1 files changed, 65 insertions, 0 deletions
diff --git a/roles/openshift_health_checker/openshift_checks/disk_availability.py b/roles/openshift_health_checker/openshift_checks/disk_availability.py
new file mode 100644
index 000000000..c2792a0fe
--- /dev/null
+++ b/roles/openshift_health_checker/openshift_checks/disk_availability.py
@@ -0,0 +1,65 @@
+# 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"]
+
+    # Values taken from the official installation documentation:
+    # https://docs.openshift.org/latest/install_config/install/prerequisites.html#system-requirements
+    recommended_disk_space_bytes = {
+        "masters": 40 * 10**9,
+        "nodes": 15 * 10**9,
+        "etcd": 20 * 10**9,
+    }
+
+    @classmethod
+    def is_active(cls, task_vars):
+        """Skip hosts that do not have recommended disk space requirements."""
+        group_names = get_var(task_vars, "group_names", default=[])
+        has_disk_space_recommendation = bool(set(group_names).intersection(cls.recommended_disk_space_bytes))
+        return super(DiskAvailability, cls).is_active(task_vars) and has_disk_space_recommendation
+
+    def run(self, tmp, task_vars):
+        group_names = get_var(task_vars, "group_names")
+        ansible_mounts = get_var(task_vars, "ansible_mounts")
+
+        min_free_bytes = max(self.recommended_disk_space_bytes.get(name, 0) for name in group_names)
+        free_bytes = self.openshift_available_disk(ansible_mounts)
+
+        if free_bytes < min_free_bytes:
+            return {
+                'failed': True,
+                'msg': (
+                    'Available disk space ({:.1f} GB) for the volume containing '
+                    '"/var" is below minimum recommended space ({:.1f} GB)'
+                ).format(float(free_bytes) / 10**9, float(min_free_bytes) / 10**9)
+            }
+
+        return {}
+
+    @staticmethod
+    def openshift_available_disk(ansible_mounts):
+        """Determine the available disk space for an OpenShift installation.
+
+        ansible_mounts should be a list of dicts like the 'setup' Ansible module
+        returns.
+        """
+        # priority list in descending order
+        supported_mnt_paths = ["/var", "/"]
+        available_mnts = {mnt.get("mount"): mnt for mnt in ansible_mounts}
+
+        try:
+            for path in supported_mnt_paths:
+                if path in available_mnts:
+                    return available_mnts[path]["size_available"]
+        except KeyError:
+            pass
+
+        paths = ''.join(sorted(available_mnts)) or 'none'
+        msg = "Unable to determine available disk space. Paths mounted: {}.".format(paths)
+        raise OpenShiftCheckException(msg)