I have a website with these models:
class TrainingSession(models.Model):
user = models.ForeignKey(user)
active_exercise = models.ForeignKey(Exercise)
class Passage(models.Model):
text = models.TextField()
class Exercise(models.Model):
training_session = models.ForeignKey(TrainingSession)
passage = models.ForeignKey(Passage)
where a user is assigned a TrainingSession that generates exercises of passages.
The general idea of the website is to give users reading exercises to work on. But I want to generate new exercises with passages the users haven't read yet during their current session. So to that end, the TrainingSession class has this method:
# this passes
def generate_exercise(self):
passages = Passage.objects.exclude(exercise__trainingsession=self)
if not passages:
raise ObjectDoesNotExist()
passage = random.choice(passages)
new_exercise = Exercise.objects.create(training_session=self,
passage=passage)
self.active_exercise = new_exercise
So if I tried to generate an exercise before creating any passages, you'd expect an ObjectDoesNotExist to be raised. And that's exactly what happens in this test:
# this test passes
def test_no_passages(self):
Passage.objects.all().delete()
user = User.objects.create()
session = TrainingSession.objects.create(user=user)
with self.assertRaises(ObjectDoesNotExist):
session.generate_exercise()
And if I have one passage, and generate the exercise, it works:
# this test passes
def test_generate_one(self):
Passage.objects.all().delete()
user = User.objects.create()
session = TrainingSession.objects.create(user=user)
Passage.objects.create(passage_title='a', passage_text='b')
session.generate_exercise()
And if I have one passage, and try to generate two exercises in a row, it raises the exception, as I'd hoped:
# this test passes
def test_cant_generate_second(self):
Passage.objects.all().delete()
user = User.objects.create()
session = TrainingSession.objects.create(user=user)
Passage.objects.create(passage_title='a', passage_text='b')
session.generate_exercise()
with self.assertRaises(ObjectDoesNotExist):
session.generate_exercise()
But then if I have TWO passages, and try to generate THREE exercises, no error gets raised and this following test fails:
# never raises the exception and fails
def test_cant_generate_third(self):
Passage.objects.all().delete()
user = User.objects.create()
session = TrainingSession.objects.create(user=user)
Passage.objects.create(passage_title='a', passage_text='b')
Passage.objects.create(passage_title='c', passage_text='d')
session.generate_exercise()
session.generate_exercise()
with self.assertRaises(ObjectDoesNotExist):
session.generate_exercise()
And if I print out what should be the 'used' passages:
print 'used:', [ex.passage for ex in
Exercise.objects.filter(trainingsession=session)]
at different points in the last test, something weird happens. At first it's empty, when I haven't generated any exercises. After I generate the first exercise, it prints out an array with the passage attached to the first generated exercise. But when I generate a second exercise, it ONLY SHOWS THE NEWEST EXERCISES'S PASSAGE. So somehow,
Exercise.objects.filter(trainingsession=session)
is only finding the latest created exercise, and not all the exercises that I've created pointing to the given training session.
So my question is: might there be a reason why the line:
new_exercise = Exercise.objects.create(training_session=self,
passage=passage)
might cause this later query:
passages = Passage.objects.exclude(exercise__trainingsession=self)
to misbehave?
I already tried:
new_exercise.save() # --doesn't help
Or, if that question doesn't have an obvious answer, my follow up: can you see what I'm doing wrong?
Figured it out:
passages = Passage.objects.exclude(exercise__trainingsession=self)
should be
passages = Passage.objects.exclude(exercise__training_session=self)
Using
exercise__trainingsession
was following the reverse path from TrainingSession to Exercise through TrainingSession's active_exercise foreign key, so only the 'active' exercise was being excluded.
Related
I'm developing an Android application with backend developed using Tastypie and Django. I have a get request for which I want to optionally be able to retrieve the entire object (with complete related fields, rather than URIs). Below is part of the python code for the resource I'm talking about:
class RideResource(ModelResource):
user = fields.ForeignKey(UserResource, 'driver')
origin = fields.ForeignKey(NodeResource, 'origin', full=True)
destination = fields.ForeignKey(NodeResource, 'destination', full=True)
path = fields.ForeignKey(PathResource, 'path')
# if the request has full_path=1 then we perform a deep query, returning the entire path object, not just the URI
def dehydrate(self, bundle):
if bundle.request.GET.get('full_path') == "1":
self.path.full = True
else:
ride_path = bundle.obj.path
try:
bundle.data['path'] = _Helpers.serialise_path(ride_path)
except ObjectDoesNotExist:
bundle.data['path'] = []
return bundle
As you can see the RideResource has a foreign key pointing to PathResource. I'm using the dehydrate function to be able to inspect if the GET request has a parameter "full_path" set to 1. In that case I set programmatically the path variable to full=True. Otherwise I simply return the path URI.
The thing is that the code seems to work only the second time the GET is performed. I've tested it hundreds of times and, when I perform my GET with full_path=1, even tho it enters the if and sets self.path.full = True, the first time it only returns the URI of the PathResource object. While, if I relaunch the exact same request a second time it works perfectly...
Any idea what's the problem?
EDIT AFTER SOLUTION FOUND THANKS TO #Tomasz Jakub Rup
I finally managed to get it working using the following code:
def full_dehydrate(self, bundle, for_list=False):
self.path.full = bundle.request.GET.get('full_path') == "1"
return super(RideResource, self).full_dehydrate(bundle, for_list)
def dehydrate(self, bundle):
if not bundle.request.GET.get('full_path') == "1":
try:
bundle.data['path'] = _Helpers.serialise_path(bundle.obj.path)
except ObjectDoesNotExist:
bundle.data['path'] = []
return bundle
dehydrate is called after full_dehydrate. Overwrite full_dehydrate function.
def full_dehydrate(self, bundle, for_list=False):
self.path.full = bundle.request.GET.get('full_path') == "1"
return super(RideResource, self).full_dehydrate(bundle, for_list)
Im new to python and figured that best way to learn is by practice, this is my first project.
So there is this fantasy football website. My goal is to create script which logins to site, automatically creates preselected team and submits it.
I have managed to get to submitting team part.
When I add a team member this data gets sent to server:
https://i.gyazo.com/e7e6f82ca91e19a08d1522b93a55719b.png
When I press save this list this data gets sent:
https://i.gyazo.com/546d49d1f132eabc5e6f659acf7c929e.png
Code:
import requests
with requests.Session() as c:
gameurl = 'here is link where data is sent'
BPL = ['5388', '5596', '5481', '5587',
'5585', '5514', '5099', '5249', '5566', '5501', '5357']
GID = '168'
UDID = '0'
ACT = 'draft'
ACT2 = 'save_draft'
SIGN = '18852c5f48a94bf3ee58057ff5c016af'
# eleven of those with different BPL since 11 players needed:
c.get(gameurl)
game_data = dict(player_id = BPL[0], action = ACT, id = GID)
c.post(gameurl, data = game_data)
# now I need to submit my list of selected players:
game_data_save = dict( action = ACT2, id = GID, user_draft_id = UDID, sign = SIGN)
c.post(gameurl, data = game_data_save)
This code works pretty fine, but the problem is, that 'SIGN' is unique for each individual game and I have no idea how to get this data without using Chromes inspect option.
How can I get this data simply running python code?
Because you said you can find it using devtools I'm assuming SIGN is written somewhere in the DOM.
In that case you can use requests.get().text to get the HTML of the page and parse it with a tool like lxml or HTMLParser
Solved by posting all data without 'SIGN' and in return I got 'SIGN' in html.
I am trying to use endpoints to update some JSON values in my datastore. I have the following Datastore in GAE...
class UsersList(ndb.Model):
UserID = ndb.StringProperty(required=True)
ArticlesRead = ndb.JsonProperty()
ArticlesPush = ndb.JsonProperty()
In general what I am trying to do with the API is have the method take in a UserID and a list of articles read (with an article being represented by a dictionary holding an ID and a boolean field saying whether or not the user liked the article). My messages (centered on this logic) are the following...
class UserID(messages.Message):
id = messages.StringField(1, required=True)
class Articles(messages.Message):
id = messages.StringField(1, required=True)
userLiked = messages.BooleanField(2, required=True)
class UserIDAndArticles(messages.Message):
id = messages.StringField(1, required=True)
items = messages.MessageField(Articles, 2, repeated=True)
class ArticleList(messages.Message):
items = messages.MessageField(Articles, 1, repeated=True)
And my API/Endpoint method that is trying to do this update is the following...
#endpoints.method(UserIDAndArticles, ArticleList,
name='user.update',
path='update',
http_method='GET')
def get_update(self, request):
userID = request.id
articleList = request.items
queryResult = UsersList.query(UsersList.UserID == userID)
currentList = []
#This query always returns only one result back, and this for loop is the only way
# I could figure out how to access the query results.
for thing in queryResult:
currentList = json.loads(thing.ArticlesRead)
for item in articleList:
currentList.append(item)
for blah in queryResult:
blah.ArticlesRead = json.dumps(currentList)
blah.put()
for thisThing in queryResult:
pushList = json.loads(thisThing.ArticlesPush)
return ArticleList(items = pushList)
I am having two problems with this code. The first is that I can't seem to figure out (using the localhost Google APIs Explorer) how to send a list of articles to the endpoints method using my UserIDAndArticles class. Is it possible to have a messages.MessageField() as an input to an endpoint method?
The other problem is that I am getting an error on the 'blah.ArticlesRead = json.dumps(currentList)' line. When I try to run this method with some random inputs, I get the following error...
TypeError: <Articles
id: u'hi'
userLiked: False> is not JSON serializable
I know that I have to make my own JSON encoder to get around this, but I'm not sure what the format of the incoming request.items is like and how I should encode it.
I am new to GAE and endpoints (as well as this kind of server side programming in general), so please bear with me. And thanks so much in advance for the help.
A couple things:
http_method should definitely be POST, or better yet PATCH because you're not overwriting all existing values but only modifying a list, i.e. patching.
you don't need json.loads and json.dumps, NDB does it automatically for you.
you're mixing Endpoints messages and NDB model properties.
Here's the method body I came up with:
# get UsersList entity and raise an exception if none found.
uid = request.id
userlist = UsersList.query(UsersList.UserID == uid).get()
if userlist is None:
raise endpoints.NotFoundException('List for user ID %s not found' % uid)
# update user's read articles list, which is actually a dict.
for item in request.items:
userslist.ArticlesRead[item.id] = item.userLiked
userslist.put()
# assuming userlist.ArticlesPush is actually a list of article IDs.
pushItems = [Article(id=id) for id in userlist.ArticlesPush]
return ArticleList(items=pushItems)
Also, you should probably wrap this method in a transaction.
My question concerns a class that I am writing that may or may not be fully initialized. The basic goal is to take a match_id and open the corresponding match_url (example: http://dota2lounge.com/match?m=1899) and then grab some properties out of the webpage. The problem is some match_ids will result in 404 pages (http://dota2lounge.com/404).
When this happens, there won't be a way to determine the winner of the match, so the rest of the Match can't be initialized. I have seen this causing problems with methods of the Match, so I added the lines to initialize everything to None if self._valid_url is False. This works in principal, but then I'm adding a line each time a new attribute is added, and it seems prone to errors down the pipeline (in methods, etc.) It also doesn't alert the user that this class wasn't properly initialized. They would need to call .is_valid_match() to determine that.
tl;dr: What is the best way to handle classes that may be only partially initiated? Since this is a hobby project and I'm looking to learn, I'm open to pretty much any solutions (trying new things), including other classes or whatever. Thanks.
This is an abbreviated version of the code containing the relevant portions (Python 3.3):
from urllib.request import urlopen
from bs4 import BeautifulSoup
class Match(object):
def __init__(self, match_id):
self.match_id = match_id
self.match_url = self.__determine_match_url__()
self._soup = self.__get_match_soup__()
self._valid_match_url = self.__determine_match_404__()
if self._valid_match_url:
self.teams, self.winner = self.__get_teams_and_winner__()
# These lines were added, but I'm not sure if this is correct.
else:
self.teams, self.winner = None, None
def __determine_match_url__(self):
return 'http://dota2lounge.com/match?m=' + str(self.match_id)
def __get_match_soup__(self):
return BeautifulSoup(urlopen(self.match_url))
def __get_match_details__(self):
return self._soup.find('section', {'class': 'box'})
def __determine_match_404__(self):
try:
if self._soup.find('h1').text == '404':
return False
except AttributeError:
return True
def __get_teams_and_winner__(self):
teams = [team.getText() for team in
self._soup.find('section', {'class': 'box'}).findAll('b')]
winner = False
for number, team in enumerate(teams):
if ' (win)' in team:
teams[number] = teams[number].replace(' (win)', '')
winner = teams[number]
return teams, winner
def is_valid_match(self):
return all([self._valid_match_url, self.winner])
I would raise an exception, handle that in your creation code (wherever you call some_match = Match(match_id)), and probably don't add it to whatever list you may or may not be using...
For a better answer, you might want to include in your question the code that instantiates all your Match objects.
I have this datastore model
class Project(db.Model)
projectname = db.StringProperty()
projecturl = db.StringProperty()
class Task(db.Model)
project = db.ReferenceProperty(Project)
taskname= db.StringProperty()
taskdesc = db.StringProperty()
How do I edit the value of taskname ? say I have task1 and i want to change it to task1-project
oops sorry, Here is the formatted code:
taskkey = self.request.get("taskkey")
taskid = Task.get(taskkey)
query = db.GqlQuery("SELECt * FROM Task WHERE key =:taskid", taskid=taskid)
if query.count() > 0:
task = Task()
task.taskname = "task1-project"
task.put()
by the way, I get it now. I changed the task=Task() into task = query.get() and it worked.
Thanks for helping by the way.
Given an instance t of Task (e.g. from some get operation on the db) you can perform the alteration you want e.g. by t.taskname = t.taskname + '-project' (if what you want is to "append '-project' to whatever was there before). Eventually, you also probably need to .put t back into the store, of course (but if you make multiple changes you don't need to put it back after each and every change -- only when you're done changing it!-).
Probably the easiest way is to use the admin console. Locally it's:
http://localhost:8080/_ah/admin
and if you've uploaded it, it's the dashboard:
http://appengine.google.com/dashboard?&app_id=******
Here's a link: