Re enable preview (#508)

* add random-access-page-files

* Revert "disable file preview until caching is sorted"

This reverts commit 4eba2f8.

* re-enable preview test

Author: Karissa

client/js/components/hyperdrive/index.js

@@ -1,11 +1,13 @@
 const hyperdriveRenderer = require('./client.js')
+const noop = function () {}
 
 module.exports = function (state, prev, send) {
   var onclick = (ev, entry) => {
     if (entry.type === 'directory') {
       send('archive:update', {root: entry.name})
       return true
     } else {
+      send('preview:file', {archiveKey: state.archive.key, entry: entry}, noop)
       return false
     }
   }

package.json

@@ -111,6 +111,7 @@
     "nodemailer-postmark-transport": "^1.1.0",
     "pretty-bytes": "^3.0.1",
     "pump": "^1.0.2",
+    "random-access-page-files": "^1.0.1",
     "range-parser": "^1.2.0",
     "relative-date": "^1.1.3",
     "render-data": "^2.2.0",

server/dats.js

@@ -2,6 +2,7 @@ const Archiver = require('hypercore-archiver')
 const mkdirp = require('mkdirp')
 const encoding = require('dat-encoding')
 const hyperdrive = require('hyperdrive')
+const pages = require('random-access-page-files')
 const Swarm = require('discovery-swarm')
 const swarmDefaults = require('datland-swarm-defaults')
 const hyperhttp = require('hyperdrive-http')
@@ -12,7 +13,7 @@ module.exports = Dats
 function Dats (dir) {
   if (!(this instanceof Dats)) return new Dats(dir)
   mkdirp.sync(dir)
-  this.archiver = Archiver({dir: dir, sparse: true})
+  this.archiver = Archiver({dir: dir, sparse: true, storage: pages})
   this.swarm = createSwarm(this.archiver)
   this.drive = hyperdrive(this.archiver.db)
   this.archives = {}
@@ -24,13 +25,15 @@ Dats.prototype.get = function (key, cb) {
   key = encoding.toStr(key)
   var buf = encoding.toBuf(key)
   if (self.archives[key]) return cb(null, self.archives[key])
-  self.archiver.add(buf, {content: false}, function (err) {
+  self.archiver.add(buf, {content: true}, function (err) {
     if (err) return cb(err)
     self.archiver.get(buf, function (err, metadata, content) {
       if (err) return cb(err)
-      var archive = self.drive.createArchive(buf, {metadata: metadata, content: content})
-      self.archives[key] = archive
-      return cb(null, archive)
+      if (content) {
+        var archive = self.drive.createArchive(buf, {metadata: metadata, content: content})
+        self.archives[key] = archive
+        return cb(null, archive)
+      }
     })
   })
 }