When POET loads a page, references to resources on the page are stored in the page node (see _resourceLinks)
When a resource was removed from the bundle, perhaps via a filesystem event, the references in the page remained, even though the resources no longer existed in the bundle.
When a resource with the same absPath was created, it was added to the bundle again. This new resource instance, however, was distinct from the one that existed within the page, even though they pointed to the same content on the filesystem.
Until the page was updated, which causes the links to be reconstructed, resource links stored in the page did not correlate with the ones stored in the bundle. Consequently, the exists property of the resource node was not being updated
Solution:
Keep all nodes in the bundle
When a file referenced by a node is deleted from the filesystem, update the node's contents to undefined so that the node's exists property will be set to false
When a node that no longer exists on the file system is also orphaned, that node is removed
Possible problems & justifications:
~This technically introduces a memory leak where nodes continue to accumulate in the bundle forever; however, there are many ways this memory leak could be addressed if it becomes a real problem.~ Fixed by adding what is essentially garbage collection for orphaned nodes.
Out of all the approaches I explored, this one made the best use of Quarx, required the least number of changes, and exhibited the best performance.
fixes openstax/ce#2217
Problem:
When POET loads a page, references to resources on the page are stored in the page node (see _resourceLinks)
When a resource was removed from the bundle, perhaps via a filesystem event, the references in the page remained, even though the resources no longer existed in the bundle.
When a resource with the same absPath was created, it was added to the bundle again. This new resource instance, however, was distinct from the one that existed within the page, even though they pointed to the same content on the filesystem.
Until the page was updated, which causes the links to be reconstructed, resource links stored in the page did not correlate with the ones stored in the bundle. Consequently, the
existsproperty of the resource node was not being updatedSolution:
Keep all nodes in the bundle
When a file referenced by a node is deleted from the filesystem, update the node's contents to
undefinedso that the node'sexistsproperty will be set to falseWhen a node that no longer exists on the file system is also orphaned, that node is removed
Possible problems & justifications:
~This technically introduces a memory leak where nodes continue to accumulate in the bundle forever; however, there are many ways this memory leak could be addressed if it becomes a real problem.~ Fixed by adding what is essentially garbage collection for orphaned nodes.
Out of all the approaches I explored, this one made the best use of Quarx, required the least number of changes, and exhibited the best performance.