first draft of the storage engine interface.

src/interfaces/se.go

@@ -0,0 +1,90 @@
+package interfaces
+
+import (
+	"time"
+)
+
+type FieldType int
+
+const (
+	StringType FieldType = iota
+	IntType
+	FloatType
+)
+
+type Field struct {
+	Name  string
+	Value interface{}
+	Type  FieldType
+}
+
+type Point struct {
+	Fields []*Field
+}
+
+type Timeseries struct {
+	Name   string
+	Points []*Point
+}
+
+type WriteRequest struct {
+	Timeseries []*Timeseries
+}
+
+type Operation int
+
+const (
+	EqualOperation Operation = iota
+	NotEqualOperation
+	GreaterThanOperation
+	GreaterThanOrEqualOperation
+	LessThanOperation
+	LessThanOrEqualOperation
+)
+
+type Condition interface {
+	IsCondition()
+}
+
+type CombineOperation int
+
+// definition of combining operators with order of precedence
+const (
+	NotOperation CombineOperation = iota // First has to be nil
+	AndOperation
+	OrOperation
+)
+
+type CombiningCondition struct {
+	First     *Condition
+	CombineOp CombineOperation
+	Second    *Condition
+}
+
+type ComparisonCondition struct {
+	FieldName string
+	Op        Operation
+	Value     interface{}
+}
+
+// TODO: applying functions and joining time series
+type ReadRequest struct {
+	Timeseries   string
+	IsRegex      bool // is the timeseries name a regex?
+	StartTime    time.Time
+	EndTime      time.Time
+	IsContinuous bool
+	Conditions   []*Condition
+}
+
+type StorageEngineProcessingI interface {
+	WritePoints(request *WriteRequest) error
+	ReadPoints(request *ReadRequest, yield func(pts []*Point) error) error
+}
+
+type StorageEngineConsensusI interface {
+	// TODO: figure out the requirements of this interface. Probably the following
+	// 1. Transfer part(s) of the ring to other node(s)
+	// 2. Give up ownership of part(s) of the ring
+	// 3. Take ownership of part(s) of the ring
+}