Add button to raise bogus error, for testing email alerts

tailbone/templates/settings/email/configure.mako

@@ -16,6 +16,57 @@
     </b-field>
 
   </div>
+
+  % if request.has_perm('errors.bogus'):
+      <h3 class="block is-size-3">Testing</h3>
+      <div class="block" style="padding-left: 2rem;">
+
+        <b-field grouped>
+          <p class="control">
+            You can raise a "bogus" error to test if/how it generates email:
+          </p>
+          <b-button type="is-primary"
+                    @click="raiseBogusError()"
+                    :disabled="raisingBogusError">
+            {{ raisingBogusError ? "Working, please wait..." : "Raise Bogus Error" }}
+          </b-button>
+        </b-field>
+
+      </div>
+      </h3>
+  % endif
+</%def>
+
+<%def name="modify_this_page_vars()">
+  ${parent.modify_this_page_vars()}
+  % if request.has_perm('errors.bogus'):
+      <script type="text/javascript">
+
+        ThisPageData.raisingBogusError = false
+
+        ThisPage.methods.raiseBogusError = function() {
+            this.raisingBogusError = true
+
+            let url = '${url('bogus_error')}'
+            this.$http.get(url).then(response => {
+                this.$buefy.toast.open({
+                    message: "Ironically, response was 200 which means we failed to raise an error!\n\nPlease investigate!",
+                    type: 'is-danger',
+                    duration: 5000, // 5 seconds
+                })
+                this.raisingBogusError = false
+            }, response => {
+                this.$buefy.toast.open({
+                    message: "Error was raised; please check your email and/or logs.",
+                    type: 'is-success',
+                    duration: 4000, // 4 seconds
+                })
+                this.raisingBogusError = false
+            })
+        }
+
+      </script>
+  % endif
 </%def>