chore: Cherry pick #4474 into release-0.27 (#4475)

Co-authored-by: Stas Ostrovskyi <stas.ostrovskyy@gmail.com>

server/core/terraform/terraform_client.go

@@ -338,6 +338,11 @@ func (c *DefaultClient) DetectVersion(log logging.SimpleLogging, projectDirector
 	}
 
 	constraint, _ := version.NewConstraint(requiredVersionSetting)
+	// Since terraform version 1.8.2, terraform is not a single file download anymore and
+	// Atlantis fails to download version 1.8.2 and higher. So, as a short-term fix,
+	// we need to block any version higher than 1.8.1 until proper solution is implemented.
+	// More details on the issue here - https://github.com/runatlantis/atlantis/issues/4471
+	highestSupportedConstraint, _ := version.NewConstraint("<= 1.8.1")
 	versions := make([]*version.Version, len(tfVersions))
 
 	for i, tfvals := range tfVersions {
@@ -355,7 +360,7 @@ func (c *DefaultClient) DetectVersion(log logging.SimpleLogging, projectDirector
 	sort.Sort(sort.Reverse(version.Collection(versions)))
 
 	for _, element := range versions {
-		if constraint.Check(element) { // Validate a version against a constraint
+		if constraint.Check(element) && highestSupportedConstraint.Check(element) { // Validate a version against a constraint
 			tfversionStr := element.String()
 			if lib.ValidVersionFormat(tfversionStr) { //check if version format is correct
 				tfversion, _ := version.NewVersion(tfversionStr)

server/core/terraform/terraform_client_test.go

@@ -393,6 +393,12 @@ terraform {
 		// cannot use ~> 1.3 or ~> 1.0 since that is a moving target since it will always
 		// resolve to the latest terraform 1.x
 		"~> 1.3.0": "1.3.10",
+		// Since terraform version 1.8.2, terraform is not a single file download anymore and
+		// Atlantis fails to download version 1.8.2 and higher. So, as a short-term fix,
+		// we need to block any version higher than 1.8.1 until proper solution is implemented.
+		// More details on the issue here - https://github.com/runatlantis/atlantis/issues/4471
+		">= 1.3.0": "1.8.1",
+		">= 1.8.2": "",
 	}
 
 	type testCase struct {