title: Keycloak - Didn't find publicKey for specified kid
body: <p>I have an application divided into frontend and backend services. The frontend has public acces, while the backend is confidential. When I'm trying to authorize to get response from my backend I'm getting the following error:</p>
  
  <pre><code>cache-control: no-cache, no-store, max-age=0, must-revalidate 
  content-length: 0 
  date: Fri, 06 Dec 2019 09:16:16 GMT 
  expires: 0 
  pragma: no-cache 
  vary: Origin, Access-Control-Request-Method, Access-Control-Request-Headers 
  www-authenticate: Bearer realm="my_realm", error="invalid_token", error_description="Didn't 
  find publicKey for specified kid", Bearer realm="my_realm", error="invalid_token", 
  error_description="Didn't find publicKey for specified kid" 
  x-content-type-options: nosniff 
  x-frame-options: DENY 
  x-xss-protection: 1; mode=block 
  </code></pre>
  
  <p>Here's my configuration for both services:</p>
  
  <pre><code>Backend:
      keycloak:
          auth-server-url: http://localhost:8081/auth
          realm: my_realm
          resource: your-client-id
          ssl-required: external
          credentials.secret: your-client-secret
  Frontend:
      sso: {
          url: 'http://localhost:8081/auth',
          realm: 'my_realm',
          clientId: 'your-frontend-client'
      }
  </code></pre>
  
  <p>I'm using keycloak 7.0.1 along with Spring Security. </p>
  
  <p>Am I missing any additional config for allowing authorization from public client?</p>