Fix azure loader issues (#1682)

Fixes #1681

For providers such as Azure Classic that have a discrepancy between
"azure" and "azurerm", PULUMI_CONVERT=1 conversion no longer attempts to
resolve and download the "azurerm" plugin from GitHub.

pkg/tfgen/convert_cli.go

@@ -35,6 +35,7 @@ import (
 	hcl2nodejs "github.com/pulumi/pulumi/pkg/v3/codegen/nodejs"
 	"github.com/pulumi/pulumi/pkg/v3/codegen/pcl"
 	hcl2python "github.com/pulumi/pulumi/pkg/v3/codegen/python"
+	"github.com/pulumi/pulumi/pkg/v3/codegen/schema"
 	pschema "github.com/pulumi/pulumi/pkg/v3/codegen/schema"
 	"github.com/pulumi/pulumi/sdk/v3/go/common/resource/plugin"
 	"github.com/pulumi/pulumi/sdk/v3/go/common/util/cmdutil"
@@ -76,6 +77,8 @@ type cliConverter struct {
 		) string
 	}
 
+	loader schema.Loader
+
 	convertExamplesList []struct {
 		docs                       string
 		path                       examplePath
@@ -107,6 +110,12 @@ func (g *Generator) cliConverter() *cliConverter {
 		pluginHost:   g.pluginHost,
 		pcls:         map[string]translatedExample{},
 	}
+	if g.pluginHost != nil {
+		l := newLoader(g.pluginHost)
+		// Ensure azurerm resolves to azure for example:
+		l.aliasPackage(g.info.Name, string(g.pkg))
+		g.cliConverterState.loader = l
+	}
 	return g.cliConverterState
 }
 
@@ -389,8 +398,9 @@ func (cc *cliConverter) convertPCL(
 		opts = append(opts, pcl.SkipResourceTypechecking)
 		if cc.pluginHost != nil {
 			opts = append(opts, pcl.PluginHost(cc.pluginHost))
-			loader := newLoader(cc.pluginHost)
-			opts = append(opts, pcl.Loader(loader))
+		}
+		if cc.loader != nil {
+			opts = append(opts, pcl.Loader(cc.loader))
 		}
 		if cc.packageCache != nil {
 			opts = append(opts, pcl.Cache(cc.packageCache))

pkg/tfgen/convert_cli_test.go

@@ -15,27 +15,34 @@
 package tfgen
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
 	"os"
 	"path/filepath"
 	"runtime"
+	"strings"
 	"testing"
 
-	"encoding/json"
-
+	"github.com/blang/semver"
+	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
 	"github.com/hexops/autogold/v2"
 	"github.com/spf13/afero"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
-	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
-	bridgetesting "github.com/pulumi/pulumi-terraform-bridge/v3/internal/testing"
-	"github.com/pulumi/pulumi-terraform-bridge/v3/pkg/tfbridge"
-	sdkv2 "github.com/pulumi/pulumi-terraform-bridge/v3/pkg/tfshim/sdk-v2"
 	pschema "github.com/pulumi/pulumi/pkg/v3/codegen/schema"
 	"github.com/pulumi/pulumi/sdk/v3/go/common/diag"
 	"github.com/pulumi/pulumi/sdk/v3/go/common/diag/colors"
+	"github.com/pulumi/pulumi/sdk/v3/go/common/resource"
+	"github.com/pulumi/pulumi/sdk/v3/go/common/resource/plugin"
+	"github.com/pulumi/pulumi/sdk/v3/go/common/tokens"
+	"github.com/pulumi/pulumi/sdk/v3/go/common/workspace"
+
+	bridgetesting "github.com/pulumi/pulumi-terraform-bridge/v3/internal/testing"
+	"github.com/pulumi/pulumi-terraform-bridge/v3/pkg/tfbridge"
+	sdkv2 "github.com/pulumi/pulumi-terraform-bridge/v3/pkg/tfshim/sdk-v2"
+	shimv2 "github.com/pulumi/pulumi-terraform-bridge/v3/pkg/tfshim/sdk-v2"
 )
 
 func TestConvertViaPulumiCLI(t *testing.T) {
@@ -164,6 +171,7 @@ output "someOutput" {
 			Package:      info.Name,
 			Version:      info.Version,
 			Language:     Schema,
+			PluginHost:   &testPluginHost{},
 			ProviderInfo: info,
 			Root:         fs,
 			Sink: diag.DefaultSink(io.Discard, io.Discard, diag.FormatOptions{
@@ -213,4 +221,115 @@ Converted 100.00% of yaml examples (1/1)
 		withPrefix := tfbridge.ProviderInfo{Name: "p", ResourcePrefix: "prov"}
 		assert.Equal(t, filepath.Join(".", "prov.json"), c.mappingsFile(".", withPrefix))
 	})
+
+	// Taken from https://github.com/pulumi/pulumi-azure/issues/1698
+	//
+	// Emulate a case where pulumi name does not match the TF provider prefix, and one of the
+	// examples is referencing an unknown resource.
+	//
+	// Before the fix this would panic reaching out to PluginHost.ResolvePlugin.
+	t.Run("unknownResource", func(t *testing.T) {
+		md := []byte(strings.ReplaceAll(`
+# azurerm_web_pubsub_custom_certificate
+
+Manages an Azure Web PubSub Custom Certificate.
+
+## Example Usage
+
+%%%hcl
+
+resource "azurerm_web_pubsub_service" "example" {
+  name = "example-webpubsub"
+}
+
+resource "azurerm_web_pubsub_custom_certificate" "test" {
+  name = "example-cert"
+}
+
+%%%`, "%%%", "```"))
+		p := &schema.Provider{
+			ResourcesMap: map[string]*schema.Resource{
+				"azurerm_web_pubsub_custom_certificate": {
+					Schema: map[string]*schema.Schema{"name": {
+						Type:     schema.TypeString,
+						Optional: true,
+					}},
+				},
+			},
+		}
+		pi := tfbridge.ProviderInfo{
+			P:       shimv2.NewProvider(p),
+			Name:    "azurerm",
+			Version: "0.0.1",
+			Resources: map[string]*tfbridge.ResourceInfo{
+				"azurerm_web_pubsub_custom_certificate": {
+					Tok:  "azure:webpubsub/customCertificate:CustomCertificate",
+					Docs: &tfbridge.DocInfo{Markdown: md},
+				},
+			},
+		}
+		g, err := NewGenerator(GeneratorOptions{
+			Package:      "azure",
+			Version:      "0.0.1",
+			PluginHost:   &testPluginHost{},
+			Language:     Schema,
+			ProviderInfo: pi,
+			Root:         afero.NewBasePathFs(afero.NewOsFs(), t.TempDir()),
+			Sink: diag.DefaultSink(io.Discard, io.Discard, diag.FormatOptions{
+				Color: colors.Never,
+			}),
+		})
+		require.NoError(t, err)
+
+		err = g.Generate()
+		require.NoError(t, err)
+	})
+}
+
+type testPluginHost struct{}
+
+func (*testPluginHost) ServerAddr() string { panic("Unexpected call") }
+
+func (*testPluginHost) Log(diag.Severity, resource.URN, string, int32) {
+	panic("Unexpected call")
+}
+
+func (*testPluginHost) LogStatus(diag.Severity, resource.URN, string, int32) {
+	panic("Unexpected call")
 }
+
+func (*testPluginHost) Analyzer(tokens.QName) (plugin.Analyzer, error) { panic("Unexpected call") }
+
+func (*testPluginHost) PolicyAnalyzer(
+	tokens.QName, string, *plugin.PolicyAnalyzerOptions,
+) (plugin.Analyzer, error) {
+	panic("Unexpected call")
+}
+
+func (*testPluginHost) ListAnalyzers() []plugin.Analyzer { panic("Unexpected call") }
+
+func (*testPluginHost) Provider(tokens.Package, *semver.Version) (plugin.Provider, error) {
+	panic("Unexpected call")
+}
+
+func (*testPluginHost) CloseProvider(plugin.Provider) error { panic("Unexpected call") }
+
+func (*testPluginHost) LanguageRuntime(string, plugin.ProgramInfo) (plugin.LanguageRuntime, error) {
+	panic("Unexpected call")
+}
+
+func (*testPluginHost) EnsurePlugins([]workspace.PluginSpec, plugin.Flags) error {
+	panic("Unexpected call")
+}
+
+func (*testPluginHost) ResolvePlugin(
+	workspace.PluginKind, string, *semver.Version,
+) (*workspace.PluginInfo, error) {
+	panic("Unexpected call")
+}
+
+func (*testPluginHost) GetProjectPlugins() []workspace.ProjectPlugin { panic("Unexpected call") }
+func (*testPluginHost) SignalCancellation() error                    { panic("Unexpected call") }
+func (*testPluginHost) Close() error                                 { return nil }
+
+var _ plugin.Host = (*testPluginHost)(nil)

pkg/tfgen/generate.go

@@ -871,7 +871,6 @@ type GenerateOptions struct {
 
 // Generate creates Pulumi packages from the information it was initialized with.
 func (g *Generator) Generate() error {
-
 	// First gather up the entire package contents. This structure is complete and sufficient to hand off to the
 	// language-specific generators to create the full output.
 	pack, err := g.gatherPackage()

pkg/tfgen/loaders.go

@@ -16,19 +16,30 @@ package tfgen
 
 import (
 	"github.com/blang/semver"
-
 	"github.com/pulumi/pulumi/pkg/v3/codegen/schema"
 	"github.com/pulumi/pulumi/sdk/v3/go/common/resource/plugin"
 )
 
 type loader struct {
-	innerLoader   schema.Loader
-	emptyPackages map[string]bool
+	innerLoader     schema.Loader
+	emptyPackages   map[string]bool
+	aliasedPackages map[string]string
 }
 
 var _ schema.Loader = &loader{}
 
+func (l *loader) aliasPackage(alias string, canonicalName string) {
+	if l.aliasedPackages == nil {
+		l.aliasedPackages = map[string]string{}
+	}
+	l.aliasedPackages[alias] = canonicalName
+}
+
 func (l *loader) LoadPackage(name string, ver *semver.Version) (*schema.Package, error) {
+	if renamed, ok := l.aliasedPackages[name]; ok {
+		name = renamed
+	}
+
 	if l.emptyPackages[name] {
 		return &schema.Package{
 			Name:    name,