My question is, does this count as a bug?
I'm not sure this can be called a bug. It is true (and perfectly
normal) that rendering a filesystem page template will always call the
CPM. You're rendering both here. Since output_page_2 is rendered last
as it's calles from output_page_1 the rule for output_page_2 fires and
will overwrite existing headers/add new headers according to the rule
That's got me thinking of some more potential examples of 'odd' behaviour:
(a) output_page_1 and output_page_2 both have rules associated that
apply the same headers (but different values):
the output will have the expected headers because output_page_1's rule
will fire last of all, overwriting the headers applied by output_page_2
(b) output_page_1 and output_page_2 both have rules associated applying
the output will be a mix of the headers applied by both rules, with
those applied due to output_page_1 taking precedence.
(c) only output_page_2 has a rule associated with it:
the output will contain headers applied due to output_page_2's rules,
whereas no headers are expected.
B and C are particularly frustrating, as there is no way to set a rule
that will remove the headers added by any other rule that might have
been fired previously. B seems particularly confusing to me (I am glad
it did not come up or I would still be investigating!). There might be
even more confusing interactions where 304s are enabled on some rules
but not others...
> The problem here is that both happen in the same request,
the rendering code does not distinguish betwen the primary and the
That's what I think the bug is: it should distinguish.
I've fixed it locally for me as follows:
- when a FSZPT is called, it looks for a request attribute (called
'template_count' or somesuch)
- if the attribute is present (i.e. it's a "subtemplate"), it adds one
to the value
- otherwise, it sets it to zero
- it carries on as normal to generate some output
- the request attribute is decreased
- the cpm is only called if the attribute is zero, as this indicates
the item is no longer a "subtemplate"
This works fine to suppress use of the cpm by any nested rendering.
Does it seem like a reasonable solution or is there a better way of
achieving the same thing? I cannot think of any simpler way of
detecting whether an item is the 'original' template or a 'subtemplate'
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