Add warning message for deprecated "hashicorp/terraform" provider

src/internal/warnings/warnings.go

@@ -0,0 +1,21 @@
+// Package warnings defines the warnings associated with the provider
+package warnings
+
+// ProviderWarnings return the list of warnings for a given provider identified by its namespace and type
+//
+// Example: registry.terraform.io/hashicorp/terraform
+//
+// warn := ProviderWarnings("hashicorp", "terraform")
+// fmt.Println(warn)
+// >> [This provider is archived and no longer needed. The terraform_remote_state data source is built into the latest OpenTofu release.]
+func ProviderWarnings(providerNamespace, providerType string) []string {
+	switch providerNamespace { //nolint:gocritic // Switch is more appropriate than 'if' for the use case
+	case "hashicorp":
+		switch providerType { //nolint:gocritic // Switch is more appropriate than 'if' for the use case
+		case "terraform":
+			return []string{`This provider is archived and no longer needed. The terraform_remote_state data source is built into the latest OpenTofu release.`}
+		}
+	}
+
+	return nil
+}

src/internal/warnings/warnings_test.go

@@ -0,0 +1,44 @@
+package warnings
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestProviderWarnings(t *testing.T) {
+	type args struct {
+		providerNamespace string
+		providerType      string
+	}
+	tests := []struct {
+		name string
+		args args
+		want []string
+	}{
+		{
+			name: "shall return no warnings",
+			args: args{
+				providerNamespace: "foo",
+				providerType:      "bar",
+			},
+			want: nil,
+		},
+		{
+			name: "shall return warnings as in https://github.com/opentofu/registry/issues/108",
+			args: args{
+				providerNamespace: "hashicorp",
+				providerType:      "terraform",
+			},
+			want: []string{`This provider is archived and no longer needed. The terraform_remote_state data source is built into the latest OpenTofu release.`},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(
+			tt.name, func(t *testing.T) {
+				if got := ProviderWarnings(tt.args.providerNamespace, tt.args.providerType); !reflect.DeepEqual(got, tt.want) {
+					t.Errorf("ProviderWarnings() = %v, want %v", got, tt.want)
+				}
+			},
+		)
+	}
+}

src/lambda/api/providerVersions.go

@@ -14,6 +14,7 @@ import (
 	"github.com/opentofu/registry/internal/github"
 	"github.com/opentofu/registry/internal/providers"
 	"github.com/opentofu/registry/internal/providers/types"
+	"github.com/opentofu/registry/internal/warnings"
 	"golang.org/x/exp/slog"
 )
 
@@ -39,6 +40,7 @@ func getListProvidersPathParams(req events.APIGatewayProxyRequest) ListProviders
 
 type ListProviderVersionsResponse struct {
 	Versions []types.Version `json:"versions"`
+	Warnings []string        `json:"warnings,omitempty"`
 }
 
 func listProviderVersions(config config.Config) LambdaFunc {
@@ -47,17 +49,18 @@ func listProviderVersions(config config.Config) LambdaFunc {
 		params.AnnotateLogger()
 
 		effectiveNamespace := config.EffectiveProviderNamespace(params.Namespace)
-		repoName := providers.GetRepoName(params.Type)
 
-		// For now, we will ignore errors from the cache and just fetch from GH instead if the document doesn't exist
-		document, _ := config.ProviderVersionCache.GetItem(ctx, fmt.Sprintf("%s/%s", effectiveNamespace, params.Type))
-		if document != nil {
-			return processDocumentForProviderListing(ctx, document, config, effectiveNamespace, params.Type)
+		// Warnings lookup: https://github.com/opentofu/registry/issues/108
+		warn := warnings.ProviderWarnings(params.Namespace, params.Type)
+
+		// For now, we will ignore errors from the cache and just fetch from GH instead
+		versionList, _ := listVersionsFromCache(ctx, config, effectiveNamespace, params.Type)
+		if len(versionList) > 0 {
+			return versionsResponse(versionList, warn)
 		}
 
-		// now that we know we don't have the document, we should check that the repo exists
-		// if we checked the repo exists before then we are making extra calls to GitHub that we don't need to make.
-		if exists, err := github.RepositoryExists(ctx, config.ManagedGithubClient, effectiveNamespace, repoName); !exists {
+		versionList, repoExists, err := listVersionsFromRepository(ctx, config, effectiveNamespace, params.Type)
+		if !repoExists {
 			if err != nil {
 				slog.Error("Error checking if repo exists", "error", err)
 				return events.APIGatewayProxyResponse{StatusCode: http.StatusInternalServerError}, err
@@ -66,43 +69,46 @@ func listProviderVersions(config config.Config) LambdaFunc {
 			// if the repo doesn't exist, there's no point in trying to fetch versions
 			return NotFoundResponse, nil
 		}
+		if err != nil {
+			slog.Error("Error fetching versions from github", "error", err)
+			return events.APIGatewayProxyResponse{StatusCode: http.StatusInternalServerError}, err
+		}
 
-		// if the document didn't exist in the cache, trigger the lambda to populate it and return the current results from GH
+		// if the document didn't exist in the cache, trigger the lambda to populate it
 		if err := triggerPopulateProviderVersions(ctx, config, effectiveNamespace, params.Type); err != nil {
 			slog.Error("Error triggering lambda", "error", err)
 		}
 
-		return fetchFromGithub(ctx, config, effectiveNamespace, repoName)
+		return versionsResponse(versionList, warn)
 	}
 }
 
-func processDocumentForProviderListing(ctx context.Context, document *types.CacheItem, config config.Config, namespace, providerType string) (events.APIGatewayProxyResponse, error) {
-	slog.Info("Found document in cache", "last_updated", document.LastUpdated, "versions", len(document.Versions))
-
-	if !document.IsStale() {
-		slog.Info("Document is not too old, returning cached versions", "last_updated", document.LastUpdated)
-		return versionsResponse(document.Versions.ToVersions())
+func listVersionsFromCache(ctx context.Context, config config.Config, effectiveNamespace, providerType string) ([]types.Version, error) {
+	document, err := config.ProviderVersionCache.GetItem(ctx, fmt.Sprintf("%s/%s", effectiveNamespace, providerType))
+	if err != nil || document == nil {
+		return nil, err
 	}
 
-	slog.Info("Document is too old, triggering lambda to update dynamodb", "last_updated", document.LastUpdated)
-	if err := triggerPopulateProviderVersions(ctx, config, namespace, providerType); err != nil {
-		// if we can't trigger the lambda, we should still return the cached versions and just log the error
-		slog.Error("Error triggering lambda", "error", err)
+	slog.Info("Found document in cache", "last_updated", document.LastUpdated, "versions", len(document.Versions))
+
+	if document.IsStale() {
+		return nil, nil
 	}
 
-	return versionsResponse(document.Versions.ToVersions())
+	slog.Info("Document is not too old, returning cached versions", "last_updated", document.LastUpdated)
+	return document.Versions.ToVersions(), nil
 }
 
-func fetchFromGithub(ctx context.Context, config config.Config, namespace, repoName string) (events.APIGatewayProxyResponse, error) {
-	slog.Info("Fetching versions from github\n")
-
-	versionList, err := providers.GetVersions(ctx, config.RawGithubv4Client, namespace, repoName)
+func listVersionsFromRepository(ctx context.Context, config config.Config, effectiveNamespace, providerType string) ([]types.Version, bool, error) {
+	repoName := providers.GetRepoName(providerType)
+	exists, err := github.RepositoryExists(ctx, config.ManagedGithubClient, effectiveNamespace, repoName)
 	if err != nil {
-		slog.Error("Error fetching versions from github", "error", err)
-		return events.APIGatewayProxyResponse{StatusCode: http.StatusInternalServerError}, err
+		return nil, exists, err
 	}
 
-	return versionsResponse(versionList.ToVersions())
+	slog.Info("Fetching versions from github\n")
+	versionList, err := providers.GetVersions(ctx, config.RawGithubv4Client, effectiveNamespace, repoName)
+	return versionList.ToVersions(), exists, err
 }
 
 func triggerPopulateProviderVersions(ctx context.Context, config config.Config, effectiveNamespace string, effectiveType string) error {
@@ -120,11 +126,15 @@ func triggerPopulateProviderVersions(ctx context.Context, config config.Config,
 	return nil
 }
 
-func versionsResponse(versions []types.Version) (events.APIGatewayProxyResponse, error) {
+func versionsResponse(versions []types.Version, warnings []string) (events.APIGatewayProxyResponse, error) {
 	response := ListProviderVersionsResponse{
 		Versions: versions,
 	}
 
+	if len(warnings) > 0 {
+		response.Warnings = warnings
+	}
+
 	resBody, err := json.Marshal(response)
 	if err != nil {
 		return events.APIGatewayProxyResponse{StatusCode: http.StatusInternalServerError}, err