Implement node query

api/schema.graphqls

@@ -393,7 +393,6 @@ type TimeRangeOutput {
 input NodeFilter {
   hostname: StringInput
   cluster: StringInput
-  subCluster: StringInput
   nodeState: NodeState
   healthState: MonitoringState
 }

internal/repository/node.go

@@ -5,6 +5,7 @@
 package repository
 
 import (
+	"context"
 	"database/sql"
 	"encoding/json"
 	"fmt"
@@ -12,6 +13,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/ClusterCockpit/cc-backend/internal/graph/model"
 	"github.com/ClusterCockpit/cc-backend/pkg/archive"
 	"github.com/ClusterCockpit/cc-backend/pkg/log"
 	"github.com/ClusterCockpit/cc-backend/pkg/lrucache"
@@ -212,8 +214,51 @@ func (r *NodeRepository) DeleteNode(id int64) error {
 	return nil
 }
 
-func (r *NodeRepository) QueryNodes() ([]*schema.Node, error) {
-	return nil, nil
+func (r *NodeRepository) QueryNodes(
+	ctx context.Context,
+	filters []*model.NodeFilter,
+) ([]*schema.Node, error) {
+	query, qerr := SecurityCheck(ctx, sq.Select(jobColumns...).From("node"))
+	if qerr != nil {
+		return nil, qerr
+	}
+
+	for _, f := range filters {
+		if f.Hostname != nil {
+			query = buildStringCondition("node.hostname", f.Hostname, query)
+		}
+		if f.Cluster != nil {
+			query = buildStringCondition("node.cluster", f.Cluster, query)
+		}
+		if f.NodeState != nil {
+			query = query.Where("node.node_state = ?", f.NodeState)
+		}
+		if f.HealthState != nil {
+			query = query.Where("node.health_state = ?", f.HealthState)
+		}
+	}
+
+	rows, err := query.RunWith(r.stmtCache).Query()
+	if err != nil {
+		queryString, queryVars, _ := query.ToSql()
+		log.Errorf("Error while running query '%s' %v: %v", queryString, queryVars, err)
+		return nil, err
+	}
+
+	nodes := make([]*schema.Node, 0, 50)
+	for rows.Next() {
+		node := schema.Node{}
+
+		if err := rows.Scan(&node.Hostname, &node.Cluster, &node.SubCluster,
+			&node.NodeState, &node.HealthState); err != nil {
+			rows.Close()
+			log.Warn("Error while scanning rows (Nodes)")
+			return nil, err
+		}
+		nodes = append(nodes, &node)
+	}
+
+	return nodes, nil
 }
 
 func (r *NodeRepository) ListNodes(cluster string) ([]*schema.Node, error) {