Feature: Extensions - Making more than one Blueprint possible (crypto…

…advance#1764)

* Making more than one Blueprint possible

* making many blueprints backwards compatible with one, reactivating all extension in the config

* bugfixes for hasty commit should fix testspyte

* fix tests and backwards-comp

* docs

* bugfix

* default blueprint anhd better error feedback

* documentation

docs/services/services.md

@@ -41,6 +41,45 @@ If the extension has a UI (currently all of them have one), `has_blueprint` is T
 `isolated_client` Should not be used yet. It is determining where in the url-path-tree the blueprint will be mounted. This might have an impact on whether the extension's frontend-client has access to the cookie used in specter. Check `config.py` for details.
 `devstatus` is one of `devstatus_alpha`, `devstatus_beta` or `devstatus_prod` defined in `cryptoadvance.specter.services.service`. Each specter-instance will have a config-variable  called `SERVICES_DEVSTATUS_THRESHOLD` (prod in Production and alpha in Development) and depending on that, the plugin will be available to the user.
 
+## Frontend aspects
+
+As stated, you can have your own frontend with a blueprint. If you only have one, it needs to have a `/` route in order to be linkable from the `choose your plugin` page. 
+If you create your extension with a blueprint, it'll create also a controller for you which, simplified, look like this:
+```
+rubberduck_endpoint = ScratchpadService.blueprint
+
+def ext() -> ScratchpadService:
+    ''' convenience for getting the extension-object'''
+    return app.specter.ext["rubberduck"]
+
+def specter() -> Specter:
+    ''' convenience for getting the specter-object'''
+    return app.specter
+
+
+@rubberduck.route("/")
+@login_required
+@user_secret_decrypted_required
+def index():
+    return render_template(
+        "rubberduck/index.jinja",
+    )
+[...]
+```
+ But you can also have more than one blueprint. Define them like this in your service-class:
+```
+    blueprint_modules = { 
+        "default" : "mynym.specterext.rubberduck.controller",
+        "ui" : "mynym.specterext.rubberduck.controller_ui"
+    }
+```
+You have to have a default-blueprint which has the above mentioned index-page.
+In your controller, the endpoint needs to be specified like this:
+```
+ui = RubberduckService.blueprints["ui"]
+```
+
+
 ## Data-Storage
 Effort has been taken to provide `Service` data storage that is separate from existing data stores in order to keep those areas clean and simple. Where touchpoints are unavoidable, they are kept to the absolute bare minimum (e.g. `User.services` list, `Address.service_id` field).
 

src/cryptoadvance/specter/managers/service_manager.py

@@ -102,69 +102,104 @@ def __init__(self, specter, devstatus_threshold):
     def register_blueprint_for_ext(cls, clazz, ext):
         if not clazz.has_blueprint:
             return
-        if hasattr(clazz, "blueprint_module"):
-            import_name = clazz.blueprint_module
-            controller_module = clazz.blueprint_module
+        if hasattr(clazz, "blueprint_modules"):
+            controller_modules = clazz.blueprint_modules
+            setattr(clazz, "blueprints", {})
+        elif hasattr(clazz, "blueprint_module"):
+            controller_modules = {"default": clazz.blueprint_module}
         else:
-            # The import_name helps to locate the root_path for the blueprint
             import_name = f"cryptoadvance.specter.services.{clazz.id}.service"
-            controller_module = f"cryptoadvance.specter.services.{clazz.id}.controller"
+            controller_modules = controller_modules = {
+                "default": f"cryptoadvance.specter.services.{clazz.id}.controller"
+            }
 
-        clazz.blueprint = Blueprint(
-            f"{clazz.id}_endpoint",
-            import_name,
-            template_folder=get_template_static_folder("templates"),
-            static_folder=get_template_static_folder("static"),
-        )
+        only_one_blueprint = len(controller_modules.items()) == 1
 
         def inject_stuff():
             """Can be used in all jinja2 templates"""
             return dict(specter=app.specter, service=ext)
 
-        clazz.blueprint.context_processor(inject_stuff)
+        if "default" not in controller_modules.keys():
+            raise SpecterError(
+                "You need at least one Blueprint, with the key 'default'. It will be used to link to your UI"
+            )
 
-        # Import the controller for this service
-        logger.info(f"  Loading Controller {controller_module}")
-        controller_module = import_module(controller_module)
+        for bp_key, bp_value in controller_modules.items():
+            if bp_key == "":
+                raise SpecterError("Empty keys are not allowed in the blueprints map")
+            middple_part = "" if bp_key == "default" else f"{bp_key}_"
+            bp_name = f"{clazz.id}_{middple_part}endpoint"
+            logger.debug(
+                f"  Creating blueprint with name {bp_name} (middle_part:{middple_part}:"
+            )
+            bp = Blueprint(
+                f"{clazz.id}_{middple_part}endpoint",
+                bp_value,
+                template_folder=get_template_static_folder("templates"),
+                static_folder=get_template_static_folder("static"),
+            )
+            if only_one_blueprint:
+                setattr(clazz, "blueprint", bp)
+            else:
+                clazz.blueprints[bp_key] = bp
+            bp.context_processor(inject_stuff)
 
-        # finally register the blueprint
-        if clazz.isolated_client:
-            ext_prefix = app.config["ISOLATED_CLIENT_EXT_URL_PREFIX"]
-        else:
-            ext_prefix = app.config["EXT_URL_PREFIX"]
+            # Import the controller for this service
+            logger.info(f"  Loading Controller {bp_value}")
 
-        try:
-            if (
-                app.testing
-                and len([vf for vf in app.view_functions if vf.startswith(clazz.id)])
-                <= 1
-            ):  # the swan-static one
-                # Yet again that nasty workaround which has been described in the archblog.
-                # The easy variant can be found in server.py
-                # The good news is, that we'll only do that for testing
-                import importlib
-
-                logger.info("Reloading Extension controller")
-                importlib.reload(controller_module)
-                app.register_blueprint(
-                    clazz.blueprint, url_prefix=f"{ext_prefix}/{clazz.id}"
-                )
-            else:
-                app.register_blueprint(
-                    clazz.blueprint, url_prefix=f"{ext_prefix}/{clazz.id}"
-                )
-            logger.info(f"  Mounted {clazz.id} to {ext_prefix}/{clazz.id}")
-        except AssertionError as e:
-            if str(e).startswith("A name collision"):
-                raise SpecterError(
+            try:
+                controller_module = import_module(bp_value)
+            except ModuleNotFoundError as e:
+                raise Exception(
                     f"""
-                There is a name collision for the {clazz.blueprint.name}. \n
-                This is probably because you're running in DevelopementConfig and configured
-                the extension at the same time in the EXTENSION_LIST which currently loks like this:
-                {app.config['EXTENSION_LIST']})
+                    There was an issue finding a controller module:
+                    {e}
+                    That module was specified in the Service class of service {clazz.id}
+                    check that specification in {clazz.__module__}
                 """
                 )
 
+            # finally register the blueprint
+            if clazz.isolated_client:
+                ext_prefix = app.config["ISOLATED_CLIENT_EXT_URL_PREFIX"]
+            else:
+                ext_prefix = app.config["EXT_URL_PREFIX"]
+
+            try:
+                bp_postfix = "" if only_one_blueprint else f"/{bp_key}"
+                if (
+                    app.testing
+                    and len(
+                        [vf for vf in app.view_functions if vf.startswith(clazz.id)]
+                    )
+                    <= 1
+                ):  # the swan-static one
+                    # Yet again that nasty workaround which has been described in the archblog.
+                    # The easy variant can be found in server.py
+                    # The good news is, that we'll only do that for testing
+                    import importlib
+
+                    logger.info("Reloading Extension controller")
+                    importlib.reload(controller_module)
+                    app.register_blueprint(
+                        bp, url_prefix=f"{ext_prefix}/{clazz.id}{bp_postfix}"
+                    )
+                else:
+                    app.register_blueprint(
+                        bp, url_prefix=f"{ext_prefix}/{clazz.id}{bp_postfix}"
+                    )
+                logger.info(f"  Mounted {bp} to {ext_prefix}/{clazz.id}{bp_postfix}")
+            except AssertionError as e:
+                if str(e).startswith("A name collision"):
+                    raise SpecterError(
+                        f"""
+                    There is a name collision for the {clazz.blueprint.name}. \n
+                    This is probably because you're running in DevelopementConfig and configured
+                    the extension at the same time in the EXTENSION_LIST which currently loks like this:
+                    {app.config['EXTENSION_LIST']})
+                    """
+                    )
+
     @classmethod
     def configure_service_for_module(cls, clazz):
         """searches for ConfigClasses in the module-Directory and merges its config in the global config"""

src/cryptoadvance/specter/util/reflection.py

@@ -200,6 +200,10 @@ def get_subclasses_for_clazz(clazz, package_dirs: List[str] = None):
                         * {orgname}.specterext.{module_name}.service
                         Maybe you did forget to do this:
                         $ pip3 install -e .
+
+                        OR The Module has been found, but had issues finding Modules itself
+
+                        {e}
                         """
                             )
                         else: