timtinkers.online
posts "question of the day" to a discord webhook
kv.atomic to mitigate accidental double posts
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main.ts
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main.ts
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// @ts-ignore Deno.cron is unstable, run with --unstable-cron flag
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Deno.cron("QOTD", Deno.env.get("CRON_STRING"), async () => {
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// Open KV and get last index
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// Fetch data
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const response = await fetch(endpoint);
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const { data } = await response.json();
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// Open KV and fetch last index
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// @ts-ignore Deno.openKv is unstable, run with --unstable-kv flag
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const kv = await Deno.openKv(
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// `https://api.deno.com/databases/${
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// Deno.env.get("DENO_KV_DATABASE_ID")
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// }/connect`,
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);
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const result = await kv.get<number>(["lastIndex"]);
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let index = result.value ?? 0;
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const current = await kv.get<number>(["lastIndex"]);
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const index = current.value ?? 0;
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const nextIndex = (index + 1) % data.length;
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const response = await fetch(endpoint);
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const { data } = await response.json();
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// Perform atomic operation to update index
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const result = await kv.atomic()
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.check(current) // Ensure the value hasn't changed
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.set(["lastIndex"], nextIndex)
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.commit();
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if (!result.ok) {
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console.log("Another instance already updated the index, skipping");
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return;
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}
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// Post to Discord webhook
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await sendDiscordNotification(data[index].question);
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console.log(`Cron: posted question of index ${index} to Discord.`);
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// Update last index in KV
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index = (index + 1) % data.length;
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await kv.set(["lastIndex"], index);
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});