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cloudfront-viewer-country-name stopped working in AWS

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Summary Between November 18th and 21st, Lambda functions behind CloudFront stopped receiving CloudFront-Viewer-Country-Name headers while CloudFront-Viewer-Country continued to function. The root cause was a change in how CloudFront handles country header formatting. AWS silently changed the format of geolocation headers from hyphenated (CloudFront-Viewer-Country-Name) to lowercase with spaces replaced by underscores (CloudFront-Viewer-Country-Name became CloudFront-Viewer-Country-Name). The Viewer … Read more

Performance of square root calculation – expectation versus reality

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Summary A user-level benchmark suggests that math.sqrt(x) is approximately 20% faster than x**0.5 for calculating square roots in Python. While both operations are mathematically equivalent for positive numbers, the performance difference stems from how the Python interpreter and underlying C libraries handle these operations. math.sqrt maps directly to a low-level C library call optimized specifically … Read more

How to swap multiple variables using multiple assignment?

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Summary The problem revolves around understanding how multiple assignment works in Python, particularly when swapping values of multiple variables. The key takeaway is that Python’s multiple assignment is a simultaneous operation, meaning all assignments happen at the same time. Root Cause The root cause of confusion lies in misunderstanding the order of operations during multiple … Read more

Handling text input width and making it responsive

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Summary The core problem is a mismatch between a fixed-size CSS container and dynamic user input. The developer used a width: 25vw rule on the input, which is a rigid measurement. When the user enters numbers with many digits, the input container stays the same physical width, but the font size is large. Since text-wrap: … Read more

Some users cannot type anything

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Summary A critical input failure occurs where some users cannot type into a JTextArea within a JAR deployment, while the same code works in development environments. The root cause is a blocking EDT (Event Dispatch Thread) behavior triggered by the heavy KeyListener logic, causing the UI thread to freeze intermittently or under specific system conditions … Read more

Autodesk Forge Viewer: setGhosting() + isolate() not making elements transparent – topography transparency issue

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Summary During a feature implementation for a “Transparent Topography” button in Autodesk Forge Viewer v7.x, the expected ghosting behavior failed. The goal was to make FBX topography elements transparent while keeping Revit (RVT) and Navisworks (NWD/NWC) elements opaque. The implementation relied on setGhosting(true) combined with isolate() on non-FBX elements. The result was inconsistent: sometimes FBX … Read more

Dapper fails calling a Stored Procedure that builds a Dynamic SQL statement

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Summary A .NET REST API using Dapper fails to execute a specific Azure SQL Stored Procedure that constructs a dynamic SQL string in a single statement. The Stored Procedure works correctly when called via SSMS, OLEDB, and an older Entity Framework-based API. Splitting the string concatenation for the dynamic SQL into multiple statements resolves the … Read more

somehow it just showing error all of sudden

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Summary The issue at hand is related to the google_fonts package in a Flutter application, specifically version ^6.2.1. The error message indicates that the package is unable to load the font Inter-SemiBold due to an exception occurring when trying to load the AssetManifest.json asset. This results in an Unhandled Exception and breaks the application. Root … Read more