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JavaScript async generator/reader/transformer
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| const genline = async (i) => [Date.now(), i, "CRITICAL", "gui", ": asfd asdf asdf asdf asdf asdf asdf asdf asdf asdf asdf asdf asdf"].join(" ") | |
| const generate = amount => { | |
| let arr = []; | |
| for(let i = 0; i < amount; i++) { | |
| arr.push(genline(i)) | |
| } | |
| return arr | |
| } | |
| const transformer = { | |
| decoder: new TextDecoder(), | |
| lastString: '', | |
| transform: function(chunk, controller) { | |
| const string = `${this.lastString}${this.decoder.decode(chunk)}`; | |
| const lines = string.split(/\r\n|[\r\n]/g); | |
| this.lastString = lines.pop() || ''; | |
| for (const line of lines) { | |
| controller.enqueue(line) | |
| } | |
| }, | |
| flush: function(controller) { | |
| if(this.lastString) controller.enqueue(this.lastString) | |
| } | |
| } | |
| const url = async amount => | |
| URL.createObjectURL( | |
| new Blob([(await Promise.all(generate(amount))).join("\n")], {type: 'text/plain'} | |
| ) | |
| ) | |
| const getme = async (amount, fn) => | |
| fetch(await url(amount)) | |
| .then(rs => rs.body) | |
| .then(rs => rs.pipeThrough(new TransformStream(transformer))) | |
| .then(rs => rs.getReader()) | |
| .then(async reader => { | |
| while(true){ | |
| const {done, value} = await reader.read(); | |
| if(done) break; | |
| fn(value) | |
| } | |
| } | |
| ) | |
| getme(100000, res => document.body.innerText = res) |
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