feature: Adds op querying to backend

Author: NeedleInAJayStack

go.mod

@@ -5,7 +5,7 @@ go 1.19
 require github.com/grafana/grafana-plugin-sdk-go v0.149.1
 
 require (
-	github.com/NeedleInAJayStack/haystack v0.1.6
+	github.com/NeedleInAJayStack/haystack v0.1.7
 	github.com/google/go-cmp v0.5.9
 )
 

go.sum

@@ -35,8 +35,8 @@ gioui.org v0.0.0-20210308172011-57750fc8a0a6/go.mod h1:RSH6KIUZ0p2xy5zHDxgAM4zum
 github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
-github.com/NeedleInAJayStack/haystack v0.1.6 h1:LhV4SO2Jgjq8YQPd/JcJdb/a3cq9+Lu548vTDj0NakU=
-github.com/NeedleInAJayStack/haystack v0.1.6/go.mod h1:Oho5sG64nQS27mApp6gWOUi7m4OgzpWllZrOtZn8qss=
+github.com/NeedleInAJayStack/haystack v0.1.7 h1:G0w/DdH6OiPv0pALTvaMYvBIorLaz3yhMupHTqn17Zc=
+github.com/NeedleInAJayStack/haystack v0.1.7/go.mod h1:Oho5sG64nQS27mApp6gWOUi7m4OgzpWllZrOtZn8qss=
 github.com/ajstarks/svgo v0.0.0-20180226025133-644b8db467af/go.mod h1:K08gAheRH3/J6wwsYMMT4xOr94bZjxIelGM0+d/wbFw=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=

pkg/plugin/datasource.go

@@ -123,6 +123,13 @@ func (datasource *Datasource) query(ctx context.Context, pCtx backend.PluginCont
 
 	var grid haystack.Grid
 	switch model.Type {
+	case "Ops":
+		ops, err := datasource.ops()
+		if err != nil {
+			log.DefaultLogger.Error(err.Error())
+			return backend.ErrDataResponse(backend.StatusBadRequest, fmt.Sprintf("Ops eval failure: %v", err.Error()))
+		}
+		grid = ops
 	case "Eval":
 		eval, err := datasource.eval(model.Eval, variables)
 		if err != nil {
@@ -185,6 +192,22 @@ func (datasource *Datasource) CheckHealth(_ context.Context, req *backend.CheckH
 	}, nil
 }
 
+func (datasource *Datasource) ops() (haystack.Grid, error) {
+	result, err := datasource.client.Ops()
+	// If the error is a 404, try to reconnect and try again
+	switch error := err.(type) {
+	case client.HTTPError:
+		if error.Code == 404 {
+			datasource.client.Open()
+			return datasource.client.Ops()
+		} else {
+			return result, err
+		}
+	default:
+		return result, err
+	}
+}
+
 func (datasource *Datasource) eval(expr string, variables map[string]string) (haystack.Grid, error) {
 	for name, val := range variables {
 		expr = strings.ReplaceAll(expr, name, val)

pkg/plugin/datasource_test.go

@@ -185,6 +185,11 @@ func (c *testHaystackClient) About() (haystack.Dict, error) {
 	return haystack.Dict{}, nil
 }
 
+// Ops returns an empty grid
+func (c *testHaystackClient) Ops() (haystack.Grid, error) {
+	return haystack.EmptyGrid(), nil
+}
+
 // Eval returns the EvalResponse
 func (c *testHaystackClient) Eval(query string) (haystack.Grid, error) {
 	return c.evalResponse, nil

pkg/plugin/haystackClient.go

@@ -9,6 +9,7 @@ type HaystackClient interface {
 	Open() error
 	Close() error
 	About() (haystack.Dict, error)
+	Ops() (haystack.Grid, error)
 	Eval(string) (haystack.Grid, error)
 	HisReadAbsDateTime(haystack.Ref, haystack.DateTime, haystack.DateTime) (haystack.Grid, error)
 	Read(string) (haystack.Grid, error)