setup options handling in util

src/Handpose/index.js

@@ -12,6 +12,7 @@ import * as tf from "@tensorflow/tfjs";
 import * as handPoseDetection from "@tensorflow-models/hand-pose-detection";
 import callCallback from "../utils/callcallback";
 import handleArguments from "../utils/handleArguments";
+import handleOptions from "../utils/handleOptions";
 import { mediaReady } from "../utils/imageUtilities";
 
 class Handpose {
@@ -61,16 +62,33 @@ class Handpose {
   async loadModel() {
     const pipeline = handPoseDetection.SupportedModels.MediaPipeHands;
     //filter out model config options
-    const modelConfig = {
-      maxHands: this.config?.maxHands ?? 2,
-      runtime: this.config?.runtime ?? "mediapipe",
-      modelType: this.config?.modelType ?? "full",
-      solutionPath:
-        this.config?.solutionPath ??
-        "https://cdn.jsdelivr.net/npm/@mediapipe/hands",
-      detectorModelUrl: this.config?.detectorModelUrl,
-      landmarkModelUrl: this.config?.landmarkModelUrl,
-    };
+    const modelConfig = handleOptions(this.config, {
+      maxHands: {
+        type: "number",
+        default: 2,
+      },
+      runtime: {
+        type: "string",
+        default: "mediapipe",
+      },
+      modelType: {
+        type: "string",
+        default: "full",
+      },
+      solutionPath: {
+        type: "string",
+        default: "https://cdn.jsdelivr.net/npm/@mediapipe/hands",
+      },
+      detectorModelUrl: {
+        type: "string",
+        default: undefined,
+      },
+      landmarkModelUrl: {
+        type: "string",
+        default: undefined,
+      },
+    });
+    console.log(modelConfig);
     this.runtimeConfig = {
       flipHorizontal: this.config?.flipHorizontal ?? false,
     };

src/utils/handleOptions.js

@@ -0,0 +1,44 @@
+/**
+ * This function takes in an object of options and an object of molds.
+ * Filters the options based on the moldObject and returns the filtered options.
+ * Logs out friendly warnings if the user options are not of the correct type or value.
+ *
+ * @param {object} optionsObject - options provided by the user
+ * @param {object} moldObject - an object defining how the user option should be filtered
+ * @returns {object} - filtered options
+ */
+function handleOptions(optionsObject, moldObject) {
+  const options = {};
+
+  for (const key in moldObject) {
+    const userValue = optionsObject[key];
+    const type = moldObject[key].type;
+    const defaultValue = moldObject[key].default;
+
+    if (userValue === undefined) {
+      options[key] = defaultValue;
+    } else if (typeof userValue !== type) {
+      console.warn(
+        `The value of ${key} is not of type ${type}. Using default value ${defaultValue} instead.`
+      );
+      options[key] = defaultValue;
+    } else {
+      switch (type) {
+        case "string":
+          break;
+        case "number":
+          break;
+        case "boolean":
+          break;
+        case "object":
+          break;
+        default:
+          throw new Error(`Unknown type ${type} for ${key} in moldObject.`);
+      }
+    }
+  }
+
+  return options;
+}
+
+export default handleOptions;