So far the output command has had a default output format intended for
human consumption and a JSON output format intended for machine
consumption.
However, until Terraform v0.14 the default output format for primitive
types happened to be _almost_ a raw string representation of the value,
and so users started using that as a more convenient way to access
primitive-typed output values from shell scripts, avoiding the need to
also use a tool like "jq" to decode the JSON.
Recognizing that primitive-typed output values are common and that
processing them with shell scripts is common, this commit introduces a new
-raw mode which is explicitly intended for that use-case, guaranteeing
that the result will always be the direct result of a string conversion
of the output value, or an error if no such conversion is possible.
Our policy elsewhere in Terraform is that we always use JSON for
machine-readable output. We adopted that policy because our other
machine-readable output has typically been complex data structures rather
than single primitive values. A special mode seems justified for output
values because it is common for root module output values to be just
strings, and so it's pragmatic to offer access to the raw value directly
rather than requiring a round-trip through JSON.
Use a slightly modified value renderer from terraform-provider-testing
to display values in the console REPL, as well as outputs from the apply
and outputs subcommands.
Derived from code in this repository, MIT licensed:
https://github.com/apparentlymart/terraform-provider-testing
Note that this is technically a breaking change for the console
subcommand, which would previously error if the user attempted to render
an unknown value (such as an unset variable). This was marked as an
unintentional side effect, with the goal being the new behaviour of
rendering "(unknown)", which is why I changed the behaviour in this
commit.
When the output subcommand is called with no arguments, and there are no
outputs to show, we previously rendered an error message but returned a
non-error status code. This is confusing.
This commit changes the text UI to use a warning diagnostic, which makes
it clearer that this is a non-error situation. We do not change the exit
code or the text of the warning, so hopefully this is not considered a
breaking change.
We previously stubbed most of this out because it hadn't yet been updated
to support the new state types, etc.
This restores all of the previous behavior as covered by the tests.
We intentionally remove one behavior that was not covered by the tests:
we used to allow retrieval of outputs from non-root modules using the
-module option, but since we no longer persist non-root outputs in the
state we can no longer support this without a full expression evaluation
walk, and that'd be overkill for this otherwise-simple command. Descendant
module outputs are not part of the public interface of a configuration
anyway, so accessing them from outside in this way is an anti-pattern.
(For debugging scenarios it is still possible to access these from
"terraform console", which _does_ do a full evaluation graph walk to
prepare its evaluation scope.)
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.
- Fixes#11696
- This changes makes `terraform output -json` return '{}' instead of
throwing an error about "no outputs defined"
- If `-json` is not set, the user will receive an error as before
- This UX helps new users to understand how outputs are used
- Allows for easier automation of TF CLI as an empty set of outputs is
usually acceptable, but any other error from `output` would be
re-raised to the user.
Rather than try to modify all the hundreds of calls to the temp helper
functions, and cleanup the temp files at every call site, have all tests
work within a single temp directory that is removed at the end of
TestMain.
Previously we did plugin discovery in the main package, but as we move
towards versioned plugins we need more information available in order to
resolve plugins, so we move this responsibility into the command package
itself.
For the moment this is just preserving the existing behavior as long as
there are only internal and unversioned plugins present. This is the
final state for provisioners in 0.10, since we don't want to support
versioned provisioners yet. For providers this is just a checkpoint along
the way, since further work is required to apply version constraints from
configuration and support additional plugin search directories.
The automatic plugin discovery behavior is not desirable for tests because
we want to mock the plugins there, so we add a new backdoor for the tests
to use to skip the plugin discovery and just provide their own mock
implementations. Most of this diff is thus noisy rework of the tests to
use this new mechanism.
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.
This commit removes the ability to index into complex output types using
`terraform output a_list 1` (for example), and adds a `-json` flag to
the `terraform output` command, such that the output can be piped
through a post-processor such as jq or json. This removes the need to
allow arbitrary traversal of nested structures.
It also adds tests of human readable ("normal") output with nested lists
and maps, and of the new JSON output.
This commit forward ports the changes made for 0.6.17, in order to store
the type and sensitive flag against outputs.
It also refactors the logic of the import for V0 to V1 state, and
fixes up the call sites of the new format for outputs in V2 state.
Finally we fix up tests which did not previously set a state version
where one is required.
This commit adds the groundwork for supporting module outputs of types
other than string. In order to do so, the state version is increased
from 1 to 2 (though the "public-facing" state version is actually as the
first state file was binary).
Tests are added to ensure that V2 (1) state is upgraded to V3 (2) state,
though no separate read path is required since the V2 JSON will
unmarshal correctly into the V3 structure.
Outputs in a ModuleState are now of type map[string]interface{}, and a
test covers round-tripping string, []string and map[string]string, which
should cover all of the types in question.
Type switches have been added where necessary to deal with the
interface{} value, but they currently default to panicking when the input
is not a string.
Martin Atkins