Re-add extensions as top level dir

extensions/ohif-vtk-extension/src/OHIFVTKExtension.js

@@ -0,0 +1,54 @@
+import React, { Component } from 'react';
+import OHIFVTKViewport from './OHIFVTKViewport.js';
+import ToolbarModule from './ToolbarModule.js';
+
+/**
+ * Pass in 'children' to a React component. The purpose of this is to
+ * allow end users of this extension to pass in components which will
+ * be rendered on top of the base components.
+ *
+ * @param WrappedComponent
+ * @param children
+ * @return {function(*): *}
+ */
+function withChildren(WrappedComponent, children) {
+  return function(props) {
+    return <WrappedComponent children={children} { ...props } />;
+  };
+}
+
+// Note: If you are authoring extensions which use stateful libraries (e.g. cornerstone-core, react-redux) as peerDependencies and are also duplicated at the application level, try using 'yalc' to link it to the application, rather than yarn link. This can help fix 'module not found' issues.
+// https://github.com/whitecolor/yalc
+
+export default class OHIFVTKExtension {
+  constructor(children) {
+    this.children = children;
+  }
+
+  /**
+   * Extension ID is a unique id, might be used for namespacing extension specific redux actions/reducers (?)
+   */
+  getExtensionId() {
+    return 'vtk';
+  }
+
+  getViewportModule() {
+    if (this.children && this.children.viewport) {
+      return withChildren(OHIFVTKViewport, this.children.viewport);
+    }
+
+    return OHIFVTKViewport;
+  }
+
+  getSopClassHandler() {
+    return null;
+  }
+
+  getPanelModule() {
+    return null;
+  }
+
+  getToolbarModule() {
+    return ToolbarModule;
+  }
+}