github.com/willyham/dosa@v2.3.1-0.20171024181418-1e446d37ee71+incompatible/scan.go (about) 1 // Copyright (c) 2017 Uber Technologies, Inc. 2 // 3 // Permission is hereby granted, free of charge, to any person obtaining a copy 4 // of this software and associated documentation files (the "Software"), to deal 5 // in the Software without restriction, including without limitation the rights 6 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 7 // copies of the Software, and to permit persons to whom the Software is 8 // furnished to do so, subject to the following conditions: 9 // 10 // The above copyright notice and this permission notice shall be included in 11 // all copies or substantial portions of the Software. 12 // 13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 14 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 15 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 16 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 17 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 18 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 19 // THE SOFTWARE. 20 21 package dosa 22 23 import ( 24 "bytes" 25 "fmt" 26 "reflect" 27 28 "github.com/golang/mock/gomock" 29 ) 30 31 // ScanOp represents the scan query 32 type ScanOp struct { 33 pager 34 object DomainObject 35 } 36 37 // NewScanOp returns a new ScanOp instance 38 func NewScanOp(obj DomainObject) *ScanOp { 39 return &ScanOp{object: obj} 40 } 41 42 // Limit sets the number of rows returned per call. Default is 100 43 func (s *ScanOp) Limit(n int) *ScanOp { 44 s.limit = n 45 return s 46 } 47 48 // Offset sets the pagination token. If not set, an empty token would be used. 49 func (s *ScanOp) Offset(token string) *ScanOp { 50 s.token = token 51 return s 52 } 53 54 // Fields list the non-key fields users want to fetch. 55 // PrimaryKey fields are always fetched. 56 func (s *ScanOp) Fields(fields []string) *ScanOp { 57 s.fieldsToRead = fields 58 return s 59 } 60 61 // String satisfies the Stringer interface 62 func (s *ScanOp) String() string { 63 result := &bytes.Buffer{} 64 result.WriteString("ScanOp") 65 addLimitTokenString(result, s.limit, s.token) 66 return result.String() 67 } 68 69 type scanOpMatcher struct { 70 p pager 71 typ reflect.Type 72 } 73 74 // EqScanOp provides a gomock Matcher that matches any ScanOp with a limit, 75 // token, and fields to read that are the same as those specificed by the op argument. 76 func EqScanOp(op *ScanOp) gomock.Matcher { 77 return scanOpMatcher{ 78 p: op.pager, 79 typ: reflect.TypeOf(op.object).Elem(), 80 } 81 } 82 83 // Matches satisfies the gomock.Matcher interface 84 func (m scanOpMatcher) Matches(x interface{}) bool { 85 op, ok := x.(*ScanOp) 86 if !ok { 87 return false 88 } 89 90 return m.p.equals(op.pager) && reflect.TypeOf(op.object).Elem() == m.typ 91 } 92 93 // String satisfies the gomock.Matcher and Stringer interface 94 func (m scanOpMatcher) String() string { 95 return fmt.Sprintf( 96 " is equal to ScanOp with token %s, limit %d, fields %v, and entity type %v", 97 m.p.token, 98 m.p.limit, 99 m.p.fieldsToRead, 100 m.typ) 101 }