Add download_retry_count for direct and network_mirror in CLI configuration (#3368)

Signed-off-by: Andrei Ciobanu <andrei.ciobanu@opentofu.org>

cmd/tofu/commands.go

@@ -123,7 +123,10 @@ func initCommands(
 
 		AllowExperimentalFeatures: experimentsAreAllowed(),
 
-		ProviderSourceLocationConfig: providerSourceLocationConfig(),
+		// ProviderSourceLocationConfig is used for some commands that do not make
+		// use of the OpenTofu configuration files. Therefore, there is no way to configure
+		// the retries from other places than env vars.
+		ProviderSourceLocationConfig: providerSourceLocationConfigFromEnv(),
 	}
 
 	// The command list is included in the tofu -help

cmd/tofu/provider_source.go

@@ -12,7 +12,6 @@ import (
 	"net/url"
 	"os"
 	"path/filepath"
-	"strconv"
 
 	"github.com/apparentlymart/go-userdirs/userdirs"
 	"github.com/opentofu/svchost/disco"
@@ -61,7 +60,7 @@ func explicitProviderSource(
 
 	log.Printf("[DEBUG] Explicit provider installation configuration is set")
 	for _, methodConfig := range config.Methods {
-		source, moreDiags := providerSourceForCLIConfigLocation(ctx, methodConfig.Location, registryClientConfig, services, getOCICredsPolicy)
+		source, moreDiags := providerSourceForCLIConfigLocation(ctx, methodConfig.Location, methodConfig.Retries, registryClientConfig, services, getOCICredsPolicy)
 		diags = diags.Append(moreDiags)
 		if moreDiags.HasErrors() {
 			continue
@@ -208,7 +207,7 @@ func implicitProviderSource(
 	// local copy will take precedence.
 	searchRules = append(searchRules, getproviders.MultiSourceSelector{
 		Source: getproviders.NewMemoizeSource(
-			getproviders.NewRegistrySource(ctx, services, newRegistryHTTPClient(ctx, registryClientConfig), providerSourceLocationConfig()),
+			getproviders.NewRegistrySource(ctx, services, newRegistryHTTPClient(ctx, registryClientConfig), providerSourceLocationConfigFromEnv()),
 		),
 		Exclude: directExcluded,
 	})
@@ -219,13 +218,14 @@ func implicitProviderSource(
 func providerSourceForCLIConfigLocation(
 	ctx context.Context,
 	loc cliconfig.ProviderInstallationLocation,
+	locationRetries cliconfig.ProviderInstallationMethodRetries,
 	registryClientConfig *cliconfig.RegistryProtocolsConfig,
 	services *disco.Disco,
 	makeOCICredsPolicy ociCredsPolicyBuilder,
 ) (getproviders.Source, tfdiags.Diagnostics) {
 	if loc == cliconfig.ProviderInstallationDirect {
 		return getproviders.NewMemoizeSource(
-			getproviders.NewRegistrySource(ctx, services, newRegistryHTTPClient(ctx, registryClientConfig), providerSourceLocationConfig()),
+			getproviders.NewRegistrySource(ctx, services, newRegistryHTTPClient(ctx, registryClientConfig), providerSourceLocationConfig(locationRetries)),
 		), nil
 	}
 
@@ -259,7 +259,7 @@ func providerSourceForCLIConfigLocation(
 		// this client is not suitable for the HTTP mirror source, so we
 		// don't use this client directly.
 		httpTimeout := newRegistryHTTPClient(ctx, registryClientConfig).HTTPClient.Timeout
-		return getproviders.NewHTTPMirrorSource(ctx, url, services.CredentialsSource(), httpTimeout, providerSourceLocationConfig()), nil
+		return getproviders.NewHTTPMirrorSource(ctx, url, services.CredentialsSource(), httpTimeout, providerSourceLocationConfig(locationRetries)), nil
 
 	case cliconfig.ProviderInstallationOCIMirror:
 		mappingFunc := loc.RepositoryMapping
@@ -300,33 +300,28 @@ func providerDevOverrides(configs []*cliconfig.ProviderInstallation) map[addrs.P
 	return configs[0].DevOverrides
 }
 
-const (
-	// providerDownloadRetryCountEnvName is the environment variable name used to customize
-	// the HTTP retry count for module downloads.
-	providerDownloadRetryCountEnvName = "TF_PROVIDER_DOWNLOAD_RETRY"
-
-	providerDownloadDefaultRetry = 2
-)
-
-// providerDownloadRetry will attempt for requests with retryable errors, like 502 status codes
-func providerDownloadRetry() int {
-	res := providerDownloadDefaultRetry
-	if v := os.Getenv(providerDownloadRetryCountEnvName); v != "" {
-		retry, err := strconv.Atoi(v)
-		if err == nil && retry > 0 {
-			res = retry
-		}
-	}
-	return res
-}
-
 // providerSourceLocationConfig is meant to build a global configuration for the
 // remote locations to download a provider from. This is built out of the
 // TF_PROVIDER_DOWNLOAD_RETRY env variable and is meant to be passed through
 // [getproviders.Source] all the way down to the [getproviders.PackageLocation]
 // to be able to tweak the configurations of the http clients used there.
-func providerSourceLocationConfig() getproviders.LocationConfig {
+func providerSourceLocationConfig(locationRetries cliconfig.ProviderInstallationMethodRetries) getproviders.LocationConfig {
+	// If there is no configuration for the retries in .tofurc, get the one from env variable
+	retries, configured := locationRetries()
+	if !configured {
+		retries = cliconfig.ProviderDownloadRetries()
+	}
 	return getproviders.LocationConfig{
-		ProviderDownloadRetries: providerDownloadRetry(),
+		ProviderDownloadRetries: retries,
+	}
+}
+
+// providerSourceLocationConfigFromEnv is similar to providerSourceLocationConfig but does not
+// take into account the information from the configuration. This is like so because for some
+// commands, there is no specific tofurc configuration for the retry, so we want to use the
+// env variable if defined and if not, its default.
+func providerSourceLocationConfigFromEnv() getproviders.LocationConfig {
+	return getproviders.LocationConfig{
+		ProviderDownloadRetries: cliconfig.ProviderDownloadRetries(),
 	}
 }

cmd/tofu/provider_source_test.go

@@ -7,8 +7,11 @@ package main
 
 import (
 	"context"
+	"net/http"
+	"net/http/httptest"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 	"time"
 
@@ -160,6 +163,121 @@ func TestProviderSource(t *testing.T) {
 	}
 }
 
+// TestInitProviderSourceForCLIConfigLocationWithRetries tests how the retries are handled and passed over to the
+// [getproviders.PackageLocation].
+// Normally, this should have been an e2e test, but there is no easy way to mock a `direct` registry
+// to be able to test that the retries actually work properly.
+//
+// This test contains no tests for [cliconfig.ProviderInstallationNetworkMirror] on purpose since
+// there is no way to create [getproviders.HTTPMirrorSource]
+// with an on-the-fly generated TLS certificate since it's required by the
+// [getproviders.HTTPMirrorSource] inner working.
+// Instead, the retries functionality for `network_mirror` is tested into an e2e called
+// "TestProviderNetworkMirrorRetries" since that way we were able to provide the TLS certificate
+// into the child process instead.
+func TestInitProviderSourceForCLIConfigLocationWithRetries(t *testing.T) {
+	registryHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch r.URL.Path {
+		case "/providers/v1/test/exists/0.0.0/download/foo_os/bar_arch":
+			_, _ = w.Write([]byte(`{"os":"foo_os","arch":"bar_arch","download_url":"/providers/v1/test/exists_0.0.0.zip","shasum":"4cbc33c22abdebe3a3679666d4052ec95c40bd8904a9458f90cf934363a14cc7"}`))
+		case "/providers/v1/test/exists_0.0.0.zip":
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		default:
+			w.WriteHeader(http.StatusNotFound)
+		}
+	})
+	cases := map[string]struct {
+		methodType     cliconfig.ProviderInstallationLocation
+		tofurcRetries  cliconfig.ProviderInstallationMethodRetries
+		envVars        map[string]string
+		expectedErrMsg string
+	}{
+		"no tofurc.direct.download_retry_count configured, no TF_PROVIDER_DOWNLOAD_RETRY, default TF_PROVIDER_DOWNLOAD_RETRY used": {
+			methodType: cliconfig.ProviderInstallationDirect,
+			tofurcRetries: func() (int, bool) {
+				return 0, false
+			},
+			envVars:        nil,
+			expectedErrMsg: "/providers/v1/test/exists_0.0.0.zip giving up after 3 attempt(s)",
+		},
+		"no tofurc.direct.download_retry_count, TF_PROVIDER_DOWNLOAD_RETRY defined, TF_PROVIDER_DOWNLOAD_RETRY used": {
+			methodType: cliconfig.ProviderInstallationDirect,
+			tofurcRetries: func() (int, bool) {
+				return 0, false
+			},
+			envVars: map[string]string{
+				"TF_PROVIDER_DOWNLOAD_RETRY": "1",
+			},
+			expectedErrMsg: "/providers/v1/test/exists_0.0.0.zip giving up after 2 attempt(s)",
+		},
+		"defined tofurc.direct.download_retry_count as 0, no TF_PROVIDER_DOWNLOAD_RETRY, tofurc used": {
+			methodType: cliconfig.ProviderInstallationDirect,
+			tofurcRetries: func() (int, bool) {
+				return 0, true
+			},
+			envVars:        nil,
+			expectedErrMsg: "/providers/v1/test/exists_0.0.0.zip giving up after 1 attempt(s)",
+		},
+		"defined tofurc.direct.download_retry_count as 1, no TF_PROVIDER_DOWNLOAD_RETRY, tofurc used": {
+			methodType: cliconfig.ProviderInstallationDirect,
+			tofurcRetries: func() (int, bool) {
+				return 1, true
+			},
+			envVars:        nil,
+			expectedErrMsg: "/providers/v1/test/exists_0.0.0.zip giving up after 2 attempt(s)",
+		},
+		"defined tofurc.direct.download_retry_count as 1, TF_PROVIDER_DOWNLOAD_RETRY defined as 2, tofurc used": {
+			methodType: cliconfig.ProviderInstallationDirect,
+			tofurcRetries: func() (int, bool) {
+				return 1, true
+			},
+			envVars: map[string]string{
+				"TF_PROVIDER_DOWNLOAD_RETRY": "2",
+			},
+			expectedErrMsg: "/providers/v1/test/exists_0.0.0.zip giving up after 2 attempt(s)",
+		},
+	}
+	for name, tt := range cases {
+		t.Run(name, func(t *testing.T) {
+			methodType := tt.methodType
+			retries := tt.tofurcRetries // This is what simulates the configuration of .tofurc
+			for k, v := range tt.envVars {
+				t.Setenv(k, v)
+			}
+
+			server := httptest.NewServer(registryHandler)
+			defer server.Close()
+			disco := disco.New(disco.WithHTTPClient(server.Client()))
+			disco.ForceHostServices("local.testing", map[string]any{
+				"providers.v1": server.URL + "/providers/v1/",
+			})
+
+			providerSrc, diags := providerSourceForCLIConfigLocation(t.Context(), methodType, retries, &cliconfig.RegistryProtocolsConfig{}, disco, nil)
+			if diags.HasErrors() {
+				t.Fatalf("unexpected error creating the provider source: %s", diags)
+			}
+			provider := addrs.MustParseProviderSourceString("local.testing/test/exists")
+			platform := getproviders.Platform{OS: "foo_os", Arch: "bar_arch"}
+			packageMeta, err := providerSrc.PackageMeta(t.Context(), provider, getproviders.UnspecifiedVersion, platform)
+			if err != nil {
+				t.Fatalf("unexpected error getting the package meta information: %s", err)
+			}
+			// We nullify the authentication since the meaning of this test is not to
+			packageMeta.Authentication = nil
+
+			instDir := t.TempDir()
+			_, err = packageMeta.Location.InstallProviderPackage(t.Context(), packageMeta, instDir, nil)
+			if err == nil {
+				t.Fatalf("expected to get an error from the installation of the provider but got nothing")
+			}
+			if contains := tt.expectedErrMsg; !strings.Contains(err.Error(), contains) {
+				t.Fatalf("expected the error from the installation to contain %q but it didn't: %s", contains, err)
+			}
+		})
+	}
+}
+
 func TestConfigureProviderDownloadRetry(t *testing.T) {
 	tests := []struct {
 		name    string
@@ -170,7 +288,7 @@ func TestConfigureProviderDownloadRetry(t *testing.T) {
 		{
 			name: "when no TF_PROVIDER_DOWNLOAD_RETRY env var, default retry attempts used for provider download",
 			expectedConfig: getproviders.LocationConfig{
-				ProviderDownloadRetries: providerDownloadDefaultRetry,
+				ProviderDownloadRetries: 2,
 			},
 		},
 		{
@@ -191,7 +309,9 @@ func TestConfigureProviderDownloadRetry(t *testing.T) {
 			}
 
 			// Call the function under test
-			got := providerSourceLocationConfig()
+			got := providerSourceLocationConfig(func() (int, bool) {
+				return 0, false
+			})
 
 			if diff := cmp.Diff(tt.expectedConfig, got); diff != "" {
 				t.Fatalf("expected no diff. got:\n%s", diff)

internal/command/cliconfig/cliconfig.go

@@ -21,6 +21,7 @@ import (
 	"log"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 
 	"github.com/hashicorp/hcl"
@@ -501,3 +502,23 @@ func cliConfigFileOverride() string {
 	}
 	return configFilePath
 }
+
+const (
+	// providerDownloadRetryCountEnvName is the environment variable name used to customize
+	// the HTTP retry count for module downloads.
+	providerDownloadRetryCountEnvName = "TF_PROVIDER_DOWNLOAD_RETRY"
+
+	providerDownloadDefaultRetry = 2
+)
+
+// ProviderDownloadRetries will attempt for requests with retryable errors, like 502 status codes
+func ProviderDownloadRetries() int {
+	r := providerDownloadDefaultRetry
+	if v := os.Getenv(providerDownloadRetryCountEnvName); v != "" {
+		retry, err := strconv.Atoi(v)
+		if err == nil && retry > 0 {
+			r = retry
+		}
+	}
+	return r
+}

internal/command/cliconfig/credentials_test.go

@@ -153,7 +153,7 @@ func TestCredentialsForHost(t *testing.T) {
 		}
 	})
 
-	t.Run("periods are ok", func(t *testing.T) {
+	t.Run("periods are Ok", func(t *testing.T) {
 		envName := "TF_TOKEN_configured.example.com"
 		expectedToken := "configured-by-env"
 

internal/command/cliconfig/provider_installation.go

@@ -149,11 +149,13 @@ func decodeProviderInstallationFromConfig(hclFile *hclast.File) ([]*ProviderInst
 			methodTypeStr := methodBlock.Keys[0].Token.Value().(string)
 			var location ProviderInstallationLocation
 			var include, exclude []string
+			var retriesF ProviderInstallationMethodRetries
 			switch methodTypeStr {
 			case "direct":
 				type BodyContent struct {
 					Include         []string `hcl:"include"`
 					Exclude         []string `hcl:"exclude"`
+					DownloadRetries *int     `hcl:"download_retry_count"`
 				}
 				var bodyContent BodyContent
 				err := hcl.DecodeObject(&bodyContent, methodBody)
@@ -168,6 +170,12 @@ func decodeProviderInstallationFromConfig(hclFile *hclast.File) ([]*ProviderInst
 				location = ProviderInstallationDirect
 				include = bodyContent.Include
 				exclude = bodyContent.Exclude
+				retriesF = func() (int, bool) {
+					if bodyContent.DownloadRetries == nil {
+						return 0, false
+					}
+					return *bodyContent.DownloadRetries, true
+				}
 			case "filesystem_mirror":
 				type BodyContent struct {
 					Path    string   `hcl:"path"`
@@ -200,6 +208,7 @@ func decodeProviderInstallationFromConfig(hclFile *hclast.File) ([]*ProviderInst
 					URL             string   `hcl:"url"`
 					Include         []string `hcl:"include"`
 					Exclude         []string `hcl:"exclude"`
+					DownloadRetries *int     `hcl:"download_retry_count"`
 				}
 				var bodyContent BodyContent
 				err := hcl.DecodeObject(&bodyContent, methodBody)
@@ -222,6 +231,12 @@ func decodeProviderInstallationFromConfig(hclFile *hclast.File) ([]*ProviderInst
 				location = ProviderInstallationNetworkMirror(bodyContent.URL)
 				include = bodyContent.Include
 				exclude = bodyContent.Exclude
+				retriesF = func() (int, bool) {
+					if bodyContent.DownloadRetries == nil {
+						return 0, false
+					}
+					return *bodyContent.DownloadRetries, true
+				}
 			case "oci_mirror":
 				var moreDiags tfdiags.Diagnostics
 				location, include, exclude, moreDiags = decodeOCIMirrorInstallationMethodBlock(methodBody)
@@ -229,6 +244,9 @@ func decodeProviderInstallationFromConfig(hclFile *hclast.File) ([]*ProviderInst
 				if moreDiags.HasErrors() {
 					continue
 				}
+				// NOTE: We want to introduce a retry and a timeout for the oci_mirror block too, but that needs
+				// a different design than the one we have for direct and network_mirror.
+				// Details in: https://github.com/opentofu/opentofu/issues/3392
 			case "dev_overrides":
 				if len(pi.Methods) > 0 {
 					// We require dev_overrides to appear first if it's present,
@@ -289,6 +307,7 @@ func decodeProviderInstallationFromConfig(hclFile *hclast.File) ([]*ProviderInst
 				Location: location,
 				Include:  include,
 				Exclude:  exclude,
+				Retries:  retriesF,
 			})
 		}
 
@@ -564,6 +583,7 @@ type ProviderInstallationMethod struct {
 	Location ProviderInstallationLocation
 	Include  []string `hcl:"include"`
 	Exclude  []string `hcl:"exclude"`
+	Retries  ProviderInstallationMethodRetries
 }
 
 // ProviderInstallationLocation is an interface type representing the
@@ -639,3 +659,12 @@ func (i ProviderInstallationOCIMirror) GoString() string {
 	// mismatches in tests, so just naming the type is good enough for now.
 	return "cliconfig.ProviderInstallationNetworkMirror{/*...*/}"
 }
+
+// ProviderInstallationMethodRetries defines the function to return the
+// configured, or lack of, retries (`download_retry_count`) configured for
+// a provider installation method.
+// This will return a number >= 0 and a bool in case the value actually
+// comes from the CLI configuration. When the bool returned is [false], the
+// number returned will be 0, meaning that the configuration was not
+// specified.
+type ProviderInstallationMethodRetries func() (int, bool)

internal/command/cliconfig/provider_installation_test.go

@@ -37,6 +37,9 @@ func TestLoadConfig_providerInstallation(t *testing.T) {
 								Location: ProviderInstallationNetworkMirror("https://tf-Mirror.example.com/"),
 								Include:  []string{"registry.opentofu.org/*/*"},
 								Exclude:  []string{"registry.OpenTofu.org/foobar/*"},
+								Retries: func() (int, bool) {
+									return 2, true
+								},
 							},
 							{
 								Location: ProviderInstallationFilesystemMirror("/tmp/example2"),
@@ -44,6 +47,9 @@ func TestLoadConfig_providerInstallation(t *testing.T) {
 							{
 								Location: ProviderInstallationDirect,
 								Exclude:  []string{"example.com/*/*"},
+								Retries: func() (int, bool) {
+									return 3, true
+								},
 							},
 						},
 
@@ -55,7 +61,17 @@ func TestLoadConfig_providerInstallation(t *testing.T) {
 				},
 			}
 
-			if diff := cmp.Diff(want, got); diff != "" {
+			if diff := cmp.Diff(want, got, cmp.Comparer(func(a, b ProviderInstallationMethodRetries) bool {
+				if (a == nil && b != nil) || (a != nil && b == nil) {
+					return false
+				}
+				if a == nil && b == nil {
+					return true
+				}
+				ar, aok := a()
+				br, bok := b()
+				return ar == br && aok == bok
+			})); diff != "" {
 				t.Errorf("wrong result\n%s", diff)
 			}
 		})

internal/command/cliconfig/testdata/provider-installation

@@ -11,11 +11,13 @@ provider_installation {
     url     = "https://tf-Mirror.example.com/"
     include = ["registry.opentofu.org/*/*"]
     exclude = ["registry.OpenTofu.org/foobar/*"]
+    download_retry_count = 2
   }
   filesystem_mirror {
     path    = "/tmp/example2"
   }
   direct {
     exclude = ["example.com/*/*"]
+    download_retry_count = 3
   }
 }

internal/command/cliconfig/testdata/provider-installation.json

@@ -11,13 +11,15 @@
     "network_mirror": [{
       "url": "https://tf-Mirror.example.com/",
       "include": ["registry.opentofu.org/*/*"],
-      "exclude": ["registry.OpenTofu.org/foobar/*"]
+      "exclude": ["registry.OpenTofu.org/foobar/*"],
+      "download_retry_count": 2
     }],
     "filesystem_mirror": [{
       "path": "/tmp/example2"
     }],
     "direct": [{
-      "exclude": ["example.com/*/*"]
+      "exclude": ["example.com/*/*"],
+      "download_retry_count": 3
     }]
   }
 }

internal/command/e2etest/provider_network_mirror_test.go

@@ -0,0 +1,148 @@
+// Copyright (c) The OpenTofu Authors
+// SPDX-License-Identifier: MPL-2.0
+// Copyright (c) 2023 HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package e2etest
+
+import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+
+	"github.com/opentofu/opentofu/internal/e2e"
+)
+
+// TestProviderNetworkMirrorRetries checks that the retries configuration for downloading the
+// provider from a network mirror source is handled correctly alone and also together with
+// the TF_PROVIDER_DOWNLOAD_RETRY env var.
+//
+// This is testing the same thing as TestInitProviderSourceForCLIConfigLocationWithRetries but
+// it's an e2e test instead because there is no way to inject the TLS certificate properly into
+// the underlying implementation that talks with a remote network mirror source.
+func TestProviderNetworkMirrorRetries(t *testing.T) {
+	// Our typical rule for external service access in e2etests is that it's okay
+	// to access servers run by the OpenTofu project when TF_ACC=1 is set in the
+	// environment. However, this particular test is checking a network mirror source
+	// that needs to be configured with a TLS certificate and that certificate to be given
+	// in the `tofu` child process env vars to be used for talking with the server.
+	// The entirety of this process can be done without actual network access so it can run
+	// without the TF_ACC=1.
+	//
+	// We restrict this for only linux_amd64 to make it easier to maintain since the whole purpose
+	// of the test has nothing to do with the actual platform it runs on.
+	//
+	// The fake server uses a locally-generated TLS certificate and so we'll need to
+	// override the trusted certs for the child process so it can be used successfully.
+	// The Go toolchain only allows doing that by environment variable on Unix systems
+	// other than macOS.
+	// Additionally, for ease of maintenance, the stubbed data inside this test is only
+	// for linux_amd64 so we cannot run this for other platforms that still support the
+	// previously mentioned limitation.
+	if runtime.GOOS != "linux" || runtime.GOARCH != "amd64" {
+		t.Skip("this test is suitable only for linux_amd64")
+	}
+	networkMirrorHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch r.URL.Path {
+		case "/example.com/test/test/index.json":
+			w.Header().Add("Content-Type", "application/json")
+			_, _ = w.Write([]byte(`{"versions":{"0.0.1":{}}}`))
+			return
+		case "/example.com/test/test/0.0.1.json":
+			w.Header().Add("Content-Type", "application/json")
+			_, _ = w.Write([]byte(`{"archives": {"linux_amd64": {"url": "terraform-provider-test_0.0.1_linux_amd64.zip","hashes": []}}}`))
+			return
+		case "/example.com/test/test/terraform-provider-test_0.0.1_linux_amd64.zip":
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		default:
+			w.WriteHeader(http.StatusNotFound)
+		}
+	})
+
+	cases := map[string]struct {
+		tofurcRetriesConfigEntry string
+		envVars                  map[string]string
+		expectedErrMsg           string
+	}{
+		"no tofurc.network_mirror.download_retry_count, no TF_PROVIDER_DOWNLOAD_RETRY, default TF_PROVIDER_DOWNLOAD_RETRY used": {
+			tofurcRetriesConfigEntry: "",
+			envVars:                  nil,
+			expectedErrMsg:           "/example.com/test/test/terraform-provider-test_0.0.1_linux_amd64.zip giving up after 3 attempt(s)",
+		},
+		"no tofurc.network_mirror.download_retry_count, TF_PROVIDER_DOWNLOAD_RETRY defined, TF_PROVIDER_DOWNLOAD_RETRY used": {
+			tofurcRetriesConfigEntry: "",
+			envVars: map[string]string{
+				"TF_PROVIDER_DOWNLOAD_RETRY": "1",
+			},
+			expectedErrMsg: "/example.com/test/test/terraform-provider-test_0.0.1_linux_amd64.zip giving up after 2 attempt(s)",
+		},
+		"defined tofurc.network_mirror.download_retry_count as 0, no TF_PROVIDER_DOWNLOAD_RETRY, tofurc used": {
+			tofurcRetriesConfigEntry: "download_retry_count = 0",
+			envVars:                  nil,
+			expectedErrMsg:           "/example.com/test/test/terraform-provider-test_0.0.1_linux_amd64.zip giving up after 1 attempt(s)",
+		},
+		"defined tofurc.network_mirror.download_retry_count as 1, no TF_PROVIDER_DOWNLOAD_RETRY, tofurc used": {
+			tofurcRetriesConfigEntry: "download_retry_count = 1",
+			envVars:                  nil,
+			expectedErrMsg:           "/example.com/test/test/terraform-provider-test_0.0.1_linux_amd64.zip giving up after 2 attempt(s)",
+		},
+		"defined tofurc.network_mirror.download_retry_count as 1, TF_PROVIDER_DOWNLOAD_RETRY defined as 2, tofurc used": {
+			tofurcRetriesConfigEntry: "download_retry_count = 1",
+			envVars: map[string]string{
+				"TF_PROVIDER_DOWNLOAD_RETRY": "2",
+			},
+			expectedErrMsg: "/example.com/test/test/terraform-provider-test_0.0.1_linux_amd64.zip giving up after 2 attempt(s)",
+		},
+	}
+	for name, tt := range cases {
+		t.Run(name, func(t *testing.T) {
+			server := httptest.NewTLSServer(networkMirrorHandler)
+			defer server.Close()
+			registryAddr := server.URL
+
+			// We need to pass both our fake registry server's certificate and the CLI config
+			// for interacting with it to the child process using some temporary files on disk.
+			tempDir := t.TempDir()
+			certFile := filepath.Join(tempDir, "testserver.crt")
+			if err := writeCertificatePEMFile(certFile, server.Certificate()); err != nil {
+				t.Fatalf("failed to create temporary certificate file: %s", err)
+			}
+			cliConfigFile := filepath.Join(tempDir, "cliconfig.tfrc")
+			cliConfigSrc := fmt.Sprintf(`
+		provider_installation {
+			network_mirror {
+                url = "%s"
+				%s
+			}
+		}
+	`, registryAddr, tt.tofurcRetriesConfigEntry)
+			if err := os.WriteFile(cliConfigFile, []byte(cliConfigSrc), os.ModePerm); err != nil {
+				t.Fatalf("failed to create temporary CLI configuration file: %s", err)
+			}
+			dataDir := filepath.Join(tempDir, ".terraform")
+
+			tf := e2e.NewBinary(t, tofuBin, "testdata/provider-network-mirror")
+			tf.AddEnv("SSL_CERT_FILE=" + certFile)
+			tf.AddEnv("TF_CLI_CONFIG_FILE=" + cliConfigFile)
+			tf.AddEnv("TF_DATA_DIR=" + dataDir)
+			for k, v := range tt.envVars {
+				tf.AddEnv(fmt.Sprintf("%s=%s", k, v))
+			}
+			_, stderr, err := tf.Run("init", "-backend=false")
+			if err == nil {
+				t.Fatalf("expected `tofu init` to fail but got no error")
+			}
+			t.Logf("stderr:\n%s", stderr)
+			cleanStderr := SanitizeStderr(stderr)
+			if contains := tt.expectedErrMsg; !strings.Contains(cleanStderr, contains) {
+				t.Fatalf("expected the error from the installation to contain %q but it doesn't", contains)
+			}
+		})
+	}
+}

internal/command/e2etest/testdata/provider-network-mirror/main.tf

@@ -0,0 +1,8 @@
+terraform {
+  required_providers {
+    test = {
+      source  = "example.com/test/test"
+      version = "0.0.1"
+    }
+  }
+}

website/docs/cli/config/config-file.mdx

@@ -278,6 +278,29 @@ identity, but a network mirror with a TLS certificate can potentially serve
 modified copies of upstream providers with malicious content.
 :::
 
+The `direct` and `network_mirror` methods support an additional argument
+`download_retry_count`. When specified, it will be used to retry downloading
+the provider binary in case of retryable errors (connection reset and a range of 500 errors).
+```hcl
+provider_installation {
+  network_mirror {
+    url                  = "https://example.com/"
+    include              = ["example.com/*/*"]
+    download_retry_count = 2
+  }
+  direct {
+    exclude              = ["example.com/*/*"]
+    download_retry_count = 3
+  }
+}
+```
+You can use this argument to disable fully the retries in case of a specific method (`download_retry_count = 0`).
+:::info
+When used together with [`TF_PROVIDER_DOWNLOAD_RETRY`](./environment-variables.mdx#tf_provider_download_retry), the configuration value
+will be used for each method that it is configured with. For the methods
+with no such configuration, the environment variable will be used instead.
+:::
+
 OpenTofu will try all of the specified methods whose include and exclude
 patterns match a given provider, and select the newest version available across
 all of those methods that matches the version constraint given in each

website/docs/cli/config/environment-variables.mdx

@@ -165,7 +165,9 @@ For more details on `.terraformignore`, please see [Excluding Files from Upload
 Set `TF_PROVIDER_DOWNLOAD_RETRY` to configure the max number of request retries
 the remote provider client will attempt for client connection errors or
 500-range responses that are safe to retry.
-
+:::info
+This will be used only for the methods without the argument `download_retry_count` specified in [OpenTofu CLI configuration file](./config-file.mdx#explicit-installation-method-configuration).
+:::
 ```shell
 export TF_PROVIDER_DOWNLOAD_RETRY=3
 ```