fix(examples): remove incorrect POST binding query string example

SAMLResponse= in a query string implies HTTP-Redirect binding (DEFLATE
compressed). A POST binding SAMLResponse lives in the HTTP POST body — it
only looks like a query string when intercepted. Removed the misleadingly
labelled example and the encodePostBinding helper it depended on.

Author: kellenmurphy

src/lib/examples.test.ts

@@ -104,14 +104,6 @@ describe('EXAMPLES', () => {
         expect(decodeSaml(url!.payload()).summary.binding).toBe('redirect');
     });
 
-    it('POST binding example uses post binding', () => {
-        const post = EXAMPLES.find(
-            (e) => e.category === 'Query string' && e.label.includes('POST')
-        );
-        expect(post).toBeDefined();
-        expect(decodeSaml(post!.payload()).summary.binding).toBe('post');
-    });
-
     it('MFA SAMLResponse has REFEDS MFA authn context', () => {
         const mfa = EXAMPLES.find(
             (e) => e.category === 'SAMLResponse' && e.label.includes('MFA')

src/lib/examples.ts

@@ -37,15 +37,6 @@ function encodeRedirectBinding(xml: string): string {
     return encodeURIComponent(btoa(binary));
 }
 
-function encodePostBinding(xml: string): string {
-    const bytes = new TextEncoder().encode(xml);
-    let binary = '';
-    for (let i = 0; i < bytes.length; i++) {
-        binary += String.fromCharCode(bytes[i]);
-    }
-    return btoa(binary);
-}
-
 function b64url(obj: object): string {
     return btoa(JSON.stringify(obj))
         .replace(/=/g, '')
@@ -229,11 +220,6 @@ export const EXAMPLES: Example[] = [
         payload: () =>
             `SAMLRequest=${encodeRedirectBinding(samlRequest())}&RelayState=%2Fdashboard`,
     },
-    {
-        label: 'POST binding form value',
-        category: 'Query string',
-        payload: () => `SAMLResponse=${encodeURIComponent(encodePostBinding(samlResponse()))}`,
-    },
     {
         label: 'IdP redirect binding URL',
         category: 'Full URL',