PyQt5 和 Django：如何使用 HTTP 请求（Multipart-form）上传图像？
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【中文标题】PyQt5 和 Django：如何使用 HTTP 请求（Multipart-form）上传图像？【英文标题】：PyQt5 and Django : How to Upload Image using HTTP Request ( Multipart-form )? 【发布时间】：2019-03-12 19:50:46 【问题描述】：目前我正在一个项目中创建一个卖家应用程序，卖家可以在其中上传菜单图片和一些附加信息，例如价格和菜单名称。但我坚持使用 POST 请求方法，因为此时我必须上传带有一些文本数据的图像，而不仅仅是文本数据。
我正在使用 PyQt5。
这是我的 API 网络服务器。我正在使用 Django Rest Framework 来构建它。
[
这是菜单模型：
class Menu(models.Model):
image = models.ImageField(upload_to=path_and_rename)
name = models.CharField(max_length=100)
price = models.IntegerField()
category = models.IntegerField()
availability = models.BooleanField(default=False)
# booked = models.IntegerField()
sellerID = models.ForeignKey(Seller, on_delete=models.PROTECT)
这是菜单序列化程序：
class MenuSerializer(serializers.ModelSerializer):
class Meta:
model = models.Menu
fields = ('id', 'image', 'name', 'price',
'category','availability', 'sellerID')
这是菜单视图集：
class MenuViewset(viewsets.ModelViewSet):
queryset = models.Menu.objects.all()
serializer_class = serializers.MenuSerializer
我已经尝试过这个答案中的方法：here
这是我对该方法的实现：
def upload(self):
file1 = QFile("/home/shalahuddin/Desktop/jamu.jpg")
file1.open(QFile.ReadOnly)
url = "http://127.0.0.1:8000/api/menu/"
nama = QByteArray()
nama.append("ABCD")
harga = QByteArray()
harga.append(str(999))
kategori = QByteArray()
kategori.append(str(0))
ada = QByteArray()
ada.append(str(True))
idseller = QByteArray()
idseller.append(str(2))
data = "name": nama, "price": harga, "category": kategori, "availability": ada, "sellerID": idseller
files = "image": file1
multipart = self.construct_multipart(data, files)
request_qt = QNetworkRequest(QUrl(url))
request_qt.setHeader(QtNetwork.QNetworkRequest.ContentTypeHeader,
'multipart/form-data; boundary=%s' % multipart.boundary())
self.manager = QtNetwork.QNetworkAccessManager()
self.manager.finished.connect(self.handleResponseMenu)
self.manager.post(request_qt, multipart)
def handleResponseMenu(self, reply):
er = reply.error()
data = json.loads(str(reply.readAll(), 'utf-8'))
file = open("/home/shalahuddin/Desktop/testfile.txt", "w")
file.write(str(reply))
if er == QtNetwork.QNetworkReply.NoError:
bytes_string = reply.readAll()
data = json.loads(str(bytes_string, 'utf-8'))
# print(data)
QMessageBox.information(self, "Menu", "Upload Success!")
else:
errorMessage = "Error occured: " + str(er) + "\n" + str(reply.errorString())
QMessageBox.critical(self, "Error Done", errorMessage)
def construct_multipart(self, data, files):
multiPart = QHttpMultiPart(QHttpMultiPart.FormDataType)
for key, value in data.items():
textPart = QtNetwork.QHttpPart()
textPart.setHeader(QNetworkRequest.ContentDispositionHeader,
"form-data; name=\"%s\"" % key)
textPart.setBody(value)
multiPart.append(textPart)
for key, file in files.items():
imagePart = QtNetwork.QHttpPart()
# imagePart.setHeader(QNetworkRequest::ContentTypeHeader, ...);
fileName = QFileInfo(file.fileName()).fileName()
imagePart.setHeader(QtNetwork.QNetworkRequest.ContentDispositionHeader,
"form-data; name=\"%s\"; filename=\"%s\"" % (key, fileName))
imagePart.setBodyDevice(file)
multiPart.append(imagePart)
return multiPart
但是我得到了错误 302 Bad Request 结果。我得到的 JSON 数据是：
'image': ['No file was submitted.'],
'name': ['Ensure this field has no more than 100 characters.',
'Null characters are not allowed.'],
'price': ['This field is required.'],
'category': ['This field is required.'],
'sellerID': ['This field is required.']
因此，我想知道问题出在哪里？我试图反复追踪它，但仍然没有给出答案。这是我第一次使用多部分请求。
【问题讨论】：
如果我在正文中使用带有表单数据格式的 Post-man 测试服务器，它可以工作 @eyllanesc 当然，这里是代码：github.com/shalahuddinn/CanteenWebServer 【参考方案1】：在以下示例中，我将向您展示如何创建查询：
import json
from PyQt5 import QtCore, QtNetwork, QtWidgets
class MenuWidget(QtWidgets.QWidget):
def __init__(self, parent=None):
super(MenuWidget, self).__init__(parent)
self._manager = QtNetwork.QNetworkAccessManager()
self._manager.finished.connect(self.handleResults)
self.init_ui()
def init_ui(self):
self.filepath_lineedit = QtWidgets.QLineEdit()
select_button = QtWidgets.QPushButton(
text="Select File",
clicked=self.select_file
)
self.name_lineedit = QtWidgets.QLineEdit()
self.price_spinbox = QtWidgets.QSpinBox()
self.category_spinbox = QtWidgets.QSpinBox()
self.availability_checkbox = QtWidgets.QCheckBox()
self.seller_id_spinbox = QtWidgets.QSpinBox()
self.log_textedit = QtWidgets.QTextBrowser()
upload_button = QtWidgets.QPushButton(
text="Upload",
clicked=self.upload
)
hlay = QtWidgets.QHBoxLayout()
hlay.addWidget(self.filepath_lineedit)
hlay.addWidget(select_button)
lay = QtWidgets.QFormLayout(self)
lay.addRow("Image:", hlay)
lay.addRow("Name:", self.name_lineedit)
lay.addRow("Price:", self.price_spinbox)
lay.addRow("Category:", self.category_spinbox)
lay.addRow("Availability:", self.availability_checkbox)
lay.addRow("SellerID:", self.seller_id_spinbox)
lay.addRow(self.log_textedit)
lay.addRow(upload_button)
@QtCore.pyqtSlot()
def select_file(self):
filename, _ = QtWidgets.QFileDialog.getOpenFileName(
self,
"Open Image",
QtCore.QDir.currentPath(),
"Image Files (*.png *.jpg *.bmp)"
)
if filename:
self.filepath_lineedit.setText(filename)
@QtCore.pyqtSlot()
def upload(self):
data =
"name": self.name_lineedit.text(),
"price": self.price_spinbox.value(),
"category": self.category_spinbox.value(),
"availability": self.availability_checkbox.isChecked(),
"sellerID": self.seller_id_spinbox.value()
path = self.filepath_lineedit.text()
files = "image": path
multi_part = self.construct_multipart(data, files)
if multi_part:
url = QtCore.QUrl("http://127.0.0.1:8000/api/menu/")
request = QtNetwork.QNetworkRequest(url)
reply = self._manager.post(request, multi_part)
multi_part.setParent(reply)
@QtCore.pyqtSlot(QtNetwork.QNetworkReply)
def handleResults(self, reply):
parsed = json.loads(reply.readAll().data())
text = json.dumps(parsed, indent=4, sort_keys=True)
self.log_textedit.setText(text)
if reply.error() == QtNetwork.QNetworkReply.NoError:
QtWidgets.QMessageBox.information(self, "Menu", "Upload Success!")
else:
errorMessage = "Error occured: ".format(reply.errorString())
QMessageBox.critical(self, "Error Done", errorMessage)
reply.deleteLater()
def construct_multipart(self, data, files):
multi_part = QtNetwork.QHttpMultiPart(QtNetwork.QHttpMultiPart.FormDataType)
for key, value in data.items():
post_part = QtNetwork.QHttpPart()
post_part.setHeader(QtNetwork.QNetworkRequest.ContentDispositionHeader,
"form-data; name=\"\"".format(key))
post_part.setBody(str(value).encode())
multi_part.append(post_part)
for field, filepath in files.items():
file = QtCore.QFile(filepath)
if not file.open(QtCore.QIODevice.ReadOnly):
break
post_part = QtNetwork.QHttpPart()
post_part.setHeader(QtNetwork.QNetworkRequest.ContentDispositionHeader,
"form-data; name=\"\"; filename=\"\"".format(field, file.fileName()))
post_part.setBodyDevice(file)
file.setParent(multi_part)
multi_part.append(post_part)
return multi_part
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
w = MenuWidget()
w.show()
sys.exit(app.exec_())
【讨论】：
@eyllansec 嗨，兄弟，我只记得一件事，PATCH 请求是否可能？例如，我只想编辑数据（不上传新图片）。以上是关于PyQt5 和 Django：如何使用 HTTP 请求（Multipart-form）上传图像？的主要内容，如果未能解决你的问题，请参考以下文章