DMleadgen
46d973904b
Next.js website for Rocky Mountain Vending company featuring: - Product catalog with Stripe integration - Service areas and parts pages - Admin dashboard with Clerk authentication - SEO optimized pages with JSON-LD structured data Co-authored-by: Cursor <cursoragent@cursor.com>
30 lines
1.9 KiB
Text
30 lines
1.9 KiB
Text
import { Crc32 } from "@aws-crypto/crc32";
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const PRELUDE_MEMBER_LENGTH = 4;
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const PRELUDE_LENGTH = PRELUDE_MEMBER_LENGTH * 2;
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const CHECKSUM_LENGTH = 4;
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const MINIMUM_MESSAGE_LENGTH = PRELUDE_LENGTH + CHECKSUM_LENGTH * 2;
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export function splitMessage({ byteLength, byteOffset, buffer }) {
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if (byteLength < MINIMUM_MESSAGE_LENGTH) {
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throw new Error("Provided message too short to accommodate event stream message overhead");
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}
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const view = new DataView(buffer, byteOffset, byteLength);
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const messageLength = view.getUint32(0, false);
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if (byteLength !== messageLength) {
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throw new Error("Reported message length does not match received message length");
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}
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const headerLength = view.getUint32(PRELUDE_MEMBER_LENGTH, false);
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const expectedPreludeChecksum = view.getUint32(PRELUDE_LENGTH, false);
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const expectedMessageChecksum = view.getUint32(byteLength - CHECKSUM_LENGTH, false);
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const checksummer = new Crc32().update(new Uint8Array(buffer, byteOffset, PRELUDE_LENGTH));
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if (expectedPreludeChecksum !== checksummer.digest()) {
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throw new Error(`The prelude checksum specified in the message (${expectedPreludeChecksum}) does not match the calculated CRC32 checksum (${checksummer.digest()})`);
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}
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checksummer.update(new Uint8Array(buffer, byteOffset + PRELUDE_LENGTH, byteLength - (PRELUDE_LENGTH + CHECKSUM_LENGTH)));
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if (expectedMessageChecksum !== checksummer.digest()) {
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throw new Error(`The message checksum (${checksummer.digest()}) did not match the expected value of ${expectedMessageChecksum}`);
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}
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return {
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headers: new DataView(buffer, byteOffset + PRELUDE_LENGTH + CHECKSUM_LENGTH, headerLength),
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body: new Uint8Array(buffer, byteOffset + PRELUDE_LENGTH + CHECKSUM_LENGTH + headerLength, messageLength - headerLength - (PRELUDE_LENGTH + CHECKSUM_LENGTH + CHECKSUM_LENGTH)),
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};
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}
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