Custom State Checks

The package statecheck also provides the StateCheck interface, which can be implemented for a custom state check.

The statecheck.CheckStateRequest contains the current state file, parsed by the terraform-json package.

Here is an example implementation of a state check that asserts that a specific resource attribute has a known type and value:

package example_testimport (    "context"    "fmt"    tfjson "github.com/hashicorp/terraform-json"    "github.com/hashicorp/terraform-plugin-testing/knownvalue"    "github.com/hashicorp/terraform-plugin-testing/statecheck"    "github.com/hashicorp/terraform-plugin-testing/tfjsonpath")var _ statecheck.StateCheck = expectKnownValue{}type expectKnownValue struct {    resourceAddress string    attributePath   tfjsonpath.Path    knownValue      knownvalue.Check}func (e expectKnownValue) CheckState(ctx context.Context, req statecheck.CheckStateRequest, resp *statecheck.CheckStateResponse) {    var resource *tfjson.StateResource    if req.State == nil {        resp.Error = fmt.Errorf("state is nil")    }    if req.State.Values == nil {        resp.Error = fmt.Errorf("state does not contain any state values")    }    if req.State.Values.RootModule == nil {        resp.Error = fmt.Errorf("state does not contain a root module")    }    for _, r := range req.State.Values.RootModule.Resources {        if e.resourceAddress == r.Address {            resource = r            break        }    }    if resource == nil {        resp.Error = fmt.Errorf("%s - Resource not found in state", e.resourceAddress)        return    }    result, err := tfjsonpath.Traverse(resource.AttributeValues, e.attributePath)    if err != nil {        resp.Error = err        return    }    if err := e.knownValue.CheckValue(result); err != nil {        resp.Error = err    }}func ExpectKnownValue(resourceAddress string, attributePath tfjsonpath.Path, knownValue knownvalue.Check) statecheck.StateCheck {    return expectKnownValue{        resourceAddress: resourceAddress,        attributePath:   attributePath,        knownValue:      knownValue,    }}

And example usage:

package example_testimport (    "testing"    "github.com/hashicorp/terraform-plugin-testing/helper/resource"    "github.com/hashicorp/terraform-plugin-testing/knownvalue"    "github.com/hashicorp/terraform-plugin-testing/statecheck"    "github.com/hashicorp/terraform-plugin-testing/tfjsonpath")func TestExpectKnownValue_CheckState_Bool(t *testing.T) {    t.Parallel()    resource.Test(t, resource.TestCase{        // Provider definition omitted.        Steps: []resource.TestStep{            {                // Example resource containing a computed boolean attribute named "computed_attribute"                Config: `resource "test_resource" "one" {}`,                ConfigStateChecks: []statecheck.StateCheck{                    statecheck.ExpectKnownValue(                        "test_resource.one",                        tfjsonpath.New("computed_attribute"),                        knownvalue.Bool(true),                    ),                },            },        },    })}