sheetjs-pg-table-demo/sql-types.js

129 lines
4.5 KiB
JavaScript

const format = require("pg-format");
const XLSX = require('xlsx');
function deduceType(cells) {
if (!cells || cells.length === 0) return 'text';
const nonEmptyCells = cells.filter(cell => cell && cell.v != null);
if (nonEmptyCells.length === 0) return 'text';
// Check for dates by looking at both cell type and formatted value
const isDateCell = cell => cell?.t === 'd' || (cell?.t === 'n' && cell.w && /\d{4}-\d{2}-\d{2}|\d{1,2}\/\d{1,2}\/\d{4}|\d{2}-[A-Za-z]{3}-\d{4}|[A-Za-z]{3}-\d{2}|\d{1,2}-[A-Za-z]{3}/.test(cell.w));
if (nonEmptyCells.some(isDateCell)) { return 'date'; }
// Check for booleans
const allBooleans = nonEmptyCells.every(cell => cell.t === 'b');
if (allBooleans) { return 'boolean'; }
// Check for numbers
const allNumbers = nonEmptyCells.every(cell => cell.t === 'n' || (cell.t === 's' && !isNaN(cell.v.replace(/[,$\s%()]/g, ''))));
if (allNumbers) {
const numbers = nonEmptyCells.map(cell => {
if (cell.t === 'n') return cell.v;
return parseFloat(cell.v.replace(/[,$\s%()]/g, ''));
});
const needsPrecision = numbers.some(num => {
const str = num.toString();
return str.includes('e') ||
(str.includes('.') && str.split('.')[1].length > 6) ||
Math.abs(num) > 1e15;
});
return needsPrecision ? 'numeric' : 'double precision';
}
return 'text'; // default to string type
}
function parseValue(cell, type) {
if (!cell || cell.v == null) return null;
switch (type) {
case 'date':
if (cell.t === 'd') { return cell.v.toISOString().split('T')[0]; }
if (cell.t === 'n') {
const date = new Date((cell.v - 25569) * 86400 * 1000);
return date.toISOString().split('T')[0];
}
return null;
case 'numeric':
case 'double precision':
if (cell.t === 'n') return cell.v;
if (cell.t === 's') {
const cleaned = cell.v.replace(/[,$\s%()]/g, '');
if (!isNaN(cleaned)) return parseFloat(cleaned);
}
return null;
case 'boolean':
return cell.t === 'b' ? cell.v : null;
default:
return String(cell.v);
}
}
/* create table and load data given a worksheet and a PostgreSQL client */
async function sheet_to_pg_table(client, worksheet, tableName) {
if (!worksheet['!ref']) return;
const range = XLSX.utils.decode_range(worksheet['!ref']);
/* Extract headers from first row, clean names for PostgreSQL */
const headers = [];
for (let col = range.s.c; col <= range.e.c; col++) {
const cellAddress = XLSX.utils.encode_cell({ r: range.s.r, c: col });
const cell = worksheet[cellAddress];
const headerValue = cell ? String(cell.v).replace(/[^a-zA-Z0-9_]/g, '_') : `column_${col + 1}`;
headers.push(headerValue.toLowerCase());
}
/* Group cell values by column for type deduction */
const columnValues = headers.map(() => []);
for (let row = range.s.r + 1; row <= range.e.r; row++) {
for (let col = range.s.c; col <= range.e.c; col++) {
const cellAddress = XLSX.utils.encode_cell({ r: row, c: col });
const cell = worksheet[cellAddress];
columnValues[col].push(cell);
}
}
/* Deduce PostgreSQL type for each column */
const types = {};
headers.forEach((header, idx) => {
types[header] = deduceType(columnValues[idx]);
});
/* Delete table if it exists in the DB */
await client.query(format('DROP TABLE IF EXISTS %I', tableName));
/* Create table */
const createTableSQL = format(
'CREATE TABLE %I (%s)',
tableName,
headers.map(header => format('%I %s', header, types[header])).join(', ')
);
await client.query(createTableSQL);
/* Insert data row by row */
for (let row = range.s.r + 1; row <= range.e.r; row++) {
const values = headers.map((header, col) => {
const cellAddress = XLSX.utils.encode_cell({ r: row, c: col });
const cell = worksheet[cellAddress];
return parseValue(cell, types[header]);
});
const insertSQL = format(
'INSERT INTO %I (%s) VALUES (%s)',
tableName,
headers.map(h => format('%I', h)).join(', '),
values.map(() => '%L').join(', ')
);
await client.query(format(insertSQL, ...values));
}
}
module.exports = { sheet_to_pg_table };