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How to use lambda function with dictionary?
How can I use lambda function with map for create a object? I receive 1 or more objects in my serializer by Json, then I want iterate this json and create a object. Here is my code from models.py, and my serializers.py.
# Models.py
class ModelA(models.Model):
...
@classmethod
def insert_car(self, i, user):
car = i.get('car')
item = i.get('item')
quantity = i.get('quantity')
ModelA.objects.create(user=user, car=car, item=item, quantity=quantity, status=self.STATUS_PENDING)
return True
# serializers.py
class ModelASerializer(ModelSerializer):
class Meta:
model = Order
fields = ['car', 'item', 'quantity']
class MultipleOrderSerializer(ModelSerializer):
items = ModelASerializer(many=True)
class Meta:
model = Order
fields = ['items']
def create(self, request, *args, **kwargs):
list = self.data.get('items')
user = self.context.get('request').user
a = map(lambda i : ModelA.insert_car(i, user), list)
return self.data
I tryed print anything inside my insert_car, but doesn't print nothing, the method insert_car doesn't called
#Update01
According to @bro-grammer, "In python 3 map is a lazy iterator. It doesnot do anything util you consume it. Try surrounding map(...) with list(map(...))"
then, the line calling map function looks like this:
create_car = list(map(lambda i : ModelA.insert_car(i, user), list))
python django django-models django-rest-framework django-serializer
asked Nov 22 '18 at 1:15
Matheus SoaresMatheus Soares
417
|
show 1 more comment
How can I use lambda function with map for create a object? I receive 1 or more objects in my serializer by Json, then I want iterate this json and create a object. Here is my code from models.py, and my serializers.py.
# Models.py
class ModelA(models.Model):
...
@classmethod
def insert_car(self, i, user):
car = i.get('car')
item = i.get('item')
quantity = i.get('quantity')
ModelA.objects.create(user=user, car=car, item=item, quantity=quantity, status=self.STATUS_PENDING)
return True
# serializers.py
class ModelASerializer(ModelSerializer):
class Meta:
model = Order
fields = ['car', 'item', 'quantity']
class MultipleOrderSerializer(ModelSerializer):
items = ModelASerializer(many=True)
class Meta:
model = Order
fields = ['items']
def create(self, request, *args, **kwargs):
list = self.data.get('items')
user = self.context.get('request').user
a = map(lambda i : ModelA.insert_car(i, user), list)
return self.data
I tryed print anything inside my insert_car, but doesn't print nothing, the method insert_car doesn't called
#Update01
According to @bro-grammer, "In python 3 map is a lazy iterator. It doesnot do anything util you consume it. Try surrounding map(...) with list(map(...))"
then, the line calling map function looks like this:
create_car = list(map(lambda i : ModelA.insert_car(i, user), list))
python django django-models django-rest-framework django-serializer
asked Nov 22 '18 at 1:15
Matheus SoaresMatheus Soares
417
1
I think yourcreatemethod signature should be likedef create(self, validated_data)
– bro-grammer
Nov 22 '18 at 1:23
What’s the difference? Can you explain to me??
– Matheus Soares
Nov 22 '18 at 1:55
It only accepts two arguments one isselfand other isvalidated_data. In your signature you are passing several different arguments.
– bro-grammer
Nov 22 '18 at 1:57
Because that the lambda map doesn’t work? If a use a for inside my insert_car its works normally. I don’t understand why lambda doesn’t work.
– Matheus Soares
Nov 22 '18 at 2:04
3
Oh i get it now. In python 3 map is a lazy iterator. It doesnot do anything util you consume it. Try surroundingmap(...)withlist(map(...))
– bro-grammer
Nov 22 '18 at 2:06
|
show 1 more comment
How can I use lambda function with map for create a object? I receive 1 or more objects in my serializer by Json, then I want iterate this json and create a object. Here is my code from models.py, and my serializers.py.
# Models.py
class ModelA(models.Model):
...
@classmethod
def insert_car(self, i, user):
car = i.get('car')
item = i.get('item')
quantity = i.get('quantity')
ModelA.objects.create(user=user, car=car, item=item, quantity=quantity, status=self.STATUS_PENDING)
return True
# serializers.py
class ModelASerializer(ModelSerializer):
class Meta:
model = Order
fields = ['car', 'item', 'quantity']
class MultipleOrderSerializer(ModelSerializer):
items = ModelASerializer(many=True)
class Meta:
model = Order
fields = ['items']
def create(self, request, *args, **kwargs):
list = self.data.get('items')
user = self.context.get('request').user
a = map(lambda i : ModelA.insert_car(i, user), list)
return self.data
I tryed print anything inside my insert_car, but doesn't print nothing, the method insert_car doesn't called
#Update01
According to @bro-grammer, "In python 3 map is a lazy iterator. It doesnot do anything util you consume it. Try surrounding map(...) with list(map(...))"
then, the line calling map function looks like this:
create_car = list(map(lambda i : ModelA.insert_car(i, user), list))
python django django-models django-rest-framework django-serializer
asked Nov 22 '18 at 1:15
Matheus SoaresMatheus Soares
417
How can I use lambda function with map for create a object? I receive 1 or more objects in my serializer by Json, then I want iterate this json and create a object. Here is my code from models.py, and my serializers.py.
# Models.py
class ModelA(models.Model):
...
@classmethod
def insert_car(self, i, user):
car = i.get('car')
item = i.get('item')
quantity = i.get('quantity')
ModelA.objects.create(user=user, car=car, item=item, quantity=quantity, status=self.STATUS_PENDING)
return True
# serializers.py
class ModelASerializer(ModelSerializer):
class Meta:
model = Order
fields = ['car', 'item', 'quantity']
class MultipleOrderSerializer(ModelSerializer):
items = ModelASerializer(many=True)
class Meta:
model = Order
fields = ['items']
def create(self, request, *args, **kwargs):
list = self.data.get('items')
user = self.context.get('request').user
a = map(lambda i : ModelA.insert_car(i, user), list)
return self.data
I tryed print anything inside my insert_car, but doesn't print nothing, the method insert_car doesn't called
#Update01
According to @bro-grammer, "In python 3 map is a lazy iterator. It doesnot do anything util you consume it. Try surrounding map(...) with list(map(...))"
then, the line calling map function looks like this:
create_car = list(map(lambda i : ModelA.insert_car(i, user), list))
python django django-models django-rest-framework django-serializer
python django django-models django-rest-framework django-serializer
asked Nov 22 '18 at 1:15
Matheus SoaresMatheus Soares
417
asked Nov 22 '18 at 1:15
Matheus SoaresMatheus Soares
417
edited Nov 22 '18 at 12:20
Matheus Soares
asked Nov 22 '18 at 1:15
Matheus SoaresMatheus Soares
417
asked Nov 22 '18 at 1:15
Matheus SoaresMatheus Soares
417
asked Nov 22 '18 at 1:15
Matheus SoaresMatheus Soares
417
417
1
I think yourcreatemethod signature should be likedef create(self, validated_data)
– bro-grammer
Nov 22 '18 at 1:23
What’s the difference? Can you explain to me??
– Matheus Soares
Nov 22 '18 at 1:55
It only accepts two arguments one isselfand other isvalidated_data. In your signature you are passing several different arguments.
– bro-grammer
Nov 22 '18 at 1:57
Because that the lambda map doesn’t work? If a use a for inside my insert_car its works normally. I don’t understand why lambda doesn’t work.
– Matheus Soares
Nov 22 '18 at 2:04
3
Oh i get it now. In python 3 map is a lazy iterator. It doesnot do anything util you consume it. Try surroundingmap(...)withlist(map(...))
– bro-grammer
Nov 22 '18 at 2:06
|
show 1 more comment
1
I think yourcreatemethod signature should be likedef create(self, validated_data)
– bro-grammer
Nov 22 '18 at 1:23
What’s the difference? Can you explain to me??
– Matheus Soares
Nov 22 '18 at 1:55
It only accepts two arguments one isselfand other isvalidated_data. In your signature you are passing several different arguments.
– bro-grammer
Nov 22 '18 at 1:57
Because that the lambda map doesn’t work? If a use a for inside my insert_car its works normally. I don’t understand why lambda doesn’t work.
– Matheus Soares
Nov 22 '18 at 2:04
3
Oh i get it now. In python 3 map is a lazy iterator. It doesnot do anything util you consume it. Try surroundingmap(...)withlist(map(...))
– bro-grammer
Nov 22 '18 at 2:06
1
1
I think your
create method signature should be like def create(self, validated_data)– bro-grammer
Nov 22 '18 at 1:23
I think your
create method signature should be like def create(self, validated_data)– bro-grammer
Nov 22 '18 at 1:23
What’s the difference? Can you explain to me??
– Matheus Soares
Nov 22 '18 at 1:55
What’s the difference? Can you explain to me??
– Matheus Soares
Nov 22 '18 at 1:55
It only accepts two arguments one is
self and other is validated_data. In your signature you are passing several different arguments.– bro-grammer
Nov 22 '18 at 1:57
It only accepts two arguments one is
self and other is validated_data. In your signature you are passing several different arguments.– bro-grammer
Nov 22 '18 at 1:57
Because that the lambda map doesn’t work? If a use a for inside my insert_car its works normally. I don’t understand why lambda doesn’t work.
– Matheus Soares
Nov 22 '18 at 2:04
Because that the lambda map doesn’t work? If a use a for inside my insert_car its works normally. I don’t understand why lambda doesn’t work.
– Matheus Soares
Nov 22 '18 at 2:04
3
3
Oh i get it now. In python 3 map is a lazy iterator. It doesnot do anything util you consume it. Try surrounding
map(...) with list(map(...))– bro-grammer
Nov 22 '18 at 2:06
Oh i get it now. In python 3 map is a lazy iterator. It doesnot do anything util you consume it. Try surrounding
map(...) with list(map(...))– bro-grammer
Nov 22 '18 at 2:06
|
show 1 more comment
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1
I think your
createmethod signature should be likedef create(self, validated_data)– bro-grammer
Nov 22 '18 at 1:23
What’s the difference? Can you explain to me??
– Matheus Soares
Nov 22 '18 at 1:55
It only accepts two arguments one is
selfand other isvalidated_data. In your signature you are passing several different arguments.– bro-grammer
Nov 22 '18 at 1:57
Because that the lambda map doesn’t work? If a use a for inside my insert_car its works normally. I don’t understand why lambda doesn’t work.
– Matheus Soares
Nov 22 '18 at 2:04
3
Oh i get it now. In python 3 map is a lazy iterator. It doesnot do anything util you consume it. Try surrounding
map(...)withlist(map(...))– bro-grammer
Nov 22 '18 at 2:06