Steps

Enhancement

As part of the fallout of #10379, we wanted to further shore up our testing around buffers to ideally prevent us (me) for inadvertently changing things and not noticing... like the buffer data directory.

To that end, the PR to address #10895 is simple, but we're doing our due diligence here by re-running tests that are more or less identical to what we did for #10430, so that we can feel confident that our changes here haven't yet again introduced a regression.

Testing Plan

Start by grabbing Vector binaries for 0.18.1 and 0.19.1, and build one from the PR branch. We'll use the same configuration as the testing for #10430, which is a stdin source and HTTP sink, although we won't actually use them. In this case, we just need a valid configuration that will also create a buffer.

Test Case(s)

1. Establish a baseline of ther "old to new" migration behavior from 0.18.1 to 0.19.1:
   • Run the 0.18.1 binary with a clean data directory and ensure it creates the old-style buffer data directory, but don't send any data through.
   • Run the PR binary and ensure that it renames the old-style buffer data directory to the new-style buffer data directory. Again, send no data through.
   • No other data directories for the buffer should exist.
2. Ensure that the "old to new" migration logic still works from 0.18.1 (old) to the PR (new) version:
   • Run the 0.18.1 binary with a clean data directory and ensure it creates the old-style buffer data directory, but don't send any data through.
   • Run the PR binary and ensure that it renames the old-style buffer data directory to the new-style buffer data directory. Again, send no data through.
   • No other data directories for the buffer should exist.
   • Crucially, each step should appear identical to the output in test case #1.
3. Ensure that the "new" style name still holds through from 0.19.1 to the PR version:
   • Run the 0.19.1 binary with a clean data directory and ensure it creates the new-style buffer data directory, but don't send any data through.
   • Run the PR binary and ensure that it leaves the data directory, as created by the 0.19.1 binary, as is, in terms of naming.
   • No other data directories for the buffer should exist.