metricsql

type AggrFuncExpr struct {
	// Name is the function name.
	Name string

	// Args is the function args.
	Args []Expr

	// Modifier is optional modifier such as `by (...)` or `without (...)`.
	Modifier ModifierExpr

	// Optional limit for the number of output time series.
	// This is MetricsQL extension.
	//
	// Example: `sum(...) by (...) limit 10` would return maximum 10 time series.
	Limit int
}

type BinaryOpExpr struct {
	// Op is the operation itself, i.e. `+`, `-`, `*`, etc.
	Op string

	// Bool indicates whether `bool` modifier is present.
	// For example, `foo >bool bar`.
	Bool bool

	// GroupModifier contains modifier such as "on" or "ignoring".
	GroupModifier ModifierExpr

	// JoinModifier contains modifier such as "group_left" or "group_right".
	JoinModifier ModifierExpr

	// JoinModifierPrefix is an optional prefix to add to labels specified inside group_left() or group_right() lists.
	//
	// The syntax is `group_left(foo,bar) prefix "abc"`
	JoinModifierPrefix *StringExpr

	// If KeepMetricNames is set to true, then the operation should keep metric names.
	KeepMetricNames bool

	// Left contains left arg for the `left op right` expression.
	Left Expr

	// Right contains right arg for the `left op right` epxression.
	Right Expr
}

type DurationExpr struct {
	// contains filtered or unexported fields
}

type Expr interface {
	// AppendString appends string representation of Expr to dst.
	AppendString(dst []byte) []byte
}

type FuncExpr struct {
	// Name is function name.
	Name string

	// Args contains function args.
	Args []Expr

	// If KeepMetricNames is set to true, then the function should keep metric names.
	KeepMetricNames bool
}

type LabelFilter struct {
	// Label contains label name for the filter.
	Label string

	// Value contains unquoted value for the filter.
	Value string

	// IsNegative reperesents whether the filter is negative, i.e. '!=' or '!~'.
	IsNegative bool

	// IsRegexp represents whether the filter is regesp, i.e. `=~` or `!~`.
	IsRegexp bool
}

type MetricExpr struct {
	// LabelFilters contains a list of or-delimited groups of label filters from curly braces.
	// Filter for metric name (aka __name__ label) must go first in every group.
	LabelFilterss [][]LabelFilter
	// contains filtered or unexported fields
}

type ModifierExpr struct {
	// Op is modifier operation.
	Op string

	// Args contains modifier args from parens.
	Args []string
}

type NumberExpr struct {
	// N is the parsed number, i.e. `1.23`, `-234`, etc.
	N float64
	// contains filtered or unexported fields
}

type RollupExpr struct {
	// The expression for the rollup. Usually it is MetricExpr, but may be arbitrary expr
	// if subquery is used. https://prometheus.io/blog/2019/01/28/subquery-support/
	Expr Expr

	// Window contains optional window value from square brackets
	//
	// For example, `http_requests_total[5m]` will have Window value `5m`.
	Window *DurationExpr

	// Offset contains optional value from `offset` part.
	//
	// For example, `foobar{baz="aa"} offset 5m` will have Offset value `5m`.
	Offset *DurationExpr

	// Step contains optional step value from square brackets.
	//
	// For example, `foobar[1h:3m]` will have Step value '3m'.
	Step *DurationExpr

	// If set to true, then `foo[1h:]` would print the same
	// instead of `foo[1h]`.
	InheritStep bool

	// At contains an optional expression after `@` modifier.
	//
	// For example, `foo @ end()` or `bar[5m] @ 12345`
	// See https://prometheus.io/docs/prometheus/latest/querying/basics/#modifier
	At Expr
}

type StringExpr struct {
	// S contains unquoted value for string expression.
	S string
	// contains filtered or unexported fields
}