Previously this codepath was generating a confusing message in the absense
of any symlinks, because filepath.EvalSymlinks returns a successful result
if the target isn't a symlink.
Now we'll emit the log line only if filepath.EvalSymlinks returns a
result that's different in a way that isn't purely syntactic (which
filepath.Clean would "fix").
The new message is a little more generic because technically we've not
actually ensured that a difference here was caused by a symlink and so
we shouldn't over-promise and generate something potentially misleading.
The SearchLocalDirectory function was intentionally written to only
support symlinks at the leaves so that it wouldn't risk getting into an
infinite loop traversing intermediate symlinks, but that rule was also
applying to the base directory itself.
It's pretty reasonable to put your local plugins in some location
Terraform wouldn't normally search (e.g. because you want to get them from
a shared filesystem mounted somewhere) and creating a symlink from one
of the locations Terraform _does_ search is a convenient way to help
Terraform find those without going all in on the explicit provider
installation methods configuration that is intended for more complicated
situations.
To allow for that, here we make a special exception for the base
directory, resolving that first before we do any directory walking.
In order to help with debugging a situation where there are for some
reason symlinks at intermediate levels inside the search tree, we also now
emit a WARN log line in that case to be explicit that symlinks are not
supported there and to hint to put the symlink at the top-level if you
want to use symlinks at all.
(The support for symlinks at the deepest level of search is not mentioned
in this message because we allow it primarily for our own cache linking
behavior.)
This is the equivalent of UnpackedDirectoryPathForPackage when working
with the packed directory layout. It returns a path to a .zip file with
a name that would be detected by SearchLocalDirectory as a
PackageLocalArchive package.
* internal/getproviders: fix panic with invalid path parts
If the search path is missing a directory, the provider installer would
try to create an addrs.Provider with the wrong parts. For example if the
hostname was missing (as in the test case), it would call
addrs.NewProvider with (namespace, typename, version). This adds a
validation step for each part before calling addrs.NewProvider to avoid
the panic.
Previously this was failing to treat symlinks to directories as unpacked
layout, because our file info was only an Lstat result, not a full Stat.
Now we'll resolve the symlink first, allowing us to handle a symlink to
a directory. That's important because our internal/providercache behavior
is to symlink from one cache to another where possible.
There's a lot going on in these functions that can be hard to follow from
the outside, so we'll add some additional trace logging so that we can
more easily understand why things are behaving the way they are.
The existing functionality in this package deals with finding packages
that are either available for installation or already installed. In order
to support installation we also need to determine the location where a
package should be installed.
This lives in the getproviders package because that way all of the logic
related to the filesystem layout for local provider directories lives
together here where they can be maintained together more easily in future.
Previously this was available by instantiating a throwaway
FilesystemMirrorSource, but that's pretty counter-intuitive for callers
that just want to do a one-off scan without retaining any ongoing state.
Now we expose SearchLocalDirectory as an exported function, and the
FilesystemMirrorSource then uses it as part of its implementation too.
Callers that just want to know what's available in a directory can call
SearchLocalDirectory directly.
Alex Chan