Add script to remove old video descriptions

package.json

@@ -16,5 +16,8 @@
     "mixin-deep": "^2.0.1",
     "node-fetch": "^2.6.6",
     "pinski": "git+https://git.sr.ht/~cadence/nodejs-pinski#9653807f309aee34c8c63ce4e6ee760cccbfdf0d"
+  },
+  "devDependencies": {
+    "cli-progress": "^3.12.0"
   }
 }

scripts/min-video-data.js

@@ -0,0 +1,67 @@
+const fs = require("fs")
+const zlib = require("zlib")
+const progress = require("cli-progress")
+const {promisify} = require("util")
+const {pipeline} = require("stream")
+const pipe = promisify(pipeline)
+
+const db = require("../utils/db")
+
+const cutoff = new Date("2023-01-01").getTime() / 1000
+
+function* toRows(stmt) {
+	yield* stmt.raw().iterate(cutoff);
+}
+
+(async () => {
+	const countToMin = db.prepare("select count(*) from Videos where published < ?").pluck().get(cutoff)
+	const countTotal = db.prepare("select count(*) from Videos").pluck().get()
+	console.log("want to trim", countToMin, "out of", countTotal, "videos");
+
+	// ensure that we're not trimming the entire content
+	if (Math.abs(countTotal - countToMin) <= 10) {
+		throw new Error("failsafe: not trimming everything")
+	}
+
+	// export
+	const backupName = "video-descriptions-backup.jsonl.gz"
+	console.log(`exporting a backup to ${backupName}...`)
+	const contents = db.prepare("select videoId, descriptionHtml from Videos where published < ? order by author asc, published asc")
+
+	await new Promise((resolve, reject) => {
+		const rowsProgress = new progress.SingleBar({fps: 3}, progress.Presets.shades_classic)
+		const gzipProgress = new progress.SingleBar({fps: 3}, progress.Presets.shades_classic)
+
+		// write rows into gzip
+		const gzip = zlib.createGzip()
+		const dest = fs.createWriteStream(backupName)
+		gzip.pipe(dest)
+		rowsProgress.start(countToMin, 0)
+		for (const row of toRows(contents)) {
+			gzip.write(JSON.stringify(row))
+			rowsProgress.increment()
+		}
+		gzip.end()
+		rowsProgress.stop()
+
+		// track gzip progress
+		console.log("  compressing backup...")
+		const max = gzip._writableState.length
+		gzipProgress.start(max, 0)
+		const interval = setInterval(() => {
+			gzipProgress.update(max - gzip._writableState.length)
+		}, 100)
+		dest.on("finish", () => {
+			clearInterval(interval)
+			gzipProgress.stop()
+			resolve()
+		})
+	})
+
+	// do it!
+	console.log("removing descriptions...")
+	db.prepare("update videos set descriptionHtml = null where published < ?").run(cutoff)
+
+	console.log("reclaiming disk space from database...")
+	db.prepare("vacuum").run()
+})()