safely | An ML driven NSFW moderator for Slack ‍️ | Machine Learning library

Background

After some struggle I have managed to create a cluster for Amazon DocumentDb. Now I want to write a simple python class that when instantiated returns a client connection and allows me to insert a document. Upon completion of inserting document it closes connection safely.

After some more struggle I managed to get the following to work.

MY CODE

From the book Java Concurrency In Practice:

To publish an object safely, both the reference to the object and the object’s state must be made visible to other threads at the same time. A properly constructed object can be safely published by:

• Initializing an object reference from a static initializer;
• Storing a reference to it into a volatile field or AtomicReference;
• Storing a reference to it into a final field of a properly constructed object; or
• Storing a reference to it into a field that is properly guarded by a lock.

My question is:

Why does the bullet point 3 have the constrain:"of a properly constructed object", but the bullet point 2 does not have?

Does the following code safely publish the map instance? I think the code meets the conditions of bullet point 2.

I have the following relationship entity for neo4j Graph Model using Spring data neo4j 6.1.1 to represent relationship like Person-BookedFor->Movie where i can use UUID string for node repositories (Person, Movie) but not for the following relationship Entity BookedFor.

Note: since the neo4j doc describes this neo4j doc ref

I’m trying to setup the emulator so I can develop the firebase functions safely before deploying them. I just noticed that some REST calls I’m doing now fails - anybody know if it is not possible to use the REST feature of the RealTime DB https://firebase.google.com/docs/reference/rest/database

I'm trying to hit it with this URL

http://localhost:9000/?ns=-default-rtdb/development/DISHES.json

because this is what I set the firebaseConfig.databaseURL to (suggested here by Google)

Bonus info: If I try to do a GET to the URL via postman it creates another database called fake-server (http://localhost:4000/database/fake-server: null) 🤔

I have a need to write some Lua code but having come from a C background some of the common practices and programming strategies seem unusual to me. That said I wrote some code that illustrates what I am having trouble with:

I need to define a method that serializes objects for storage, but the semantics of it require that it can only work with objects whose fields keys are of string type (because they must match the column's names, so they cannot be numbers).

Using a Record type won't work for this serializer input, because I am supplying it objects that have specific fields defined (like interface Foo {foo: number, bar: string} and these are not assignable to Record).

Same thing why we cannot do safely assign a List to a List if List is mutable, but we can if they are immutable .

So I need to either specify that a generic type parameter's keyof T is a subset of string or have a ReadOnlyRecord that is covariant with any interface that has string keys.

Suggestions?

I am making a website with ASP.net core MVC. I want the website just to have one admin login to manage a database that manages the layout of the page. How do I have only one use without Microsoft Identity that includes everything for a millon users. I just want to have one login for a user (me) to live edit a website layout via a database, everyone that visits the page should never have to login. Thanks beforehand!

/* UPDATE */

I have managed to successfully add a userprincipal to a user that logs in with the use of claims. I have a question: How do I safely store the passwords and how do I claim a password? What ClamType do I use for password validation?

Best regards Max

I am writing a small TCP sockets "library", and I ran into much trouble.

When something happens to the socket that causes it to be instantly closed and freed (regardless of background lingering, talking about user space here), which is only done within a locked mutex since the application I'm writing is multi-threaded, I need a way to tell all the other (potentially) waiting threads (on the same mutex) that want to do something with the socket: "I'm terribly sorry, but the socket has been destroyed and you cannot access it" so that they don't cause any segmentation fault or such.

The idea I had was: the mutex was part of the socket (socket = a structure that contains multiple things, including a mutex and a file descriptor) so I couldn't quite free the socket if other threads were waiting for it (undefined behavior), so the possible solution is to allocate the mutex, free the socket but not the mutex, set some flag (in the allocated memory) saying that the socket has been closed, and a counter so that the last thread waking up and getting notified that it cannot use the socket unlocks and destroys the mutex and frees the memory allocated. The mutex can still be accessed without segfault if we just store its pointer before acquiring the mutex (and the pointer won't ever change).

This solution has a fundamental problem though - what if between unlocking the mutex and freeing it by the last holder, the thread gets preempted and another one locks the mutex again (since you NEED to check socket-related stuff after you acquire the lock, so no way of knowing it got destroyed, unless you maybe use an atomic variable but then again, checking the atomic variable and locking the mutex as a whole are not an atomic operation). Or if you try to access the mutex on the already-freed socket. Undefined behavior emerges.

Any ideas how to solve this problem? I.e. how to destroy a socket so that other threads know about it to quit safely, and there are no race conditions? By quitting I mean aborting the socket function they were in, not cancelling or stopping the threads themselves.

i have tried many sites and am really struggling as i cant seem to understand the VBA code

tab1 = data from C8:Rx? ... the data will continously grow so table will get bigger all the time

Column C in tab1 contains dates 21/05/2021

I want to be able to have 2 prompt boxes where i enter a date from and date to 21/05/2021 - 22/05/2021

when i action the macro it will take only the data from the table in tab1 in between these dates

and paste them in tab2 at cell ref c8 (the start of the table)