forked from couchbaselabs/tuqtng
-
Notifications
You must be signed in to change notification settings - Fork 0
/
filter.go
74 lines (63 loc) · 1.98 KB
/
filter.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
// Copyright (c) 2013 Couchbase, Inc.
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
// except in compliance with the License. You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software distributed under the
// License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
// either express or implied. See the License for the specific language governing permissions
// and limitations under the License.
package xpipeline
import (
"github.com/couchbaselabs/clog"
"github.com/couchbaselabs/dparval"
"github.com/couchbaselabs/tuqtng/ast"
"github.com/couchbaselabs/tuqtng/misc"
"github.com/couchbaselabs/tuqtng/network"
"github.com/couchbaselabs/tuqtng/query"
)
type Filter struct {
Base *BaseOperator
Expr ast.Expression
}
func NewFilter(expr ast.Expression) *Filter {
return &Filter{
Base: NewBaseOperator(),
Expr: expr,
}
}
func (this *Filter) SetSource(source Operator) {
this.Base.SetSource(source)
}
func (this *Filter) GetChannels() (dparval.ValueChannel, PipelineSupportChannel) {
return this.Base.GetChannels()
}
func (this *Filter) Run(stopChannel misc.StopChannel) {
clog.To(CHANNEL, "filter operator starting")
this.Base.RunOperator(this, stopChannel)
clog.To(CHANNEL, "filter operator finished")
}
func (this *Filter) processItem(item *dparval.Value) bool {
val, err := this.Base.Evaluate(this.Expr, item)
if err != nil {
switch err := err.(type) {
case *dparval.Undefined:
//ignore these
return true
default:
return this.Base.SendError(query.NewError(err, "error evaluating filter"))
}
}
valval := val.Value()
boolVal := ast.ValueInBooleanContext(valval)
switch boolVal := boolVal.(type) {
case bool:
if boolVal {
return this.Base.SendItem(item)
}
}
return true
}
func (this *Filter) afterItems() {}
func (this *Filter) SetQuery(q network.Query) {
this.Base.SetQuery(q)
}