form: update asking flow, separate form and options

src/tests/test_questions.py

@@ -11,11 +11,11 @@ from typing import Any, Literal, Sequence, TypedDict, Union
 
 from _pytest.mark.structures import ParameterSet
 
-
 from moulinette import Moulinette
 from yunohost import app, domain, user
 from yunohost.utils.form import (
     OPTIONS,
+    FORBIDDEN_PASSWORD_CHARS,
     ask_questions_and_parse_answers,
     BaseChoicesOption,
     BaseInputOption,
@@ -378,8 +378,8 @@ def _fill_or_prompt_one_option(raw_option, intake):
     options = {id_: raw_option}
     answers = {id_: intake} if intake is not None else {}
 
-    option = ask_questions_and_parse_answers(options, answers)[0]
+    options, form = ask_questions_and_parse_answers(options, answers)
-    return (option, option.value if isinstance(option, BaseInputOption) else None)
+    return (options[0], form[id_] if isinstance(options[0], BaseInputOption) else None)
 
 
 def _test_value_is_expected_output(value, expected_output):
@@ -551,7 +551,7 @@ class TestDisplayText(BaseTest):
                     ask_questions_and_parse_answers({_id: raw_option}, answers)
             else:
                 with patch.object(sys, "stdout", new_callable=StringIO) as stdout:
-                    options = ask_questions_and_parse_answers(
+                    options, form = ask_questions_and_parse_answers(
                         {_id: raw_option}, answers
                     )
                     assert stdout.getvalue() == f"{options[0].ask['en']}\n"
@@ -604,7 +604,7 @@ class TestAlert(TestDisplayText):
                     )
             else:
                 with patch.object(sys, "stdout", new_callable=StringIO) as stdout:
-                    options = ask_questions_and_parse_answers(
+                    options, form = ask_questions_and_parse_answers(
                         {"display_text_id": raw_option}, answers
                     )
                     ask = options[0].ask["en"]
@@ -1925,9 +1925,7 @@ def test_options_query_string():
             "&fake_id=fake_value"
         )
 
-    def _assert_correct_values(options, raw_options):
+    def _assert_correct_values(options, form, raw_options):
-        form = {option.id: option.value for option in options}
-
         for k, v in results.items():
             if k == "file_id":
                 assert os.path.exists(form["file_id"]) and os.path.isfile(
@@ -1943,24 +1941,24 @@ def test_options_query_string():
 
     with patch_interface("api"), patch_file_api(file_content1) as b64content:
         with patch_query_string(b64content.decode("utf-8")) as query_string:
-            options = ask_questions_and_parse_answers(raw_options, query_string)
+            options, form = ask_questions_and_parse_answers(raw_options, query_string)
-            _assert_correct_values(options, raw_options)
+            _assert_correct_values(options, form, raw_options)
 
     with patch_interface("cli"), patch_file_cli(file_content1) as filepath:
         with patch_query_string(filepath) as query_string:
-            options = ask_questions_and_parse_answers(raw_options, query_string)
+            options, form = ask_questions_and_parse_answers(raw_options, query_string)
-            _assert_correct_values(options, raw_options)
+            _assert_correct_values(options, form, raw_options)
 
 
 def test_question_string_default_type():
     questions = {"some_string": {}}
     answers = {"some_string": "some_value"}
 
-    out = ask_questions_and_parse_answers(questions, answers)[0]
+    options, form = ask_questions_and_parse_answers(questions, answers)
-
+    option = options[0]
-    assert out.id == "some_string"
+    assert option.id == "some_string"
-    assert out.type == "string"
+    assert option.type == "string"
-    assert out.value == "some_value"
+    assert form[option.id] == "some_value"
 
 
 def test_option_default_type_with_choices_is_select():

src/utils/form.py

@@ -25,17 +25,30 @@ import shutil
 import tempfile
 import urllib.parse
 from enum import Enum
-from typing import Any, Callable, Dict, List, Literal, Mapping, Union
 from logging import getLogger
+from typing import (
+    Annotated,
+    Any,
+    Callable,
+    List,
+    Literal,
+    Mapping,
+    Type,
+    Union,
+    cast,
+)
 
 from pydantic import (
     BaseModel,
+    Extra,
+    ValidationError,
+    create_model,
     root_validator,
     validator,
 )
 from pydantic.color import Color
+from pydantic.fields import Field
 from pydantic.networks import EmailStr, HttpUrl
-from pydantic.types import FilePath
 
 from moulinette import Moulinette, m18n
 from moulinette.interfaces.cli import colorize
@@ -385,15 +398,6 @@ class BaseInputOption(BaseOption):
             return None
         return value
 
-    # FIXME remove
-    def old__init__(self, question: Dict[str, Any]):
-        # .current_value is the currently stored value
-        self.current_value = question.get("current_value")
-        # .value is the "proposed" value which we got from the user
-        self.value = question.get("value")
-        # Use to return several values in case answer is in mutipart
-        self.values: Dict[str, Any] = {}
-
     @staticmethod
     def humanize(value, option={}):
         return str(value)
@@ -650,8 +654,6 @@ class DateOption(BaseInputOption):
     # }
 
     def _value_pre_validator(self):
-        from datetime import datetime
-
         super()._value_pre_validator()
 
         if self.value not in [None, ""]:
@@ -1069,6 +1071,120 @@ OPTIONS = {
     OptionType.group: GroupOption,
 }
 
+AnyOption = Union[
+    DisplayTextOption,
+    MarkdownOption,
+    AlertOption,
+    ButtonOption,
+    StringOption,
+    TextOption,
+    PasswordOption,
+    ColorOption,
+    NumberOption,
+    BooleanOption,
+    DateOption,
+    TimeOption,
+    EmailOption,
+    WebPathOption,
+    URLOption,
+    FileOption,
+    SelectOption,
+    TagsOption,
+    DomainOption,
+    AppOption,
+    UserOption,
+    GroupOption,
+]
+
+
+# ╭───────────────────────────────────────────────────────╮
+# │  ┌─╴╭─╮┌─╮╭╮╮                                         │
+# │  ├─╴│ │├┬╯│││                                         │
+# │  ╵  ╰─╯╵ ╰╵╵╵                                         │
+# ╰───────────────────────────────────────────────────────╯
+
+
+class OptionsModel(BaseModel):
+    # Pydantic will match option types to their models class based on the "type" attribute
+    options: list[Annotated[AnyOption, Field(discriminator="type")]]
+
+    @staticmethod
+    def options_dict_to_list(options: dict[str, Any], defaults: dict[str, Any] = {}):
+        return [
+            option
+            | {
+                "id": id_,
+                "type": option.get("type", "string"),
+            }
+            for id_, option in options.items()
+        ]
+
+    def __init__(self, **kwargs) -> None:
+        super().__init__(options=self.options_dict_to_list(kwargs))
+
+
+class FormModel(BaseModel):
+    """
+    Base form on which dynamic forms are built upon Options.
+    """
+
+    class Config:
+        validate_assignment = True
+        extra = Extra.ignore
+
+    def __getitem__(self, name: str):
+        # FIXME
+        # if a FormModel's required field is not instancied with a value, it is
+        # not available as an attr and therefor triggers an `AttributeError`
+        # Also since `BaseReadonlyOption`s do not end up in form,
+        # `form[AlertOption.id]` would also triggers an error
+        # For convinience in those 2 cases, we return `None`
+        if not hasattr(self, name):
+            # Return None to trigger a validation error instead for required fields
+            return None
+
+        return getattr(self, name)
+
+    def __setitem__(self, name: str, value: Any):
+        setattr(self, name, value)
+
+    def get(self, attr: str, default: Any = None) -> Any:
+        try:
+            return getattr(self, attr)
+        except AttributeError:
+            return default
+
+
+def build_form(options: list[AnyOption], name: str = "DynamicForm") -> Type[FormModel]:
+    """
+    Returns a dynamic pydantic model class that can be used as a form.
+    Parsing/validation occurs at instanciation and assignements.
+    To avoid validation at instanciation, use `my_form.construct(**values)`
+    """
+    options_as_fields: Any = {}
+    validators: dict[str, Any] = {}
+
+    for option in options:
+        if not isinstance(option, BaseInputOption):
+            continue  # filter out non input options
+
+        options_as_fields[option.id] = option._as_dynamic_model_field()
+
+        for step in ("pre", "post"):
+            validators[f"{option.id}_{step}_validator"] = validator(
+                option.id, allow_reuse=True, pre=step == "pre"
+            )(getattr(option, f"_value_{step}_validator"))
+
+    return cast(
+        Type[FormModel],
+        create_model(
+            name,
+            __base__=FormModel,
+            __validators__=validators,
+            **options_as_fields,
+        ),
+    )
+
 
 def hydrate_option_type(raw_option: dict[str, Any]) -> dict[str, Any]:
     type_ = raw_option.get(
@@ -1097,20 +1213,16 @@ Hooks = dict[str, Callable[[BaseInputOption], Any]]
 
 
 def prompt_or_validate_form(
-    raw_options: dict[str, Any],
+    options: list[AnyOption],
+    form: FormModel,
     prefilled_answers: dict[str, Any] = {},
     context: Context = {},
     hooks: Hooks = {},
-) -> list[BaseOption]:
+) -> FormModel:
-    options = []
     answers = {**prefilled_answers}
+    values = {}
 
-    for id_, raw_option in raw_options.items():
+    for option in options:
-        raw_option["id"] = id_
-        raw_option["value"] = answers.get(id_)
-        raw_option = hydrate_option_type(raw_option)
-        option = OPTIONS[raw_option["type"]](raw_option)
-
         interactive = Moulinette.interface.type == "cli" and os.isatty(1)
 
         if isinstance(option, ButtonOption):
@@ -1123,89 +1235,88 @@ def prompt_or_validate_form(
                     help=_value_for_locale(option.help),
                 )
 
-        # FIXME not sure why we do not append Buttons to returned options
-        options.append(option)
-
         if not option.is_visible(context):
             if isinstance(option, BaseInputOption):
                 # FIXME There could be several use case if the question is not displayed:
                 # - we doesn't want to give a specific value
                 # - we want to keep the previous value
                 # - we want the default value
-                option.value = context[option.id] = None
+                context[option.id] = form[option.id] = None
 
             continue
 
-        message = option._get_prompt_message()
+        # if we try to get a `BaseReadonlyOption` value, which doesn't exists in the form,
+        # we get `None`
+        value = form[option.id]
+
+        if isinstance(option, BaseReadonlyOption) or option.readonly:
+            if isinstance(option, BaseInputOption):
+                # FIXME normalized needed, form[option.id] should already be normalized
+                # only update the context with the value
+                context[option.id] = form[option.id]
+
+                # FIXME here we could error out
+                if option.id in prefilled_answers:
+                    logger.warning(
+                        f"'{option.id}' is readonly, value '{prefilled_answers[option.id]}' is then ignored."
+                    )
 
-        if option.readonly:
             if interactive:
-                Moulinette.display(message)
+                Moulinette.display(option._get_prompt_message(value))
-
-            if isinstance(option, BaseInputOption):
-                option.value = context[option.id] = option.current_value
 
             continue
 
-        if isinstance(option, BaseInputOption):
         for i in range(5):
-                if interactive and option.value is None:
+            if option.id in prefilled_answers:
-                    prefill = ""
+                value = prefilled_answers[option.id]
+            elif interactive:
+                value = option.humanize(value, option)
                 choices = (
                     option.choices if isinstance(option, BaseChoicesOption) else []
                 )
-
+                value = Moulinette.prompt(
-                    if option.current_value is not None:
+                    message=option._get_prompt_message(value),
-                        prefill = option.humanize(option.current_value, option)
-                    elif option.default is not None:
-                        prefill = option.humanize(option.default, option)
-
-                    option.value = Moulinette.prompt(
-                        message=message,
                     is_password=isinstance(option, PasswordOption),
                     confirm=False,
-                        prefill=prefill,
+                    prefill=value,
-                        is_multiline=(option.type == "text"),
+                    is_multiline=isinstance(option, TextOption),
                     autocomplete=choices,
                     help=_value_for_locale(option.help),
                 )
 
-                # Apply default value
+            # Apply default value if none
-                class_default = getattr(option, "default_value", None)
+            if value is None or value == "" and option.default is not None:
-                if option.value in [None, ""] and (
+                value = option.default
-                    option.default is not None or class_default is not None
-                ):
-                    option.value = (
-                        class_default if option.default is None else option.default
-                    )
 
             try:
                 # Normalize and validate
-                    option.value = option.normalize(option.value, option)
+                values[option.id] = form[option.id] = option.normalize(value, option)
-                    option._value_pre_validator()
+            except (ValidationError, YunohostValidationError) as e:
-                except YunohostValidationError as e:
                 # If in interactive cli, re-ask the current question
                 if i < 4 and interactive:
                     logger.error(str(e))
-                        option.value = None
+                    value = None
                     continue
 
+                if isinstance(e, ValidationError):
+                    error = "\n".join([err["msg"] for err in e.errors()])
+                    raise YunohostValidationError(error, raw_msg=True)
+
                 # Otherwise raise the ValidationError
-                    raise
+                raise e
 
             break
 
-            option.value = option.values[option.id] = option._value_post_validator()
-
         # Search for post actions in hooks
         post_hook = f"post_ask__{option.id}"
         if post_hook in hooks:
-                option.values.update(hooks[post_hook](option))
+            values.update(hooks[post_hook](option))
+            # FIXME reapply new values to form to validate it
 
-            answers.update(option.values)
+        answers.update(values)
-            context.update(option.values)
+        context.update(values)
 
-    return options
+    return form
 
 
 def ask_questions_and_parse_answers(
@@ -1213,7 +1324,7 @@ def ask_questions_and_parse_answers(
     prefilled_answers: Union[str, Mapping[str, Any]] = {},
     current_values: Mapping[str, Any] = {},
     hooks: Hooks = {},
-) -> list[BaseOption]:
+) -> tuple[list[AnyOption], FormModel]:
     """Parse arguments store in either manifest.json or actions.json or from a
     config panel against the user answers when they are present.
 
@@ -1241,9 +1352,21 @@ def ask_questions_and_parse_answers(
 
     context = {**current_values, **answers}
 
-    return prompt_or_validate_form(
+    # Validate/parse the options attributes
-        raw_options, prefilled_answers=answers, context=context, hooks=hooks
+    try:
+        model = OptionsModel(**raw_options)
+    except ValidationError as e:
+        error = "\n".join([err["msg"] for err in e.errors()])
+        # FIXME use YunohostError instead since it is not really a user mistake?
+        raise YunohostValidationError(error, raw_msg=True)
+
+    # Build the form from those questions and instantiate it without
+    # parsing/validation (construct) since it may contains required questions.
+    form = build_form(model.options).construct()
+    form = prompt_or_validate_form(
+        model.options, form, prefilled_answers=answers, context=context, hooks=hooks
     )
+    return (model.options, form)
 
 
 def hydrate_questions_with_choices(raw_questions: List) -> List:
@@ -1251,7 +1374,7 @@ def hydrate_questions_with_choices(raw_questions: List) -> List:
 
     for raw_question in raw_questions:
         raw_question = hydrate_option_type(raw_question)
-        question = OPTIONS[raw_question["type"]](raw_question)
+        question = OPTIONS[raw_question["type"]](**raw_question)
         if isinstance(question, BaseChoicesOption) and question.choices:
             raw_question["choices"] = question.choices
             raw_question["default"] = question.default