75 lines
1.9 KiB
TypeScript
75 lines
1.9 KiB
TypeScript
const error = (code: string) => {
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// TODO: return proper errors and code here
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self.postMessage({
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cobaltFetchWorker: {
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error: code,
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}
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})
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};
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const fetchFile = async (url: string) => {
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try {
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const response = await fetch(url);
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if (!response.ok) {
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error("file response wasn't ok");
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return self.close();
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}
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const contentType = response.headers.get('Content-Type') || 'application/octet-stream';
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const contentLength = response.headers.get('Content-Length');
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const totalBytes = contentLength ? parseInt(contentLength, 10) : null;
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const reader = response.body?.getReader();
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if (!reader) {
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error("no reader");
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return self.close();
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}
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let receivedBytes = 0;
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const chunks = [];
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while (true) {
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const { done, value } = await reader.read();
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if (done) break;
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receivedBytes += value.length;
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chunks.push(value);
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if (totalBytes) {
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self.postMessage({
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cobaltFetchWorker: {
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progress: Math.round((receivedBytes / totalBytes) * 100),
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size: receivedBytes,
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}
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});
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}
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}
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if (receivedBytes === 0) {
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error("tunnel is broken");
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return self.close();
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}
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const file = new File(chunks, "file", { type: contentType });
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self.postMessage({
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cobaltFetchWorker: {
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file
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}
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});
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} catch (e) {
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console.log(e)
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error("error when downloading the file");
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return self.close();
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}
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}
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self.onmessage = async (event: MessageEvent) => {
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if (event.data.cobaltFetchWorker) {
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await fetchFile(event.data.cobaltFetchWorker.url);
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self.close();
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}
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}
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