github.com/m3db/m3@v1.5.0/src/dbnode/namespace/map.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 namespace
    22  
    23  import (
    24  	"errors"
    25  	"fmt"
    26  
    27  	xerrors "github.com/m3db/m3/src/x/errors"
    28  	"github.com/m3db/m3/src/x/ident"
    29  )
    30  
    31  var (
    32  	errEmptyMetadatas = errors.New("no namespace metadata provided")
    33  )
    34  
    35  type nsMap struct {
    36  	namespaces *metadataMap
    37  	ids        []ident.ID
    38  	metadatas  []Metadata
    39  }
    40  
    41  // NewMap returns a new registry containing provided metadatas,
    42  // providing a consistent order.
    43  func NewMap(metadatas []Metadata) (Map, error) {
    44  	if len(metadatas) == 0 {
    45  		return nil, errEmptyMetadatas
    46  	}
    47  
    48  	var (
    49  		ns          = newMetadataMap(metadataMapOptions{})
    50  		ids         = make([]ident.ID, 0, len(metadatas))
    51  		nsMetadatas = make([]Metadata, 0, len(metadatas))
    52  		multiErr    xerrors.MultiError
    53  	)
    54  	for _, m := range metadatas {
    55  		id := m.ID()
    56  		ids = append(ids, id)
    57  		nsMetadatas = append(nsMetadatas, m)
    58  
    59  		if _, ok := ns.Get(id); ok {
    60  			multiErr = multiErr.Add(fmt.Errorf(
    61  				"namespace ids must be unique, duplicate found: %v", id.String()))
    62  		}
    63  		ns.Set(id, m)
    64  	}
    65  
    66  	if err := multiErr.FinalError(); err != nil {
    67  		return nil, err
    68  	}
    69  
    70  	return &nsMap{
    71  		namespaces: ns,
    72  		ids:        ids,
    73  		metadatas:  nsMetadatas,
    74  	}, nil
    75  }
    76  
    77  func (r *nsMap) Get(namespace ident.ID) (Metadata, error) {
    78  	metadata, ok := r.namespaces.Get(namespace)
    79  	if !ok {
    80  		return nil, fmt.Errorf("unable to find namespace (%v) in registry", namespace.String())
    81  	}
    82  	return metadata, nil
    83  }
    84  
    85  func (r *nsMap) IDs() []ident.ID {
    86  	return r.ids
    87  }
    88  
    89  func (r *nsMap) Metadatas() []Metadata {
    90  	return r.metadatas
    91  }
    92  
    93  func (r *nsMap) Equal(value Map) bool {
    94  	// short circuit ptr equals
    95  	if value == r {
    96  		return true
    97  	}
    98  
    99  	ourMds := r.Metadatas()
   100  	theirMds := value.Metadatas()
   101  	if len(ourMds) != len(theirMds) {
   102  		return false
   103  	}
   104  
   105  	// O(n**2) test, not a big deal because this is only 3-5 elements
   106  	for _, om := range ourMds {
   107  		found := false
   108  		for _, tm := range theirMds {
   109  			if om.Equal(tm) {
   110  				found = true
   111  				break
   112  			}
   113  		}
   114  		if !found {
   115  			return false
   116  		}
   117  	}
   118  
   119  	return true
   120  }