add ram and storage preflight check

roles/openshift_health_checker/openshift_checks/disk_availability.py

@@ -0,0 +1,73 @@
+# pylint: disable=missing-docstring
+from openshift_checks import OpenShiftCheck, OpenShiftCheckException, get_var
+from openshift_checks.mixins import NotContainerizedMixin
+
+
+class DiskAvailability(NotContainerizedMixin, OpenShiftCheck):
+    """Check that recommended disk space is available before a first-time install."""
+
+    name = "disk_availability"
+    tags = ["preflight"]
+
+    # all values are base-10 as they are taken, as is, from
+    # the latest requirements for an OpenShift installation
+    # https://docs.openshift.org/latest/install_config/install/prerequisites.html#system-requirements
+    recommended_diskspace = {
+        "nodes": 15 * 10 ** 9,
+        "masters": 40 * 10 ** 9,
+        "etcd": 20 * 10 ** 9,
+    }
+
+    def run(self, tmp, task_vars):
+        ansible_mounts = get_var(task_vars, "ansible_mounts")
+        self.recommended_diskspace["nodes"] = get_var(task_vars,
+                                                      "min_recommended_diskspace_node",
+                                                      default=self.recommended_diskspace["nodes"])
+        self.recommended_diskspace["masters"] = get_var(task_vars,
+                                                        "min_recommended_diskspace_master",
+                                                        default=self.recommended_diskspace["masters"])
+        self.recommended_diskspace["etcd"] = get_var(task_vars,
+                                                     "min_recommended_diskspace_etcd",
+                                                     default=self.recommended_diskspace["etcd"])
+
+        failed, msg = self.volume_check(ansible_mounts, task_vars)
+        return {"failed": failed, "msg": msg}
+
+    def volume_check(self, ansible_mounts, task_vars):
+        group_names = get_var(task_vars, "group_names", default=[])
+
+        if not set(self.recommended_diskspace).intersection(group_names):
+            msg = "Unable to determine recommended volume size for group_name {group_name}"
+            raise OpenShiftCheckException(msg.format(group_name=group_names))
+
+        recommended_diskspace_bytes = max(self.recommended_diskspace.get(group, 0) for group in group_names)
+        openshift_diskfree_bytes = self.get_openshift_disk_availability(ansible_mounts)
+
+        if openshift_diskfree_bytes < recommended_diskspace_bytes:
+            msg = ("Available disk space ({diskfree} GB) for the volume containing \"/var\" is "
+                   "below recommended storage. Minimum required disk space: {recommended} GB")
+            return True, msg.format(diskfree=self.to_gigabytes(openshift_diskfree_bytes),
+                                    recommended=self.to_gigabytes(recommended_diskspace_bytes))
+
+        return False, ""
+
+    @staticmethod
+    def get_openshift_disk_availability(ansible_mounts):
+        """Iterates through a map of mounted volumes to determine space remaining on the OpenShift volume"""
+        if not ansible_mounts:
+            msg = "Unable to determine existing volume mounts from ansible_mounts"
+            raise OpenShiftCheckException(msg)
+
+        # priority list in descending order
+        supported_mnt_paths = ["/var", "/"]
+        available_mnts = {mnt.get("mount"): mnt for mnt in ansible_mounts}
+
+        for path in supported_mnt_paths:
+            if path in available_mnts:
+                return available_mnts[path].get("size_available")
+
+        return 0
+
+    @staticmethod
+    def to_gigabytes(total_bytes):
+        return total_bytes / 10**9

roles/openshift_health_checker/openshift_checks/memory_availability.py

@@ -0,0 +1,35 @@
+# pylint: disable=missing-docstring
+from openshift_checks import OpenShiftCheck, get_var
+
+
+class MemoryAvailability(OpenShiftCheck):
+    """Check that recommended memory is available."""
+
+    name = "memory_availability"
+    tags = ["preflight"]
+
+    recommended_memory_mb = {
+        "nodes": 8 * 1000,
+        "masters": 16 * 1000,
+        "etcd": 10 * 1000,
+    }
+
+    @classmethod
+    def is_active(cls, task_vars):
+        """Skip hosts that do not have recommended memory space requirements."""
+        group_names = get_var(task_vars, "group_names", default=[])
+        has_mem_space_recommendation = bool(set(group_names).intersection(cls.recommended_memory_mb))
+        return super(MemoryAvailability, cls).is_active(task_vars) and has_mem_space_recommendation
+
+    def run(self, tmp, task_vars):
+        group_names = get_var(task_vars, "group_names", default=[])
+        total_memory = get_var(task_vars, "ansible_memtotal_mb")
+
+        recommended_memory_mb = max(self.recommended_memory_mb.get(group, 0) for group in group_names)
+
+        if total_memory < recommended_memory_mb:
+            msg = ("Available memory ({available} MB) below recommended storage. "
+                   "Minimum required memory: {recommended} MB")
+            return {"failed": True, "msg": msg.format(available=total_memory, recommended=recommended_memory_mb)}
+
+        return {"changed": False}