github.imxd.top/hashicorp/consul@v1.4.5/agent/consul/state/schema.go (about)

     1  package state
     2  
     3  import (
     4  	"fmt"
     5  
     6  	"github.com/hashicorp/go-memdb"
     7  )
     8  
     9  // schemaFn is an interface function used to create and return
    10  // new memdb schema structs for constructing an in-memory db.
    11  type schemaFn func() *memdb.TableSchema
    12  
    13  // schemas is used to register schemas with the state store.
    14  var schemas []schemaFn
    15  
    16  // registerSchema registers a new schema with the state store. This should
    17  // get called at package init() time.
    18  func registerSchema(fn schemaFn) {
    19  	schemas = append(schemas, fn)
    20  }
    21  
    22  // stateStoreSchema is used to return the combined schema for
    23  // the state store.
    24  func stateStoreSchema() *memdb.DBSchema {
    25  	// Create the root DB schema
    26  	db := &memdb.DBSchema{
    27  		Tables: make(map[string]*memdb.TableSchema),
    28  	}
    29  
    30  	// Add the tables to the root schema
    31  	for _, fn := range schemas {
    32  		schema := fn()
    33  		if _, ok := db.Tables[schema.Name]; ok {
    34  			panic(fmt.Sprintf("duplicate table name: %s", schema.Name))
    35  		}
    36  		db.Tables[schema.Name] = schema
    37  	}
    38  	return db
    39  }
    40  
    41  // indexTableSchema returns a new table schema used for tracking various indexes
    42  // for the Raft log.
    43  func indexTableSchema() *memdb.TableSchema {
    44  	return &memdb.TableSchema{
    45  		Name: "index",
    46  		Indexes: map[string]*memdb.IndexSchema{
    47  			"id": &memdb.IndexSchema{
    48  				Name:         "id",
    49  				AllowMissing: false,
    50  				Unique:       true,
    51  				Indexer: &memdb.StringFieldIndex{
    52  					Field:     "Key",
    53  					Lowercase: true,
    54  				},
    55  			},
    56  		},
    57  	}
    58  }
    59  
    60  func init() {
    61  	registerSchema(indexTableSchema)
    62  }