Over time the discussion about "lifecycle" blocks in the documentation
became confusing because the docs originally written for managed resource
lifecycle got partially generalized for resources of other modes and for
module calls, even though each of those has a completely different
lifecycle and thus a different set of lifecycle settings.
This is a first pass at trying to reorganize that so that the "lifecycle"
page is really just an index of all of the different kinds of lifecycle
block that exist in the language, while the main documentation for each
use of that block type now belongs with the documentation of the block
it's nested within.
While working on this I also found that there was some duplication inside
the "data sources" page where the same information was described multiple
times, and a few other cases where things had become inconsistent over
time. This also includes a little extra content to try to clarify the
difference between managed, data, and ephemeral resources and to make it
explicit that the "Resources" section is focused only on managed resources
because that is the primary resource mode.
As usual there's lots more that could be done here -- this documentation
has gradually evolved over time and is full of weird quirks due to that
evolution -- but I decided to draw a line here so that the diff wouldn't
get too large.
Signed-off-by: Martin Atkins <mart@degeneration.co.uk>
When a data resource is used for the purposes of verifying a condition
about an object managed elsewhere (e.g. if the managed resource doesn't
directly export all of the information required for the condition) it's
important that we defer the data resource read to the apply step if the
corresponding managed resource has any changes pending.
Typically we'd expect that to come "for free" but unfortunately we have
a pragmatic special case in our handling of data resources where we
normally defer to the apply step only if a _direct_ dependency of the data
resource has a change pending, and allow a plan-time read if there's
a pending change in an indirect dependency. This allowed us to preserve
some compatibility with the questionable historical behavior of always
reading data resources proactively unless the configuration contains
unknown values, since the arguably-more-correct behavior would've been a
regression for anyone who had been depending on that before.
Since preconditions and postconditions didn't exist until now, we are not
constrained in the same way by backward compatibility, and so we can adopt
the more correct behavior in the case where a data resource has conditions
specified. This does unfortunately make the handling of data resources
with conditions subtly inconsistent with those that don't, but this is
a better situation than the alternative where it would be easy to get into
a trapped situation where the remote system is invalid and it's impossible
to plan the change that would make it valid again because the conditions
evaluate too soon, prior to the fix being applied.
* website: Update or remove references to legacy provider docs
We've finally evicted the last of the legacy provider docs from terraform.io!
Let's celebrate by purging all memory of them.
The 0.11 docs are now so thoroughly legacy that I don't believe they need a new
destination for their provider links, so I just removed those.
* website: remove old provider docs index
This will require a redirect in the terraform-website repo.
* Apply suggestions from code review
Co-authored-by: Laura Pacilio <83350965+laurapacilio@users.noreply.github.com>
Co-authored-by: Laura Pacilio <83350965+laurapacilio@users.noreply.github.com>
* clarify input variables opening sentence
* adjust variables description
* claraify providers text and add learn callout
* add description to providers page
* add desscription and clarify provider configuration
* add deprecation note to versions in proivder configs
* add hands on callout and clarify next steps in intro
* link to language collection from language docs
* give more context about configurtion language up front
* clarify output top page
* reorganize for each intro to present feature before notes
* move description before link out and remove passive voice
* fix typo
* clarify purpose of plan
* move explanation before learn link and fully spell boolean
* add a syntax heading to separate intro from details
* add learn callout to module source docs
* clean up intro to provider requirements and add link
* Apply suggestions from code review
Co-authored-by: Tu Nguyen <im2nguyen@users.noreply.github.com>
* Apply suggestions from code review
Co-authored-by: Tu Nguyen <im2nguyen@users.noreply.github.com>
Co-authored-by: Tu Nguyen <im2nguyen@users.noreply.github.com>
