Tenant-Aware Caching Without Data Leaks
Design multi-tenant cache keys, invalidation, authorization boundaries, and per-tenant limits so cached data cannot leak between SaaS customers.
Month: September 2026
Soft Delete Strategy for Multi-Tenant SaaS
Design tenant-scoped soft deletes with deleted timestamps, filtered queries, uniqueness rules, restoration, retention, and permanent purge jobs.
Download Generated Text as a File with JavaScript
Create a client-side text or CSV download with Blob, an object URL, the download attribute, UTF-8 handling, and timely URL cleanup.
Resize an Image Before Upload with JavaScript
Resize a selected browser image with createImageBitmap and canvas, preserve aspect ratio, export a Blob, and upload the smaller file.
Prevent Duplicate Form Submission in JavaScript
Disable a form’s submit controls after a valid submission, show progress, handle failed asynchronous requests, and still enforce idempotency on the server.
Validate Image Dimensions Before Upload with JavaScript
Check an image file’s intrinsic width and height before upload using createImageBitmap, while keeping server-side validation as the security boundary.
Detect and Repair Double-Encoded UTF-8 Text
Recognize common double-encoded UTF-8 patterns, reverse a known Windows-1252 mis-decoding in PHP, and avoid corrupting already-correct rows.
Unicode Normalization: NFC vs NFD
Understand why visually identical Unicode strings can compare differently and when to normalize text to NFC or NFD in JavaScript and databases.
Fix Invalid UTF-8 Errors in JSON
Find and repair malformed UTF-8 before JSON encoding in PHP, preserve error visibility, and avoid silently discarding corrupted input.
Fix Mojibake After a MySQL Migration
Diagnose and repair garbled text after a MySQL migration by separating stored bytes, column metadata, connection character sets, and application output.