How Can I Check For The Existence of a UUID - python-3.x

I am trying to check for the existence of a UUID as a primary key in my Django environment...and when it exists...my code works fine...But if it's not present I get a "" is not a Valid UUID...
Here's my code....
uuid_exists = Book.objects.filter(id=self.object.author_pk,is_active="True").first()
I've tried other variations of this with .exists() or .all()...but I keep getting the ['“” is not a valid UUID.'] error.
I did come up with a workaround....
if self.object.author_pk is not '':
book_exists = Book.objects.filter(id=self.object.author_pk,is_active="True").first()
context['author_exists'] = author_exists
Is this the best way to do this? I was hoping to be able to use a straight filter...without clarifying logic....But I've worked all afternoon and can't seem to come up with anything better. Thanks in advance for any feedback or comments.

I've had the same issue and this is what I have:
Wrapping it into try/except (in my case it's a View so it's supposed to return a Response object)
try:
object = Object.objects.get(id=object_id)
except Exception as e:
return Response(data={...}, status=status.HTTP_40...
It gets to the exception (4th line) but somehow sends '~your_id~' is not a valid UUID. text instead of proper data. Which might be enough in some cases.
This seems like an overlook, so might as well get a fix soon. I don't have enough time to investigate deeper, unfortunately.
So the solution I came up with is not ideal either but hopefully is a bit cleaner and faster than what you're using rn.
# Generate a list of possible object IDs (make use of filters in order to reduce the DB load)
possible_ids = [str(id) for id in Object.objects.filter(~ filters here ~).values_list('id', flat=True)]
# Return an error if ID is not valid
if ~your_id~ not in possible_ids:
return Response(data={"error": "Database destruction sequence initialized!"}, status=status.HTTP_401_UNAUTHORIZED)
# Keep working with the object
object = Objects.objects.get(id=object_id)

Related

Update a parameter value in Brightway

It seems to be a simple question but I have a hard time to find an answer to it. I already have a project with several parameters (project and database parameters). I would like to obtain the LCA results for several scenarios with my parameters having different values each time. I was thinking of the following simple procedure:
change the parameters' value,
update the exchanges in my project,
calculate the LCA results.
I know that the answer should be in the documentation somewhere, but I have a hard time to understand how I should apply it to my ProjectParameters, DatabaseParameters and ActivityParameters.
Thanks in advance!
EDIT: Thanks to #Nabla, I was able to come up with this:
For ProjectParameter
for pjparam in ProjectParameter.select():
if pjparam.name=='my_param_name':
break
pjparam.amount = 3
pjparam.save()
bw.parameters.recalculate()
For DatabaseParameter
for dbparam in DatabaseParameter.select():
if dbparam.name=='my_param_name':
break
dbparam.amount = 3
dbparam.save()
bw.parameters.recalculate()
For ActivityParameter
for param in ActivityParameter.select():
if param.name=='my_param_name':
break
param.amount = 3
param.save()
param.recalculate_exchanges(param.group)
You could import DatabaseParameter and ActivityParameter iterate until you find the parameter you want to change, update the value, save it and recalculate the exchanges. I think you need to do it in tiers. First you update the project parameters (if any) then the database parameters that may depend on project parameters and then the activity parameters that depend on them.
A simplified case without project parameters:
from bw2data.parameters import ActivityParameter,DatabaseParameter
# find the database parameter to be updated
for dbparam in DatabaseParameter.select():
if (dbparam.database == uncertain_db.name) and (dbparam.name=='foo'):
break
dbparam.amount = 3
dbparam.save()
#there is also this method if foruma depend on something else
#dbparam.recalculate(uncertain_db.name)
# here updating the exchanges of a particular activity (act)
for param in ActivityParameter.select():
if param.group == ":".join(act.key):
param.recalculate_exchanges(param.group)
you may want to update all the activities in the project instead of a single one like in the example. you just need to change the condition when looping through the activity parameters.

How to get a certain (e.g. second or third) mention sent in a message

I've been trying to make a ship command that can either ship the author of the message with a mentioned user, or ship two mentioned users. I can get the 1st mention in a message but I have no idea on how to get the 2nd or even third mention in a message. I tried using:
message.mentions.users.first(2)
splitting the args then slicing them so only the second mention is avalaible, but this gives an "undefined" error when I try to get the username.
Could someone give me a script on exactly how to do it since I can't really get the hang of this
According to the documentation message.mentions.users yields a Collection. So you can just iterate over this collection or convert it to an array and then access the required index:
const userArray = message.mentions.users.array();
console.log(userArray[yourDesiredIndex]);

How to get all mentions from a message

I made a function which needs 2 mentions, so I first check the size with:
if (message.mentions.members.size == 2)
It works, but then I need to get both mentions. The following works, but it only gets me the first one:
message.mentions.members.first()
I've also tried other ways to get both mentions, like this one below, that returns undefined.
message.mentions.members[0]
first() takes an optional count parameter if you see here.
You can use this to return an array of the members, like so:
message.members.first(2);
The reason mentions.members[0] doesn't work is because members is a Collection (a discord.js enhancement of a map) which uses a snowflake as a key, 0 is not a valid snowflake and thus returns undefined.

How to translate error messages in Colander

How can I translate the error messages from the colander validators? The documentation just says that it's possible.
def valid_text(node, value):
raise Invalid(node, u"Some error message")
class form(colander.MappingSchema):
name = colander.SchemaNode(colander.String(), validator=valid_text)
I know that deform does it already but I need to use colander on his own.
According to the API documentation, the msg argument to Invalid can be a translation string instance. Information on working with translation strings is here.
Looks like this issue was already addressed and fixed, but it will be part of the next release. I've just added the changes from commit f6be836 and it works like a charm.

Subsonic BatchQuery.Queue causing 'Can't decide which property to consider the key...' exception

I'm just getting started with Subsonic 3.0 ActiveRecord and am trying to implement a batch query like the one in the SubSonic docs. I'm using a batch so I can query a User and a list of the users Orders in one shot.
When I call the BatchQuery.Queue() method, adding my "select user" query, SubSonic throws the following exception:
System.InvalidOperationException : Can't decide which property to consider the Key - you can create one called 'ID' or mark one with SubSonicPrimaryKey attribute
The code is as follows:
var db = new MyDB();
var userQuery = from u in db.Users //gets user by uid
where u.uid == 1
select u;
var provider = ProviderFactory.GetProvider();
var batch = new BatchQuery(provider);
batch.Queue(userQuery); //exception here
//create and add "select users orders" query here...
First things first - Why this error? My SubSonic Users object knows it's PK. "uid" is the PK in the database and the generated code reflects this. And I thought SubSonicPrimaryKey attribute was for the SimpleRepository? Is this way of batching not for ActiveRecord?
I could ask a number of other questions, but I'll leave it at that. If anyone can help me figure out what is going on and how to issue 2 batched queries I'd be grateful!
Edit - after further investigation
I ran through the source code with the debugger. Adam is correct - the ToSchemaTable() method in Objects.cs is apparently building out my schema and failing to find a PK. At the very end, it tries to find a column property named "ID" and flags this as the PK, otherwise it throws the exception. I added a check for "UID" and this works!
Still... I'm confused. I'm admittedly a bit lost after peeling back layer after layer of the source, but it seems like this portion of code is trying to build up a schema for my table and completely ignoring my generated User class - which quite nicely identifies which column/property is the PK! It doesn't seem quite right that I'd be required to name all keys "ID" w/ ActiveRecord.
I think the answer you're looking for is that this is a really stupid bug on my part. I'm hoping to push another build next week and if you could put this on the issue list I'd really appreciate it. My apologies...
SubSonic expects your primary key to be called Id so it's getting confused. SubSonicPrimaryKey is for simple repository but I assume where that exception is being thrown is shared between the different templates. If you rename your PK to Id or id or ID your query will work.

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