Tokyo Cabinet BSON store prototype

gistfile1.sls

(load "NuTokyo")
(load "NuMongoDB") ;; for BSON wrapper

;; Tokyo Cabinet BSON document store example.
;; stores documents in a HashDB and builds indexes using BTreeDBs.

;; clear all files
(system "rm hashdb; rm permalinkindexdb; rm dateindexdb")

;; hashdb is used to store all objects
(set hashdb ((TokyoHashDB alloc) init))
(hashdb openWithDatabaseName:"hashdb" modes:(array "HDBOWRITER" "HDBOCREAT"))

;; we will index places by permalink and town
(set permalinkindexdb ((TokyoBTreeDB alloc) init))
(set comparatorBSON (NuBSON bsonWithList:(list permalink:1 town:1)))
(permalinkindexdb setComparator:(NuBSONComparator comparatorWithBSONSpecification:comparatorBSON))
(permalinkindexdb openWithDatabaseName:"permalinkindexdb" modes:(array "BDBOWRITER" "BDBOCREAT"))

;; we will index places by date added
(set dateindexdb ((TokyoBTreeDB alloc) init))
(set dateComparatorBSON (NuBSON bsonWithList:(list date:-1)))
(set dateComparator (NuBSONComparator comparatorWithBSONSpecification:dateComparatorBSON))
(dateindexdb setComparator:dateComparator)
(dateindexdb openWithDatabaseName:"dateindexdb" modes:(array "BDBOWRITER" "BDBOCREAT"))

;; load archived place data from a BSON file exported from MongoDB
(set placedata (NSData dataWithContentsOfFile:"places.bson"))
(set places (NuBSON bsonArrayWithData:placedata))
(places each:
        (do (place)
            ;; add place object to main table
            (set _id (place _id:))
            (hashdb setData:(place dataRepresentation)
                    forKey:(_id dataRepresentation))
            
            ;; add place to permalink index
            (set indexKey (dict town:(place town_id:) permalink:(place permalink:)))
            (permalinkindexdb setData:(_id dataRepresentation)
                 forKey:((NuBSON bsonWithDictionary:indexKey) dataRepresentation))
            
            ;; add place to date index
            (set indexKey (dict date:(place created_at:)))
            (dateindexdb setData:(_id dataRepresentation)
                 forKey:((NuBSON bsonWithDictionary:indexKey) dataRepresentation))))

;; now use the date index to traverse places added over range of dates

(set beginKey
     ((NuBSON bsonWithDictionary:(dict date:(NSDate dateWithNaturalLanguageString:"May 1, 2010")))
      dataRepresentation))

(set endKey
     ((NuBSON bsonWithDictionary:(dict date:(NSDate dateWithNaturalLanguageString:"April 1, 2010")))
      dataRepresentation))

;; get object ids from the index, use them to look up actual objects
(set dataInRange (dateindexdb dataFromKey:beginKey toKey:endKey))
(dataInRange each:
     (do (idData)
         (set objectData (hashdb dataForKey:idData))
         (set object (NuBSON bsonWithData:objectData))
         (puts (((object dictionaryValue) description)))))

(dateindexdb close)
(permalinkindexdb close)
(hashdb close)
(puts "DONE")