first steps towards hyperdb v3

Author: Benjamin Forster

index.js

@@ -19,9 +19,10 @@ const Transform = stream.Transform
 const PassThrough = stream.PassThrough
 
 // temporarily augment hyperdb prototype to include createReadStream
-if (!hyperdb.createReadStream) {
-  attachCreateReadStream(hyperdb)
-}
+// if (!hyperdb.createReadStream) {
+//   console.log('USING CUSTOM createReadStream')
+//   attachCreateReadStream(hyperdb)
+// }
 
 function Graph (storage, key, opts) {
   if (!(this instanceof Graph)) return new Graph(storage, key, opts)
@@ -131,7 +132,7 @@ Graph.prototype.v = (name) => new Variable(name)
 function returnValueAsString (cb) {
   return (err, nodes) => {
     if (err) return cb(err)
-    if (!nodes) return cb(null, null)
+    if (!nodes || nodes.length === 0) return cb(null, null)
     cb(null, nodes[0].value.toString())
   }
 }

lib/HyperdbReadTransform.js

@@ -4,12 +4,11 @@ const utils = require('./utils')
 
 function HyperdbReadTransform (db, basename, options) {
   if (!(this instanceof HyperdbReadTransform)) {
-    return new HyperdbReadTransform(db, options)
+    return new HyperdbReadTransform(db, basename, options)
   }
   var opts = options || {}
   this.db = db
   this._prefixes = { _: basename }
-  this._finished = false
   this._count = 0
   this._filter = opts.filter
   this._offset = opts.offset || 0
@@ -25,13 +24,6 @@ function HyperdbReadTransform (db, basename, options) {
 inherits(HyperdbReadTransform, Transform)
 
 HyperdbReadTransform.prototype._transform = function transform (nodes, encoding, done) {
-  if (this._finished) return done()
-  if (this._limit && this._count >= this._limit) {
-    this.push(null)
-    this._sources.forEach(source => source.destroy())
-    this._finished = true
-    return
-  }
   var value = nodes[0].value && JSON.parse(nodes[0].value.toString())
   if (value === null) return done()
   value = Object.assign(value, utils.decodeKey(nodes[0].key, this._prefixes))
@@ -40,8 +32,16 @@ HyperdbReadTransform.prototype._transform = function transform (nodes, encoding,
       this.push(value)
     }
     this._count++
+    if (this._limit && this._count >= this._limit) {
+      this.end()
+    }
   }
   done()
 }
 
+HyperdbReadTransform.prototype._flush = function (done) {
+  this._sources.forEach(source => source.destroy())
+  done()
+}
+
 module.exports = HyperdbReadTransform

lib/utils.js

@@ -10,7 +10,7 @@ const tripleAliasMap = {
 }
 
 function isNewDatabase (db) {
-  return !(db._writers.length > 1 || db._writers[0].feed.length > 0)
+  return !(db.feeds.length > 1 || db.feeds[0].length > 0)
 }
 
 function put (db, data, callback) {

package.json

@@ -11,7 +11,7 @@
     "url": "https://github.com/e-e-e/hyper-graph-db/issues"
   },
   "dependencies": {
-    "hyperdb": "^2.0.0",
+    "hyperdb": "3.0.0-0",
     "lru": "^3.1.0",
     "pump": "^3.0.0",
     "readable-stream": "^2.3.3",

test/basic.spec.js

@@ -136,7 +136,7 @@ describe('hypergraph', function () {
           db = hypergraph(dbDir)
           db.on('ready', () => {
             db.db.get('@version', (err, nodes) => {
-              expect(nodes).to.eql(null)
+              expect(nodes).to.eql([])
               finish(err)
             })
           })