Resolving Althttpd Packaging Issues: URL Formatting, Versioning, and Checksum Inconsistencies
Althttpd Source URL Formatting and Versioning Challenges
When packaging althttpd for Alpine Linux, one of the primary challenges revolves around correctly formatting the source URL and ensuring consistent versioning. The initial approach involved using a date format (pkgver="05.09.2020") as the version number, which was later identified as problematic due to potential inconsistencies in how package managers interpret date-based versioning. The source URL was constructed using a specific check-in string (ci=ad2370ccce), which was intended to fetch a particular version of the althttpd source code. However, this approach raised questions about whether it would always fetch the same source corresponding to the version date listed in the pkgver variable.
The discussion revealed that using the ci= parameter in the URL might not be the most reliable method for fetching a specific version of the source code. Instead, it was suggested to use the r= parameter, which is more appropriate for referencing specific releases or check-ins. This confusion led to inconsistencies in the checksums of the downloaded files, as the ci= parameter might have been ignored, resulting in the latest trunk check-in being fetched instead of the intended version.
Additionally, the date format used for versioning was identified as a potential issue. The initial format (DD.MM.YYYY) could lead to misinterpretations by the package manager, especially when comparing versions. For example, 04.01.2019 might be incorrectly considered newer than 01.04.2020 due to the day and month being swapped. To avoid such issues, it was recommended to use the ISO-8601 standard (YYYYMMDD or YYYY-MM-DD), which ensures that dates are interpreted correctly and consistently.
Inconsistent Checksums Due to Filename and URL Parameter Misconfigurations
Another significant issue encountered during the packaging process was the inconsistency in checksums when downloading the althttpd source code. This inconsistency was traced back to the way filenames and URL parameters were configured. When specifying a filename in the URL (e.g., https://sqlite.org/docsrc/zip/althttpd.zip?ci=202005092232&in=misc/althttpd.c), the downloaded file’s name did not always match the intended filename, leading to confusion and mismatched checksums.
The discussion highlighted that the filename specified before the ? in the URL should ideally be the name of the downloaded file. However, this behavior was not consistent across different tools. For instance, when using Firefox, the filename was correctly interpreted, but when using Alpine’s build tools (which likely rely on wget), the filename was not preserved, resulting in the downloaded file being named althttpd.c instead of althttpd.zip. This discrepancy caused the checksums to differ, as the contents of the file were being interpreted differently based on the filename.
Furthermore, the use of the ci= parameter in the URL was identified as a potential source of confusion. When multiple URLs with the same filename but different ci= values were used, the checksums of the downloaded files were identical, even though the ci= values were different. This behavior suggested that the ci= parameter might have been ignored, leading to the same file being downloaded regardless of the specified check-in. This issue was resolved by switching to the r= parameter, which correctly fetched the intended version of the source code.
Implementing Correct URL Formatting and Versioning for Althttpd Packaging
To address the issues related to URL formatting, versioning, and checksum inconsistencies, several steps were recommended and implemented. First, the date format for the pkgver variable was updated to follow the ISO-8601 standard (YYYYMMDD or YYYY-MM-DD). This change ensured that the package manager would correctly interpret and compare version numbers, avoiding any potential misinterpretations due to differing date formats.
Next, the source URL was modified to use the r= parameter instead of the ci= parameter. This change ensured that the correct version of the source code was fetched, as the r= parameter is specifically designed to reference specific releases or check-ins. The updated URL format looked like this: https://sqlite.org/docsrc/zip/althttpd.zip?r=202005092232&in=misc/althttpd.c. This modification resolved the issue of inconsistent checksums, as the r= parameter correctly fetched the intended version of the source code.
Additionally, the filename in the URL was specified to ensure that the downloaded file would have the correct name. For example, the URL https://sqlite.org/docsrc/zip/althttpd-20200509.zip?r=202005092232&in=misc/althttpd.c would result in the file being downloaded as althttpd-20200509.zip. This approach ensured that the filename matched the intended version and avoided any confusion or mismatched checksums.
Finally, the Alpine build tools were configured to handle the renaming of the downloaded file correctly. Instead of relying on the filename specified in the URL, the build tools were set to rename the file using the pkgname and pkgver variables. This approach ensured that the downloaded file would always have a consistent name, regardless of the tool used to fetch it. The updated configuration looked like this: althttpd-20200509.zip::https://sqlite.org/docsrc/zip?r=202005092232&in=misc/althttpd.c.
By implementing these changes, the packaging process for althttpd was significantly improved, resulting in consistent checksums, correct versioning, and reliable source code downloads. These steps not only resolved the immediate issues but also provided a robust framework for future updates and maintenance of the althttpd package in Alpine Linux.
