Added tests for backend part

pkg/plugin/query_test.go

@@ -0,0 +1,98 @@
+package plugin
+
+import (
+	"testing"
+)
+
+func TestQuery_getQueryURL(t *testing.T) {
+	type fields struct {
+		RefID    string
+		Expr     string
+		MaxLines int
+	}
+	type args struct {
+		rawURL      string
+		queryParams string
+	}
+	tests := []struct {
+		name    string
+		fields  fields
+		args    args
+		want    string
+		wantErr bool
+	}{
+		{
+			name: "empty values",
+			fields: fields{
+				RefID:    "1",
+				Expr:     "",
+				MaxLines: 0,
+			},
+			args: args{
+				rawURL:      "",
+				queryParams: "",
+			},
+			want:    "",
+			wantErr: true,
+		},
+		{
+			name: "has rawURL without params",
+			fields: fields{
+				RefID:    "1",
+				Expr:     "",
+				MaxLines: 0,
+			},
+			args: args{
+				rawURL:      "http://127.0.0.1:9428",
+				queryParams: "",
+			},
+			want:    "http://127.0.0.1:9428/select/logsql/query?limit=1000&query=",
+			wantErr: false,
+		},
+		{
+			name: "has expression and max lines",
+			fields: fields{
+				RefID:    "1",
+				Expr:     "_time:1s",
+				MaxLines: 10,
+			},
+			args: args{
+				rawURL:      "http://127.0.0.1:9428",
+				queryParams: "",
+			},
+			want:    "http://127.0.0.1:9428/select/logsql/query?limit=10&query=_time%3A1s",
+			wantErr: false,
+		},
+		{
+			name: "has expression and max lines, with queryParams",
+			fields: fields{
+				RefID:    "1",
+				Expr:     "_time:1s and syslog",
+				MaxLines: 10,
+			},
+			args: args{
+				rawURL:      "http://127.0.0.1:9428",
+				queryParams: "a=1&b=2",
+			},
+			want:    "http://127.0.0.1:9428/select/logsql/query?a=1&b=2&limit=10&query=_time%3A1s+and+syslog",
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			q := &Query{
+				RefID:    tt.fields.RefID,
+				Expr:     tt.fields.Expr,
+				MaxLines: tt.fields.MaxLines,
+			}
+			got, err := q.getQueryURL(tt.args.rawURL, tt.args.queryParams)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("getQueryURL() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("getQueryURL() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

pkg/plugin/response.go

@@ -2,6 +2,7 @@ package plugin
 
 import (
 	"encoding/json"
+	"fmt"
 	"io"
 
 	"github.com/VictoriaMetrics/metricsql"
@@ -48,7 +49,7 @@ func parseStreamResponse(reader io.Reader) backend.DataResponse {
 		var r Response
 		err := dec.Decode(&r)
 		if err != nil {
-			return newResponseError(err, backend.StatusInternal)
+			return newResponseError(fmt.Errorf("error decode response: %s", err), backend.StatusInternal)
 		}
 
 		for fieldName, value := range r {
@@ -58,7 +59,7 @@ func parseStreamResponse(reader io.Reader) backend.DataResponse {
 			case timeField:
 				getTime, err := utils.GetTime(value)
 				if err != nil {
-					return newResponseError(err, backend.StatusInternal)
+					return newResponseError(fmt.Errorf("error parse time from _time field: %s", err), backend.StatusInternal)
 				}
 				timeFd.Append(getTime)
 			case streamField:

pkg/plugin/response_test.go

@@ -0,0 +1,127 @@
+package plugin
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"reflect"
+	"testing"
+	"time"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+	"github.com/grafana/grafana-plugin-sdk-go/data"
+)
+
+func Test_parseStreamResponse(t *testing.T) {
+	f := func(remoteResp string) io.Reader {
+		return io.NopCloser(bytes.NewBuffer([]byte(remoteResp)))
+	}
+	tests := []struct {
+		name     string
+		reader   func(remoteResp string) io.Reader
+		response string
+		want     func() backend.DataResponse
+	}{
+		{
+			name: "empty response",
+			reader: func(remoteResp string) io.Reader {
+				return io.NopCloser(bytes.NewBuffer([]byte(remoteResp)))
+			},
+			response: "",
+			want: func() backend.DataResponse {
+				labelsField := data.NewFieldFromFieldType(data.FieldTypeJSON, 0)
+				labelsField.Name = gLabelsField
+
+				timeFd := data.NewFieldFromFieldType(data.FieldTypeTime, 0)
+				timeFd.Name = gTimeField
+
+				lineField := data.NewFieldFromFieldType(data.FieldTypeString, 0)
+				lineField.Name = gLineField
+
+				frame := data.NewFrame("", timeFd, lineField, labelsField)
+
+				rsp := backend.DataResponse{}
+				frame.Meta = &data.FrameMeta{}
+				rsp.Frames = append(rsp.Frames, frame)
+
+				return rsp
+			},
+		},
+		{
+			name:     "incorrect response",
+			reader:   f,
+			response: "abcd",
+			want: func() backend.DataResponse {
+				return newResponseError(fmt.Errorf("error decode response: invalid character 'a' looking for beginning of value"), backend.StatusInternal)
+			},
+		},
+		{
+			name:     "incorrect time in the response",
+			reader:   f,
+			response: `{"_time":"acdf"}`,
+			want: func() backend.DataResponse {
+				return newResponseError(fmt.Errorf("error parse time from _time field: cannot parse acdf: cannot parse duration \"acdf\""), backend.StatusInternal)
+			},
+		},
+		{
+			name:     "incorrect time in the response",
+			reader:   f,
+			response: `{"_time":"acdf"}`,
+			want: func() backend.DataResponse {
+				return newResponseError(fmt.Errorf("error parse time from _time field: cannot parse acdf: cannot parse duration \"acdf\""), backend.StatusInternal)
+			},
+		},
+		{
+			name:     "invalid labels in the resposne",
+			reader:   f,
+			response: `{"_time":"2024-02-20", "_stream":"{application=\"logs-benchmark-Apache.log-1708437847\",hostname=}"}`,
+			want: func() backend.DataResponse {
+				return newResponseError(fmt.Errorf("StringExpr: unexpected token \"}\"; want \"string\"; unparsed data: \"}\""), backend.StatusInternal)
+			},
+		},
+		{
+			name:     "correct response line",
+			reader:   f,
+			response: `{"_msg":"123","_stream":"{application=\"logs-benchmark-Apache.log-1708437847\",hostname=\"e28a622d7792\"}","_time":"2024-02-20T14:04:27Z"}`,
+			want: func() backend.DataResponse {
+				labelsField := data.NewFieldFromFieldType(data.FieldTypeJSON, 0)
+				labelsField.Name = gLabelsField
+
+				timeFd := data.NewFieldFromFieldType(data.FieldTypeTime, 0)
+				timeFd.Name = gTimeField
+
+				lineField := data.NewFieldFromFieldType(data.FieldTypeString, 0)
+				lineField.Name = gLineField
+
+				timeFd.Append(time.Date(2024, 02, 20, 14, 04, 27, 0, time.UTC))
+
+				lineField.Append("123")
+
+				labels := data.Labels{
+					"application": "logs-benchmark-Apache.log-1708437847",
+					"hostname":    "e28a622d7792",
+				}
+
+				b, _ := labelsToJSON(labels)
+
+				labelsField.Append(b)
+				frame := data.NewFrame("", timeFd, lineField, labelsField)
+
+				rsp := backend.DataResponse{}
+				frame.Meta = &data.FrameMeta{}
+				rsp.Frames = append(rsp.Frames, frame)
+
+				return rsp
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			r := tt.reader(tt.response)
+			w := tt.want()
+			if got := parseStreamResponse(r); !reflect.DeepEqual(got, w) {
+				t.Errorf("parseStreamResponse() = %#v, want %#v", got, w)
+			}
+		})
+	}
+}