fix(JSONReader): Add basic JSON reader as vtkAlgo

Author: jourdain

Sources/IO/Misc/JSONReader/index.js

@@ -0,0 +1,76 @@
+import macro from 'vtk.js/Sources/macro';
+
+// ----------------------------------------------------------------------------
+// vtkJSONReader methods
+// ----------------------------------------------------------------------------
+
+function vtkJSONReader(publicAPI, model) {
+  // Set our className
+  model.classHierarchy.push('vtkJSONReader');
+
+  // Internal method to fetch Array
+  function fetchData(url, option = {}) {
+    return model.dataAccessHelper.fetchText(publicAPI, url, option);
+  }
+
+  // Set DataSet url
+  publicAPI.setUrl = (url, option = {}) => {
+    model.url = url;
+
+    // Fetch metadata
+    return publicAPI.loadData(option);
+  };
+
+  // Fetch the actual data arrays
+  publicAPI.loadData = (option = {}) =>
+    fetchData(model.url, option).then(publicAPI.parseAsText);
+
+  publicAPI.parseAsText = (content) => {
+    if (!content) {
+      return false;
+    }
+    model.data = JSON.parse(content);
+    publicAPI.modified();
+    return true;
+  };
+
+  publicAPI.requestData = (inData, outData) => {
+    outData[0] = model.data;
+  };
+
+  // return Busy state
+  publicAPI.isBusy = () => false;
+
+  publicAPI.getNumberOfOutputPorts = () => model.numberOfOutputs;
+}
+
+// ----------------------------------------------------------------------------
+// Object factory
+// ----------------------------------------------------------------------------
+
+const DEFAULT_VALUES = {
+  // url: null,
+};
+
+// ----------------------------------------------------------------------------
+
+export function extend(publicAPI, model, initialValues = {}) {
+  Object.assign(model, DEFAULT_VALUES, initialValues);
+
+  // Build VTK API
+  macro.obj(publicAPI, model);
+  macro.get(publicAPI, model, ['url']);
+  macro.algo(publicAPI, model, 0, 1);
+  macro.event(publicAPI, model, 'busy');
+
+  // Object methods
+  vtkJSONReader(publicAPI, model);
+}
+
+// ----------------------------------------------------------------------------
+
+export const newInstance = macro.newInstance(extend, 'vtkJSONReader');
+
+// ----------------------------------------------------------------------------
+
+export default { newInstance, extend };

Sources/IO/Misc/index.js

@@ -1,10 +1,12 @@
 import vtkElevationReader from './ElevationReader';
+import vtkJSONReader from './JSONReader';
 import vtkMTLReader from './MTLReader';
 import vtkOBJReader from './OBJReader';
 import vtkPDBReader from './PDBReader';
 
 export default {
   vtkElevationReader,
+  vtkJSONReader,
   vtkMTLReader,
   vtkOBJReader,
   vtkPDBReader,