Javascript credential issuing service

_code-samples/issue-credentials/js/look_up_credentials.js

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+import { ValueError } from "./errors.js";
+
+const lsfAccepted = 0x00010000;
+
+/**
+ * Looks up Credentials issued by/to a specified XRPL account, optionally
+ * filtering by accepted status. Handles pagination.
+ */
+export async function lookUpCredentials(client, issuer, subject, accepted = "both") {
+  const account = issuer || subject;
+  if (!account) {
+    throw new ValueError("Must specify issuer or subject");
+  }
+
+  accepted = accepted.toLowerCase();
+  if (!["yes", "no", "both"].includes(accepted)) {
+    throw new ValueError("accepted must be 'yes', 'no', or 'both'");
+  }
+
+  const credentials = [];
+  let request = {
+    command: "account_objects",
+    account,
+    type: "credential",
+  };
+
+  // Fetch first page
+  let response = await client.request(request);
+
+  while (true) {
+    for (const obj of response.result.account_objects) {
+      if (issuer && obj.Issuer !== issuer) continue;
+      if (subject && obj.Subject !== subject) continue;
+
+      const credAccepted = Boolean(obj.Flags & lsfAccepted);
+      if (accepted === "yes" && !credAccepted) continue;
+      if (accepted === "no" && credAccepted) continue;
+
+      credentials.push(obj);
+    }
+
+    if (!response.result.marker) break;
+
+    /** 
+     * If there is marker, request the next page using the convenience function "requestNextPage()".
+     * See https://js.xrpl.org/classes/Client.html#requestnextpage to learn more.
+     **/ 
+    response = await client.requestNextPage(request, response.result);
+  }
+
+  return credentials;
+}