From 0670b0b5cb28a6322364f791560ce8d6a72c27ff Mon Sep 17 00:00:00 2001
From: Maximilian Haye <m.haye@tu-berlin.de>
Date: Mon, 16 Dec 2024 13:04:36 +0100
Subject: [PATCH] feat: add GeneratedIdElement

See: questionpy-org/questionpy-sdk#140
---
 docs/qppe-server.yaml         | 12 ++++++++++++
 questionpy_common/elements.py | 11 +++++++++++
 2 files changed, 23 insertions(+)

diff --git a/docs/qppe-server.yaml b/docs/qppe-server.yaml
index d4bebfa..283fb64 100644
--- a/docs/qppe-server.yaml
+++ b/docs/qppe-server.yaml
@@ -1429,6 +1429,17 @@ components:
           minItems: 1
       required: [ kind, name, initial_elements, increment, elements ]
 
+    GeneratedIdElement:
+      type: object
+      description: Generates a unique ID which won't change across form saves.
+      properties:
+        kind:
+          type: string
+          enum: [ id ]
+        name:
+          $ref: "#/components/schemas/FormName"
+      required: [ kind, name ]
+
     FormElement:
       oneOf:
         - $ref: "#/components/schemas/StaticTextElement"
@@ -1440,6 +1451,7 @@ components:
         - $ref: "#/components/schemas/HiddenElement"
         - $ref: "#/components/schemas/GroupElement"
         - $ref: "#/components/schemas/RepetitionElement"
+        - $ref: "#/components/schemas/GeneratedIdElement"
 
     FormSection:
       type: object
diff --git a/questionpy_common/elements.py b/questionpy_common/elements.py
index c0b5a1e..491cf0a 100644
--- a/questionpy_common/elements.py
+++ b/questionpy_common/elements.py
@@ -14,6 +14,7 @@
     "CheckboxGroupElement",
     "FormElement",
     "FormSection",
+    "GeneratedIdElement",
     "GroupElement",
     "HiddenElement",
     "Option",
@@ -167,6 +168,15 @@ class RepetitionElement(_BaseElement):
     """Elements that will be repeated."""
 
 
+class GeneratedIdElement(_BaseElement):
+    """Generates a unique ID which won't change across form saves.
+
+    Useful to distinguish repetitions without relying on their index, which may change when repetitions are removed.
+    """
+
+    kind: Literal["id"] = "id"
+
+
 FormElement: TypeAlias = Annotated[
     CheckboxElement
     | CheckboxGroupElement
@@ -174,6 +184,7 @@ class RepetitionElement(_BaseElement):
     | HiddenElement
     | RadioGroupElement
     | RepetitionElement
+    | GeneratedIdElement
     | SelectElement
     | StaticTextElement
     | TextInputElement