SQL Expressions: Add endpoint to get Schemas (#108864)

Return the SQL schema for all DS queries in request (to provide information to AI / Autocomplete for SQL expressions).

All DS queries are treated as if they were inputs to SQL expressions in terms of conversion, regardless if they are selected in a query or not.

Requires feature toggle queryService = true

Endpoint is apis/query.grafana.app/v0alpha1/namespaces/default/sqlschemas

---------

Co-authored-by: Todd Treece <360020+toddtreece@users.noreply.github.com>

pkg/apis/query/v0alpha1/query.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/grafana/grafana-plugin-sdk-go/backend"
 	data "github.com/grafana/grafana-plugin-sdk-go/experimental/apis/data/v0alpha1"
+	"github.com/grafana/grafana/pkg/expr"
 )
 
 // Generic query request with shared time across all values
@@ -28,6 +29,14 @@ type QueryDataResponse struct {
 	backend.QueryDataResponse `json:",inline"`
 }
 
+// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
+type SQLSchemas struct {
+	metav1.TypeMeta `json:",inline"`
+
+	// Backend wrapper (external dependency)
+	expr.SQLSchemas `json:"sqlSchemas,inline"`
+}
+
 // GetResponseCode return the right status code for the response by checking the responses.
 func GetResponseCode(rsp *backend.QueryDataResponse) int {
 	if rsp == nil {

pkg/apis/query/v0alpha1/zz_generated.deepcopy.go

@@ -262,3 +262,29 @@ func (in *QueryTypeDefinitionList) DeepCopyObject() runtime.Object {
 	}
 	return nil
 }
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *SQLSchemas) DeepCopyInto(out *SQLSchemas) {
+	*out = *in
+	out.TypeMeta = in.TypeMeta
+	out.SQLSchemas = in.SQLSchemas.DeepCopy()
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new SQLSchemas.
+func (in *SQLSchemas) DeepCopy() *SQLSchemas {
+	if in == nil {
+		return nil
+	}
+	out := new(SQLSchemas)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyObject is an autogenerated deepcopy function, copying the receiver, creating a new runtime.Object.
+func (in *SQLSchemas) DeepCopyObject() runtime.Object {
+	if c := in.DeepCopy(); c != nil {
+		return c
+	}
+	return nil
+}

pkg/apis/query/v0alpha1/zz_generated.openapi.go

@@ -23,6 +23,7 @@ func GetOpenAPIDefinitions(ref common.ReferenceCallback) map[string]common.OpenA
 		"github.com/grafana/grafana/pkg/apis/query/v0alpha1.QueryDataResponse":        schema_pkg_apis_query_v0alpha1_QueryDataResponse(ref),
 		"github.com/grafana/grafana/pkg/apis/query/v0alpha1.QueryTypeDefinition":      schema_pkg_apis_query_v0alpha1_QueryTypeDefinition(ref),
 		"github.com/grafana/grafana/pkg/apis/query/v0alpha1.QueryTypeDefinitionList":  schema_pkg_apis_query_v0alpha1_QueryTypeDefinitionList(ref),
+		"github.com/grafana/grafana/pkg/apis/query/v0alpha1.SQLSchemas":               schema_pkg_apis_query_v0alpha1_SQLSchemas(ref),
 	}
 }
 
@@ -482,3 +483,29 @@ func schema_pkg_apis_query_v0alpha1_QueryTypeDefinitionList(ref common.Reference
 			"github.com/grafana/grafana/pkg/apis/query/v0alpha1.QueryTypeDefinition", "k8s.io/apimachinery/pkg/apis/meta/v1.ListMeta"},
 	}
 }
+
+func schema_pkg_apis_query_v0alpha1_SQLSchemas(ref common.ReferenceCallback) common.OpenAPIDefinition {
+	return common.OpenAPIDefinition{
+		Schema: spec.Schema{
+			SchemaProps: spec.SchemaProps{
+				Type: []string{"object"},
+				Properties: map[string]spec.Schema{
+					"kind": {
+						SchemaProps: spec.SchemaProps{
+							Description: "Kind is a string value representing the REST resource this object represents. Servers may infer this from the endpoint the client submits requests to. Cannot be updated. In CamelCase. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds",
+							Type:        []string{"string"},
+							Format:      "",
+						},
+					},
+					"apiVersion": {
+						SchemaProps: spec.SchemaProps{
+							Description: "APIVersion defines the versioned schema of this representation of an object. Servers should convert recognized schemas to the latest internal value, and may reject unrecognized values. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources",
+							Type:        []string{"string"},
+							Format:      "",
+						},
+					},
+				},
+			},
+		},
+	}
+}