YAML
Safe Loaders in Python Ruby and Java Compared and Tested
Which function to call in PyYAML, Ruby Psych and SnakeYAML to load untrusted YAML safely, what each default does and how to grep for the unsafe ones.
6 min read
Tag
how-to
590 posts
Excel
Removing Personal Data From an Excel File Before Sharing
Remove personal data from an Excel file before sharing: drop author properties, mask or delete columns, clear comments and rebuild a clean copy by script.
7 min read
XML
Modeling Lists and Optional Data in XML Without Surprises
Wrapper elements, empty versus absent versus nil, and the one-item list trap when XML becomes JSON, all demonstrated with real parser output.
6 min read
CSV
Reading a CSV in Swift on macOS and the CRLF Line Trap
Swift has no CSV parser in Foundation, and its String treats CRLF as one Character, so splitting on a newline fails. Parse bytes or use SwiftCSV.
9 min read
JSON
Unnesting JSON Arrays in BigQuery With JSON_QUERY_ARRAY
Turn a JSON array into rows in BigQuery with UNNEST and JSON_QUERY_ARRAY or JSON_VALUE_ARRAY, with positions, empty arrays, nesting and filters.
7 min read
Excel
Hidden Sheets and Metadata Leaking Out of Shared Workbooks
Find hidden sheets, document properties, comments, defined names and pivot caches in a workbook before you share it, with a script that audits the file.
7 min read
CSV
Reading a CSV File in Kotlin for a Quick Import Job
Read a CSV in Kotlin with kotlin-csv and build a small import job that validates rows, rejects bad ones with row numbers and never hides a failure.
11 min read
XML
Versioning an XML Format Without Breaking Existing Readers
Version attribute or new namespace? Test results show how strict schemas reject added elements and how an extension point lets old readers keep working.
6 min read
CSV
Reading CSV Files in Bash Without Breaking on Quotes
A bash read loop on a CSV breaks on quoted commas, backslashes, a missing last newline and empty tab fields. Let a CSV parser emit safe records first.
10 min read
YAML
Billion Laughs Style Attacks Through YAML Aliases Tested
Build a 378-byte YAML document that expands to 34 MB, measure PyYAML, DuckDB and Go on it, and see which parsers fail early and which wait for the output.
7 min read
JSON
Extracting JSON Fields in BigQuery With JSON_VALUE
Read JSON in BigQuery with JSON_VALUE, JSON_QUERY, field access and typed converters such as INT64(), with the null rules, SAFE prefix and lax conversion.
7 min read
CSV
Parsing CSV in Ruby With the CSV Library and Its Converters
Parse CSV in Ruby 3.4 with the csv gem: the Gemfile LoadError, a numeric converter that read 02134 as 1116, nil versus empty strings, and timings.
10 min read