Add Mysql variables to collector (#562)

* Add Mysql variables to collector

* Cleanup row scanning and a few updates based on feedback

* Close db connection

* Move defer db.close

* Updates based on feedback

* Use vars in loop instead of struct

* Only pull parameters specified in collector config

Co-authored-by: Ethan Mosbaugh <[email protected]>

Author: Edgar Ochoa

pkg/apis/troubleshoot/v1beta2/collector_shared.go

@@ -156,7 +156,8 @@ type Put struct {
 
 type Database struct {
 	CollectorMeta `json:",inline" yaml:",inline"`
-	URI           string `json:"uri" yaml:"uri"`
+	URI           string   `json:"uri" yaml:"uri"`
+	Parameters    []string `json:"parameters,omitempty"`
 }
 
 type Collectd struct {

pkg/collect/database_shared.go

@@ -1,7 +1,8 @@
 package collect
 
 type DatabaseConnection struct {
-	IsConnected bool   `json:"isConnected"`
-	Error       string `json:"error,omitempty"`
-	Version     string `json:"version,omitempty"`
+	IsConnected bool              `json:"isConnected"`
+	Error       string            `json:"error,omitempty"`
+	Version     string            `json:"version,omitempty"`
+	Variables   map[string]string `json:"variables,omitempty"`
 }

pkg/collect/mysql.go

@@ -18,15 +18,49 @@ func Mysql(c *Collector, databaseCollector *troubleshootv1beta2.Database) (Colle
 	if err != nil {
 		databaseConnection.Error = err.Error()
 	} else {
+		defer db.Close()
 		query := `select version()`
 		row := db.QueryRow(query)
+
 		version := ""
 		if err := row.Scan(&version); err != nil {
 			databaseConnection.Error = err.Error()
 		} else {
 			databaseConnection.IsConnected = true
 			databaseConnection.Version = version
 		}
+
+		requestedParameters := databaseCollector.Parameters
+		if len(requestedParameters) > 0 {
+			rows, err := db.Query("SHOW VARIABLES")
+
+			if err != nil {
+				databaseConnection.Error = err.Error()
+			} else {
+				defer rows.Close()
+
+				variables := map[string]string{}
+				for rows.Next() {
+					var key, value string
+					err = rows.Scan(&key, &value)
+					if err != nil {
+						databaseConnection.Error = err.Error()
+						break
+					}
+					variables[key] = value
+				}
+				filteredVariables := map[string]string{}
+
+				for _, key := range requestedParameters {
+					if value, ok := variables[key]; ok {
+						filteredVariables[key] = value
+					}
+
+				}
+				databaseConnection.Variables = filteredVariables
+			}
+		}
+
 	}
 
 	b, err := json.Marshal(databaseConnection)