From 5574a5330e358163d5d6ebe64b101a08cde9d666 Mon Sep 17 00:00:00 2001
From: Hardik Dodiya <hardik.dodiya@sap.com>
Date: Wed, 29 Apr 2020 11:29:30 +0530
Subject: [PATCH] Annotate machine-deployment if machine-types are not
 available in cloud

---
 pkg/controller/constants.go  | 20 +++++++++++++++++++
 pkg/controller/deployment.go |  2 +-
 pkg/controller/machine.go    | 37 ++++++++++++++++++++++++++++++++++++
 3 files changed, 58 insertions(+), 1 deletion(-)
 create mode 100644 pkg/controller/constants.go

diff --git a/pkg/controller/constants.go b/pkg/controller/constants.go
new file mode 100644
index 000000000..1ec977a08
--- /dev/null
+++ b/pkg/controller/constants.go
@@ -0,0 +1,20 @@
+package controller
+
+// TODO: Split and move this constants to provider-specific machine-controllers in future.
+const (
+	// MachineTypeNotAvailableAzure is a log message depicting certain machine-types are not available in the azure-cloud.
+	MachineTypeNotAvailableAzure = "The requested size for resource '.*' is currently not available in location '.*' zones '.*' for subscription '.*'"
+
+	// MachineTypeNotAvailableAWS is a log message depicting certain machine-types are not available in the azure-cloud.
+	MachineTypeNotAvailableAWS = "Unsupported: Your requested instance type (.*) is not supported in your requested Availability Zone (.*). Please retry your request by not specifying an Availability Zone or choosing .*"
+
+	// MachineTypeNotAvailableAnnotation annotation is put on machine and node obejcts when cloud-provider is out of certain machine-types.
+	MachineTypeNotAvailableAnnotation = "machine.sapcloud.io/machine-type-not-available"
+)
+
+// Original error messages:
+// AWS:
+// Cloud provider message - Unsupported: Your requested instance type (m5.4xlarge) is not supported in your requested Availability Zone (us-east-1e). Please retry your request by not specifying an Availability Zone or choosing us-east-1b, us-east-1d, us-east-1a, us-east-1f, us-east-1c.
+
+// Azure:
+// The requested size for resource '/subscriptions/123c2-4-1234/resourceGroups/shoot--12-12/providers/Microsoft.Compute/virtualMac2321321312/1234-nz7vw' is currently not available in location 'westeurope' zones '1' for subscription '2c3d1231-s21321321-8c04-2711234'.
diff --git a/pkg/controller/deployment.go b/pkg/controller/deployment.go
index 05fb231c1..c89dd3ad6 100644
--- a/pkg/controller/deployment.go
+++ b/pkg/controller/deployment.go
@@ -302,7 +302,7 @@ func (dc *controller) getMachineDeploymentForMachine(machine *v1alpha1.Machine)
 		// No controller owns this Machine.
 		return nil
 	}
-	if controllerRef.Kind != "MachineDeployment" { //TODO: Remove hardcoded string
+	if controllerRef.Kind != "MachineSet" { //TODO: Remove hardcoded string
 		// Not a Machine owned by a machine set.
 		return nil
 	}
diff --git a/pkg/controller/machine.go b/pkg/controller/machine.go
index 09a36d6ae..777719349 100644
--- a/pkg/controller/machine.go
+++ b/pkg/controller/machine.go
@@ -22,6 +22,7 @@ import (
 	"errors"
 	"fmt"
 	"math"
+	"regexp"
 	"strings"
 	"time"
 
@@ -428,6 +429,27 @@ func (c *controller) machineCreate(machine *v1alpha1.Machine, driver driver.Driv
 			klog.Warning(err)
 		}
 
+		// Check if the creation-error logs contain the specific pattern, and annotate the machine-deployment if found.
+		contains, _ := c.containsSpecialPattern(err.Error(), MachineTypeNotAvailableAzure, MachineTypeNotAvailableAWS)
+
+		if contains {
+			md := c.getMachineDeploymentForMachine(machine)
+			if md != nil {
+				mdCopy := md.DeepCopy()
+				annotations := mdCopy.Spec.Template.Spec.NodeTemplateSpec.Annotations
+				if annotations == nil {
+					annotations = make(map[string]string)
+				}
+				annotations[MachineTypeNotAvailableAnnotation] = "True"
+				mdCopy.Spec.Template.Spec.NodeTemplateSpec.Annotations = annotations
+
+				_, errUpdate := c.controlMachineClient.MachineDeployments(machine.Namespace).Update(mdCopy)
+				if errUpdate != nil {
+					klog.Errorf("Error updating the machine-deployment %+v", errUpdate)
+				}
+			}
+		}
+
 		return err
 	}
 	klog.V(2).Infof("Created/Adopted machine: %q, MachineID: %s", machine.Name, actualProviderID)
@@ -1025,3 +1047,18 @@ func decodeMachineID(id string) string {
 	splitProviderID := strings.Split(id, "/")
 	return splitProviderID[len(splitProviderID)-1]
 }
+
+// containsSpecialPattern checks if the errorString contains any of the patterns
+func (c *controller) containsSpecialPattern(errorString string, patterns ...string) (bool, error) {
+	for _, pattern := range patterns {
+		matched, err := regexp.MatchString(pattern, errorString)
+		if err != nil {
+			klog.Errorf("Error matching the string %+v", err)
+			return false, err
+		}
+		if matched {
+			return true, nil
+		}
+	}
+	return false, nil
+}