github.com/weaviate/weaviate@v1.24.6/adapters/repos/db/lsmkv/cursor_segment_map.go (about)

     1  //                           _       _
     2  // __      _____  __ ___   ___  __ _| |_ ___
     3  // \ \ /\ / / _ \/ _` \ \ / / |/ _` | __/ _ \
     4  //  \ V  V /  __/ (_| |\ V /| | (_| | ||  __/
     5  //   \_/\_/ \___|\__,_| \_/ |_|\__,_|\__\___|
     6  //
     7  //  Copyright © 2016 - 2024 Weaviate B.V. All rights reserved.
     8  //
     9  //  CONTACT: hello@weaviate.io
    10  //
    11  
    12  package lsmkv
    13  
    14  import "github.com/weaviate/weaviate/entities/lsmkv"
    15  
    16  type segmentCursorMap struct {
    17  	segment    *segment
    18  	nextOffset uint64
    19  }
    20  
    21  func (s *segment) newMapCursor() *segmentCursorMap {
    22  	return &segmentCursorMap{
    23  		segment: s,
    24  	}
    25  }
    26  
    27  func (sg *SegmentGroup) newMapCursors() ([]innerCursorMap, func()) {
    28  	sg.maintenanceLock.RLock()
    29  	out := make([]innerCursorMap, len(sg.segments))
    30  
    31  	for i, segment := range sg.segments {
    32  		out[i] = segment.newMapCursor()
    33  	}
    34  
    35  	return out, sg.maintenanceLock.RUnlock
    36  }
    37  
    38  func (s *segmentCursorMap) seek(key []byte) ([]byte, []MapPair, error) {
    39  	node, err := s.segment.index.Seek(key)
    40  	if err != nil {
    41  		return nil, nil, err
    42  	}
    43  
    44  	parsed, err := s.parseCollectionNode(nodeOffset{node.Start, node.End})
    45  	// make sure to set the next offset before checking the error. The error
    46  	// could be 'Deleted' which would require that the offset is still advanced
    47  	// for the next cycle
    48  	s.nextOffset = node.End
    49  	if err != nil {
    50  		return parsed.primaryKey, nil, err
    51  	}
    52  
    53  	pairs := make([]MapPair, len(parsed.values))
    54  	for i := range pairs {
    55  		if err := pairs[i].FromBytes(parsed.values[i].value, false); err != nil {
    56  			return nil, nil, err
    57  		}
    58  		pairs[i].Tombstone = parsed.values[i].tombstone
    59  	}
    60  
    61  	return parsed.primaryKey, pairs, nil
    62  }
    63  
    64  func (s *segmentCursorMap) next() ([]byte, []MapPair, error) {
    65  	if s.nextOffset >= s.segment.dataEndPos {
    66  		return nil, nil, lsmkv.NotFound
    67  	}
    68  
    69  	parsed, err := s.parseCollectionNode(nodeOffset{start: s.nextOffset})
    70  	// make sure to set the next offset before checking the error. The error
    71  	// could be 'Deleted' which would require that the offset is still advanced
    72  	// for the next cycle
    73  	s.nextOffset = s.nextOffset + uint64(parsed.offset)
    74  	if err != nil {
    75  		return parsed.primaryKey, nil, err
    76  	}
    77  
    78  	pairs := make([]MapPair, len(parsed.values))
    79  	for i := range pairs {
    80  		if err := pairs[i].FromBytes(parsed.values[i].value, false); err != nil {
    81  			return nil, nil, err
    82  		}
    83  		pairs[i].Tombstone = parsed.values[i].tombstone
    84  	}
    85  
    86  	return parsed.primaryKey, pairs, nil
    87  }
    88  
    89  func (s *segmentCursorMap) first() ([]byte, []MapPair, error) {
    90  	s.nextOffset = s.segment.dataStartPos
    91  
    92  	parsed, err := s.parseCollectionNode(nodeOffset{start: s.nextOffset})
    93  	// make sure to set the next offset before checking the error. The error
    94  	// could be 'Deleted' which would require that the offset is still advanced
    95  	// for the next cycle
    96  	s.nextOffset = s.nextOffset + uint64(parsed.offset)
    97  	if err != nil {
    98  		return parsed.primaryKey, nil, err
    99  	}
   100  
   101  	pairs := make([]MapPair, len(parsed.values))
   102  	for i := range pairs {
   103  		if err := pairs[i].FromBytes(parsed.values[i].value, false); err != nil {
   104  			return nil, nil, err
   105  		}
   106  		pairs[i].Tombstone = parsed.values[i].tombstone
   107  	}
   108  
   109  	return parsed.primaryKey, pairs, nil
   110  }
   111  
   112  func (s *segmentCursorMap) parseCollectionNode(offset nodeOffset) (segmentCollectionNode, error) {
   113  	r, err := s.segment.newNodeReader(offset)
   114  	if err != nil {
   115  		return segmentCollectionNode{}, err
   116  	}
   117  	return ParseCollectionNode(r)
   118  }