This form of "terraform init" is vestigial at this point and being phased
out in 0.10. Something similar may return in a later version for
installing modules from a more formal module library, but for now we are
advising to use git manually to simplify the UX for "terraform init".
Each provider plugin will take at least a few seconds to download, so
providing feedback about each one should make users feel less like
Terraform has hung.
Ideally we'd show ongoing progress during the download, but that's not
possible without re-working go-getter, so we'll accept this as an interim
solution for now.
The information stored in a plan is tightly coupled to the Terraform core
and provider plugins that were used to create it, since we have no
mechanism to "upgrade" a plan to reflect schema changes and so mismatching
versions are likely to lead to the "diffs didn't match during apply"
error.
To allow us to catch this early and return an error message that _doesn't_
say it's a bug in Terraform, we'll remember the Terraform version and
plugin binaries that created a particular plan and then require that
those match when loading the plan in order to apply it.
The planFormatVersion is increased here so that plan files produced by
earlier Terraform versions _without_ this information won't be accepted
by this new version, and also that older versions won't try to process
plans created by newer versions.
This was added with the idea of using it to override the SHA256 hashes
to match those hypothetically stored in a plan, but we already have a
mechanism elsewhere for populating context fields from plan fields, so
this is not actually necessary.
When running "terraform init" with providers that are unconstrained, we
will now produce information to help the user update configuration to
constrain for the particular providers that were chosen, to prevent
inadvertently drifting onto a newer major release that might contain
breaking changes.
A ~> constraint is used here because pinning to a single specific version
is expected to create dependency hell when using child modules. By using
this constraint mode, which allows minor version upgrades, we avoid the
need for users to constantly adjust version constraints across many
modules, but make major version upgrades still be opt-in.
Any constraint at all in the configuration will prevent the display of
these suggestions, so users are free to use stronger or weaker constraints
if desired, ignoring the recommendation.
Previously we were using the "semver" library to parse version
constraints, but we switched over to go-version and encapsulated it
inside our own plugin/discovery package to reduce dependency sprawl in
the code.
This particular situation was missed when updating references to the new
path, which meant that our validation code disagreed with the rest of
the code about what is considered a valid version constraint string.
By using the correct function, we ensure that we catch early any invalid
versions.
We can filter the allowed versions and sort them before checking the
protocol version, that way we can just return the first one found
reducing network requests.
Extend the test reslease server to return the protocol version header
and a dummy zip file for the provider.
Test filtering the plugins by plugin protocol version and add a full
GetProvder test.
Get provider needs to be provided with the plugin protocol version,
because it can't be imported here directly.
The plugin url types and methods were confusing; replace them with a few
functions to format the urls.
Once we've installed the necessary plugins, we'll do one more walk of
the available plugins and record the SHA256 hashes of all of the plugins
we select in the provider lock file.
The file we write here gets read when we're building ContextOpts to
initialize the main terraform context, so any command that works with
the context will then fail if any of the provider binaries change.
This is used to mark the plugin protocol version. Currently we actually
just ignore this entirely, since only one protocol version exists anyway.
Later we will need to add checks here to ensure that we only pay attention
to plugins of the right version.
By reading our lock file and passing this into the context, we ensure that
only the plugins referenced in the lock file can be used. As of this
commit there is no way to create that lock file, but that will follow soon
as part of "terraform init".
We also provide a way to force a particular set of SHA256s. The main use
for this is to allow us to persist a set of plugins in the plan and
check the same plugins are used during apply, but it may also be useful
for automated tests.
When set, this information gets passed on to the provider resolver as
part of the requirements information, causing us to reject any plugins
that do not match during initialization.
As well as constraining plugins by version number, we also want to be
able to pin plugins to use specific executables so that we can detect
drift in available plugins between commands.
This commit allows such requirements to be specified, but doesn't yet
specify any such requirements, nor validate them.
Previously we encouraged users to import a resource and _then_ write the
configuration block for it. This ordering creates lots of risk, since
for various reasons users can end up subsequently running Terraform
without any configuration in place, which then causes Terraform to want
to destroy the resource that was imported.
Now we invert this and require a minimal configuration block be written
first. This helps ensure that the user ends up with a correlated resource
config and state, protecting against any inconsistency caused by typos.
This addresses #11835.
Previously we deferred validation of the resource address on the import
command until we were in the core guts, which caused the error responses
to be rather unhelpful.
By validating these things early we can give better feedback to the user.
For some reason there was a block of commented-out tests for the refresh
command in the test file for the import command. Here we remove them to
reduce the noise in this file.
Previously one of the errors had a built-in context message and the other
did not, making it hard for callers to present a user-friendly message
in both cases.
Now we generate an error message of the same form in both cases, with one
case providing additional information. Ideally the main case would be
able to give more specific guidance too, but that's hard to achieve with
the current regexp-based parsing implementation.
This is a useful building block for filtering configuration based on a
resource address. It is similar in principle to state filtering, but for
specific resource configuration blocks.
This allows growing the scope of a resource address to include all of the
resources in the same module as the targeted resource. This is useful to
give context in error messages.
The resource address documentation defines a resource address as being in
two parts: the module path and the resource spec. The resource spec can
be omitted, which represents addressing _all_ resources in a module.
In some cases (such as import) it doesn't make sense to address an entire
module, so this helper makes it easy for validation code to check for
this to reject insufficiently-specific resource addresses.
Add discovery.GetProviders to fetch plugins from the relases site.
This is an early version, with no tests, that only (probably) fetches
plugins from the default location. The URLs are still subject to change,
and since there are no plugin releases, it doesn't work at all yet.
Instead of providing the a path in BackendOpts, provide a loaded
*config.Config instead. This reduces the number of places where
configuration is loaded.
This will be fleshed out later as part of more holistic documentation for
the new provider plugin separation, but this is some minimal documentation
for just this subcommand.
This new command prints out the tree of modules annotated with their
associated required providers.
The purpose of this command is to help users answer questions such as
"why is this provider required?", "why is Terraform using an older version
of this provider?", and "what combination of modules is creating an
impossible provider version situation?"
For configurations using many modules this sort of question is likely to
come up a lot once we support versioned providers.
As a bonus use-case, this command also shows explicitly when a provider
configuration is being inherited from a parent module, to help users to
understand where the configuration is coming from for each module when
some child modules provide their own provider configurations.
We're going to use config to determine provider dependencies, so we need
to always provide a config when instantiating a context or we'll end up
loading no providers at all.
We previously had a test for running "terraform import -config=''" to
disable the config entirely, but this test is now removed because it makes
no sense. The actual functionality its testing still remains for now,
but it will be removed in a subsequent commit when we start requiring that
a resource to be imported must already exist in configuration.
Rather than providing an already-resolved map of plugins to core, we now
provide a "provider resolver" which knows how to resolve a set of provider
dependencies, to be determined later, and produce that map.
This requires the context to be instantiated in a different way, so this
very noisy diff is a mostly-mechanical update of all of the existing
places where contexts get created for testing, using some adapted versions
of the pre-existing utilities for passing in mock providers.
Previously the set of providers was fixed early on in the command package
processing. In order to be version-aware we need to defer this work until
later, so this interface exists so we can hold on to the possibly-many
versions of plugins we have available and then later, once we've finished
determining the provider dependencies, select the appropriate version of
each provider to produce the final set of providers to use.
This commit establishes the use of this new mechanism, and thus populates
the provider factory map with only the providers that result from the
dependency resolution process.
This disables support for internal provider plugins, though the
mechanisms for building and launching these are still here vestigially,
to be cleaned up in a subsequent commit.
This also adds a new awkward quirk to the "terraform import" workflow
where one can't import a resource from a provider that isn't already
mentioned (implicitly or explicitly) in config. We will do some UX work
in subsequent commits to make this behavior better.
This breaks many tests due to the change in interface, but to keep this
particular diff reasonably easy to read the test fixes are split into
a separate commit.
ResourceProviderResolver is an extra level of indirection before we
get to a map[string]ResourceProviderFactory, which accepts a map of
version constraints and uses it to choose from potentially-many available
versions of each provider to produce a single ResourceProviderFactory
for each one requested.
As of this commit the ResourceProviderResolver interface is not used. In
a future commit the ContextOpts.Providers map will be replaced with a
resolver instance, with the creation of the factory delayed until the
version constraints have been resolved.
Currently this doesn't matter much, but we're about to start checking the
availability of providers early on and so we need to use the correct name
for the mock set of providers we use in command tests, which includes
only a provider named "test".
Without this change, the "push" tests will begin failing once we start
verifying this, since there's no "aws" provider available in the test
context.
Previously having a config was mutually exclusive with running an import,
but we need to provide a config so that the provider is declared, or else
we can't actually complete the import in the future world where providers
are installed dynamically based on their declarations.
Martin Atkins