add automatic registration of new deployment_ids

src/LtiTool.php

@@ -42,4 +42,44 @@ protected function onError() : void
     {
         throw new LtiException($this->reason);
     }
+
+    /**
+     * In the LTI 1.3 launch process, the LMS provides a `deployment_id`, specifying the
+     * placement of a tool.  This deployment_id must be explicitly registered by hand as
+     * part of the installation process.  The presence of a deployment_id is treated as
+     * mandatory by the underlying CeLTIc library.  But for freely-available tools, the
+     * deployment_id isn't really used - you don't really care to distinguish between
+     * individual deployments of the tool (the way you would for billing purposes in
+     * a commercial tool, say).
+     *
+     * This function allows tools to bypass CeLTIc's mandatory deployment_id checks, by
+     * assuming that the tool has been successfully deployed once, and copying that
+     * deployment with the new deployment_id provided in the request.  Functionally, this
+     * is likely he same thing you'd be asking your users to do by hand.
+     */
+    public function createDeploymentIdFromExistingPlatform() : void
+    {
+        if (request('iss')!==null && request('client_id')!==null && request('lti_deployment_id')!==null) {
+            $platform_id = request('iss');
+            $client_id = request('client_id');
+            $deployment_id = request('lti_deployment_id');
+            $platform = DB::table('lti2_consumer')
+                ->where('platform_id', $platform_id)
+                ->where('client_id', $client_id)
+                ->where('deployment_id', $deployment_id)
+                ->get();
+            if (count($platform) === 0) {
+                $platform = DB::table('lti2_consumer')
+                    ->where('platform_id', $platform_id)
+                    ->where('client_id', $client_id)
+                    ->get();
+                if (count($platform) > 0) {
+                    $new_platform = (array)$platform[0];
+                    unset($new_platform['consumer_pk']);
+                    $new_platform['deployment_id'] = $deployment_id;
+                    DB::table('lti2_consumer')->insert($new_platform);
+                }
+            }
+        }
+    }
 }