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Localhost Screenshot 我有以下要求:的Django不能分配,「Rating.exercise」必須是「鍛鍊」的實例
- 有練習和有收視率
- 的鍛鍊可以有多個等級
我的目標是動態地爲練習添加評分,也就是說,我已經創建了所有練習,然後對特定練習進行評分,之後我應該可以添加一些功能。當我打「save_rating」鑑於我得到錯誤「不能分配‘[]’:‘Rating.exercise’必須是‘鍛鍊’實例。」
我在做什麼錯?
我的models.py看起來像下面
class Exercise(models.Model):
#Field for storing exercise type
EXERCISE_TYPE_CHOICES = (
('BS', 'Best stretch'),
('BR', 'Butterfly reverse'),
('SR', 'Squat row'),
('PL', 'Plank'),
('PU', 'Push up'),
('SP', 'Side plank'),
('SQ', 'Squat'),
)
exercise_type = models.CharField(max_length=5,choices=EXERCISE_TYPE_CHOICES)
#Field for storing intensity level
INTENSITY_LEVEL_CHOICES = (
(1, 'Really simple'),
(2, 'Rather Simple'),
(3, 'Simple'),
(4, 'Okay'),
(5, 'Difficult'),
(6, 'Rather Difficult'),
(7, 'Really Difficult'),
)
intensity_level = models.IntegerField(choices=INTENSITY_LEVEL_CHOICES)
#Field for storing video url for a particular exercise
video_url = models.URLField()
#Field for storing description of the exercise
description = models.CharField(max_length=500)
class Rating(models.Model):
#Field for storing exercise type
exercise = models.ForeignKey(Exercise, related_name='ratings', blank=True, null=True)
#Field for storing rating
RATING_CHOICES = (
('H', 'Happy'),
('N', 'Neutral'),
('S', 'Sad'),
)
value = models.CharField(max_length=1,choices=RATING_CHOICES)
我定義我的串行類似以下內容:
class RatingSerializer(serializers.Serializer):
class Meta:
model = Rating
fields = ('value')
class ExerciseSerializer(serializers.Serializer):
pk = serializers.IntegerField(read_only=True)
exercise_type = serializers.CharField(required=True, allow_blank=False)
intensity_level = serializers.IntegerField(required=True)
video_url = serializers.URLField(required=True)
description = serializers.CharField(required=True, allow_blank=False)
ratings = RatingSerializer(many=True, read_only=True)
我的觀點:
def exercise_list(request):
"""
List all exercises.
"""
if request.method == 'GET':
exercises = Exercise.objects.filter(exercise_type='BS', intensity_level=1)
serializer = ExerciseSerializer(exercises, many=True)
return JSONResponse(serializer.data)
def save_rating(request):
"""
Save a rating for a specific exercise.
"""
#Get a specific exercise for which you want to save the rating
specificExercise = Exercise.objects.filter(exercise_type='BS' , intensity_level=1)
#Create a rating and pass the specific exercise reference to it
Rating.objects.create(exercise = specificExercise, value='H')
#serializer = ExerciseSerializer(rating, many=True)
serializer = ExerciseSerializer(instance=specificExercise)
return JSONResponse(serializer.data)
你能不能請告訴我它是如何修復的?我對Django比較陌生。 當我將自己的行修改爲 exercise = Exercise.objects.get(exercise_type ='BS',intensity_level = 1)時,它會在練習中創建兩個空白評分,但評分值即'H'未插入。 – Nitish
我編輯了我的答案。但我確實希望你明白爲什麼你的代碼不起作用。請閱讀更多django文檔以熟悉它並查看它是否有意義:https://docs.djangoproject.com/en/1.9/topics/db/queries/#retrieving-a-single-object-with-get –
當然!您的答案確實奏效,只是保存的評分是空白的。 Rating.objects.create(exercise = specificExercise,value ='H'),但值「H」不插入。 – Nitish