Nest incompatible provider protocol error to include dynamic custom msg

command/init.go

@@ -11,6 +11,7 @@ import (
 	"github.com/posener/complete"
 	"github.com/zclconf/go-cty/cty"
 
+	"github.com/hashicorp/errwrap"
 	"github.com/hashicorp/terraform/backend"
 	"github.com/hashicorp/terraform/config"
 	"github.com/hashicorp/terraform/configs"
@@ -449,10 +450,15 @@ func (c *InitCommand) getProviders(path string, state *states.State, upgrade boo
 			_, err := c.providerInstaller.Get(provider, reqd.Versions)
 
 			if err != nil {
-				switch err {
+				constraint := reqd.Versions.String()
-				case discovery.ErrorNoSuchProvider:
+				if constraint == "" {
+					constraint = "(any version)"
+				}
+
+				switch {
+				case err == discovery.ErrorNoSuchProvider:
 					c.Ui.Error(fmt.Sprintf(errProviderNotFound, provider, DefaultPluginVendorDir))
-				case discovery.ErrorNoSuitableVersion:
+				case err == discovery.ErrorNoSuitableVersion:
 					if reqd.Versions.Unconstrained() {
 						// This should never happen, but might crop up if we catch
 						// the releases server in a weird state where the provider's
@@ -462,14 +468,21 @@ func (c *InitCommand) getProviders(path string, state *states.State, upgrade boo
 					} else {
 						c.Ui.Error(fmt.Sprintf(errProviderVersionsUnsuitable, provider, reqd.Versions))
 					}
-				case discovery.ErrorNoVersionCompatible:
+				case errwrap.Contains(err, discovery.ErrorVersionIncompatible.Error()):
-					// FIXME: This error message is sub-awesome because we don't
+					// Attempt to fetch nested error to display to the user which versions
-					// have enough information here to tell the user which versions
+					// we considered and which versions might be compatible. Otherwise,
-					// we considered and which versions might be compatible.
+					// we'll just display a generic version incompatible msg
-					constraint := reqd.Versions.String()
+					incompatErr := errwrap.GetType(err, fmt.Errorf(""))
-					if constraint == "" {
+					if incompatErr != nil {
-						constraint = "(any version)"
+						c.Ui.Error(incompatErr.Error())
+					} else {
+						// Generic version incompatible msg
+						c.Ui.Error(fmt.Sprintf(errProviderIncompatible, provider, constraint))
 					}
+					// Reset nested errors
+					err = discovery.ErrorVersionIncompatible
+				case err == discovery.ErrorNoVersionCompatible:
+					// Generic version incompatible msg
 					c.Ui.Error(fmt.Sprintf(errProviderIncompatible, provider, constraint))
 				default:
 					c.Ui.Error(fmt.Sprintf(errProviderInstallError, provider, err.Error(), DefaultPluginVendorDir))

plugin/discovery/error.go

@@ -22,6 +22,11 @@ const ErrorNoSuitableVersion = Error("no suitable version is available")
 // version of Terraform.
 const ErrorNoVersionCompatible = Error("no available version is compatible with this version of Terraform")
 
+// ErrorVersionIncompatible indicates that all of the versions within the
+// constraints are not compatible with the current version of Terrafrom, though
+// there does exist a version outside of the constaints that is compatible.
+const ErrorVersionIncompatible = Error("incompatible provider version")
+
 // ErrorNoSuchProvider indicates that no provider exists with a name given
 const ErrorNoSuchProvider = Error("no provider exists with the given name")
 

plugin/discovery/get.go

@@ -13,6 +13,7 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/hashicorp/errwrap"
 	getter "github.com/hashicorp/go-getter"
 	multierror "github.com/hashicorp/go-multierror"
 	"github.com/hashicorp/terraform/httpclient"
@@ -168,16 +169,22 @@ func (i *ProviderInstaller) Get(provider string, req Constraints) (PluginMeta, e
 		}
 
 		// Prompt version suggestion to UI based on closest protocol match
-		closestVersion := VersionStr(closestMatch.Version).MustParse()
 		var errMsg string
+		closestVersion := VersionStr(closestMatch.Version).MustParse()
 		if v.NewerThan(closestVersion) {
 			errMsg = providerProtocolTooNew
 		} else {
 			errMsg = providerProtocolTooOld
 		}
-		i.Ui.Error(fmt.Sprintf(errMsg, provider, v.String(), tfversion.String(),
+
-			closestVersion.String(), closestVersion.MinorUpgradeConstraintStr()))
+		constraintStr := req.String()
-		return PluginMeta{}, ErrorNoVersionCompatible
+		if constraintStr == "" {
+			constraintStr = "(any version)"
+		}
+
+		return PluginMeta{}, errwrap.Wrap(ErrorVersionIncompatible, fmt.Errorf(fmt.Sprintf(
+			errMsg, provider, v.String(), tfversion.String(),
+			closestVersion.String(), closestVersion.MinorUpgradeConstraintStr(), constraintStr)))
 	}
 
 	downloadURLs, err := i.listProviderDownloadURLs(providerSource, versionMeta.Version)
@@ -582,27 +589,41 @@ func getFile(url string) ([]byte, error) {
 	return data, nil
 }
 
-// ProviderProtocolTooOld is a message sent to the CLI UI if the provider's
+// providerProtocolTooOld is a message sent to the CLI UI if the provider's
 // supported protocol versions are too old for the user's version of terraform,
 // but an older version of the provider is compatible.
-const providerProtocolTooOld = `Provider %q v%s is not compatible with Terraform %s.
+const providerProtocolTooOld = `
+[reset][bold][red]Provider %q v%s is not compatible with Terraform %s.[reset][red]
 
-Provider version %s is the earliest compatible version.
+Provider version %s is the earliest compatible version. Select it with 
-Select it with the following version constraint:
+the following version constraint:
 
-    version = %q
+	version = %q
+
+Terraform checked all of the plugin versions matching the given constraint:
+    %s
+
+Consult the documentation for this provider for more information on
+compatibility between provider and Terraform versions.
 `
 
-// ProviderProtocolTooNew is a message sent to the CLI UI if the provider's
+// providerProtocolTooNew is a message sent to the CLI UI if the provider's
 // supported protocol versions are too new for the user's version of terraform,
 // and the user could either upgrade terraform or choose an older version of the
 // provider
-const providerProtocolTooNew = `Provider %q v%s is not compatible with Terraform %s.
+const providerProtocolTooNew = `
+[reset][bold][red]Provider %q v%s is not compatible with Terraform %s.[reset][red]
 
-Provider version v%s is the latest compatible version. Select 
+Provider version %s is the latest compatible version. Select it with 
-it with the following constraint:
+the following constraint:
 
     version = %q
 
+Terraform checked all of the plugin versions matching the given constraint:
+    %s
+
+Consult the documentation for this provider for more information on
+compatibility between provider and Terraform versions.
+
 Alternatively, upgrade to the latest version of Terraform for compatibility with newer provider releases.
 `