Documentation ¶
Index ¶
- Variables
- func KeyToDefaultDeleteParentPaths(key Key) ([]string, error)
- func KeyToDefaultDeletePath(key Key) (string, error)
- func KeyToDefaultPath(key Key) (string, error)
- func ListOptionsToDefaultPathRoot(listOptions ListInterface) string
- func ParseValue(key Key, rawData []byte) (interface{}, error)
- func SerializeValue(d *KVPair) ([]byte, error)
- type ActiveStatusReportKey
- type ActiveStatusReportListOptions
- type AllocationAttribute
- type AllocationBlock
- type BGPNode
- type BGPNodeKey
- type BGPPeer
- type BlockAffinityKey
- type BlockAffinityListOptions
- type BlockKey
- type BlockListOptions
- type GlobalBGPConfigKey
- type GlobalBGPConfigListOptions
- type GlobalBGPPeerKey
- type GlobalBGPPeerListOptions
- type GlobalConfigKey
- type GlobalConfigListOptions
- type HostConfigKey
- type HostConfigListOptions
- type HostEndpoint
- type HostEndpointKey
- type HostEndpointListOptions
- type HostEndpointStatus
- type HostEndpointStatusKey
- type HostEndpointStatusListOptions
- type HostIPKey
- type HostMetadata
- type HostMetadataKey
- type HostMetadataListOptions
- type IPAMConfig
- type IPAMConfigKey
- type IPAMHandle
- type IPAMHandleKey
- type IPAMHandleListOptions
- type IPAMHost
- type IPAMHostKey
- type IPNAT
- type IPPool
- type IPPoolKey
- type IPPoolListOptions
- type KVPair
- type Key
- type LastStatusReportKey
- type LastStatusReportListOptions
- type ListInterface
- type Node
- type NodeBGPConfigKey
- type NodeBGPConfigListOptions
- type NodeBGPPeerKey
- type NodeBGPPeerListOptions
- type NodeKey
- type NodeListOptions
- type OrchRef
- type OrchRefKey
- type OrchRefListOptions
- type Policy
- type PolicyKey
- type PolicyListOptions
- type Profile
- type ProfileKey
- type ProfileLabelsKey
- type ProfileListOptions
- type ProfileRules
- type ProfileRulesKey
- type ProfileTagsKey
- type ReadyFlagKey
- type Rule
- type StatusReport
- type WorkloadEndpoint
- type WorkloadEndpointKey
- type WorkloadEndpointListOptions
- type WorkloadEndpointStatus
- type WorkloadEndpointStatusKey
- type WorkloadEndpointStatusListOptions
- Bugs
Constants ¶
This section is empty.
Variables ¶
var ( // The BlockAffinity is stored as a raw string type. It currently does // not contain any information since all required information is stored // in the key (hostname and block CIDR). If we end up needing to store // data in the BlockAffinity then care will need to be taken to ensure // existing versions of the value (an empty string) can be successfully // unmarshalled. // - The Python version of IPAM wrote an empty string, but can handle // any value written into the data. // - The original golang port of IPAM wrote "{}" into the data (the JSON // value for an empty dict). It was unable to handle reading of an // empty string written out by the Python IPAM. // - The current version of the golang port now has the BlockAffinity // as a raw-string type so that it can handle reading in any value. // We write in a fixed value of "{}" so that we are compatible with // both the Python and the original golang port. BlockAffinityValue = "{}" )
Functions ¶
func KeyToDefaultDeleteParentPaths ¶
KeyToDefaultDeleteParentPaths returns a slice of '/'-delimited paths which are used to delete parent entries that may be auto-created by directory-based KV stores (e.g. etcd v2). These paths should also be removed provided they have no more child entries.
The list of parent paths is ordered, and directories should be removed in the order supplied in the slice and only if the directory is empty.
For example,
KeyToDefaultDeletePaths(WorkloadEndpointKey{ Nodename: "h", OrchestratorID: "o", WorkloadID: "w", EndpointID: "e", })
returns
["/calico/v1/host/h/workload/o/w/endpoint",
"/calico/v1/host/h/workload/o/w"]
indicating that these paths should also be deleted when they are empty. In this example it is equivalent to deleting the workload when there are no more endpoints in the workload.
func KeyToDefaultDeletePath ¶
KeyToDefaultDeletePath converts one of the Keys from this package into a unique '/'-delimited path, which is suitable for use as the key when (recursively) deleting the value from a hierarchical (i.e. one with directories and leaves) key/value datastore such as etcd v2.
KeyToDefaultDeletePath returns a different path to KeyToDefaultPath when it is a passed a Key that represents a non-leaf which, for example, has its own metadata but also contains other resource types as children.
KeyToDefaultDeletePath returns the common prefix of the non-leaf key and its children so that a recursive delete of that key would delete the object itself and any children it has.
func KeyToDefaultPath ¶
KeyToDefaultPath converts one of the Keys from this package into a unique '/'-delimited path, which is suitable for use as the key when storing the value in a hierarchical (i.e. one with directories and leaves) key/value datastore such as etcd v2.
Each unique key returns a unique path.
Keys with a hierarchical relationship share a common prefix. However, in order to support datastores that do not support storing data at non-leaf nodes in the hierarchy (such as etcd v2), the path returned for a "parent" key, is not a direct ancestor of its children.
func ListOptionsToDefaultPathRoot ¶
func ListOptionsToDefaultPathRoot(listOptions ListInterface) string
ListOptionsToDefaultPathRoot converts list options struct into a common-prefix path suitable for querying a datastore that uses the paths returned by KeyToDefaultPath.
func ParseValue ¶
ParseValue parses the default JSON representation of our data into one of our value structs, according to the type of key. I.e. if passed a PolicyKey as the first parameter, it will try to parse rawData into a Policy struct.
Types ¶
type ActiveStatusReportKey ¶
type ActiveStatusReportKey struct {
Hostname string `json:"-" validate:"required,hostname"`
}
func (ActiveStatusReportKey) String ¶
func (key ActiveStatusReportKey) String() string
type ActiveStatusReportListOptions ¶
type ActiveStatusReportListOptions struct {
Hostname string
}
func (ActiveStatusReportListOptions) KeyFromDefaultPath ¶
func (options ActiveStatusReportListOptions) KeyFromDefaultPath(ekey string) Key
type AllocationAttribute ¶
type AllocationBlock ¶
type AllocationBlock struct { CIDR net.IPNet `json:"cidr"` Affinity *string `json:"affinity"` StrictAffinity bool `json:"strictAffinity"` Allocations []*int `json:"allocations"` Unallocated []int `json:"unallocated"` Attributes []AllocationAttribute `json:"attributes"` // HostAffinity is deprecated in favor of Affinity. // This is only to keep compatiblity with existing deployments. // The data format should be `Affinity: host:hostname` (not `hostAffinity: hostname`). HostAffinity *string `json:"hostAffinity,omitempty"` }
type BGPNode ¶ added in v1.7.2
type BGPNode struct { }
type BGPNodeKey ¶ added in v1.7.2
type BGPNodeKey struct {
Host string
}
func (BGPNodeKey) String ¶ added in v1.7.2
func (key BGPNodeKey) String() string
type BGPPeer ¶
type BGPPeer struct { // PeerIP is the IP address of the BGP peer. PeerIP net.IP `json:"ip"` // ASNum is the AS number of the peer. Note that we write out the // value as a string in to the backend, because confd templating // converts large uints to float e notation which breaks the BIRD // configuration. ASNum numorstring.ASNumber `json:"as_num,string"` }
type BlockAffinityKey ¶
type BlockAffinityKey struct { CIDR net.IPNet `json:"-" validate:"required,name"` Host string `json:"-"` }
func (BlockAffinityKey) String ¶ added in v1.0.1
func (key BlockAffinityKey) String() string
type BlockAffinityListOptions ¶
func (BlockAffinityListOptions) KeyFromDefaultPath ¶
func (options BlockAffinityListOptions) KeyFromDefaultPath(path string) Key
type BlockKey ¶
type BlockListOptions ¶
type BlockListOptions struct {
IPVersion int `json:"-"`
}
func (BlockListOptions) KeyFromDefaultPath ¶
func (options BlockListOptions) KeyFromDefaultPath(path string) Key
type GlobalBGPConfigKey ¶
type GlobalBGPConfigKey struct { // The name of the global BGP config key. Name string `json:"-" validate:"required,name"` }
func (GlobalBGPConfigKey) String ¶
func (key GlobalBGPConfigKey) String() string
type GlobalBGPConfigListOptions ¶ added in v1.5.0
type GlobalBGPConfigListOptions struct {
Name string
}
func (GlobalBGPConfigListOptions) KeyFromDefaultPath ¶ added in v1.5.0
func (options GlobalBGPConfigListOptions) KeyFromDefaultPath(path string) Key
type GlobalBGPPeerKey ¶ added in v1.5.0
func (GlobalBGPPeerKey) String ¶ added in v1.5.0
func (key GlobalBGPPeerKey) String() string
type GlobalBGPPeerListOptions ¶ added in v1.5.0
func (GlobalBGPPeerListOptions) KeyFromDefaultPath ¶ added in v1.5.0
func (options GlobalBGPPeerListOptions) KeyFromDefaultPath(path string) Key
type GlobalConfigKey ¶
type GlobalConfigKey struct {
Name string `json:"-" validate:"required,name"`
}
func (GlobalConfigKey) String ¶
func (key GlobalConfigKey) String() string
type GlobalConfigListOptions ¶
type GlobalConfigListOptions struct {
Name string
}
func (GlobalConfigListOptions) KeyFromDefaultPath ¶
func (options GlobalConfigListOptions) KeyFromDefaultPath(path string) Key
type HostConfigKey ¶
type HostConfigKey struct { Hostname string `json:"-" validate:"required,name"` Name string `json:"-" validate:"required,name"` }
func (HostConfigKey) String ¶
func (key HostConfigKey) String() string
type HostConfigListOptions ¶
func (HostConfigListOptions) KeyFromDefaultPath ¶
func (options HostConfigListOptions) KeyFromDefaultPath(path string) Key
type HostEndpoint ¶
type HostEndpoint struct { Name string `json:"name,omitempty" validate:"omitempty,interface"` ExpectedIPv4Addrs []net.IP `json:"expected_ipv4_addrs,omitempty" validate:"omitempty,dive,ipv4"` ExpectedIPv6Addrs []net.IP `json:"expected_ipv6_addrs,omitempty" validate:"omitempty,dive,ipv6"` Labels map[string]string `json:"labels,omitempty" validate:"omitempty,labels"` ProfileIDs []string `json:"profile_ids,omitempty" validate:"omitempty,dive,name"` }
type HostEndpointKey ¶
type HostEndpointKey struct { Hostname string `json:"-" validate:"required,hostname"` EndpointID string `json:"-" validate:"required,namespacedName"` }
func (HostEndpointKey) String ¶
func (key HostEndpointKey) String() string
type HostEndpointListOptions ¶
func (HostEndpointListOptions) KeyFromDefaultPath ¶
func (options HostEndpointListOptions) KeyFromDefaultPath(path string) Key
type HostEndpointStatusKey ¶
type HostEndpointStatusKey struct { Hostname string `json:"-" validate:"required,hostname"` EndpointID string `json:"-" validate:"required,namespacedName"` }
func (HostEndpointStatusKey) String ¶
func (key HostEndpointStatusKey) String() string
type HostEndpointStatusListOptions ¶
func (HostEndpointStatusListOptions) KeyFromDefaultPath ¶
func (options HostEndpointStatusListOptions) KeyFromDefaultPath(ekey string) Key
type HostMetadata ¶
type HostMetadata struct { }
type HostMetadataKey ¶
type HostMetadataKey struct {
Hostname string
}
func (HostMetadataKey) String ¶
func (key HostMetadataKey) String() string
type HostMetadataListOptions ¶
type HostMetadataListOptions struct {
Hostname string
}
func (HostMetadataListOptions) KeyFromDefaultPath ¶
func (options HostMetadataListOptions) KeyFromDefaultPath(path string) Key
type IPAMConfig ¶
type IPAMConfigKey ¶
type IPAMConfigKey struct { }
func (IPAMConfigKey) String ¶ added in v1.0.1
func (key IPAMConfigKey) String() string
type IPAMHandle ¶
type IPAMHandleKey ¶
type IPAMHandleKey struct {
HandleID string `json:"id"`
}
func (IPAMHandleKey) String ¶ added in v1.0.1
func (key IPAMHandleKey) String() string
type IPAMHandleListOptions ¶
type IPAMHandleListOptions struct { }
func (IPAMHandleListOptions) KeyFromDefaultPath ¶
func (options IPAMHandleListOptions) KeyFromDefaultPath(path string) Key
type IPAMHost ¶
type IPAMHost struct { }
type IPAMHostKey ¶
type IPAMHostKey struct {
Host string
}
func (IPAMHostKey) String ¶ added in v1.0.1
func (key IPAMHostKey) String() string
type IPNAT ¶
type IPNAT struct { // The internal IP address which must be associated with the owning endpoint via the // configured IPNetworks for the endpoint. IntIP net.IP `json:"int_ip" validate:"ip"` // The external IP address. ExtIP net.IP `json:"ext_ip" validate:"ip"` }
IPNat contains a single NAT mapping for a WorkloadEndpoint resource.
type IPPool ¶
type IPPoolKey ¶
type IPPoolListOptions ¶
func (IPPoolListOptions) KeyFromDefaultPath ¶
func (options IPPoolListOptions) KeyFromDefaultPath(path string) Key
type KVPair ¶
type KVPair struct { Key Key Value interface{} Revision interface{} TTL time.Duration // For writes, if non-zero, key has a TTL. }
KVPair holds a typed key and value object as well as datastore specific revision information.
The Value is dependent on the Key, but in general will be on of the following types:
- A pointer to a struct
- A slice or map
- A bare string, boolean value or IP address (i.e. without quotes, so not JSON format).
type Key ¶
type Key interface { // String returns a unique string representation of this key. The string // returned by this method must uniquely identify this Key. String() string // contains filtered or unexported methods }
Key represents a parsed datastore key.
type LastStatusReportKey ¶
type LastStatusReportKey struct {
Hostname string `json:"-" validate:"required,hostname"`
}
func (LastStatusReportKey) String ¶
func (key LastStatusReportKey) String() string
type LastStatusReportListOptions ¶
type LastStatusReportListOptions struct {
Hostname string
}
func (LastStatusReportListOptions) KeyFromDefaultPath ¶
func (options LastStatusReportListOptions) KeyFromDefaultPath(ekey string) Key
type ListInterface ¶
type ListInterface interface { // BUG(smc) I think we should remove this and use the package KeyFromDefaultPath function. // KeyFromDefaultPath parses the default path representation of the // Key type for this list. It returns nil if passed a different kind // of path. KeyFromDefaultPath(key string) Key // contains filtered or unexported methods }
Interface used to perform datastore lookups.
type Node ¶
type Node struct { // Felix specific configuration FelixIPv4 *net.IP // Node specific labels Labels map[string]string `json:"labels,omitempty"` // BGP specific configuration BGPIPv4Addr *net.IP BGPIPv6Addr *net.IP BGPIPv4Net *net.IPNet BGPIPv6Net *net.IPNet BGPASNumber *numorstring.ASNumber OrchRefs []OrchRef `json:"orchRefs,omitempty"` }
type NodeBGPConfigKey ¶ added in v1.5.0
type NodeBGPConfigKey struct { // The hostname for the host specific BGP config Nodename string `json:"-" validate:"required,name"` // The name of the host specific BGP config key. Name string `json:"-" validate:"required,name"` }
func (NodeBGPConfigKey) String ¶ added in v1.5.0
func (key NodeBGPConfigKey) String() string
type NodeBGPConfigListOptions ¶ added in v1.5.0
func (NodeBGPConfigListOptions) KeyFromDefaultPath ¶ added in v1.5.0
func (options NodeBGPConfigListOptions) KeyFromDefaultPath(path string) Key
type NodeBGPPeerKey ¶ added in v1.5.0
type NodeBGPPeerKey struct { Nodename string `json:"-" validate:"omitempty"` PeerIP net.IP `json:"-" validate:"required"` }
func (NodeBGPPeerKey) String ¶ added in v1.5.0
func (key NodeBGPPeerKey) String() string
type NodeBGPPeerListOptions ¶ added in v1.5.0
func (NodeBGPPeerListOptions) KeyFromDefaultPath ¶ added in v1.5.0
func (options NodeBGPPeerListOptions) KeyFromDefaultPath(path string) Key
type NodeListOptions ¶
type NodeListOptions struct {
Hostname string
}
func (NodeListOptions) KeyFromDefaultPath ¶
func (options NodeListOptions) KeyFromDefaultPath(path string) Key
type OrchRef ¶ added in v1.7.2
type OrchRefKey ¶ added in v1.7.2
type OrchRefKey struct {
Hostname string
}
func (OrchRefKey) String ¶ added in v1.7.2
func (key OrchRefKey) String() string
type OrchRefListOptions ¶ added in v1.7.2
type OrchRefListOptions struct {
Hostname string
}
func (OrchRefListOptions) KeyFromDefaultPath ¶ added in v1.7.2
func (options OrchRefListOptions) KeyFromDefaultPath(path string) Key
type Policy ¶
type Policy struct { Order *float64 `json:"order,omitempty" validate:"omitempty"` InboundRules []Rule `json:"inbound_rules,omitempty" validate:"omitempty,dive"` OutboundRules []Rule `json:"outbound_rules,omitempty" validate:"omitempty,dive"` Selector string `json:"selector" validate:"selector"` DoNotTrack bool `json:"untracked,omitempty"` Annotations map[string]string `json:"annotations,omitempty"` PreDNAT bool `json:"pre_dnat,omitempty"` Types []string `json:"types,omitempty"` }
type PolicyListOptions ¶
type PolicyListOptions struct {
Name string
}
func (PolicyListOptions) KeyFromDefaultPath ¶
func (options PolicyListOptions) KeyFromDefaultPath(path string) Key
type Profile ¶
type Profile struct { Rules ProfileRules Tags []string Labels map[string]string }
The profile structure is defined to allow the client to define a conversion interface to map between the API and backend profiles. However, in the actual underlying implementation the profile is written as three separate entries - rules, tags and labels.
type ProfileKey ¶
type ProfileKey struct {
Name string `json:"-" validate:"required,name"`
}
The profile key actually returns the common parent of the three separate entries. It is useful to define this to re-use some of the common machinery, and can be used for delete processing since delete needs to remove the common parent.
func (ProfileKey) String ¶
func (key ProfileKey) String() string
type ProfileLabelsKey ¶
type ProfileLabelsKey struct {
ProfileKey
}
ProfileLabelsKey implements the KeyInterface for the profile labels
func (ProfileLabelsKey) String ¶
func (key ProfileLabelsKey) String() string
type ProfileListOptions ¶
type ProfileListOptions struct {
Name string
}
func (ProfileListOptions) KeyFromDefaultPath ¶
func (options ProfileListOptions) KeyFromDefaultPath(path string) Key
func (*ProfileListOptions) ListConvert ¶
func (_ *ProfileListOptions) ListConvert(ds []*KVPair) []*KVPair
type ProfileRules ¶
type ProfileRulesKey ¶
type ProfileRulesKey struct {
ProfileKey
}
ProfileRulesKey implements the KeyInterface for the profile rules
func (ProfileRulesKey) String ¶
func (key ProfileRulesKey) String() string
type ProfileTagsKey ¶
type ProfileTagsKey struct {
ProfileKey
}
ProfileTagsKey implements the KeyInterface for the profile tags
func (ProfileTagsKey) String ¶
func (key ProfileTagsKey) String() string
type ReadyFlagKey ¶
type ReadyFlagKey struct { }
func (ReadyFlagKey) String ¶ added in v1.0.1
func (key ReadyFlagKey) String() string
type Rule ¶
type Rule struct { Action string `json:"action,omitempty" validate:"backendaction"` IPVersion *int `json:"ip_version,omitempty" validate:"omitempty,ipversion"` Protocol *numorstring.Protocol `json:"protocol,omitempty" validate:"omitempty"` NotProtocol *numorstring.Protocol `json:"!protocol,omitempty" validate:"omitempty"` // ICMP validation notes: 0 is a valid (common) ICMP type and code. Type = 255 is not assigned // to any protocol and the Linux kernel doesn't support matching on it so we validate against // it. ICMPType *int `json:"icmp_type,omitempty" validate:"omitempty,gte=0,lt=255"` ICMPCode *int `json:"icmp_code,omitempty" validate:"omitempty,gte=0,lte=255"` NotICMPType *int `json:"!icmp_type,omitempty" validate:"omitempty,gte=0,lt=255"` NotICMPCode *int `json:"!icmp_code,omitempty" validate:"omitempty,gte=0,lte=255"` SrcTag string `json:"src_tag,omitempty" validate:"omitempty,tag"` SrcNet *net.IPNet `json:"src_net,omitempty" validate:"omitempty"` SrcNets []*net.IPNet `json:"src_nets,omitempty" validate:"omitempty"` SrcSelector string `json:"src_selector,omitempty" validate:"omitempty,selector"` SrcPorts []numorstring.Port `json:"src_ports,omitempty" validate:"omitempty"` DstTag string `json:"dst_tag,omitempty" validate:"omitempty,tag"` DstSelector string `json:"dst_selector,omitempty" validate:"omitempty,selector"` DstNet *net.IPNet `json:"dst_net,omitempty" validate:"omitempty"` DstNets []*net.IPNet `json:"dst_nets,omitempty" validate:"omitempty"` DstPorts []numorstring.Port `json:"dst_ports,omitempty" validate:"omitempty"` NotSrcTag string `json:"!src_tag,omitempty" validate:"omitempty,tag"` NotSrcNet *net.IPNet `json:"!src_net,omitempty" validate:"omitempty"` NotSrcNets []*net.IPNet `json:"!src_nets,omitempty" validate:"omitempty"` NotSrcSelector string `json:"!src_selector,omitempty" validate:"omitempty,selector"` NotSrcPorts []numorstring.Port `json:"!src_ports,omitempty" validate:"omitempty"` NotDstTag string `json:"!dst_tag,omitempty" validate:"omitempty"` NotDstSelector string `json:"!dst_selector,omitempty" validate:"omitempty,selector"` NotDstNet *net.IPNet `json:"!dst_net,omitempty" validate:"omitempty"` NotDstNets []*net.IPNet `json:"!dst_nets,omitempty" validate:"omitempty"` NotDstPorts []numorstring.Port `json:"!dst_ports,omitempty" validate:"omitempty"` LogPrefix string `json:"log_prefix,omitempty" validate:"omitempty"` }
type StatusReport ¶
type WorkloadEndpoint ¶
type WorkloadEndpoint struct { // TODO: Validation for workload endpoint. State string `json:"state"` Name string `json:"name"` ActiveInstanceID string `json:"active_instance_id"` Mac *net.MAC `json:"mac"` ProfileIDs []string `json:"profile_ids"` IPv4Nets []net.IPNet `json:"ipv4_nets"` IPv6Nets []net.IPNet `json:"ipv6_nets"` IPv4NAT []IPNAT `json:"ipv4_nat,omitempty"` IPv6NAT []IPNAT `json:"ipv6_nat,omitempty"` Labels map[string]string `json:"labels,omitempty"` IPv4Gateway *net.IP `json:"ipv4_gateway,omitempty" validate:"omitempty,ipv4"` IPv6Gateway *net.IP `json:"ipv6_gateway,omitempty" validate:"omitempty,ipv6"` }
type WorkloadEndpointKey ¶
type WorkloadEndpointKey struct { Hostname string `json:"-"` OrchestratorID string `json:"-"` WorkloadID string `json:"-"` EndpointID string `json:"-"` }
func (WorkloadEndpointKey) String ¶
func (key WorkloadEndpointKey) String() string
type WorkloadEndpointListOptions ¶
type WorkloadEndpointListOptions struct { Hostname string OrchestratorID string WorkloadID string EndpointID string }
func (WorkloadEndpointListOptions) KeyFromDefaultPath ¶
func (options WorkloadEndpointListOptions) KeyFromDefaultPath(path string) Key
type WorkloadEndpointStatusKey ¶
type WorkloadEndpointStatusKey struct { Hostname string `json:"-"` OrchestratorID string `json:"-"` WorkloadID string `json:"-"` EndpointID string `json:"-"` }
func (WorkloadEndpointStatusKey) String ¶
func (key WorkloadEndpointStatusKey) String() string
type WorkloadEndpointStatusListOptions ¶
type WorkloadEndpointStatusListOptions struct { Hostname string OrchestratorID string WorkloadID string EndpointID string }
func (WorkloadEndpointStatusListOptions) KeyFromDefaultPath ¶
func (options WorkloadEndpointStatusListOptions) KeyFromDefaultPath(ekey string) Key
Notes ¶
Bugs ¶
I think we should remove this and use the package KeyFromDefaultPath function. KeyFromDefaultPath parses the default path representation of the Key type for this list. It returns nil if passed a different kind of path.