rudfoss · March 26, 2024 10:40 · Mar 26, 2024
diff --git a/convertDataToCsvRows.ts b/convertDataToCsvRows.ts
@@ -0,0 +1,67 @@
+const sanitizeCellValue = (value: unknown, cellSeparator: string): string => {
+	let valueString = String(value ?? "")
+	if (
+		valueString.includes(cellSeparator) ||
+		valueString.includes(" ") ||
+		valueString.includes('"') ||
+		valueString.includes("\n")
+	) {
+		valueString = valueString.replaceAll('"', '""')
+		valueString = `"${valueString}"`
+	}
+	return valueString
+}
+
+/**
+ * Given a data set will convert it to a csv string with a header and newline-separated rows.
+ * @param data The data to convert
+ * @param columns The name of each property to include. If not specified will infer properties based on the first row.
+ * @param cellSeparator The separator character to use between cells. Defaults to comma.
+ * @returns
+ */
+export const convertDataToCsvRows = <TRow extends object>(
+	data: TRow[],
+	columns?: Array<keyof TRow>,
+	cellSeparator: "," | ";" | "\t" | " " = ","
+) => {
+	const columnsInOrder = columns ?? (Object.keys(data[0] ?? {}) as Array<keyof TRow>)
+	const columnNames = columnsInOrder
+		.map((columnName) => sanitizeCellValue(columnName, cellSeparator))
+		.join(cellSeparator)
+
+	if (data.length === 0) {
+		return [columnNames].join("\n")
+	}
+
+	const rows = data.map((row) =>
+		columnsInOrder
+			.map((columnName) => sanitizeCellValue(row[columnName], cellSeparator))
+			.join(cellSeparator)
+	)
+
+	return [columnNames, ...rows].join("\n")
+}
+
+/**
+ * Creates a url for downloading the CSV data provided as a file.
+ * @param csvData
+ * @returns A function that will trigger the download when called.
+ */
+export const makeDownloadableCsv = (
+	csvData: string,
+	filename: string,
+	type = "text/csv;charset=utf-8"
+) => {
+	const blob = new Blob([csvData], { type })
+	const url = URL.createObjectURL(blob)
+	const downloadLink = document.createElement("a")
+	downloadLink.href = url
+	downloadLink.download = filename
+	downloadLink.style.visibility = "hidden"
+
+	return () => {
+		document.body.append(downloadLink)
+		downloadLink.click()
+		downloadLink.remove()
+	}
+}