// CreateIterator creates a remote streaming iterator.
func (ic *remoteIteratorCreator) CreateIterator(opt influxql.IteratorOptions) (influxql.Iterator, error) {
conn, err := ic.dialer.DialNode(ic.nodeID)
if err != nil {
return nil, err
}
if err := func() error {
// Write request.
if err := EncodeTLV(conn, createIteratorRequestMessage, &CreateIteratorRequest{
ShardIDs: ic.shardIDs,
Opt: opt,
}); err != nil {
return err
}
// Read the response.
var resp CreateIteratorResponse
if _, err := DecodeTLV(conn, &resp); err != nil {
return err
} else if resp.Err != nil {
return err
}
return nil
}(); err != nil {
conn.Close()
return nil, err
}
return influxql.NewReaderIterator(conn)
}
// Ensure iterator can be encoded and decoded over a byte stream.
func TestIterator_EncodeDecode(t *testing.T) {
var buf bytes.Buffer
// Create an iterator with several points & stats.
itr := &FloatIterator{
Points: []influxql.FloatPoint{
{Name: "cpu", Tags: ParseTags("host=A"), Time: 0, Value: 0},
{Name: "mem", Tags: ParseTags("host=B"), Time: 1, Value: 10},
},
stats: influxql.IteratorStats{
SeriesN: 2,
PointN: 0,
},
}
// Encode to the buffer.
enc := influxql.NewIteratorEncoder(&buf)
enc.StatsInterval = 100 * time.Millisecond
if err := enc.EncodeIterator(itr); err != nil {
t.Fatal(err)
}
// Decode from the buffer.
dec, err := influxql.NewReaderIterator(&buf, influxql.Float, itr.Stats())
if err != nil {
t.Fatal(err)
}
// Initial stats should exist immediately.
fdec := dec.(influxql.FloatIterator)
if stats := fdec.Stats(); !reflect.DeepEqual(stats, influxql.IteratorStats{SeriesN: 2, PointN: 0}) {
t.Fatalf("unexpected stats(initial): %#v", stats)
}
// Read both points.
if p, err := fdec.Next(); err != nil {
t.Fatalf("unexpected error(0): %#v", err)
} else if !reflect.DeepEqual(p, &influxql.FloatPoint{Name: "cpu", Tags: ParseTags("host=A"), Time: 0, Value: 0}) {
t.Fatalf("unexpected point(0); %#v", p)
}
if p, err := fdec.Next(); err != nil {
t.Fatalf("unexpected error(1): %#v", err)
} else if !reflect.DeepEqual(p, &influxql.FloatPoint{Name: "mem", Tags: ParseTags("host=B"), Time: 1, Value: 10}) {
t.Fatalf("unexpected point(1); %#v", p)
}
if p, err := fdec.Next(); err != nil {
t.Fatalf("unexpected error(eof): %#v", err)
} else if p != nil {
t.Fatalf("unexpected point(eof); %#v", p)
}
}