terraform/internal/getproviders/legacy_lookup.go

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internal/getproviders: LookupLegacyProvider This is a temporary helper so that we can potentially ship the new provider installer without making a breaking change by relying on the old default namespace lookup API on the default registry to find a proper FQN for a legacy provider provider address during installation. If it's given a non-legacy provider address then it just returns the given address verbatim, so any codepath using it will also correctly handle explicit full provider addresses. This also means it will automatically self-disable once we stop using addrs.NewLegacyProvider in the config loader, because there will therefore no longer be any legacy provider addresses in the config to resolve. (They'll be "default" provider addresses instead, assumed to be under registry.terraform.io/hashicorp/* ) It's not decided yet whether we will actually introduce the new provider in a minor release, but even if we don't this API function will likely be useful for a hypothetical automatic upgrade tool to introduce explicit full provider addresses into existing modules that currently rely on the equivalent to this lookup in the current provider installer. This is dead code for now, but my intent is that it would either be called as part of new provider installation to produce an address suitable to pass to Source.AvailableVersions, or it would be called from the aforementioned hypothetical upgrade tool. Whatever happens, these functions can be removed no later than one whole major release after the new provider installer is introduced, when everyone's had the opportunity to update their legacy unqualified addresses.
2020-01-22 01:01:49 +01:00
package getproviders
import (
"fmt"
svchost "github.com/hashicorp/terraform-svchost"
"github.com/hashicorp/terraform/addrs"
)
// LookupLegacyProvider attempts to resolve a legacy provider address (whose
// registry host and namespace are implied, rather than explicit) into a
// fully-qualified provider address, by asking the main Terraform registry
// to resolve it.
//
// If the given address is not a legacy provider address then it will just be
// returned verbatim without making any outgoing requests.
//
// Legacy provider lookup is possible only if the given source is either a
// *RegistrySource directly or if it is a MultiSource containing a
// *RegistrySource whose selector matching patterns include the
// public registry hostname registry.terraform.io.
//
// This is a backward-compatibility mechanism for compatibility with existing
// configurations that don't include explicit provider source addresses. New
// configurations should not rely on it, and this fallback mechanism is
// likely to be removed altogether in a future Terraform version.
func LookupLegacyProvider(addr addrs.Provider, source Source) (addrs.Provider, error) {
if addr.Namespace != "-" {
return addr, nil
}
if addr.Hostname != defaultRegistryHost { // condition above assures namespace is also "-"
// Legacy providers must always belong to the default registry host.
return addrs.Provider{}, fmt.Errorf("invalid provider type %q: legacy provider addresses must always belong to %s", addr, defaultRegistryHost)
}
// Now we need to derive a suitable *RegistrySource from the given source,
// either directly or indirectly. This will not be possible if the user
// has configured Terraform to disable direct installation from
// registry.terraform.io; in that case, fully-qualified provider addresses
// are always required.
regSource := findLegacyProviderLookupSource(addr.Hostname, source)
if regSource == nil {
// This error message is assuming that the given Source was produced
// based on the CLI configuration, which isn't necessarily true but
// is true in all cases where this error message will ultimately be
// presented to an end-user, so good enough for now.
return addrs.Provider{}, fmt.Errorf("unqualified provider type %q cannot be resolved because direct installation from %s is disabled in the CLI configuration; declare an explicit provider namespace for this provider", addr.Type, addr.Hostname)
}
defaultNamespace, err := regSource.LookupLegacyProviderNamespace(addr.Hostname, addr.Type)
if err != nil {
return addrs.Provider{}, err
}
return addrs.Provider{
Hostname: addr.Hostname,
Namespace: defaultNamespace,
Type: addr.Type,
}, nil
}
// findLegacyProviderLookupSource tries to find a *RegistrySource that can talk
// to the given registry host in the given Source. It might be given directly,
// or it might be given indirectly via a MultiSource where the selector
// includes a wildcard for registry.terraform.io.
//
// Returns nil if the given source does not have any configured way to talk
// directly to the given host.
//
// If the given source contains multiple sources that can talk to the given
// host directly, the first one in the sequence takes preference. In practice
// it's pointless to have two direct installation sources that match the same
// hostname anyway, so this shouldn't arise in normal use.
func findLegacyProviderLookupSource(host svchost.Hostname, source Source) *RegistrySource {
switch source := source.(type) {
case *RegistrySource:
// Easy case: the source is a registry source directly, and so we'll
// just use it.
return source
case MultiSource:
// Trickier case: if it's a multisource then we need to scan over
// its selectors until we find one that is a *RegistrySource _and_
// that is configured to accept arbitrary providers from the
// given hostname.
// For our matching purposes we'll use an address that would not be
// valid as a real provider FQN and thus can only match a selector
// that has no filters at all or a selector that wildcards everything
// except the hostname, like "registry.terraform.io/*/*"
matchAddr := addrs.Provider{
Hostname: host,
// Other fields are intentionally left empty, to make this invalid
// as a specific provider address.
}
for _, selector := range source {
// If this source has suitable matching patterns to install from
// the given hostname then we'll recursively search inside it
// for *RegistrySource objects.
if selector.CanHandleProvider(matchAddr) {
ret := findLegacyProviderLookupSource(host, selector.Source)
if ret != nil {
return ret
}
}
}
// If we get here then there were no selectors that are both configured
// to handle modules from the given hostname and that are registry
// sources, so we fail.
return nil
default:
// This source cannot be and cannot contain a *RegistrySource, so
// we fail.
return nil
}
}