Backend: implement alerting query (#847)

* Unit tests for backend

* minor change

* Implemented querNumericItems in backend

* Added query type

* Set alerting to true

* Return TimeSeries from History

* Updated alerting feature

* Fix params marshal error

* Fix params more

* Update zabbixAPIConnector.js

* Numbers, I guess

* Params Output Type

* Output marshaling

* Unmarshal and decoder error catch

* HistoryPoint and Unmarshal fixes

* Unmarshal to History

* Revert "Update zabbixAPIConnector.js"

This reverts commit e0ffdff.

* Fix unmarshaling for real

* Time range integer

* Use more zabbix.Items

* Update response_models.go

* Update zabbix_api.go

* Update models.go

* Update zabbix_api.go

* Tests

* Adding more unit tests and cleaning up additional logging

* Make history request param a pointer

* Actually store datasource in cache

* Debug logs and timings

* Handle panics gracefully

* Updated Regex filter parsing

* Removed must compile

* Clean up regex filter

go.mod

@@ -13,6 +13,7 @@ require (
 	github.com/kr/pretty v0.1.0 // indirect
 	github.com/patrickmn/go-cache v2.1.0+incompatible
 	github.com/pkg/errors v0.8.1 // indirect
+	github.com/stretchr/testify v1.3.0
 	golang.org/x/net v0.0.0-20190724013045-ca1201d0de80
 	golang.org/x/sys v0.0.0-20191010194322-b09406accb47 // indirect
 	golang.org/x/text v0.3.2 // indirect

pkg/datasource.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"runtime/debug"
 
 	simplejson "github.com/bitly/go-simplejson"
 	"github.com/grafana/grafana_plugin_model/go/datasource"
@@ -27,7 +28,16 @@ func (b *ZabbixBackend) newZabbixDatasource() *ZabbixDatasource {
 
 // Query receives requests from the Grafana backend. Requests are filtered by query type and sent to the
 // applicable ZabbixDatasource.
-func (b *ZabbixBackend) Query(ctx context.Context, tsdbReq *datasource.DatasourceRequest) (*datasource.DatasourceResponse, error) {
+func (b *ZabbixBackend) Query(ctx context.Context, tsdbReq *datasource.DatasourceRequest) (resp *datasource.DatasourceResponse, _e error) {
+	defer func() {
+		if r := recover(); r != nil {
+			pErr, _ := r.(error)
+			b.logger.Error("Fatal error in Zabbix Plugin Backend", "Error", pErr)
+			b.logger.Error(string(debug.Stack()))
+			resp = BuildErrorResponse(fmt.Errorf("Unrecoverable error in grafana-zabbix plugin backend"))
+		}
+	}()
+
 	zabbixDs := b.getCachedDatasource(tsdbReq)
 
 	queryType, err := GetQueryType(tsdbReq)
@@ -37,13 +47,17 @@ func (b *ZabbixBackend) Query(ctx context.Context, tsdbReq *datasource.Datasourc
 
 	switch queryType {
 	case "zabbixAPI":
-		return zabbixDs.ZabbixAPIQuery(ctx, tsdbReq)
+		resp, err = zabbixDs.ZabbixAPIQuery(ctx, tsdbReq)
+	case "query":
+		resp, err = zabbixDs.queryNumericItems(ctx, tsdbReq)
 	case "connectionTest":
-		return zabbixDs.TestConnection(ctx, tsdbReq)
+		resp, err = zabbixDs.TestConnection(ctx, tsdbReq)
 	default:
 		err = errors.New("Query not implemented")
 		return BuildErrorResponse(err), nil
 	}
+
+	return
 }
 
 func (b *ZabbixBackend) getCachedDatasource(tsdbReq *datasource.DatasourceRequest) *ZabbixDatasource {
@@ -59,7 +73,10 @@ func (b *ZabbixBackend) getCachedDatasource(tsdbReq *datasource.DatasourceReques
 		dsInfo := tsdbReq.GetDatasource()
 		b.logger.Debug(fmt.Sprintf("Datasource cache miss (Org %d Id %d '%s' %s)", dsInfo.GetOrgId(), dsInfo.GetId(), dsInfo.GetName(), dsInfoHash))
 	}
-	return b.newZabbixDatasource()
+
+	ds := b.newZabbixDatasource()
+	b.datasourceCache.Set(dsInfoHash, ds)
+	return ds
 }
 
 // GetQueryType determines the query type from a query or list of queries
@@ -104,3 +121,15 @@ func BuildErrorResponse(err error) *datasource.DatasourceResponse {
 		},
 	}
 }
+
+// BuildMetricsResponse builds a response object using a given TimeSeries array
+func BuildMetricsResponse(metrics []*datasource.TimeSeries) (*datasource.DatasourceResponse, error) {
+	return &datasource.DatasourceResponse{
+		Results: []*datasource.QueryResult{
+			&datasource.QueryResult{
+				RefId:  "zabbixMetrics",
+				Series: metrics,
+			},
+		},
+	}, nil
+}

pkg/datasource_test.go

@@ -78,6 +78,11 @@ func TestZabbixBackend_getCachedDatasource(t *testing.T) {
 
 			// Only checking the authToken, being the easiest value to, and guarantee equality for
 			assert.Equal(t, tt.want.authToken, got.authToken)
+
+			// Ensure the datasource is in the cache
+			cacheds, ok := tt.cache.Get(HashDatasourceInfo(tt.request.GetDatasource()))
+			assert.Equal(t, true, ok)
+			assert.Equal(t, got, cacheds)
 		})
 	}
 }

pkg/models.go

@@ -1,5 +1,10 @@
 package main
 
+import (
+	"encoding/json"
+	"fmt"
+)
+
 type connectionTestResponse struct {
 	ZabbixVersion     string              `json:"zabbixVersion"`
 	DbConnectorStatus *dbConnectionStatus `json:"dbConnectorStatus"`
@@ -9,3 +14,77 @@ type dbConnectionStatus struct {
 	DsType string `json:"dsType"`
 	DsName string `json:"dsName"`
 }
+
+type requestModel struct {
+	Target queryRequest `json:"target,omitempty"`
+}
+
+type queryRequest struct {
+	Method string       `json:"method,omitempty"`
+	Params zabbixParams `json:"params,omitempty"`
+}
+
+type zabbixParamOutput struct {
+	Mode   string
+	Fields []string
+}
+
+func (p *zabbixParamOutput) MarshalJSON() ([]byte, error) {
+	if p.Mode != "" {
+		return json.Marshal(p.Mode)
+	}
+
+	return json.Marshal(p.Fields)
+}
+
+func (p *zabbixParamOutput) UnmarshalJSON(data []byte) error {
+	if p == nil {
+		return fmt.Errorf("zabbixParamOutput: UnmarshalJSON on nil pointer")
+	}
+
+	var strArray []string
+	err := json.Unmarshal(data, &strArray)
+	if err == nil {
+		p.Fields = strArray
+		return nil
+	}
+
+	var str string
+	err = json.Unmarshal(data, &str)
+	if err == nil {
+		p.Mode = str
+		return nil
+	}
+
+	return fmt.Errorf("Unsupported type: %w", err)
+
+}
+
+type zabbixParams struct {
+	Output    *zabbixParamOutput `json:"output,omitempty"`
+	SortField string             `json:"sortfield,omitempty"`
+	SortOrder string             `json:"sortorder,omitempty"`
+	Filter    map[string][]int   `json:"filter,omitempty"`
+
+	// Login
+	User     string `json:"user,omitempty"`
+	Password string `json:"password,omitempty"`
+
+	// Item GET
+	WebItems    bool     `json:"webitems,omitempty"`
+	SelectHosts []string `json:"selectHosts,omitempty"`
+	ItemIDs     []string `json:"itemids,omitempty"`
+	GroupIDs    []string `json:"groupids,omitempty"`
+	HostIDs     []string `json:"hostids,omitempty"`
+	AppIDs      []string `json:"applicationids,omitempty"`
+
+	// Host Group GET
+	RealHosts bool `json:"real_hosts,omitempty"`
+
+	// History GET
+	History *int `json:"history,omitempty,string"`
+
+	// History/Trends GET
+	TimeFrom int64 `json:"time_from,omitempty"`
+	TimeTill int64 `json:"time_till,omitempty"`
+}

pkg/models_test.go

@@ -0,0 +1,60 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_zabbixParamOutput(t *testing.T) {
+	tests := []struct {
+		name  string
+		input zabbixParams
+		want  string
+	}{
+		{
+			name: "Mode extend",
+			input: zabbixParams{
+				Output: &zabbixParamOutput{
+					Mode: "extend",
+				},
+				GroupIDs: []string{"test1", "test2"},
+			},
+			want: `{ "output": "extend", "groupids": ["test1", "test2"] }`,
+		},
+		{
+			name: "Fields",
+			input: zabbixParams{
+				Output: &zabbixParamOutput{
+					Fields: []string{"name", "key_", "hostid"},
+				},
+				GroupIDs: []string{"test1", "test2"},
+			},
+			want: `{ "output": ["name", "key_", "hostid"], "groupids": ["test1", "test2"] }`,
+		},
+		{
+			name: "No Output",
+			input: zabbixParams{
+				GroupIDs: []string{"test1", "test2"},
+			},
+			want: `{ "groupids": ["test1", "test2"] }`,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			jsonOut, err := json.Marshal(tt.input)
+			fmt.Printf("Output: %s\n", jsonOut)
+			assert.NoError(t, err)
+			if !assert.JSONEq(t, tt.want, string(jsonOut)) {
+				return
+			}
+
+			objOut := zabbixParams{}
+			err = json.Unmarshal(jsonOut, &objOut)
+			assert.NoError(t, err)
+			assert.Equal(t, tt.input, objOut)
+		})
+	}
+}

pkg/zabbix/response_models.go

@@ -0,0 +1,35 @@
+package zabbix
+
+type Items []Item
+type Item struct {
+	ID        string     `json:"itemid,omitempty"`
+	Key       string     `json:"key_,omitempty"`
+	Name      string     `json:"name,omitempty"`
+	ValueType int        `json:"value_type,omitempty,string"`
+	HostID    string     `json:"hostid,omitempty"`
+	Hosts     []ItemHost `json:"hosts,omitempty"`
+	Status    string     `json:"status,omitempty"`
+	State     string     `json:"state,omitempty"`
+}
+type ItemHost struct {
+	ID   string `json:"hostid,omitempty"`
+	Name string `json:"name,omitempty"`
+}
+
+type Trend []TrendPoint
+type TrendPoint struct {
+	ItemID   string `json:"itemid,omitempty"`
+	Clock    int64  `json:"clock,omitempty,string"`
+	Num      string `json:"num,omitempty"`
+	ValueMin string `json:"value_min,omitempty"`
+	ValueAvg string `json:"value_avg,omitempty"`
+	ValueMax string `json:"value_max,omitempty"`
+}
+
+type History []HistoryPoint
+type HistoryPoint struct {
+	ItemID string  `json:"itemid,omitempty"`
+	Clock  int64   `json:"clock,omitempty,string"`
+	Value  float64 `json:"value,omitempty,string"`
+	NS     int64   `json:"ns,omitempty,string"`
+}