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  1. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 6 additions and 6 deletions.
    12 changes: 6 additions & 6 deletions autodetector.md
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    @@ -6,7 +6,7 @@

    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. Using the flag `--no-input` isn't enough as there is still 3 scenarios that raise the questioner.

    #### Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`.
    **Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`.**

    When we send the flag `--no-input` to the `makemigrations` command it calls the non-interactive questioner.

    @@ -18,7 +18,7 @@ else:
    questioner = NonInteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
    ```

    #### `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in three methods.
    **`NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in three methods.**

    [Source code](https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L227-L239):
    ```python
    @@ -37,9 +37,9 @@ class NonInteractiveMigrationQuestioner(MigrationQuestioner):
    sys.exit(3)
    ```

    With thit in mind, if we want to prevent a exit code other than 0 (successful exit) we have to avoid the call of the 3 following methods.
    With this in mind, if we want to prevent a exit code other than 0 (successful exit) we have to avoid the call of the 3 methods.

    #### `ask_auto_now_add_addition` and `ask_not_null_addition`
    -**`ask_auto_now_add_addition` and `ask_not_null_addition`**

    This is from [where](https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py#L860-L871) they can be called:
    ```python
    @@ -57,7 +57,7 @@ if not preserve_default:
    field.default = self.questioner.ask_not_null_addition(field_name, model_name)
    ```

    #### `ask_not_null_alteration`
    **`ask_not_null_alteration`**

    This is from [where](https://github.com/django/django/blob/5931d2e96ae94b204d146b7f751e0e804da74953/django/db/migrations/autodetector.py#L959-L962) it can be called:
    ```python
    @@ -96,7 +96,7 @@ def ask_not_null_alteration(self, field_name, model_name):
    return None
    ```

    #### TL;DR
    **TL;DR**

    The magic sauce:

  2. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 2 additions and 2 deletions.
    4 changes: 2 additions & 2 deletions autodetector.md
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    #### Introduction

    *Issue*: sys.exit(3) on background job that runs makemigrations - infinite loop
    **Issue**: sys.exit(3) on background job that runs makemigrations - infinite loop

    *PR*: https://github.com/crowdbotics/crowdbotics-slack-app/pull/1003
    **PR**: https://github.com/crowdbotics/crowdbotics-slack-app/pull/1003

    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. Using the flag `--no-input` isn't enough as there is still 3 scenarios that raise the questioner.

  3. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 3 additions and 2 deletions.
    5 changes: 3 additions & 2 deletions autodetector.md
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    @@ -1,7 +1,8 @@
    #### Introduction

    Issue: sys.exit(3) on background job that runs makemigrations - infinite loop
    PR: https://github.com/crowdbotics/crowdbotics-slack-app/pull/1003
    *Issue*: sys.exit(3) on background job that runs makemigrations - infinite loop

    *PR*: https://github.com/crowdbotics/crowdbotics-slack-app/pull/1003

    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. Using the flag `--no-input` isn't enough as there is still 3 scenarios that raise the questioner.

  4. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 3 additions and 0 deletions.
    3 changes: 3 additions & 0 deletions autodetector.md
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    Original file line number Diff line number Diff line change
    @@ -1,5 +1,8 @@
    #### Introduction

    Issue: sys.exit(3) on background job that runs makemigrations - infinite loop
    PR: https://github.com/crowdbotics/crowdbotics-slack-app/pull/1003

    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. Using the flag `--no-input` isn't enough as there is still 3 scenarios that raise the questioner.

    #### Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`.
  5. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion autodetector.md
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    @@ -1,6 +1,6 @@
    #### Introduction

    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. If we use the flag `--no-input` it isn't enough as 2 scenarios still raise the questioner no matter what.
    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. Using the flag `--no-input` isn't enough as there is still 3 scenarios that raise the questioner.

    #### Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`.

  6. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion autodetector.md
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    ## Introduction
    #### Introduction

    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. If we use the flag `--no-input` it isn't enough as 2 scenarios still raise the questioner no matter what.

  7. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 2 additions and 2 deletions.
    4 changes: 2 additions & 2 deletions autodetector.md
    View file
    Original file line number Diff line number Diff line change
    @@ -2,7 +2,7 @@

    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. If we use the flag `--no-input` it isn't enough as 2 scenarios still raise the questioner no matter what.

    ### Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`.
    #### Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`.

    When we send the flag `--no-input` to the `makemigrations` command it calls the non-interactive questioner.

    @@ -14,7 +14,7 @@ else:
    questioner = NonInteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
    ```

    ### `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in three methods.
    #### `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in three methods.

    [Source code](https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L227-L239):
    ```python
  8. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 7 additions and 5 deletions.
    12 changes: 7 additions & 5 deletions autodetector.md
    View file
    Original file line number Diff line number Diff line change
    @@ -2,7 +2,7 @@

    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. If we use the flag `--no-input` it isn't enough as 2 scenarios still raise the questioner no matter what.

    ## Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`.
    ### Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`.

    When we send the flag `--no-input` to the `makemigrations` command it calls the non-interactive questioner.

    @@ -14,7 +14,7 @@ else:
    questioner = NonInteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
    ```

    ## `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in two methods.
    ### `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in three methods.

    [Source code](https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L227-L239):
    ```python
    @@ -35,7 +35,7 @@ class NonInteractiveMigrationQuestioner(MigrationQuestioner):

    With thit in mind, if we want to prevent a exit code other than 0 (successful exit) we have to avoid the call of the 3 following methods.

    ## `ask_auto_now_add_addition` and `ask_not_null_addition`
    #### `ask_auto_now_add_addition` and `ask_not_null_addition`

    This is from [where](https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py#L860-L871) they can be called:
    ```python
    @@ -53,7 +53,7 @@ if not preserve_default:
    field.default = self.questioner.ask_not_null_addition(field_name, model_name)
    ```

    ## `ask_not_null_alteration`
    #### `ask_not_null_alteration`

    This is from [where](https://github.com/django/django/blob/5931d2e96ae94b204d146b7f751e0e804da74953/django/db/migrations/autodetector.py#L959-L962) it can be called:
    ```python
    @@ -92,7 +92,9 @@ def ask_not_null_alteration(self, field_name, model_name):
    return None
    ```

    **TL;DR**:
    #### TL;DR

    The magic sauce:

    ```python
    # When creating fields
  9. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 32 additions and 16 deletions.
    48 changes: 32 additions & 16 deletions autodetector.md
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    @@ -1,6 +1,10 @@
    ## Introduction

    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. If we use the flag `--no-input` it isn't enough as 2 scenarios still raise the questioner no matter what.

    Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`. When we send the flag `--no-input` to the `makemigrations` command it calls the non-interactive questioner.
    ## Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`.

    When we send the flag `--no-input` to the `makemigrations` command it calls the non-interactive questioner.

    [Source code](https://github.com/django/django/blob/290d8471bba35980f3e228f9c171afc40f2550fa/django/core/management/commands/makemigrations.py#L135-L138):
    ```python
    @@ -10,8 +14,7 @@ else:
    questioner = NonInteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
    ```


    `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in two methods.
    ## `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in two methods.

    [Source code](https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L227-L239):
    ```python
    @@ -30,13 +33,11 @@ class NonInteractiveMigrationQuestioner(MigrationQuestioner):
    sys.exit(3)
    ```

    With that in mind, if we want to prevent a exit code other than 0 (successful exit) we have to avoid the call of:
    - `ask_auto_now_add_addition`
    - `ask_not_null_addition`
    With thit in mind, if we want to prevent a exit code other than 0 (successful exit) we have to avoid the call of the 3 following methods.

    `ask_not_null_alteration` doesn't fail but expects us to have a sql script to run after to set all records field value to NULL.
    ## `ask_auto_now_add_addition` and `ask_not_null_addition`

    [Source code](https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py#L860-L871):
    This is from [where](https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py#L860-L871) they can be called:
    ```python
    time_fields = (models.DateField, models.DateTimeField, models.TimeField)
    preserve_default = (
    @@ -52,17 +53,18 @@ if not preserve_default:
    field.default = self.questioner.ask_not_null_addition(field_name, model_name)
    ```

    **TL;DR**: Above is all the logic Django uses to check if the questioner should display or not. Checks such as is the field nullable? Does the field have a default? We could do the same checks and rest assured that the non-interactive makemigrations never fails. I also suggested earlier that if the request to the model builder fails this very same checks that the API should reply with an error stating that something more is required (whatever is missing).
    ## `ask_not_null_alteration`

    **UPDATE:**

    This [check](
    https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py#L957-L958) should also be made:
    This is from [where](https://github.com/django/django/blob/5931d2e96ae94b204d146b7f751e0e804da74953/django/db/migrations/autodetector.py#L959-L962) it can be called:
    ```python
    if (old_field.null and not new_field.null and not new_field.has_default() and not new_field.many_to_many):
    if (old_field.null and not new_field.null and not new_field.has_default() and
    not new_field.many_to_many):
    field = new_field.clone()
    new_default = self.questioner.ask_not_null_alteration(field_name, model_name)
    ```

    To avoid the call of `ask_not_null_alteration`. The [source code](https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L166-L177) explains why this is a good idea, because the non-interactive way always runs the `NOT_PROVIDED` option - `Ignore for now..`:
    This one doesn't return `sys.exit(3)`, instead it defaults to the `NOT_PROVIDED` option just as we chose `Ignore for now..` option.
    This [Source Code](https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L166-L177) explains why its a good idea to avoid it too, check the message:
    ```python
    def ask_not_null_alteration(self, field_name, model_name):
    """Changing a NULL field to NOT NULL."""
    @@ -88,4 +90,18 @@ def ask_not_null_alteration(self, field_name, model_name):
    else:
    return self._ask_default()
    return None
    ```
    ```

    **TL;DR**:

    ```python
    # When creating fields
    field.null or field.has_default() or field.many_to_many or (field.blank and field.empty_strings_allowed) or (isinstance(field, time_fields) and field.auto_now)

    # When updating fields
    old_field.null and not new_field.null and not new_field.has_default() and not new_field.many_to_many
    ```

    Above is all the logic Django uses to check if the questioner should display or not. We could do the same checks and rest assured that the non-interactive makemigrations never fails.

    I also suggested earlier that if the request to the model builder fails this very same checks that the API should reply with an error stating that something more is required (whatever is missing).
  10. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion autodetector.md
    View file
    Original file line number Diff line number Diff line change
    @@ -62,7 +62,7 @@ https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py
    if (old_field.null and not new_field.null and not new_field.has_default() and not new_field.many_to_many):
    ```

    To avoid the call of `ask_not_null_alteration`. The [source code](https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L166-L177) explains why this is a good idea:
    To avoid the call of `ask_not_null_alteration`. The [source code](https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L166-L177) explains why this is a good idea, because the non-interactive way always runs the `NOT_PROVIDED` option - `Ignore for now..`:
    ```python
    def ask_not_null_alteration(self, field_name, model_name):
    """Changing a NULL field to NOT NULL."""
  11. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 27 additions and 1 deletion.
    28 changes: 27 additions & 1 deletion autodetector.md
    View file
    Original file line number Diff line number Diff line change
    @@ -62,4 +62,30 @@ https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py
    if (old_field.null and not new_field.null and not new_field.has_default() and not new_field.many_to_many):
    ```

    To avoid the call of `ask_not_null_alteration`.
    To avoid the call of `ask_not_null_alteration`. The [source code](https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L166-L177) explains why this is a good idea:
    ```python
    def ask_not_null_alteration(self, field_name, model_name):
    """Changing a NULL field to NOT NULL."""
    if not self.dry_run:
    choice = self._choice_input(
    "You are trying to change the nullable field '%s' on %s to non-nullable "
    "without a default; we can't do that (the database needs something to "
    "populate existing rows).\n"
    "Please select a fix:" % (field_name, model_name),
    [
    ("Provide a one-off default now (will be set on all existing "
    "rows with a null value for this column)"),
    ("Ignore for now, and let me handle existing rows with NULL myself "
    "(e.g. because you added a RunPython or RunSQL operation to handle "
    "NULL values in a previous data migration)"),
    "Quit, and let me add a default in models.py",
    ]
    )
    if choice == 2:
    return NOT_PROVIDED
    elif choice == 3:
    sys.exit(3)
    else:
    return self._ask_default()
    return None
    ```
  12. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 5 additions and 2 deletions.
    7 changes: 5 additions & 2 deletions autodetector.md
    View file
    Original file line number Diff line number Diff line change
    @@ -56,7 +56,10 @@ if not preserve_default:

    **UPDATE:**

    This check should also be made:
    https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py#L957-L958
    This [check](
    https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py#L957-L958) should also be made:
    ```python
    if (old_field.null and not new_field.null and not new_field.has_default() and not new_field.many_to_many):
    ```

    To avoid the call of `ask_not_null_alteration`.
  13. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 8 additions and 1 deletion.
    9 changes: 8 additions & 1 deletion autodetector.md
    View file
    Original file line number Diff line number Diff line change
    @@ -52,4 +52,11 @@ if not preserve_default:
    field.default = self.questioner.ask_not_null_addition(field_name, model_name)
    ```

    **TL;DR**: Above is all the logic Django uses to check if the questioner should display or not. Checks such as is the field nullable? Does the field have a default? We could do the same checks and rest assured that the non-interactive makemigrations never fails. I also suggested earlier that if the request to the model builder fails this very same checks that the API should reply with an error stating that something more is required (whatever is missing).
    **TL;DR**: Above is all the logic Django uses to check if the questioner should display or not. Checks such as is the field nullable? Does the field have a default? We could do the same checks and rest assured that the non-interactive makemigrations never fails. I also suggested earlier that if the request to the model builder fails this very same checks that the API should reply with an error stating that something more is required (whatever is missing).

    **UPDATE:**

    This check should also be made:
    https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py#L957-L958

    To avoid the call of `ask_not_null_alteration`.
  14. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 31 additions and 3 deletions.
    34 changes: 31 additions & 3 deletions autodetector.md
    View file
    Original file line number Diff line number Diff line change
    @@ -1,13 +1,19 @@
    This gist proposes a solution to this issue by doing the same checks Django uses to either ask further questions during migrations creation or not. Currently our background job stays in a loop because we don't provide a valid answer to this questioner. If we use the flag `--no-input` it isn't enough as 2 scenarios still raise the questioner no matter what.

    Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`. When we send the flag `--no-input` to the `makemigrations` command it calls the non-interactive questioner.

    [Source code](https://github.com/django/django/blob/290d8471bba35980f3e228f9c171afc40f2550fa/django/core/management/commands/makemigrations.py#L135-L138):
    ```python
    if self.interactive:
    questioner = InteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
    else:
    questioner = NonInteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
    ```
    https://github.com/django/django/blob/290d8471bba35980f3e228f9c171afc40f2550fa/django/core/management/commands/makemigrations.py#L135-L138

    `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in two methods:

    `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in two methods.

    [Source code](https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L227-L239):
    ```python
    class NonInteractiveMigrationQuestioner(MigrationQuestioner):

    @@ -24,4 +30,26 @@ class NonInteractiveMigrationQuestioner(MigrationQuestioner):
    sys.exit(3)
    ```

    https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L227-L239
    With that in mind, if we want to prevent a exit code other than 0 (successful exit) we have to avoid the call of:
    - `ask_auto_now_add_addition`
    - `ask_not_null_addition`

    `ask_not_null_alteration` doesn't fail but expects us to have a sql script to run after to set all records field value to NULL.

    [Source code](https://github.com/django/django/blob/2.2.5/django/db/migrations/autodetector.py#L860-L871):
    ```python
    time_fields = (models.DateField, models.DateTimeField, models.TimeField)
    preserve_default = (
    field.null or field.has_default() or field.many_to_many or
    (field.blank and field.empty_strings_allowed) or
    (isinstance(field, time_fields) and field.auto_now)
    )
    if not preserve_default:
    field = field.clone()
    if isinstance(field, time_fields) and field.auto_now_add:
    field.default = self.questioner.ask_auto_now_add_addition(field_name, model_name)
    else:
    field.default = self.questioner.ask_not_null_addition(field_name, model_name)
    ```

    **TL;DR**: Above is all the logic Django uses to check if the questioner should display or not. Checks such as is the field nullable? Does the field have a default? We could do the same checks and rest assured that the non-interactive makemigrations never fails. I also suggested earlier that if the request to the model builder fails this very same checks that the API should reply with an error stating that something more is required (whatever is missing).
  15. danielsousaio revised this gist Sep 27, 2019. 1 changed file with 2 additions and 3 deletions.
    5 changes: 2 additions & 3 deletions autodetector.md
    View file
    Original file line number Diff line number Diff line change
    @@ -1,6 +1,5 @@
    Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`. When we send the flag `--no-input` to the `makemigrations` command it calls the non-interactive questioner.

    ```
    ```python
    if self.interactive:
    questioner = InteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
    else:
    @@ -9,7 +8,7 @@ else:
    https://github.com/django/django/blob/290d8471bba35980f3e228f9c171afc40f2550fa/django/core/management/commands/makemigrations.py#L135-L138

    `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in two methods:
    ```
    ```python
    class NonInteractiveMigrationQuestioner(MigrationQuestioner):

    def ask_not_null_addition(self, field_name, model_name):
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    Calling `makemigrations` can call either `InteractiveMigrationQuestioner` or `NonInteractiveMigrationQuestioner`. When we send the flag `--no-input` to the `makemigrations` command it calls the non-interactive questioner.

    ```
    if self.interactive:
    questioner = InteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
    else:
    questioner = NonInteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
    ```
    https://github.com/django/django/blob/290d8471bba35980f3e228f9c171afc40f2550fa/django/core/management/commands/makemigrations.py#L135-L138

    `NonInteractiveMigrationQuestioner` itself will return `sys.exit(3)` in two methods:
    ```
    class NonInteractiveMigrationQuestioner(MigrationQuestioner):

    def ask_not_null_addition(self, field_name, model_name):
    # We can't ask the user, so act like the user aborted.
    sys.exit(3)

    def ask_not_null_alteration(self, field_name, model_name):
    # We can't ask the user, so set as not provided.
    return NOT_PROVIDED

    def ask_auto_now_add_addition(self, field_name, model_name):
    # We can't ask the user, so act like the user aborted.
    sys.exit(3)
    ```

    https://github.com/django/django/blob/e90af8bad44341cf8ebd469dac57b61a95667c1d/django/db/migrations/questioner.py#L227-L239