the beginning of smarter encoding and decoding of prefixes

Author: Benjamin Forster

index.js

@@ -37,7 +37,8 @@ function Graph (storage, key, opts) {
   if (!opts) opts = {}
   this.db = hyperdb(storage, key, opts)
   this._prefixes = Object.assign({}, opts.prefixes || constants.DEFAULT_PREFIXES)
-  this._prefixes._ = opts.base || constants.DEFAULT_BASE
+  this._basename = opts.base || constants.DEFAULT_BASE
+  this._prefixes._ = this._basename
   this._indexes = opts.index === 'tri'
     ? constants.HEXSTORE_INDEXES_REDUCED
     : constants.HEXSTORE_INDEXES
@@ -61,10 +62,11 @@ function Graph (storage, key, opts) {
 inherits(Graph, events.EventEmitter)
 
 Graph.prototype._onNew = function (cb) {
+  this._version = pkg.version
   const metadata = [
     ['@version', pkg.version],
     ['@index', Object.keys(this._indexes).length === 3 ? 'tri' : 'hex'],
-    ['@name', this._prefixes._]
+    ['@name', this._basename]
   ]
   Object.keys(this._prefixes).forEach((key) => {
     if (key !== '_') {
@@ -95,8 +97,8 @@ Graph.prototype.addPrefix = function (prefix, uri, cb) {
 }
 
 Graph.prototype.getStream = function (triple, opts) {
-  const stream = this.db.createReadStream(this._createQuery(triple))
-  return stream.pipe(new HyperdbReadTransform(this.db, this._prefixes, opts))
+  const stream = this.db.createReadStream(this._createQuery(triple, { encode: (!opts || opts.encode === undefined) ? true : opts.encode }))
+  return stream.pipe(new HyperdbReadTransform(this.db, this._basename, opts))
 }
 
 Graph.prototype.get = function (triple, opts, callback) {
@@ -153,8 +155,7 @@ Graph.prototype.searchStream = function (query, options) {
   } else if (!Array.isArray(query)) {
     query = [ query ]
   }
-  const plannedQuery = planner(query)
-
+  const plannedQuery = planner(query, this._prefixes)
   var streams = plannedQuery.map((triple, i) => {
     const limit = (options && i === plannedQuery.length - 1) ? options.limit : undefined
     return new JoinStream({
@@ -217,7 +218,7 @@ Graph.prototype._createQuery = function (pattern, options) {
   var types = utils.typesFromPattern(pattern)
   var preferedIndex = options && options.index
   var index = this._findIndex(types, preferedIndex)
-  const encodedTriple = utils.encodeTriple(pattern, this._prefixes)
+  const encodedTriple = utils.encodeTriple(pattern, options.encode ? this._prefixes : { _: this._basename })
   var key = utils.encodeKey(index, encodedTriple)
   return key
 }

lib/HyperdbReadTransform.js

@@ -2,13 +2,13 @@ const Transform = require('readable-stream').Transform
 const inherits = require('inherits')
 const utils = require('./utils')
 
-function HyperdbReadTransform (db, prefixes, options) {
+function HyperdbReadTransform (db, basename, options) {
   if (!(this instanceof HyperdbReadTransform)) {
     return new HyperdbReadTransform(db, options)
   }
   var opts = options || {}
   this.db = db
-  this._prefixes = prefixes
+  this._prefixes = { _: basename }
   this._finished = false
   this._count = 0
   this._filter = opts.filter

lib/JoinStream.js

@@ -16,12 +16,12 @@ function JoinStream (options) {
   this.matcher = matcher(options.triple)
   this.mask = queryMask(options.triple)
   this.maskUpdater = maskUpdater(options.triple)
-  this.limit = options && options.limit
+  this.limit = options.limit
   this._limitCounter = 0
   this.db = options.db
   this._ended = false
-  this.filter = options && options.filter
-  this.offset = options && options.offset
+  this.filter = options.filter
+  this.offset = options.offset
 
   this.once('pipe', (source) => {
     source.on('error', (err) => {
@@ -49,7 +49,11 @@ function JoinStream (options) {
     }
   }
 
-  this._options = { filter: this.filter, offset: this.offset }
+  this._options = {
+    filter: this.filter,
+    offset: this.offset,
+    encode: options.encode ? !!options.encode : false
+  }
 }
 
 inherits(JoinStream, Transform)

lib/planner.js

@@ -1,8 +1,8 @@
 
 const utils = require('./utils')
 
-function planner (query) {
-  if (query.length === 1) return query
+function planner (query, prefixMap) {
+  if (query.length === 1) return [utils.encodeTriple(query[0], prefixMap)]
   // first group queries based on number of variables.
   const solved = new Set()
   var grouped = query.reduce((ordered, q) => {
@@ -24,7 +24,7 @@ function planner (query) {
     return ordered
   }, [])
   // then order vars > 1 by if they occur in
-  const orderedQueries = grouped[1] ? grouped[1].map(v => v.query) : []
+  const orderedQueries = grouped[1] ? grouped[1].map(v => utils.encodeTriple(v.query, prefixMap)) : []
 
   for (let i = 2; i < grouped.length; i++) {
     if (grouped[i] === undefined) continue
@@ -53,7 +53,7 @@ function planner (query) {
         return 0
       })
       const next = grouped[i].shift()
-      orderedQueries.push(next.query)
+      orderedQueries.push(utils.encodeTriple(next.query, prefixMap))
       next.names.forEach(n => solved.add(n))
     }
   }

lib/utils.js

@@ -54,7 +54,6 @@ function unescapeKeyValue (value, prefixMap) {
 }
 
 function encodeTriple (triple, prefixMap) {
-  // var newTriple = Object.assign({}, triple)
   spo.forEach((key) => {
     if (triple.hasOwnProperty(key)) {
       triple[key] = escapeKeyValue(triple[key], prefixMap)

test/basic.spec.js

@@ -118,9 +118,8 @@ describe('hypergraph', function () {
   })
   context('when loading db that already exists', () => {
     it('does not add new metadata', (done) => {
-      tmp.dir(function (err, dir, cleanupCallback) {
+      tmp.dir({ unsafeCleanup: true }, function (err, dir, cleanupCallback) {
         if (err) return done(err)
-        console.log('Dir: ', dir)
         const dbDir = path.join(dir, 'test.db')
         // create new hyperdb
         const hyper = hyperdb(dbDir)
@@ -138,7 +137,7 @@ describe('hypergraph', function () {
           db.on('ready', () => {
             db.db.get('@version', (err, nodes) => {
               expect(nodes).to.eql(null)
-              done(err)
+              finish(err)
             })
           })
           db.on('error', finish)