Add import utils

src/common/export.js

@@ -1,9 +1,10 @@
 'use strict'
 
-
-
 const props = {
   item: [
+    'list',
+    'photo',
+    'tag',
     'template'
   ],
 
@@ -25,6 +26,7 @@ const props = {
     'mimetype',
     'orientation',
     'path',
+    'selection',
     'size',
     'template'
   ],

src/common/import.js

@@ -0,0 +1,69 @@
+'use strict'
+
+const ex = require('./export')
+const { expand, open, toList, toValue } = require('./json')
+const { tropy } = require('./ns')
+const { array, map, omit, get } = require('./util')
+
+// Expand JSON-LD and ungroup item graph for backwards compatibility!
+const normalize = async (json) =>
+  array(await expand(json))
+    .flatMap(g =>
+      g['@graph'].map(item =>
+        (tropy.template in item) ? item : {
+          [tropy.template]: g[tropy.template],
+          ...item
+        }))
+
+
+const toFirstValue = (_, values) =>
+  toValue(values[0])
+
+const getMetadata = (data, skip = ['@id', '@type']) =>
+  map(omit(data, skip), toFirstValue)
+
+const getPhoto = (data) => ({
+  data: getMetadata(data, props.photo),
+  id: get(data, ['@id', 0]),
+  template: get(data, [tropy.template, 0, '@id']),
+  type: get(data, ['@type', 0])
+})
+
+function *eachItem(graph) {
+  for (let data of graph) {
+    yield ({
+      data: getMetadata(data, props.item),
+      id: get(data, ['@id', 0]),
+      lists: (data[tropy.list] || []).map(toValue),
+      photos: toList(data[tropy.photo]).map(getPhoto),
+      tags: (data[tropy.tag] || []).map(toValue),
+      template: get(data, [tropy.template, 0, '@id']),
+      type: get(data, ['@type', 0])
+    })
+
+  }
+}
+
+const props = {
+  item: [
+    '@id',
+    '@type',
+    ...ex.props.item.map(prop => tropy[prop])
+  ],
+
+  photo: [
+    '@id',
+    '@type',
+    ...ex.props.photo.map(prop => tropy[prop])
+  ]
+}
+
+
+module.exports = {
+  eachItem,
+  normalize,
+
+  async open(...args) {
+    return normalize(await open(...args))
+  }
+}

src/common/json.js

@@ -2,6 +2,7 @@
 
 const { readFile, writeFile } = require('fs').promises
 const { rdfs } = require('./ns')
+const { array } = require('./util')
 
 // NB: load jsonld module on demand, because it's huge.
 const jsonld = {
@@ -48,6 +49,10 @@ const write = async (file, data, {
   return writeFile(file, JSON.stringify(data, null, indent), opts)
 }
 
+const toList = (node) =>
+  array(node)
+    .flatMap(container => container['@list'] || container)
+
 const toValue = (node) =>
   node['@id'] ?
     { type: rdfs.Class, text: node['@id'] } :
@@ -65,5 +70,6 @@ module.exports = {
   parse,
   write,
 
+  toList,
   toValue
 }