)
}
},100)
let pmArr = json.stringify(arr)
.then(function(res){
console.log('json.stringify(arr) then',res)
carr = res
})
.catch(function(err){
console.log('json.stringify(arr) catch',err)
})
Promise.all([pmArr])
.then(function(){
json.parse(carr)
.then(function(r){
console.log('json.parse(carr) then',r)
})
.catch(function(err){
console.log('json.parse(carr) catch',err)
})
})
.catch(function(err){
console.log(err)
})