opentofu/internal/backend/remote/backend_context_test.go
Martin Atkins 89b05050ec core: Functional-style API for terraform.Context
Previously terraform.Context was built in an unfortunate way where all of
the data was provided up front in terraform.NewContext and then mutated
directly by subsequent operations. That made the data flow hard to follow,
commonly leading to bugs, and also meant that we were forced to take
various actions too early in terraform.NewContext, rather than waiting
until a more appropriate time during an operation.

This (enormous) commit changes terraform.Context so that its fields are
broadly just unchanging data about the execution context (current
workspace name, available plugins, etc) whereas the main data Terraform
works with arrives via individual method arguments and is returned in
return values.

Specifically, this means that terraform.Context no longer "has-a" config,
state, and "planned changes", instead holding on to those only temporarily
during an operation. The caller is responsible for propagating the outcome
of one step into the next step so that the data flow between operations is
actually visible.

However, since that's a change to the main entry points in the "terraform"
package, this commit also touches every file in the codebase which
interacted with those APIs. Most of the noise here is in updating tests
to take the same actions using the new API style, but this also affects
the main-code callers in the backends and in the command package.

My goal here was to refactor without changing observable behavior, but in
practice there are a couple externally-visible behavior variations here
that seemed okay in service of the broader goal:
 - The "terraform graph" command is no longer hooked directly into the
   core graph builders, because that's no longer part of the public API.
   However, I did include a couple new Context functions whose contract
   is to produce a UI-oriented graph, and _for now_ those continue to
   return the physical graph we use for those operations. There's no
   exported API for generating the "validate" and "eval" graphs, because
   neither is particularly interesting in its own right, and so
   "terraform graph" no longer supports those graph types.
 - terraform.NewContext no longer has the responsibility for collecting
   all of the provider schemas up front. Instead, we wait until we need
   them. However, that means that some of our error messages now have a
   slightly different shape due to unwinding through a differently-shaped
   call stack. As of this commit we also end up reloading the schemas
   multiple times in some cases, which is functionally acceptable but
   likely represents a performance regression. I intend to rework this to
   use caching, but I'm saving that for a later commit because this one is
   big enough already.

The proximal reason for this change is to resolve the chicken/egg problem
whereby there was previously no single point where we could apply "moved"
statements to the previous run state before creating a plan. With this
change in place, we can now do that as part of Context.Plan, prior to
forking the input state into the three separate state artifacts we use
during planning.

However, this is at least the third project in a row where the previous
API design led to piling more functionality into terraform.NewContext and
then working around the incorrect order of operations that produces, so
I intend that by paying the cost/risk of this large diff now we can in
turn reduce the cost/risk of future projects that relate to our main
workflow actions.
2021-08-30 13:59:14 -07:00

236 lines
6.7 KiB
Go

package remote
import (
"context"
"testing"
tfe "github.com/hashicorp/go-tfe"
"github.com/hashicorp/terraform/internal/backend"
"github.com/hashicorp/terraform/internal/command/arguments"
"github.com/hashicorp/terraform/internal/command/clistate"
"github.com/hashicorp/terraform/internal/command/views"
"github.com/hashicorp/terraform/internal/configs"
"github.com/hashicorp/terraform/internal/initwd"
"github.com/hashicorp/terraform/internal/states/statemgr"
"github.com/hashicorp/terraform/internal/terminal"
"github.com/zclconf/go-cty/cty"
)
func TestRemoteStoredVariableValue(t *testing.T) {
tests := map[string]struct {
Def *tfe.Variable
Want cty.Value
WantError string
}{
"string literal": {
&tfe.Variable{
Key: "test",
Value: "foo",
HCL: false,
Sensitive: false,
},
cty.StringVal("foo"),
``,
},
"string HCL": {
&tfe.Variable{
Key: "test",
Value: `"foo"`,
HCL: true,
Sensitive: false,
},
cty.StringVal("foo"),
``,
},
"list HCL": {
&tfe.Variable{
Key: "test",
Value: `[]`,
HCL: true,
Sensitive: false,
},
cty.EmptyTupleVal,
``,
},
"null HCL": {
&tfe.Variable{
Key: "test",
Value: `null`,
HCL: true,
Sensitive: false,
},
cty.NullVal(cty.DynamicPseudoType),
``,
},
"literal sensitive": {
&tfe.Variable{
Key: "test",
HCL: false,
Sensitive: true,
},
cty.UnknownVal(cty.String),
``,
},
"HCL sensitive": {
&tfe.Variable{
Key: "test",
HCL: true,
Sensitive: true,
},
cty.DynamicVal,
``,
},
"HCL computation": {
// This (stored expressions containing computation) is not a case
// we intentionally supported, but it became possible for remote
// operations in Terraform 0.12 (due to Terraform Cloud/Enterprise
// just writing the HCL verbatim into generated `.tfvars` files).
// We support it here for consistency, and we continue to support
// it in both places for backward-compatibility. In practice,
// there's little reason to do computation in a stored variable
// value because references are not supported.
&tfe.Variable{
Key: "test",
Value: `[for v in ["a"] : v]`,
HCL: true,
Sensitive: false,
},
cty.TupleVal([]cty.Value{cty.StringVal("a")}),
``,
},
"HCL syntax error": {
&tfe.Variable{
Key: "test",
Value: `[`,
HCL: true,
Sensitive: false,
},
cty.DynamicVal,
`Invalid expression for var.test: The value of variable "test" is marked in the remote workspace as being specified in HCL syntax, but the given value is not valid HCL. Stored variable values must be valid literal expressions and may not contain references to other variables or calls to functions.`,
},
"HCL with references": {
&tfe.Variable{
Key: "test",
Value: `foo.bar`,
HCL: true,
Sensitive: false,
},
cty.DynamicVal,
`Invalid expression for var.test: The value of variable "test" is marked in the remote workspace as being specified in HCL syntax, but the given value is not valid HCL. Stored variable values must be valid literal expressions and may not contain references to other variables or calls to functions.`,
},
}
for name, test := range tests {
t.Run(name, func(t *testing.T) {
v := &remoteStoredVariableValue{
definition: test.Def,
}
// This ParseVariableValue implementation ignores the parsing mode,
// so we'll just always parse literal here. (The parsing mode is
// selected by the remote server, not by our local configuration.)
gotIV, diags := v.ParseVariableValue(configs.VariableParseLiteral)
if test.WantError != "" {
if !diags.HasErrors() {
t.Fatalf("missing expected error\ngot: <no error>\nwant: %s", test.WantError)
}
errStr := diags.Err().Error()
if errStr != test.WantError {
t.Fatalf("wrong error\ngot: %s\nwant: %s", errStr, test.WantError)
}
} else {
if diags.HasErrors() {
t.Fatalf("unexpected error\ngot: %s\nwant: <no error>", diags.Err().Error())
}
got := gotIV.Value
if !test.Want.RawEquals(got) {
t.Errorf("wrong result\ngot: %#v\nwant: %#v", got, test.Want)
}
}
})
}
}
func TestRemoteContextWithVars(t *testing.T) {
catTerraform := tfe.CategoryTerraform
catEnv := tfe.CategoryEnv
tests := map[string]struct {
Opts *tfe.VariableCreateOptions
WantError string
}{
"Terraform variable": {
&tfe.VariableCreateOptions{
Category: &catTerraform,
},
`Value for undeclared variable: A variable named "key" was assigned a value, but the root module does not declare a variable of that name. To use this value, add a "variable" block to the configuration.`,
},
"environment variable": {
&tfe.VariableCreateOptions{
Category: &catEnv,
},
``,
},
}
for name, test := range tests {
t.Run(name, func(t *testing.T) {
configDir := "./testdata/empty"
b, bCleanup := testBackendDefault(t)
defer bCleanup()
_, configLoader, configCleanup := initwd.MustLoadConfigForTests(t, configDir)
defer configCleanup()
workspaceID, err := b.getRemoteWorkspaceID(context.Background(), backend.DefaultStateName)
if err != nil {
t.Fatal(err)
}
streams, _ := terminal.StreamsForTesting(t)
view := views.NewStateLocker(arguments.ViewHuman, views.NewView(streams))
op := &backend.Operation{
ConfigDir: configDir,
ConfigLoader: configLoader,
StateLocker: clistate.NewLocker(0, view),
Workspace: backend.DefaultStateName,
}
v := test.Opts
if v.Key == nil {
key := "key"
v.Key = &key
}
b.client.Variables.Create(context.TODO(), workspaceID, *v)
_, _, diags := b.LocalRun(op)
if test.WantError != "" {
if !diags.HasErrors() {
t.Fatalf("missing expected error\ngot: <no error>\nwant: %s", test.WantError)
}
errStr := diags.Err().Error()
if errStr != test.WantError {
t.Fatalf("wrong error\ngot: %s\nwant: %s", errStr, test.WantError)
}
// When Context() returns an error, it should unlock the state,
// so re-locking it is expected to succeed.
stateMgr, _ := b.StateMgr(backend.DefaultStateName)
if _, err := stateMgr.Lock(statemgr.NewLockInfo()); err != nil {
t.Fatalf("unexpected error locking state: %s", err.Error())
}
} else {
if diags.HasErrors() {
t.Fatalf("unexpected error\ngot: %s\nwant: <no error>", diags.Err().Error())
}
// When Context() succeeds, this should fail w/ "workspace already locked"
stateMgr, _ := b.StateMgr(backend.DefaultStateName)
if _, err := stateMgr.Lock(statemgr.NewLockInfo()); err == nil {
t.Fatal("unexpected success locking state after Context")
}
}
})
}
}