Add supportsExtension to STAC entities

src/stac.js

@@ -282,6 +282,22 @@ class STAC extends STACHypermedia {
     return false;
   }
 
+  /**
+   * Checks whether a specific extension is implemented.
+   * 
+   * The pattern can contain `*` as a wildcard, e.g. for version numbers.
+   * 
+   * @param {*} pattern 
+   * @returns 
+   */
+  supportsExtension(pattern) {
+    if (!Array.isArray(this.stac_extensions)) {
+      return false;
+    }
+    let regexp = new RegExp('^' + pattern.replaceAll('*', '[^/]+') + '$');
+    return Boolean(this.stac_extensions.find(uri => regexp.test(uri)));
+  }
+
 }
 
 export default STAC;