#
k8s_openapi/v1_35/api/core/v1/
topology_spread_constraint.rs

    1// Generated from definition io.k8s.api.core.v1.TopologySpreadConstraint
    2
    3/// TopologySpreadConstraint specifies how to spread matching pods among the given topology.
    4#[derive(Clone, Debug, Default, PartialEq)]
    5pub struct TopologySpreadConstraint {
    6    /// LabelSelector is used to find matching pods. Pods that match this label selector are counted to determine the number of pods in their corresponding topology domain.
    7    pub label_selector: Option<crate::apimachinery::pkg::apis::meta::v1::LabelSelector>,
    8
    9    /// MatchLabelKeys is a set of pod label keys to select the pods over which spreading will be calculated. The keys are used to lookup values from the incoming pod labels, those key-value labels are ANDed with labelSelector to select the group of existing pods over which spreading will be calculated for the incoming pod. The same key is forbidden to exist in both MatchLabelKeys and LabelSelector. MatchLabelKeys cannot be set when LabelSelector isn't set. Keys that don't exist in the incoming pod labels will be ignored. A null or empty list means only match against labelSelector.
    10    ///
    11    /// This is a beta field and requires the MatchLabelKeysInPodTopologySpread feature gate to be enabled (enabled by default).
    12    pub match_label_keys: Option<std::vec::Vec<std::string::String>>,
    13
    14    /// MaxSkew describes the degree to which pods may be unevenly distributed. When `whenUnsatisfiable=DoNotSchedule`, it is the maximum permitted difference between the number of matching pods in the target topology and the global minimum. The global minimum is the minimum number of matching pods in an eligible domain or zero if the number of eligible domains is less than MinDomains. For example, in a 3-zone cluster, MaxSkew is set to 1, and pods with the same labelSelector spread as 2/2/1: In this case, the global minimum is 1. | zone1 | zone2 | zone3 | |  P P  |  P P  |   P   | - if MaxSkew is 1, incoming pod can only be scheduled to zone3 to become 2/2/2; scheduling it onto zone1(zone2) would make the ActualSkew(3-1) on zone1(zone2) violate MaxSkew(1). - if MaxSkew is 2, incoming pod can be scheduled onto any zone. When `whenUnsatisfiable=ScheduleAnyway`, it is used to give higher precedence to topologies that satisfy it. It's a required field. Default value is 1 and 0 is not allowed.
    15    pub max_skew: i32,
    16
    17    /// MinDomains indicates a minimum number of eligible domains. When the number of eligible domains with matching topology keys is less than minDomains, Pod Topology Spread treats "global minimum" as 0, and then the calculation of Skew is performed. And when the number of eligible domains with matching topology keys equals or greater than minDomains, this value has no effect on scheduling. As a result, when the number of eligible domains is less than minDomains, scheduler won't schedule more than maxSkew Pods to those domains. If value is nil, the constraint behaves as if MinDomains is equal to 1. Valid values are integers greater than 0. When value is not nil, WhenUnsatisfiable must be DoNotSchedule.
    18    ///
    19    /// For example, in a 3-zone cluster, MaxSkew is set to 2, MinDomains is set to 5 and pods with the same labelSelector spread as 2/2/2: | zone1 | zone2 | zone3 | |  P P  |  P P  |  P P  | The number of domains is less than 5(MinDomains), so "global minimum" is treated as 0. In this situation, new pod with the same labelSelector cannot be scheduled, because computed skew will be 3(3 - 0) if new Pod is scheduled to any of the three zones, it will violate MaxSkew.
    20    pub min_domains: Option<i32>,
    21
    22    /// NodeAffinityPolicy indicates how we will treat Pod's nodeAffinity/nodeSelector when calculating pod topology spread skew. Options are: - Honor: only nodes matching nodeAffinity/nodeSelector are included in the calculations. - Ignore: nodeAffinity/nodeSelector are ignored. All nodes are included in the calculations.
    23    ///
    24    /// If this value is nil, the behavior is equivalent to the Honor policy.
    25    pub node_affinity_policy: Option<std::string::String>,
    26
    27    /// NodeTaintsPolicy indicates how we will treat node taints when calculating pod topology spread skew. Options are: - Honor: nodes without taints, along with tainted nodes for which the incoming pod has a toleration, are included. - Ignore: node taints are ignored. All nodes are included.
    28    ///
    29    /// If this value is nil, the behavior is equivalent to the Ignore policy.
    30    pub node_taints_policy: Option<std::string::String>,
    31
    32    /// TopologyKey is the key of node labels. Nodes that have a label with this key and identical values are considered to be in the same topology. We consider each \<key, value\> as a "bucket", and try to put balanced number of pods into each bucket. We define a domain as a particular instance of a topology. Also, we define an eligible domain as a domain whose nodes meet the requirements of nodeAffinityPolicy and nodeTaintsPolicy. e.g. If TopologyKey is "kubernetes.io/hostname", each Node is a domain of that topology. And, if TopologyKey is "topology.kubernetes.io/zone", each zone is a domain of that topology. It's a required field.
    33    pub topology_key: std::string::String,
    34
    35    /// WhenUnsatisfiable indicates how to deal with a pod if it doesn't satisfy the spread constraint. - DoNotSchedule (default) tells the scheduler not to schedule it. - ScheduleAnyway tells the scheduler to schedule the pod in any location,
    36    ///   but giving higher precedence to topologies that would help reduce the
    37    ///   skew.
    38    /// A constraint is considered "Unsatisfiable" for an incoming pod if and only if every possible node assignment for that pod would violate "MaxSkew" on some topology. For example, in a 3-zone cluster, MaxSkew is set to 1, and pods with the same labelSelector spread as 3/1/1: | zone1 | zone2 | zone3 | | P P P |   P   |   P   | If WhenUnsatisfiable is set to DoNotSchedule, incoming pod can only be scheduled to zone2(zone3) to become 3/2/1(3/1/2) as ActualSkew(2-1) on zone2(zone3) satisfies MaxSkew(1). In other words, the cluster can still be imbalanced, but scheduler won't make it *more* imbalanced. It's a required field.
    39    pub when_unsatisfiable: std::string::String,
    40}
    41
    42impl crate::DeepMerge for TopologySpreadConstraint {
    43    fn merge_from(&mut self, other: Self) {
    44        crate::DeepMerge::merge_from(&mut self.label_selector, other.label_selector);
    45        crate::merge_strategies::list::atomic(&mut self.match_label_keys, other.match_label_keys);
    46        crate::DeepMerge::merge_from(&mut self.max_skew, other.max_skew);
    47        crate::DeepMerge::merge_from(&mut self.min_domains, other.min_domains);
    48        crate::DeepMerge::merge_from(&mut self.node_affinity_policy, other.node_affinity_policy);
    49        crate::DeepMerge::merge_from(&mut self.node_taints_policy, other.node_taints_policy);
    50        crate::DeepMerge::merge_from(&mut self.topology_key, other.topology_key);
    51        crate::DeepMerge::merge_from(&mut self.when_unsatisfiable, other.when_unsatisfiable);
    52    }
    53}
    54
    55impl<'de> crate::serde::Deserialize<'de> for TopologySpreadConstraint {
    56    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> where D: crate::serde::Deserializer<'de> {
    57        #[allow(non_camel_case_types)]
    58        enum Field {
    59            Key_label_selector,
    60            Key_match_label_keys,
    61            Key_max_skew,
    62            Key_min_domains,
    63            Key_node_affinity_policy,
    64            Key_node_taints_policy,
    65            Key_topology_key,
    66            Key_when_unsatisfiable,
    67            Other,
    68        }
    69
    70        impl<'de> crate::serde::Deserialize<'de> for Field {
    71            fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> where D: crate::serde::Deserializer<'de> {
    72                struct Visitor;
    73
    74                impl crate::serde::de::Visitor<'_> for Visitor {
    75                    type Value = Field;
    76
    77                    fn expecting(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
    78                        f.write_str("field identifier")
    79                    }
    80
    81                    fn visit_str<E>(self, v: &str) -> Result<Self::Value, E> where E: crate::serde::de::Error {
    82                        Ok(match v {
    83                            "labelSelector" => Field::Key_label_selector,
    84                            "matchLabelKeys" => Field::Key_match_label_keys,
    85                            "maxSkew" => Field::Key_max_skew,
    86                            "minDomains" => Field::Key_min_domains,
    87                            "nodeAffinityPolicy" => Field::Key_node_affinity_policy,
    88                            "nodeTaintsPolicy" => Field::Key_node_taints_policy,
    89                            "topologyKey" => Field::Key_topology_key,
    90                            "whenUnsatisfiable" => Field::Key_when_unsatisfiable,
    91                            _ => Field::Other,
    92                        })
    93                    }
    94                }
    95
    96                deserializer.deserialize_identifier(Visitor)
    97            }
    98        }
    99
    100        struct Visitor;
    101
    102        impl<'de> crate::serde::de::Visitor<'de> for Visitor {
    103            type Value = TopologySpreadConstraint;
    104
    105            fn expecting(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
    106                f.write_str("TopologySpreadConstraint")
    107            }
    108
    109            fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error> where A: crate::serde::de::MapAccess<'de> {
    110                let mut value_label_selector: Option<crate::apimachinery::pkg::apis::meta::v1::LabelSelector> = None;
    111                let mut value_match_label_keys: Option<std::vec::Vec<std::string::String>> = None;
    112                let mut value_max_skew: Option<i32> = None;
    113                let mut value_min_domains: Option<i32> = None;
    114                let mut value_node_affinity_policy: Option<std::string::String> = None;
    115                let mut value_node_taints_policy: Option<std::string::String> = None;
    116                let mut value_topology_key: Option<std::string::String> = None;
    117                let mut value_when_unsatisfiable: Option<std::string::String> = None;
    118
    119                while let Some(key) = crate::serde::de::MapAccess::next_key::<Field>(&mut map)? {
    120                    match key {
    121                        Field::Key_label_selector => value_label_selector = crate::serde::de::MapAccess::next_value(&mut map)?,
    122                        Field::Key_match_label_keys => value_match_label_keys = crate::serde::de::MapAccess::next_value(&mut map)?,
    123                        Field::Key_max_skew => value_max_skew = crate::serde::de::MapAccess::next_value(&mut map)?,
    124                        Field::Key_min_domains => value_min_domains = crate::serde::de::MapAccess::next_value(&mut map)?,
    125                        Field::Key_node_affinity_policy => value_node_affinity_policy = crate::serde::de::MapAccess::next_value(&mut map)?,
    126                        Field::Key_node_taints_policy => value_node_taints_policy = crate::serde::de::MapAccess::next_value(&mut map)?,
    127                        Field::Key_topology_key => value_topology_key = crate::serde::de::MapAccess::next_value(&mut map)?,
    128                        Field::Key_when_unsatisfiable => value_when_unsatisfiable = crate::serde::de::MapAccess::next_value(&mut map)?,
    129                        Field::Other => { let _: crate::serde::de::IgnoredAny = crate::serde::de::MapAccess::next_value(&mut map)?; },
    130                    }
    131                }
    132
    133                Ok(TopologySpreadConstraint {
    134                    label_selector: value_label_selector,
    135                    match_label_keys: value_match_label_keys,
    136                    max_skew: value_max_skew.unwrap_or_default(),
    137                    min_domains: value_min_domains,
    138                    node_affinity_policy: value_node_affinity_policy,
    139                    node_taints_policy: value_node_taints_policy,
    140                    topology_key: value_topology_key.unwrap_or_default(),
    141                    when_unsatisfiable: value_when_unsatisfiable.unwrap_or_default(),
    142                })
    143            }
    144        }
    145
    146        deserializer.deserialize_struct(
    147            "TopologySpreadConstraint",
    148            &[
    149                "labelSelector",
    150                "matchLabelKeys",
    151                "maxSkew",
    152                "minDomains",
    153                "nodeAffinityPolicy",
    154                "nodeTaintsPolicy",
    155                "topologyKey",
    156                "whenUnsatisfiable",
    157            ],
    158            Visitor,
    159        )
    160    }
    161}
    162
    163impl crate::serde::Serialize for TopologySpreadConstraint {
    164    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> where S: crate::serde::Serializer {
    165        let mut state = serializer.serialize_struct(
    166            "TopologySpreadConstraint",
    167            3 +
    168            self.label_selector.as_ref().map_or(0, |_| 1) +
    169            self.match_label_keys.as_ref().map_or(0, |_| 1) +
    170            self.min_domains.as_ref().map_or(0, |_| 1) +
    171            self.node_affinity_policy.as_ref().map_or(0, |_| 1) +
    172            self.node_taints_policy.as_ref().map_or(0, |_| 1),
    173        )?;
    174        if let Some(value) = &self.label_selector {
    175            crate::serde::ser::SerializeStruct::serialize_field(&mut state, "labelSelector", value)?;
    176        }
    177        if let Some(value) = &self.match_label_keys {
    178            crate::serde::ser::SerializeStruct::serialize_field(&mut state, "matchLabelKeys", value)?;
    179        }
    180        crate::serde::ser::SerializeStruct::serialize_field(&mut state, "maxSkew", &self.max_skew)?;
    181        if let Some(value) = &self.min_domains {
    182            crate::serde::ser::SerializeStruct::serialize_field(&mut state, "minDomains", value)?;
    183        }
    184        if let Some(value) = &self.node_affinity_policy {
    185            crate::serde::ser::SerializeStruct::serialize_field(&mut state, "nodeAffinityPolicy", value)?;
    186        }
    187        if let Some(value) = &self.node_taints_policy {
    188            crate::serde::ser::SerializeStruct::serialize_field(&mut state, "nodeTaintsPolicy", value)?;
    189        }
    190        crate::serde::ser::SerializeStruct::serialize_field(&mut state, "topologyKey", &self.topology_key)?;
    191        crate::serde::ser::SerializeStruct::serialize_field(&mut state, "whenUnsatisfiable", &self.when_unsatisfiable)?;
    192        crate::serde::ser::SerializeStruct::end(state)
    193    }
    194}
    195
    196#[cfg(feature = "schemars")]
    197impl crate::schemars::JsonSchema for TopologySpreadConstraint {
    198    fn schema_name() -> std::borrow::Cow<'static, str> {
    199        "io.k8s.api.core.v1.TopologySpreadConstraint".into()
    200    }
    201
    202    fn json_schema(__gen: &mut crate::schemars::SchemaGenerator) -> crate::schemars::Schema {
    203        crate::schemars::json_schema!({
    204            "description": "TopologySpreadConstraint specifies how to spread matching pods among the given topology.",
    205            "type": "object",
    206            "properties": {
    207                "labelSelector": ({
    208                    let mut schema_obj = __gen.subschema_for::<crate::apimachinery::pkg::apis::meta::v1::LabelSelector>();
    209                    schema_obj.ensure_object().insert("description".into(), "LabelSelector is used to find matching pods. Pods that match this label selector are counted to determine the number of pods in their corresponding topology domain.".into());
    210                    schema_obj
    211                }),
    212                "matchLabelKeys": {
    213                    "description": "MatchLabelKeys is a set of pod label keys to select the pods over which spreading will be calculated. The keys are used to lookup values from the incoming pod labels, those key-value labels are ANDed with labelSelector to select the group of existing pods over which spreading will be calculated for the incoming pod. The same key is forbidden to exist in both MatchLabelKeys and LabelSelector. MatchLabelKeys cannot be set when LabelSelector isn't set. Keys that don't exist in the incoming pod labels will be ignored. A null or empty list means only match against labelSelector.\n\nThis is a beta field and requires the MatchLabelKeysInPodTopologySpread feature gate to be enabled (enabled by default).",
    214                    "type": "array",
    215                    "items": {
    216                        "type": "string",
    217                    },
    218                },
    219                "maxSkew": {
    220                    "description": "MaxSkew describes the degree to which pods may be unevenly distributed. When `whenUnsatisfiable=DoNotSchedule`, it is the maximum permitted difference between the number of matching pods in the target topology and the global minimum. The global minimum is the minimum number of matching pods in an eligible domain or zero if the number of eligible domains is less than MinDomains. For example, in a 3-zone cluster, MaxSkew is set to 1, and pods with the same labelSelector spread as 2/2/1: In this case, the global minimum is 1. | zone1 | zone2 | zone3 | |  P P  |  P P  |   P   | - if MaxSkew is 1, incoming pod can only be scheduled to zone3 to become 2/2/2; scheduling it onto zone1(zone2) would make the ActualSkew(3-1) on zone1(zone2) violate MaxSkew(1). - if MaxSkew is 2, incoming pod can be scheduled onto any zone. When `whenUnsatisfiable=ScheduleAnyway`, it is used to give higher precedence to topologies that satisfy it. It's a required field. Default value is 1 and 0 is not allowed.",
    221                    "type": "integer",
    222                    "format": "int32",
    223                },
    224                "minDomains": {
    225                    "description": "MinDomains indicates a minimum number of eligible domains. When the number of eligible domains with matching topology keys is less than minDomains, Pod Topology Spread treats \"global minimum\" as 0, and then the calculation of Skew is performed. And when the number of eligible domains with matching topology keys equals or greater than minDomains, this value has no effect on scheduling. As a result, when the number of eligible domains is less than minDomains, scheduler won't schedule more than maxSkew Pods to those domains. If value is nil, the constraint behaves as if MinDomains is equal to 1. Valid values are integers greater than 0. When value is not nil, WhenUnsatisfiable must be DoNotSchedule.\n\nFor example, in a 3-zone cluster, MaxSkew is set to 2, MinDomains is set to 5 and pods with the same labelSelector spread as 2/2/2: | zone1 | zone2 | zone3 | |  P P  |  P P  |  P P  | The number of domains is less than 5(MinDomains), so \"global minimum\" is treated as 0. In this situation, new pod with the same labelSelector cannot be scheduled, because computed skew will be 3(3 - 0) if new Pod is scheduled to any of the three zones, it will violate MaxSkew.",
    226                    "type": "integer",
    227                    "format": "int32",
    228                },
    229                "nodeAffinityPolicy": {
    230                    "description": "NodeAffinityPolicy indicates how we will treat Pod's nodeAffinity/nodeSelector when calculating pod topology spread skew. Options are: - Honor: only nodes matching nodeAffinity/nodeSelector are included in the calculations. - Ignore: nodeAffinity/nodeSelector are ignored. All nodes are included in the calculations.\n\nIf this value is nil, the behavior is equivalent to the Honor policy.",
    231                    "type": "string",
    232                },
    233                "nodeTaintsPolicy": {
    234                    "description": "NodeTaintsPolicy indicates how we will treat node taints when calculating pod topology spread skew. Options are: - Honor: nodes without taints, along with tainted nodes for which the incoming pod has a toleration, are included. - Ignore: node taints are ignored. All nodes are included.\n\nIf this value is nil, the behavior is equivalent to the Ignore policy.",
    235                    "type": "string",
    236                },
    237                "topologyKey": {
    238                    "description": "TopologyKey is the key of node labels. Nodes that have a label with this key and identical values are considered to be in the same topology. We consider each <key, value> as a \"bucket\", and try to put balanced number of pods into each bucket. We define a domain as a particular instance of a topology. Also, we define an eligible domain as a domain whose nodes meet the requirements of nodeAffinityPolicy and nodeTaintsPolicy. e.g. If TopologyKey is \"kubernetes.io/hostname\", each Node is a domain of that topology. And, if TopologyKey is \"topology.kubernetes.io/zone\", each zone is a domain of that topology. It's a required field.",
    239                    "type": "string",
    240                },
    241                "whenUnsatisfiable": {
    242                    "description": "WhenUnsatisfiable indicates how to deal with a pod if it doesn't satisfy the spread constraint. - DoNotSchedule (default) tells the scheduler not to schedule it. - ScheduleAnyway tells the scheduler to schedule the pod in any location,\n  but giving higher precedence to topologies that would help reduce the\n  skew.\nA constraint is considered \"Unsatisfiable\" for an incoming pod if and only if every possible node assignment for that pod would violate \"MaxSkew\" on some topology. For example, in a 3-zone cluster, MaxSkew is set to 1, and pods with the same labelSelector spread as 3/1/1: | zone1 | zone2 | zone3 | | P P P |   P   |   P   | If WhenUnsatisfiable is set to DoNotSchedule, incoming pod can only be scheduled to zone2(zone3) to become 3/2/1(3/1/2) as ActualSkew(2-1) on zone2(zone3) satisfies MaxSkew(1). In other words, the cluster can still be imbalanced, but scheduler won't make it *more* imbalanced. It's a required field.",
    243                    "type": "string",
    244                },
    245            },
    246            "required": [
    247                "maxSkew",
    248                "topologyKey",
    249                "whenUnsatisfiable",
    250            ],
    251        })
    252    }
    253}