package structs import ( "bytes" "fmt" "github.com/ugorji/go/codec" "time" ) var ( ErrNoLeader = fmt.Errorf("No cluster leader") ErrNoDCPath = fmt.Errorf("No path to datacenter") ErrNoServers = fmt.Errorf("No known Consul servers") ) type MessageType uint8 const ( RegisterRequestType MessageType = iota DeregisterRequestType KVSRequestType SessionRequestType ) const ( // HealthAny is special, and is used as a wild card, // not as a specific state. HealthAny = "any" HealthUnknown = "unknown" HealthPassing = "passing" HealthWarning = "warning" HealthCritical = "critical" ) const ( // MaxLockDelay provides a maximum LockDelay value for // a session. Any value above this will not be respected. MaxLockDelay = 60 * time.Second ) // RPCInfo is used to describe common information about query type RPCInfo interface { RequestDatacenter() string IsRead() bool AllowStaleRead() bool } // QueryOptions is used to specify various flags for read queries type QueryOptions struct { // If set, wait until query exceeds given index. Must be provided // with MaxQueryTime. MinQueryIndex uint64 // Provided with MinQueryIndex to wait for change. MaxQueryTime time.Duration // If set, any follower can service the request. Results // may be arbitrarily stale. AllowStale bool // If set, the leader must verify leadership prior to // servicing the request. Prevents a stale read. RequireConsistent bool } // QueryOption only applies to reads, so always true func (q QueryOptions) IsRead() bool { return true } func (q QueryOptions) AllowStaleRead() bool { return q.AllowStale } type WriteRequest struct{} // WriteRequest only applies to writes, always false func (w WriteRequest) IsRead() bool { return false } func (w WriteRequest) AllowStaleRead() bool { return false } // QueryMeta allows a query response to include potentially // useful metadata about a query type QueryMeta struct { // This is the index associated with the read Index uint64 // If AllowStale is used, this is time elapsed since // last contact between the follower and leader. This // can be used to gauge staleness. LastContact time.Duration // Used to indicate if there is a known leader node KnownLeader bool } // RegisterRequest is used for the Catalog.Register endpoint // to register a node as providing a service. If no service // is provided, the node is registered. type RegisterRequest struct { Datacenter string Node string Address string Service *NodeService Check *HealthCheck WriteRequest } func (r *RegisterRequest) RequestDatacenter() string { return r.Datacenter } // DeregisterRequest is used for the Catalog.Deregister endpoint // to deregister a node as providing a service. If no service is // provided the entire node is deregistered. type DeregisterRequest struct { Datacenter string Node string ServiceID string CheckID string WriteRequest } func (r *DeregisterRequest) RequestDatacenter() string { return r.Datacenter } // DCSpecificRequest is used to query about a specific DC type DCSpecificRequest struct { Datacenter string QueryOptions } func (r *DCSpecificRequest) RequestDatacenter() string { return r.Datacenter } // ServiceSpecificRequest is used to query about a specific node type ServiceSpecificRequest struct { Datacenter string ServiceName string ServiceTag string TagFilter bool // Controls tag filtering QueryOptions } func (r *ServiceSpecificRequest) RequestDatacenter() string { return r.Datacenter } // NodeSpecificRequest is used to request the information about a single node type NodeSpecificRequest struct { Datacenter string Node string QueryOptions } func (r *NodeSpecificRequest) RequestDatacenter() string { return r.Datacenter } // ChecksInStateRequest is used to query for nodes in a state type ChecksInStateRequest struct { Datacenter string State string QueryOptions } func (r *ChecksInStateRequest) RequestDatacenter() string { return r.Datacenter } // Used to return information about a node type Node struct { Node string Address string } type Nodes []Node // Used to return information about a provided services. // Maps service name to available tags type Services map[string][]string // ServiceNode represents a node that is part of a service type ServiceNode struct { Node string Address string ServiceID string ServiceName string ServiceTags []string ServicePort int } type ServiceNodes []ServiceNode // NodeService is a service provided by a node type NodeService struct { ID string Service string Tags []string Port int } type NodeServices struct { Node Node Services map[string]*NodeService } // HealthCheck represents a single check on a given node type HealthCheck struct { Node string CheckID string // Unique per-node ID Name string // Check name Status string // The current check status Notes string // Additional notes with the status Output string // Holds output of script runs ServiceID string // optional associated service ServiceName string // optional service name } type HealthChecks []*HealthCheck // CheckServiceNode is used to provide the node, it's service // definition, as well as a HealthCheck that is associated type CheckServiceNode struct { Node Node Service NodeService Checks HealthChecks } type CheckServiceNodes []CheckServiceNode // NodeInfo is used to dump all associated information about // a node. This is currently used for the UI only, as it is // rather expensive to generate. type NodeInfo struct { Node string Address string Services []*NodeService Checks []*HealthCheck } // NodeDump is used to dump all the nodes with all their // associated data. This is currently used for the UI only, // as it is rather expensive to generate. type NodeDump []*NodeInfo type IndexedNodes struct { Nodes Nodes QueryMeta } type IndexedServices struct { Services Services QueryMeta } type IndexedServiceNodes struct { ServiceNodes ServiceNodes QueryMeta } type IndexedNodeServices struct { NodeServices *NodeServices QueryMeta } type IndexedHealthChecks struct { HealthChecks HealthChecks QueryMeta } type IndexedCheckServiceNodes struct { Nodes CheckServiceNodes QueryMeta } type IndexedNodeDump struct { Dump NodeDump QueryMeta } // DirEntry is used to represent a directory entry. This is // used for values in our Key-Value store. type DirEntry struct { CreateIndex uint64 ModifyIndex uint64 LockIndex uint64 Key string Flags uint64 Value []byte Session string `json:",omitempty"` } type DirEntries []*DirEntry type KVSOp string const ( KVSSet KVSOp = "set" KVSDelete = "delete" KVSDeleteTree = "delete-tree" KVSCAS = "cas" // Check-and-set KVSLock = "lock" // Lock a key KVSUnlock = "unlock" // Unlock a key ) // KVSRequest is used to operate on the Key-Value store type KVSRequest struct { Datacenter string Op KVSOp // Which operation are we performing DirEnt DirEntry // Which directory entry WriteRequest } func (r *KVSRequest) RequestDatacenter() string { return r.Datacenter } // KeyRequest is used to request a key, or key prefix type KeyRequest struct { Datacenter string Key string QueryOptions } func (r *KeyRequest) RequestDatacenter() string { return r.Datacenter } // KeyListRequest is used to list keys type KeyListRequest struct { Datacenter string Prefix string Seperator string QueryOptions } func (r *KeyListRequest) RequestDatacenter() string { return r.Datacenter } type IndexedDirEntries struct { Entries DirEntries QueryMeta } type IndexedKeyList struct { Keys []string QueryMeta } // Session is used to represent an open session in the KV store. // This issued to associate node checks with acquired locks. type Session struct { CreateIndex uint64 ID string Name string Node string Checks []string LockDelay time.Duration } type Sessions []*Session type SessionOp string const ( SessionCreate SessionOp = "create" SessionDestroy = "destroy" ) // SessionRequest is used to operate on sessions type SessionRequest struct { Datacenter string Op SessionOp // Which operation are we performing Session Session // Which session WriteRequest } func (r *SessionRequest) RequestDatacenter() string { return r.Datacenter } // SessionSpecificRequest is used to request a session by ID type SessionSpecificRequest struct { Datacenter string Session string QueryOptions } func (r *SessionSpecificRequest) RequestDatacenter() string { return r.Datacenter } type IndexedSessions struct { Sessions Sessions QueryMeta } // msgpackHandle is a shared handle for encoding/decoding of structs var msgpackHandle = &codec.MsgpackHandle{} // Decode is used to decode a MsgPack encoded object func Decode(buf []byte, out interface{}) error { return codec.NewDecoder(bytes.NewReader(buf), msgpackHandle).Decode(out) } // Encode is used to encode a MsgPack object with type prefix func Encode(t MessageType, msg interface{}) ([]byte, error) { var buf bytes.Buffer buf.WriteByte(uint8(t)) err := codec.NewEncoder(&buf, msgpackHandle).Encode(msg) return buf.Bytes(), err }