Merge pull request #163 from evert/has-link

Adding a 'hasLink' method, for easy checking if a certain link exists.

src/representor/base.ts

@@ -49,6 +49,15 @@ export default abstract class Representation<T = string> {
 
   }
 
+  /**
+   * Checks if the specified link exists on this representation.
+   */
+  hasLink(rel: string): boolean {
+
+    return this.links.has(rel) && this.links.get(rel)!.length > 0;
+
+  }
+
   getEmbedded(): { [uri: string]: T } {
 
     return {};

src/resource.ts

@@ -248,6 +248,16 @@ export default class Resource<TResource = any, TPatch = Partial<TResource>> {
 
   }
 
+  /**
+   * Checks if the current resource has the specified link relationship.
+   */
+  async hasLink(rel: string): Promise<boolean> {
+
+    const r = await this.representation();
+    return r.hasLink(rel);
+
+  }
+
   /**
    * Follows a relationship, based on its reltype. For example, this might be
    * 'alternate', 'item', 'edit' or a custom url-based one.