Set up the session for solid-auth-client w/ tls (#596)

Author: dan-f

default-views/auth/login-tls.hbs

@@ -8,3 +8,29 @@
     {{> auth/auth-hidden-fields}}
   </div>
 </form>
+
+<script type="text/javascript">
+  const button = document.getElementById('login-tls')
+  button.addEventListener('click', function(event) {
+    event.preventDefault()
+    fetch('/login/tls', { method: 'POST', credentials: 'include' })
+      .then(function(response) {
+        const webId = response.headers.get('user')
+        const idp = new URL(webId).origin
+        const session = { authType: 'WebID-TLS', webId, idp }
+        const authClientNamespace = 'solid-auth-client'
+        let authClientStore
+        try {
+          authClientStore = JSON.parse(localStorage.getItem(authClientNamespace) || '{}')
+        } catch (err) {
+          authClientStore = {}
+        }
+        authClientStore.session = session
+        localStorage.setItem(authClientNamespace, JSON.stringify(authClientStore))
+        return response
+      })
+      .then(function(response) {
+        window.location.href = response.url
+      })
+  })
+</script>