feature: Adds 404 retry & close on dispose

Author: NeedleInAJayStack

DEVELOPMENT_GUIDE.md

@@ -53,12 +53,6 @@ achieved with the following steps:
 1. Run `npm version <major|minor|patch>`
 2. Run `git push origin main --follow-tags`
 
-
-# TODO
-
-* [ ] Add support for non-eval queries (read, hisRead, etc)
-* [ ] Improve login/logout and add auth/retry logic
-
 ---
 
 Below is the original readme generated by Grafana

README.md

@@ -51,3 +51,6 @@ To use them, simply use the value in the input string like this:
 [{ts: $__timeRange_start, v0: 0}, {ts: $__timeRange_end, v0: 10}].toGrid
 ```
 
+# Continuing Work
+
+* [ ] Publish plugin

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 v0.1.5
+	github.com/NeedleInAJayStack/haystack v0.1.6
 	github.com/joho/godotenv v1.5.1
 )
 

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 v0.1.5 h1:pT+xWnXH6ogtqXbBXyg0TSFJAwCscjrTTAESyR3eAyE=
-github.com/NeedleInAJayStack/haystack v0.1.5/go.mod h1:Oho5sG64nQS27mApp6gWOUi7m4OgzpWllZrOtZn8qss=
+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/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

@@ -68,7 +68,7 @@ type Options struct {
 // created. As soon as datasource settings change detected by SDK old datasource instance will
 // be disposed and a new one will be created using NewSampleDatasource factory function.
 func (datasource *Datasource) Dispose() {
-	// Clean up datasource instance resources.
+	datasource.client.Close()
 }
 
 // QueryData handles multiple queries and returns multiple responses.
@@ -189,7 +189,19 @@ func (datasource *Datasource) eval(expr string, variables map[string]string) (ha
 	for name, val := range variables {
 		expr = strings.ReplaceAll(expr, name, val)
 	}
-	return datasource.client.Eval(expr)
+	result, err := datasource.client.Eval(expr)
+	// 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.Eval(expr)
+		} else {
+			return result, err
+		}
+	default:
+		return result, err
+	}
 }
 
 func (datasource *Datasource) hisRead(id string, timeRange backend.TimeRange) (haystack.Grid, error) {