Move the code which renders Terraform hook callbacks as UI into the
views package, backed by a views.View instead of a cli.Ui. Update test
setup accordingly.
To allow commands to control this hook, we add a hooks member on the
backend Operation struct. This supersedes the hooks in the Terraform
context, which is not directly controlled by the command logic.
This commit should not change how Terraform works, and is refactoring in
preparation for more changes which move UI code out of the backend.
Rather than modifying and relying on the existing Meta.process
argument extractor, we can more clearly handle global CLI flags using
a separate parser step. This allows us to explicitly configure the view
in the command.
Terraform supports multiple output formats for several sub-commands.
The default format is user-readable text, but many sub-commands support
a `-json` flag to output a machine-readable format for the result. The
output command also supports a `-raw` flag for a simpler, scripting-
focused machine readable format.
This commit adds a "views" abstraction, intended to help ensure
consistency between the various output formats. This extracts the render
specific code from the command package, and moves it into a views
package. Each command is expected to create an interface for its view,
and one or more implementations of that interface.
By doing so, we separate the concerns of generating the sub-command
result from rendering the result in the specified output format. This
should make it easier to ensure that all output formats will be updated
together when changes occur in the result-generating phase.
There are some other consequences of this restructuring:
- Views now directly access the terminal streams, rather than the
now-redundant cli.Ui instance;
- With the reorganization of commands, parsing CLI arguments is now the
responsibility of a separate "arguments" package.
For now, views are added only for the output sub-command, as an example.
Because this command uses code which is shared with the apply and
refresh commands, those are also partially updated.
Errors encountered when parsing flags for apply, plan, and refresh were
being suppressed. This resulted in a generic usage error when using an
invalid `-target` flag.
This commit makes several changes to address this. First, these commands
now output the flag parse error before exiting, leaving at least some
hint about the error. You can verify this manually with something like:
terraform apply -invalid-flag
We also change how target attributes are parsed, moving the
responsibility from the flags instance to the command. This allows us to
customize the diagnostic output to be more user friendly. The
diagnostics now look like:
```shellsession
$ terraform apply -no-color -target=foo
Error: Invalid target "foo"
Resource specification must include a resource type and name.
```
Finally, we add test coverage for both parsing of target flags, and at
the command level for successful use of resource targeting. These tests
focus on the UI output (via the change summary and refresh logs), as the
functionality of targeting is covered by the context tests in the
terraform package.
Commit e865faf adds visual indentation for diagnostic messages using various
vertical line characters. The present commit disables this behaviour when
running with colourised output disabled.
While the contents of stderr are not intended to be part of the Terraform API,
this is currently how the hashicorp/terraform-exec library detects certain
error types in order to present them as well-known Go errors to the user. Such
detection is complicated when vertical lines are added to the CLI output at
unpredictable points.
I expect this change will also be helpful for screen reader users.
I frequently see people attempting to ask questions about Terraform's
error and warning messages but either only copying part of the message or
accidentally copying a surrounding paragraph that isn't part of the
message.
While I'm sure some of these are just "careless" mistakes, I've also
noticed that this has sometimes overlapped with someone asking a question
whose answer is written directly in the part of the message they didn't
include when copying, and so I have a theory that our current output
doesn't create a good enough visual hierarchy for sighted users to
understand where the diagnostic messages start and end when we show them
in close proximity to other content, or to other diagnostic messages.
As a result, some folks fail to notice the relevant message that might've
answered their question.
I tried a few different experiments for different approaches here, such
as adding more horizontal rules to the output and coloring the detail
text differently, but the approach that felt like the nicest compromise
to me was what's implemented here, which is to add a vertical line
along the left edge of each diagnostic message, colored to match with the
typical color we use for each diagnostic severity. This means that the
diagnostics end up slightly indented from what's around them, and the
vertical line seems to help subtly signal how we intended the content
to be grouped together.
We now require the output to accept UTF-8 and we can determine how wide
the terminal (if any) is, so here we begin to make use of that for the
"terraform plan" command.
The horizontal rule is now made of box drawing characters instead of
hyphens and fills the whole terminal width.
The paragraphs of text in the output are now also wrapped to fill the
terminal width, instead of the hard-wrapping we did before.
This is just a start down the road of making better use of the terminal
capabilities. Lots of other commands could benefit from updates like these
too.
Here we propagate in the initialized terminal.Streams from package main,
and then onwards to backends running in CLI mode.
This also replaces our use of helper/wrappedstreams to determine whether
stdin is a terminal or a pipe. helper/wrappedstreams returns incorrect
file descriptors on Windows, causing StdinPiped to always return false on
that platform and thus causing one of the odd behaviors discussed in
Finally, this includes some wrappers around the ability to look up the
number of columns in the terminal in preparation for use elsewhere. These
wrappers deal with the fact that our unit tests typically won't populate
meta.Streams.
* command/format: concise diff is no longer an experiment
Since state formatting goes through the "diff" printer, I have
repurposed the concise flag as a verbose flag, used only when printing
state. It's silly but it works!
* remove helper/experiment
With this experiment concluded, we no longer need helper/experiment. The
shadow experiment had not been touched in many years, so I removed all
references, and removed the package entirely. Any new experiments are
expected to be configuration experiments handled by our (other)
experiments package.
* check for the verbose flag consistently, in case we end up using it in plans in the future
When using the enhanced remote backend, a subset of all Terraform
operations are supported. Of these, only plan and apply can be executed
on the remote infrastructure (e.g. Terraform Cloud). Other operations
run locally and use the remote backend for state storage.
This causes problems when the local version of Terraform does not match
the configured version from the remote workspace. If the two versions
are incompatible, an `import` or `state mv` operation can cause the
remote workspace to be unusable until a manual fix is applied.
To prevent this from happening accidentally, this commit introduces a
check that the local Terraform version and the configured remote
workspace Terraform version are compatible. This check is skipped for
commands which do not write state, and can also be disabled by the use
of a new command-line flag, `-ignore-remote-version`.
Terraform version compatibility is defined as:
- For all releases before 0.14.0, local must exactly equal remote, as
two different versions cannot share state;
- 0.14.0 to 1.0.x are compatible, as we will not change the state
version number until at least Terraform 1.1.0;
- Versions after 1.1.0 must have the same major and minor versions, as
we will not change the state version number in a patch release.
If the two versions are incompatible, a diagnostic is displayed,
advising that the error can be suppressed with `-ignore-remote-version`.
When this flag is used, the diagnostic is still displayed, but as a
warning instead of an error.
Commands which will not write state can assert this fact by calling the
helper `meta.ignoreRemoteBackendVersionConflict`, which will disable the
checks. Those which can write state should instead call the helper
`meta.remoteBackendVersionCheck`, which will return diagnostics for
display.
In addition to these explicit paths for managing the version check, we
have an implicit check in the remote backend's state manager
initialization method. Both of the above helpers will disable this
check. This fallback is in place to ensure that future code paths which
access state cannot accidentally skip the remote version check.
When building a context, we read the dependency locks and ensure that
the provider requirements from the configuration can be satisfied.
If the configured requirements change such that the locks need to be
updated, we explain this and recommend running "terraform init".
This check is ignored for any providers which are locally marked as in
development. This includes unmanaged providers and those listed in the
provider installation `dev_overrides` block.
For normal provider installation we want to associate each provider with
a selected version number and find a suitable package for that version
that conforms to the official hashes for that release.
Those requirements are very onerous for a provider developer currently
testing a not-yet-released build, though. To allow for that case this new
CLI configuration feature allows overriding specific providers to refer
to give local filesystem directories.
Any provider overridden in this way is not subject to the usual
restrictions about selected versions or checksum conformance, and
activating an override won't cause any changes to the selections recorded
in the lock file because it's intended to be a temporary setting for one
developer only.
This is, in a sense, a spiritual successor of an old capability we had to
override specific plugins in the CLI configuration file. There were
some vestiges of that left in the main package and CLI config package
but nothing has actually been honoring them for several versions now and
so this commit removes them to avoid confusion with the new mechanism.
This changes the approach used by the provider installer to remember
between runs which selections it has previously made, using the lock file
format implemented in internal/depsfile.
This means that version constraints in the configuration are considered
only for providers we've not seen before or when -upgrade mode is active.
In earlier commits we started to make the installation codepath
context-aware so that it could be canceled in the event of a SIGINT, but
we didn't complete wiring that through the API of the getproviders
package.
Here we make the getproviders.Source interface methods, along with some
other functions that can make network requests, take a context.Context
argument and act appropriately if that context is cancelled.
The main providercache.Installer.EnsureProviderVersions method now also
has some context-awareness so that it can abort its work early if its
context reports any sort of error. That avoids waiting for the process
to wind through all of the remaining iterations of the various loops,
logging each request failure separately, and instead returns just
a single aggregate "canceled" error.
We can then set things up in the "terraform init" and
"terraform providers mirror" commands so that the context will be
cancelled if we get an interrupt signal, allowing provider installation
to abort early while still atomically completing any local-side effects
that may have started.
This new option is intended to address the previous inconsistencies where
some older subcommands supported partially changing the target directory
(where Terraform would use the new directory inconsistently) where newer
commands did not support that override at all.
Instead, now Terraform will accept a -chdir command at the start of the
command line (before the subcommand) and will interpret it as a request
to direct all actions that would normally be taken in the current working
directory into the target directory instead. This is similar to options
offered by some other similar tools, such as the -C option in "make".
The new option is only accepted at the start of the command line (before
the subcommand) as a way to reflect that it is a global command (not
specific to a particular subcommand) and that it takes effect _before_
executing the subcommand. This also means it'll be forced to appear before
any other command-specific arguments that take file paths, which hopefully
communicates that those other arguments are interpreted relative to the
overridden path.
As a measure of pragmatism for existing uses, the path.cwd object in
the Terraform language will continue to return the _original_ working
directory (ignoring -chdir), in case that is important in some exceptional
workflows. The path.root object gives the root module directory, which
will always match the overriden working directory unless the user
simultaneously uses one of the legacy directory override arguments, which
is not a pattern we intend to support in the long run.
As a first step down the deprecation path, this commit adjusts the
documentation to de-emphasize the inconsistent old command line arguments,
including specific guidance on what to use instead for the main three
workflow commands, but all of those options remain supported in the same
way as they were before. In a later commit we'll make those arguments
produce a visible deprecation warning in Terraform's output, and then
in an even later commit we'll remove them entirely so that -chdir is the
single supported way to run Terraform from a directory other than the
one containing the root module configuration.
The workspace name can be overridden by setting a TF_WORKSPACE
environment variable. If this is done, we should still validate the
resulting workspace name; otherwise, we could end up with an invalid and
unselectable workspace.
This change updates the Meta.Workspace function to return an error, and
handles that error wherever necessary.
This adds supports for "unmanaged" providers, or providers with process
lifecycles not controlled by Terraform. These providers are assumed to
be started before Terraform is launched, and are assumed to shut
themselves down after Terraform has finished running.
To do this, we must update the go-plugin dependency to v1.3.0, which
added support for the "test mode" plugin serving that powers all this.
As a side-effect of not needing to manage the process lifecycle anymore,
Terraform also no longer needs to worry about the provider's binary, as
it won't be used for anything anymore. Because of this, we can disable
the init behavior that concerns itself with downloading that provider's
binary, checking its version, and otherwise managing the binary.
This is all managed on a per-provider basis, so managed providers that
Terraform downloads, starts, and stops can be used in the same commands
as unmanaged providers. The TF_REATTACH_PROVIDERS environment variable
is added, and is a JSON encoding of the provider's address to the
information we need to connect to it.
This change enables two benefits: first, delve and other debuggers can
now be attached to provider server processes, and Terraform can connect.
This allows for attaching debuggers to provider processes, which before
was difficult to impossible. Second, it allows the SDK test framework to
host the provider in the same process as the test driver, while running
a production Terraform binary against the provider. This allows for Go's
built-in race detector and test coverage tooling to work as expected in
provider tests.
Unmanaged providers are expected to work in the exact same way as
managed providers, with one caveat: Terraform kills provider processes
and restarts them once per graph walk, meaning multiple times during
most Terraform CLI commands. As unmanaged providers can't be killed by
Terraform, and have no visibility into graph walks, unmanaged providers
are likely to have differences in how their global mutable state behaves
when compared to managed providers. Namely, unmanaged providers are
likely to retain global state when managed providers would have reset
it. Developers relying on global state should be aware of this.
Back when we first introduced provider versioning in Terraform 0.10, we
did the provider version resolution in terraform.NewContext because we
weren't sure yet how exactly our versioning model was going to play out
(whether different versions could be selected per provider configuration,
for example) and because we were building around the limitations of our
existing filesystem-based plugin discovery model.
However, the new installer codepath is new able to do all of the
selections up front during installation, so we don't need such a heavy
inversion of control abstraction to get this done: the command package can
select the exact provider versions and pass their factories directly
to terraform.NewContext as a simple static map.
The result of this commit is that CLI commands other than "init" are now
able to consume the local cache directory and selections produced by the
installation process in "terraform init", passing all of the selected
providers down to the terraform.NewContext function for use in
implementing the main operations.
This commit is just enough to get the providers passing into the
terraform.Context. There's still plenty more to do here, including to
repair all of the tests this change has additionally broken.
Following the same approach we use for other CLI-Config-able objects like
the service discovery system, the main package is responsible for
producing a suitable implementation of this interface which the command
package can then use.
When unit testing in the command package we can then substitute mocks as
necessary, following the dependency inversion principle.
When warnings appear in isolation (not accompanied by an error) it's
reasonable to want to defer resolving them for a while because they are
not actually blocking immediate work.
However, our warning messages tend to be long by default in order to
include all of the necessary context to understand the implications of
the warning, and that can make them overwhelming when combined with other
output.
As a compromise, this adds a new CLI option -compact-warnings which is
supported for all the main operation commands and which uses a more
compact format to print out warnings as long as they aren't also
accompanied by errors.
The default remains unchanged except that the threshold for consolidating
warning messages is reduced to one so that we'll now only show one of
each distinct warning summary.
Full warning messages are always shown if there's at least one error
included in the diagnostic set too, because in that case the warning
message could contain additional context to help understand the error.
Some of our warnings are produced in response to particular configuration
constructs which might appear many times across a Terraform configuration.
To avoid the warning output dwarfing all of the other output, we'll use
ConsolidateWarnings to limit each distinct warning summary to appear at
most twice, and annotate the final one in the sequence with an additional
paragraph noting that some number of them have been hidden.
This is intended as a compromise to ensure that these warnings are still
seen and noted but to help ensure that we won't produce so many of them
as to distract from other output that appears alongside them.
This applies only to warnings relating to specific configuration ranges;
errors will continue to be shown individually, and sourceless warnings
(which are rare in Terraform today) will likewise remain ungrouped because
they are less likely to be repeating the same statement about different
instances of the same problem throughout the configuration.
During the 0.12 work we intended to move all of the variable value
collection logic into the UI layer (command package and backend packages)
and present them all together as a unified data structure to Terraform
Core. However, we didn't quite succeed because the interactive prompts
for unset required variables were still being handled _after_ calling
into Terraform Core.
Here we complete that earlier work by moving the interactive prompts for
variables out into the UI layer too, thus allowing us to handle final
validation of the variables all together in one place and do so in the UI
layer where we have the most context still available about where all of
these values are coming from.
This allows us to fix a problem where previously disabling input with
-input=false on the command line could cause Terraform Core to receive an
incomplete set of variable values, and fail with a bad error message.
As a consequence of this refactoring, the scope of terraform.Context.Input
is now reduced to only gathering provider configuration arguments. Ideally
that too would move into the UI layer somehow in a future commit, but
that's a problem for another day.
For unit testing in particular we can't launch a real browser for testing,
so this indirection is primarily to allow us to substitute a mock when
testing a command that can launch a browser.
This includes a simple mock implementation that expects to interact with
a running web server directly.
Any command using meta.defaultFlagSet *might* occasionally exit before
the flag package's output got written. This caused flag error messages
to get lost. This PR discards the flag package output in favor of
directly returning the error to the end user.
Previously we were doing this rather inconsistently: some commands would
do it and others would not. By doing it here we ensure we always apply the
same normalization, regardless of which operation we're running.
This normalization is mostly for cosmetic purposes in error messages, but
it also ends up being used to populate path.module and path.root and so
it's important that we always produce consistent results here so that
we don't produce flappy changes as users work with different commands.
The fact that thus mutates a data structure as a side-effect is not ideal
but this is the best place to ensure it always gets applied without doing
any significant refactoring, since everything after this point happens in
the backend package where the normalizePath method is not available.
A lot of commands used `c.Meta.flagSet()` to create the initial flagset for the command, while quite a few of them didn’t actually use or support the flags that are then added.
So I updated a few commands to use `flag.NewFlagSet()` instead to only add the flags that are actually needed/supported.
Additionally this prevents a few commands from using locking while they actually don’t need locking (as locking is enabled as a default in `c.Meta.flagSet()`.
The mission of this process method used to include dealing with
auto-loaded tfvars files, but it doesn't do that anymore.
It does still deal with the -no-color option, but the test wasn't
exercising that part before.
Now the test here focuses on the -no-color behavior.
The process method still has a "vars" flag argument which is no longer
used. Since this is an unexported method we could potentially address this
but this commit is intentionally limited only to fixing the test.
This work was done against APIs that were already changed in the branch
before work began, and so it doesn't apply to the v0.12 development work.
To allow v0.12 to merge down to master, we'll revert this work out for now
and then re-introduce equivalent functionality in later commits that works
against the new APIs.
Due to how often the state and plan types are referenced throughout
Terraform, there isn't a great way to switch them out gradually. As a
consequence, this huge commit gets us from the old world to a _compilable_
new world, but still has a large number of known test failures due to
key functionality being stubbed out.
The stubs here are for anything that interacts with providers, since we
now need to do the follow-up work to similarly replace the old
terraform.ResourceProvider interface with its replacement in the new
"providers" package. That work, along with work to fix the remaining
failing tests, will follow in subsequent commits.
The aim here was to replace all references to terraform.State and its
downstream types with states.State, terraform.Plan with plans.Plan,
state.State with statemgr.State, and switch to the new implementations of
the state and plan file formats. However, due to the number of times those
types are used, this also ended up affecting numerous other parts of core
such as terraform.Hook, the backend.Backend interface, and most of the CLI
commands.
Just as with 5861dbf3fc49b19587a31816eb06f511ab861bb4 before, I apologize
in advance to the person who inevitably just found this huge commit while
spelunking through the commit history.
Chris Arcand