Add iterator node (baserow#4099)

* Refactor the graph
* Many other stuff

Author: jrmi

backend/src/baserow/contrib/automation/api/nodes/errors.py

@@ -1,7 +1,13 @@
 from rest_framework.status import HTTP_400_BAD_REQUEST, HTTP_404_NOT_FOUND
 
-ERROR_AUTOMATION_NODE_BEFORE_INVALID = (
-    "ERROR_AUTOMATION_NODE_BEFORE_INVALID",
+ERROR_AUTOMATION_UNEXPECTED_ERROR = (
+    "ERROR_AUTOMATION_UNEXPECTED_ERROR",
+    HTTP_400_BAD_REQUEST,
+    "{e}",
+)
+
+ERROR_AUTOMATION_NODE_REFERENCE_NODE_INVALID = (
+    "ERROR_AUTOMATION_NODE_REFERENCE_NODE_INVALID",
     HTTP_400_BAD_REQUEST,
     "{e}",
 )
@@ -24,11 +30,25 @@
     "{e}",
 )
 
-ERROR_AUTOMATION_TRIGGER_NODE_MODIFICATION_DISALLOWED = (
-    "ERROR_AUTOMATION_TRIGGER_NODE_MODIFICATION_DISALLOWED",
+
+ERROR_AUTOMATION_TRIGGER_MUST_BE_FIRST_NODE = (
+    "ERROR_AUTOMATION_TRIGGER_MUST_BE_FIRST_NODE",
+    HTTP_400_BAD_REQUEST,
+    "This operation is disallowed because a trigger must be the first node of "
+    "the workflow",
+)
+
+ERROR_AUTOMATION_FIRST_NODE_MUST_BE_TRIGGER = (
+    "ERROR_AUTOMATION_FIRST_NODE_MUST_BE_TRIGGER",
+    HTTP_400_BAD_REQUEST,
+    "This operation is disallowed because an action can't be the first node of "
+    "the workflow",
+)
+
+ERROR_AUTOMATION_TRIGGER_ALREADY_EXISTS = (
+    "ERROR_AUTOMATION_TRIGGER_ALREADY_EXISTS",
     HTTP_400_BAD_REQUEST,
-    "Triggers can not be created, deleted or duplicated, "
-    "they can only be replaced with a different type.",
+    "This workflow already has a trigger",
 )
 
 ERROR_AUTOMATION_NODE_NOT_DELETABLE = (

backend/src/baserow/contrib/automation/api/nodes/serializers.py

@@ -10,6 +10,7 @@
 )
 from baserow.contrib.automation.nodes.models import AutomationNode
 from baserow.contrib.automation.nodes.registries import automation_node_type_registry
+from baserow.contrib.automation.nodes.types import NodePosition
 
 
 class AutomationNodeSerializer(serializers.ModelSerializer):
@@ -19,42 +20,25 @@ class AutomationNodeSerializer(serializers.ModelSerializer):
     service = PolymorphicServiceSerializer(
         help_text="The service associated with this automation node."
     )
-    simulate_until_node = serializers.SerializerMethodField(
-        help_text="Whether to simulate the dispatching of the node."
-    )
 
     @extend_schema_field(OpenApiTypes.STR)
     def get_type(self, instance):
         return automation_node_type_registry.get_by_model(instance.specific_class).type
 
-    @extend_schema_field(OpenApiTypes.BOOL)
-    def get_simulate_until_node(self, instance):
-        if not instance.workflow.simulate_until_node:
-            return False
-
-        return instance == instance.workflow.simulate_until_node.specific
-
     class Meta:
         model = AutomationNode
         fields = (
             "id",
             "label",
-            "order",
             "service",
             "workflow",
             "type",
-            "previous_node_id",
-            "previous_node_output",
-            "simulate_until_node",
         )
 
         extra_kwargs = {
             "id": {"read_only": True},
             "workflow_id": {"read_only": True},
             "type": {"read_only": True},
-            "previous_node_id": {"read_only": True},
-            "order": {"read_only": True, "help_text": "Lowest first."},
-            "simulate_until_node": {"read_only": True},
         }
 
 
@@ -64,23 +48,33 @@ class CreateAutomationNodeSerializer(serializers.ModelSerializer):
         required=True,
         help_text="The type of the automation node",
     )
-    before_id = serializers.IntegerField(
+    reference_node_id = serializers.IntegerField(
         required=False,
-        help_text="If provided, creates the node before the node with the given id.",
+        allow_null=True,
+        help_text="If provided, creates the node relative to the node with the "
+        "given id.",
     )
-    previous_node_id = serializers.IntegerField(
+    position = serializers.ChoiceField(
+        choices=NodePosition.choices,
         required=False,
-        help_text="If provided, creates the node after this given id.",
+        allow_blank=True,
+        help_text="The position of the new node relative to the reference node.",
     )
-    previous_node_output = serializers.CharField(
+    output = serializers.CharField(
         required=False,
         allow_blank=True,
         help_text="The unique ID of the branch this node is an output for.",
     )
 
     class Meta:
         model = AutomationNode
-        fields = ("id", "type", "before_id", "previous_node_id", "previous_node_output")
+        fields = (
+            "id",
+            "type",
+            "reference_node_id",
+            "position",
+            "output",
+        )
 
 
 class UpdateAutomationNodeSerializer(serializers.ModelSerializer):
@@ -93,17 +87,9 @@ class Meta:
         fields = (
             "label",
             "service",
-            "previous_node_output",
         )
 
 
-class OrderAutomationNodesSerializer(serializers.Serializer):
-    node_ids = serializers.ListField(
-        child=serializers.IntegerField(),
-        help_text=("The ids of the nodes in the order they are supposed to be set in."),
-    )
-
-
 class ReplaceAutomationNodeSerializer(serializers.Serializer):
     new_type = serializers.ChoiceField(
         choices=lazy(automation_node_type_registry.get_types, list)(),
@@ -113,12 +99,18 @@ class ReplaceAutomationNodeSerializer(serializers.Serializer):
 
 
 class MoveAutomationNodeSerializer(serializers.Serializer):
-    previous_node_id = serializers.IntegerField(
+    reference_node_id = serializers.IntegerField(
         required=False,
-        help_text="The ID of the node that should be before the moved node.",
+        help_text="The reference node.",
+    )
+    position = serializers.ChoiceField(
+        choices=NodePosition.choices,
+        required=False,
+        allow_blank=True,
+        help_text="The new position relative to the reference node.",
     )
-    previous_node_output = serializers.CharField(
+    output = serializers.CharField(
         required=False,
         allow_blank=True,
-        help_text="The output UID of the destination.",
+        help_text="The new output.",
     )

backend/src/baserow/contrib/automation/api/nodes/urls.py

@@ -5,7 +5,6 @@
     AutomationNodeView,
     DuplicateAutomationNodeView,
     MoveAutomationNodeView,
-    OrderAutomationNodesView,
     ReplaceAutomationNodeView,
     SimulateDispatchAutomationNodeView,
 )
@@ -23,11 +22,6 @@
         AutomationNodeView.as_view(),
         name="item",
     ),
-    re_path(
-        r"workflow/(?P<workflow_id>[0-9]+)/order/$",
-        OrderAutomationNodesView.as_view(),
-        name="order",
-    ),
     re_path(
         r"node/(?P<node_id>[0-9]+)/duplicate/$",
         DuplicateAutomationNodeView.as_view(),