Added Support for Limit M2M Auth API

src/index.ts

@@ -3,4 +3,5 @@ export * from './auth/index.js';
 export * from './userinfo/index.js';
 export * from './lib/errors.js';
 export * from './lib/models.js';
+export * from './lib/httpResponseHeadersUtils.js';
 export * from './deprecations.js';

src/lib/httpResponseHeadersUtils.ts

@@ -0,0 +1,97 @@
+export interface TokenQuotaLimit {
+  quota: number;
+  remaining: number;
+  time: number;
+}
+
+export interface TokenQuotaBucket {
+  perHour?: TokenQuotaLimit;
+  perDay?: TokenQuotaLimit;
+}
+
+export class HttpResponseHeadersUtils {
+  /**
+   * Gets the client token quota limits from the provided headers.
+   *
+   * @param headers the HTTP response headers.
+   * @return a TokenQuotaBucket containing client rate limits, or null if not present.
+   */
+  static getClientQuotaLimit(headers: Headers | Record<string, string>): TokenQuotaBucket | null {
+    const getHeaderValue = (key: string): string | null => {
+      if (headers instanceof Headers) {
+        return headers.get(key);
+      }
+      return headers[key] || null;
+    };
+
+    const quotaHeader =
+      getHeaderValue('x-quota-client-limit') || getHeaderValue('auth0-quota-client-limit');
+    return quotaHeader ? this.parseQuota(quotaHeader) : null;
+  }
+
+  /**
+   * Gets the organization token quota limits from the provided headers.
+   *
+   * @param headers the HTTP response headers.
+   * @return a TokenQuotaBucket containing organization rate limits, or null if not present.
+   */
+  static getOrganizationQuotaLimit(
+    headers: Headers | Record<string, string>
+  ): TokenQuotaBucket | null {
+    const getHeaderValue = (key: string): string | null => {
+      if (headers instanceof Headers) {
+        return headers.get(key);
+      }
+      return headers[key] || null;
+    };
+
+    const quotaHeader =
+      getHeaderValue('x-quota-Organization-limit') ||
+      getHeaderValue('auth0-quota-Organization-limit');
+    return quotaHeader ? this.parseQuota(quotaHeader) : null;
+  }
+
+  /**
+   * Parses a token quota string into a TokenQuotaBucket.
+   *
+   * @param tokenQuota the token quota string.
+   * @return a TokenQuotaBucket containing parsed rate limits.
+   */
+  private static parseQuota(tokenQuota: string): TokenQuotaBucket {
+    let perHour: TokenQuotaLimit | undefined;
+    let perDay: TokenQuotaLimit | undefined;
+
+    const parts = tokenQuota.split(',');
+    for (const part of parts) {
+      const attributes = part.split(';');
+      let quota = 0,
+        remaining = 0,
+        time = 0;
+
+      for (const attribute of attributes) {
+        const [key, value] = attribute.split('=').map((s) => s.trim());
+        if (!key || !value) continue;
+
+        switch (key) {
+          case 'q':
+            quota = parseInt(value, 10);
+            break;
+          case 'r':
+            remaining = parseInt(value, 10);
+            break;
+          case 't':
+            time = parseInt(value, 10);
+            break;
+        }
+      }
+
+      if (attributes[0].includes('per_hour')) {
+        perHour = { quota, remaining, time };
+      } else if (attributes[0].includes('per_day')) {
+        perDay = { quota, remaining, time };
+      }
+    }
+
+    return { perHour, perDay };
+  }
+}

test/lib/HttpResponseHeadersUtils.test.ts

@@ -0,0 +1,65 @@
+import { HttpResponseHeadersUtils } from '../../src/lib/httpResponseHeadersUtils.js';
+
+describe('HttpResponseHeadersUtils', () => {
+  describe('getClientQuotaLimit', () => {
+    it('should return a valid TokenQuotaBucket when x-quota-client-limit header is present', () => {
+      const headers = {
+        'x-quota-client-limit': 'per_hour;q=100;r=50;t=3600,per_day;q=1000;r=500;t=86400',
+      };
+      const result = HttpResponseHeadersUtils.getClientQuotaLimit(headers);
+      expect(result).toEqual({
+        perHour: { quota: 100, remaining: 50, time: 3600 },
+        perDay: { quota: 1000, remaining: 500, time: 86400 },
+      });
+    });
+
+    it('should return null when no relevant headers are present', () => {
+      const headers = { 'some-other-header': 'value' };
+      const result = HttpResponseHeadersUtils.getClientQuotaLimit(headers);
+      expect(result).toBeNull();
+    });
+  });
+
+  describe('getOrganizationQuotaLimit', () => {
+    it('should return a valid TokenQuotaBucket when x-quota-Organization-limit header is present', () => {
+      const headers = { 'x-quota-Organization-limit': 'per_hour;q=200;r=150;t=3600' };
+      const result = HttpResponseHeadersUtils.getOrganizationQuotaLimit(headers);
+      expect(result).toEqual({
+        perHour: { quota: 200, remaining: 150, time: 3600 },
+        perDay: undefined,
+      });
+    });
+
+    it('should return null when no relevant headers are present', () => {
+      const headers = { 'some-other-header': 'value' };
+      const result = HttpResponseHeadersUtils.getOrganizationQuotaLimit(headers);
+      expect(result).toBeNull();
+    });
+  });
+
+  describe('parseQuota', () => {
+    it('should correctly parse a token quota string into a TokenQuotaBucket', () => {
+      const tokenQuota = 'per_hour;q=300;r=250;t=3600,per_day;q=3000;r=2500;t=86400';
+      const result = HttpResponseHeadersUtils['parseQuota'](tokenQuota);
+      expect(result).toEqual({
+        perHour: { quota: 300, remaining: 250, time: 3600 },
+        perDay: { quota: 3000, remaining: 2500, time: 86400 },
+      });
+    });
+
+    it('should handle missing attributes gracefully', () => {
+      const tokenQuota = 'per_hour;q=300;r=250';
+      const result = HttpResponseHeadersUtils['parseQuota'](tokenQuota);
+      expect(result).toEqual({
+        perHour: { quota: 300, remaining: 250, time: 0 },
+        perDay: undefined,
+      });
+    });
+
+    it('should return an empty TokenQuotaBucket for invalid input', () => {
+      const tokenQuota = 'invalid_format';
+      const result = HttpResponseHeadersUtils['parseQuota'](tokenQuota);
+      expect(result).toEqual({ perHour: undefined, perDay: undefined });
+    });
+  });
+});