terraform/terraform/eval_state_upgrade.go

116 lines
4.8 KiB
Go

package terraform
import (
"fmt"
"log"
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/terraform/configs/configschema"
"github.com/hashicorp/terraform/providers"
"github.com/hashicorp/terraform/states"
"github.com/hashicorp/terraform/tfdiags"
)
// UpgradeResourceState will, if necessary, run the provider-defined upgrade
// logic against the given state object to make it compliant with the
// current schema version. This is a no-op if the given state object is
// already at the latest version.
//
// If any errors occur during upgrade, error diagnostics are returned. In that
// case it is not safe to proceed with using the original state object.
func UpgradeResourceState(addr addrs.AbsResourceInstance, provider providers.Interface, src *states.ResourceInstanceObjectSrc, currentSchema *configschema.Block, currentVersion uint64) (*states.ResourceInstanceObjectSrc, tfdiags.Diagnostics) {
currentTy := currentSchema.ImpliedType()
// If the state is currently in flatmap format and the current schema
// contains DynamicPseudoType attributes then we won't be able to convert
// it to JSON without the provider's help even if the schema version matches,
// since only the provider knows how to interpret the dynamic attribute
// value in flatmap format to convert it to JSON.
schemaHasDynamic := currentTy.HasDynamicTypes()
stateIsFlatmap := len(src.AttrsJSON) == 0
forceProviderUpgrade := schemaHasDynamic && stateIsFlatmap
if src.SchemaVersion == currentVersion && !forceProviderUpgrade {
// No upgrading required, then.
return src, nil
}
if addr.Resource.Resource.Mode != addrs.ManagedResourceMode {
// We only do state upgrading for managed resources.
return src, nil
}
providerType := addr.Resource.Resource.DefaultProviderConfig().Type
if src.SchemaVersion > currentVersion {
log.Printf("[TRACE] UpgradeResourceState: can't downgrade state for %s from version %d to %d", addr, src.SchemaVersion, currentVersion)
var diags tfdiags.Diagnostics
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Resource instance managed by newer provider version",
// This is not a very good error message, but we don't retain enough
// information in state to give good feedback on what provider
// version might be required here. :(
fmt.Sprintf("The current state of %s was created by a newer provider version than is currently selected. Upgrade the %s provider to work with this state.", addr, providerType),
))
return nil, diags
}
// If we get down here then we need to upgrade the state, with the
// provider's help.
// If this state was originally created by a version of Terraform prior to
// v0.12, this also includes translating from legacy flatmap to new-style
// representation, since only the provider has enough information to
// understand a flatmap built against an older schema.
log.Printf("[TRACE] UpgradeResourceState: upgrading state for %s from version %d to %d using provider %q", addr, src.SchemaVersion, currentVersion, providerType)
req := providers.UpgradeResourceStateRequest{
TypeName: addr.Resource.Resource.Type,
// TODO: The internal schema version representations are all using
// uint64 instead of int64, but unsigned integers aren't friendly
// to all protobuf target languages so in practice we use int64
// on the wire. In future we will change all of our internal
// representations to int64 too.
Version: int64(src.SchemaVersion),
}
if stateIsFlatmap {
req.RawStateFlatmap = src.AttrsFlat
} else {
req.RawStateJSON = src.AttrsJSON
}
resp := provider.UpgradeResourceState(req)
diags := resp.Diagnostics
if diags.HasErrors() {
return nil, diags
}
// After upgrading, the new value must conform to the current schema. When
// going over RPC this is actually already ensured by the
// marshaling/unmarshaling of the new value, but we'll check it here
// anyway for robustness, e.g. for in-process providers.
newValue := resp.UpgradedState
if errs := newValue.Type().TestConformance(currentSchema.ImpliedType()); len(errs) > 0 {
for _, err := range errs {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Invalid resource state upgrade",
fmt.Sprintf("The %s provider upgraded the state for %s from a previous version, but produced an invalid result: %s.", providerType, addr, tfdiags.FormatError(err)),
))
}
return nil, diags
}
new, err := src.CompleteUpgrade(newValue, currentSchema.ImpliedType(), uint64(currentVersion))
if err != nil {
// We already checked for type conformance above, so getting into this
// codepath should be rare and is probably a bug somewhere under CompleteUpgrade.
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Failed to encode result of resource state upgrade",
fmt.Sprintf("Failed to encode state for %s after resource schema upgrade: %s.", addr, tfdiags.FormatError(err)),
))
}
return new, diags
}