We have these funny extra options that date back to before Terraform even
had remote state, which we've preserved along the way by most recently
incorporating them as special-case overrides for the local backend.
The documentation we had for these has grown less accurate over time as
the details have shifted, and was in many cases missing the requisite
caveats that they are only for the local backend and that backend
configuration is the modern, preferred way to deal with the use-cases they
were intended for.
We always have a bit of a tension with this sort of legacy option because
we want to keep them documented just enough to be useful to someone who
finds an existing script/etc using them and wants to know what they do,
but not to take up so much space that they might distract users from
finding the modern alternative they should consider instead.
As a compromise in that vein here I've created a new section about these
options under the local backend documentation, which then gives us the
space to go into some detail about the various behaviors and interactions
and also to discuss their history and our recommended alternatives. I then
simplified all of the other mentions of these in command documentation
to just link to or refer to the local backend documentation. My hope then
is that folks who need to know what these do can still find the docs, but
that information can be kept out of the direct path of new users so they
can focus on learning about remote backends instead.
This is certainly not the most ideal thing ever, but it seemed like the
best compromise between the competing priorities I described above.
The previous implementation of views was copying and embedding the base
View struct in each individual view. While this allowed for easy access
to the interface of that struct (both in the view and externally), it more
importantly completely broke the ability of the diagnostic printer to
output source code snippets.
This is because the `configSources` field on the base view is lazily set
after the config loader is initialized. In the commands ported to use
views, this happens after the base View struct is copied, so we are
updating the wrong copy of the struct.
This commit fixes this with a simple mechanical refactor: keep a pointer
to the base View struct instead, and update all of the individual views
to explicitly refer to that struct to access its fields and methods.
This is not a particularly satisfying solution, but I can't find
anything clearly better. It might be worth exploring the alternative
approach in the view for the new test command, which explicitly pulls
its dependencies out of the base view, rather than retaining a full
reference. Maybe there's a third way which is better still.
This commit extracts the remaining UI logic from the local backend,
and removes access to the direct CLI output. This is replaced with an
instance of a `views.Operation` interface, which codifies the current
requirements for the local backend to interact with the user.
The exception to this at present is interactivity: approving a plan
still depends on the `UIIn` field for the backend. This is out of scope
for this commit and can be revisited separately, at which time the
`UIOut` field can also be removed.
Changes in support of this:
- Some instances of direct error output have been replaced with
diagnostics, most notably in the emergency state backup handler. This
requires reformatting the error messages to allow the diagnostic
renderer to line-wrap them;
- The "in-automation" logic has moved out of the backend and into the
view implementation;
- The plan, apply, refresh, and import commands instantiate a view and
set it on the `backend.Operation` struct, as these are the only code
paths which call the `local.Operation()` method that requires it;
- The show command requires the plan rendering code which is now in the
views package, so there is a stub implementation of a `views.Show`
interface there.
Other refactoring work in support of migrating these commands to the
common views code structure will come in follow-up PRs, at which point
we will be able to remove the UI instances from the unit tests for those
commands.
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.
The enhanced backends (local and remote) need to be able to render
diagnostics during operations. Prior to this commit, this functionality
was supported with a per-backend `ShowDiagnostics` function pointer.
In order to allow users of these backends to control how diagnostics are
rendered, this commit moves that function pointer to the `Operation`
type. This means that a diagnostic renderer is configured for each
operation, rather than once per backend initialization.
Some secondary consequences of this change:
- The `ReportResult` method on the backend is now moved to the
`Operation` type, as it needs to access the `ShowDiagnostics` callback
(and nothing else from the backend);
- Tests which assumed that diagnostics would be written to the backend's
`cli.Ui` instance are migrated to using a new record/playback diags
helper function;
- Apply, plan, and refresh commands now pass a pointer to the `Meta`
struct's `showDiagnostics` method.
This commit should not change how Terraform works, and is refactoring in
preparation for more changes which move UI code out of the backend.
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.
Several commands continued to support the legacy positional path
argument to specify a working directory. This functionality has been
replaced with the global -chdir flag, which is specified before any
other arguments, including the sub-command name.
This commit removes support for the trailing path parameter from
most commands. The only command which still supports a path argument is
fmt, which also supports "-" to indicate receiving configuration from
standard input.
Any invocation of a command with an invalid trailing path parameter will
result in a short error message, pointing at the -chdir alternative.
There are many test updates in this commit, almost all of which are
migrations from using positional arguments to specify a working
directory. Because of the layer at which these tests run, we are unable
to use the -chdir argument, so the churn in test files is larger than
ideal. Sorry!
The -module flag to terraform output has been unimplemented since 0.12.
This commit removes some dead code and the specific error message for
this flag.
The website documentation for output does not mention this flag, so it
is unchanged.
The short description of our commands (as shown in the main help output
from "terraform") was previously very inconsistent, using different
tense/mood for different commands. Some of the commands were also using
some terminology choices inconsistent with how we currently talk about
the related ideas in our documentation.
Here I've tried to add some consistency by first rewriting them all in
the imperative mood (except the ones that just are just subcommand
groupings), and tweaking some of the terminology to hopefully gel better
with how we present similar ideas in our recently-updated docs.
While working on this I inevitably spotted some similar inconsistencies
in the longer-form help output of some of the commands. I've not reviewed
all of these for consistency, but I did update some where the wording
was either left inconsstent with the short form changes I'd made or
where the prose stood out to me as particularly inconsistent with our
current usual documentation language style.
All of this is subjective, so I expect we'll continue to tweak these over
time as we continue to develop our documentation writing style based on
user questions and feedback.
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.
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()`.
This connects a missing link left by earlier refactoring: the command
package is responsible for gathering up variable values provided by the
user and passing them through to the backend to use in operations.
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.
This is a rather-messy, complex change to get the "command" package
building again against the new backend API that was updated for
the new configuration loader.
A lot of this is mechanical rewriting to the new API, but
meta_config.go and meta_backend.go in particular saw some major
changes to interface with the new loader APIs and to deal with
the change in order of steps in the backend API.
If the user wishes to interrupt the running operation, only the first
interrupt was communicated to the operation by canceling the provided
context. A second interrupt would start the shutdown process, but not
communicate this to the running operation. This order of event could
cause partial writes of state.
What would happen is that once the command returns, the plugin system
would stop the provider processes. Once the provider processes dies, all
pending Eval operations would return return with an error, and quickly
cause the operation to complete. Since the backend code didn't know that
the process was shutting down imminently, it would continue by
attempting to write out the last known state. Under the right
conditions, the process would exit part way through the writing of the
state file.
Add Stop and Cancel CancelFuncs to the RunningOperation, to allow it to
easily differentiate between the two signals. The backend will then be
able to detect a shutdown and abort more gracefully.
In order to ensure that the backend is not in the process of writing the
state out, the command will always attempt to wait for the process to
complete after cancellation.
Previously we required callers to separately call .Validate on the root
module to determine if there were any value errors, but we did that
inconsistently and would thus see crashes in some cases where later code
would try to use invalid configuration as if it were valid.
Now we run .Validate automatically after config loading, returning the
resulting diagnostics. Since we return a diagnostics here, it's possible
to return both warnings and errors.
We return the loaded module even if it's invalid, so callers are free to
ignore returned errors and try to work with the config anyway, though they
will need to be defensive against invalid configuration themselves in
that case.
As a result of this, all of the commands that load configuration now need
to use diagnostic printing to signal errors. For the moment this just
allows us to return potentially-multiple config errors/warnings in full
fidelity, but also sets us up for later when more subsystems are able
to produce rich diagnostics so we can show them all together.
Finally, this commit also removes some stale, commented-out code for the
"legacy" (pre-0.8) graph implementation, which has not been available
for some time.
This uses the new diagnostics printer for config-related errors in the
main five commands that deal with config.
The immediate motivation for this is to allow HCL2-produced diagnostics
to be printed out in their full fidelity, though it also slightly changes
the presentation of other errors so that they are not presented in all
red text, which can be hard to read on some terminals.
Instead of providing the a path in BackendOpts, provide a loaded
*config.Config instead. This reduces the number of places where
configuration is loaded.
Add the -lock-timeout flag to the appropriate commands.
Add the -lock flag to `init` and `import` which were missing it.
Set both stateLock and stateLockTimeout in Meta.flagsSet, and remove the
extra references for clarity.
The behaviour whereby outputs for a particular nested module can be
output was broken by the changes for lists and maps. This commit
restores the previous behaviour by passing the module path into the
outputsAsString function.
We also add a new test of this since the code path for indivdual output
vs all outputs for a module has diverged.
- Fix sensitive outputs for lists and maps
- Fix test prelude which was missed during conflict resolution
- Fix `terraform output` to match old behaviour and not have outputs
header and colouring
- Bump timeout on TestAtlasClient_UnresolvableConflict
* core: Add support for marking outputs as sensitive
This commit allows an output to be marked "sensitive", in which case the
value is redacted in the post-refresh and post-apply list of outputs.
For example, the configuration:
```
variable "input" {
default = "Hello world"
}
output "notsensitive" {
value = "${var.input}"
}
output "sensitive" {
sensitive = true
value = "${var.input}"
}
```
Would result in the output:
```
terraform apply
Apply complete! Resources: 0 added, 0 changed, 0 destroyed.
Outputs:
notsensitive = Hello world
sensitive = <sensitive>
```
The `terraform output` command continues to display the value as before.
Limitations: Note that sensitivity is not tracked internally, so if the
output is interpolated in another module into a resource, the value will
be displayed. The value is still present in the state.
Add `-target=resource` flag to core operations, allowing users to
target specific resources in their infrastructure. When `-target` is
used, the operation will only apply to that resource and its
dependencies.
The calculated dependencies are different depending on whether we're
running a normal operation or a `terraform destroy`.
Generally, "dependencies" refers to ancestors: resources falling
_before_ the target in the graph, because their changes are required to
accurately act on the target.
For destroys, "dependencies" are descendents: those resources which fall
_after_ the target. These resources depend on our target, which is going
to be destroyed, so they should also be destroyed.
Martin Atkins