API: Extract OpenAPI specification from source code using go-swagger (#40528)

* API: Using go-swagger for extracting OpenAPI specification from source code

* Merge Grafana Alerting spec

* Include enterprise endpoints (if enabled)

* Serve SwaggerUI under feature flag

* Fix building dev docker images

* Configure swaggerUI

* Add missing json tags

Co-authored-by: Ying WANG <ying.wang@grafana.com>
Co-authored-by: Marcus Efraimsson <marcus.efraimsson@gmail.com>

pkg/api/dtos/models.go

@@ -48,11 +48,25 @@ type CurrentUser struct {
 
 type UserPermissionsMap map[string]bool
 
+// swagger:model
 type MetricRequest struct {
-	From    string             `json:"from"`
-	To      string             `json:"to"`
+	// From Start time in epoch timestamps in milliseconds or relative using Grafana time units.
+	// required: true
+	// example: now-1h
+	From string `json:"from"`
+	// To End time in epoch timestamps in milliseconds or relative using Grafana time units.
+	// required: true
+	// example: now
+	To string `json:"to"`
+	// queries.refId – Specifies an identifier of the query. Is optional and default to “A”.
+	// queries.datasourceId – Specifies the data source to be queried. Each query in the request must have an unique datasourceId.
+	// queries.maxDataPoints - Species maximum amount of data points that dashboard panel can render. Is optional and default to 100.
+	// queries.intervalMs - Specifies the time interval in milliseconds of time series. Is optional and defaults to 1000.
+	// required: true
+	// example: [ { "refId": "A", "intervalMs": 86400000, "maxDataPoints": 1092, "datasourceId": 86, "rawSql": "SELECT 1 as valueOne, 2 as valueTwo", "format": "table" } ]
 	Queries []*simplejson.Json `json:"queries"`
-	Debug   bool               `json:"debug"`
+	// required: false
+	Debug bool `json:"debug"`
 }
 
 func GetGravatarUrl(text string) string {