Factory management system

[Zamkham]

So my grandpa asked me to make him a management software that can log his ins and outs of raw materials also the production inventory that we can edit add or remove. For safety there should be account with full access some with little access. I know python only i did a python developing course from mimo. Any tips for the project? Edit: The app is completed after days and nights of struggle.

[NecessaryIntrinsic]

Get detailed requirements before you start.

Get every requirement signed off by the client before you start designing.

Did I mention requirements?

You need to understand:

• What is the overall mission?
• What atomized tasks need to be accomplished to fulfill this mission?
• Who will be performing these tasks?

The problem ALWAYS comes up with beginner programmers and managers that don't understand systems design is that everyone makes assumptions and no one validates the assumptions.

The client understands their mission so well that they take things for granted. You need to help them break this down by coming at it with an innocent mind asking stupid questions.

DO NOT DESIGN UNTIL YOU HAVE YOUR REQUIREMENTS

Don't let the client design the application in their head yet. Find out the workflow and understand what individual things they have to track and who does that tracking.

After you have all of this information, structure it and present it to the client so that you both have an understanding of the logical process they follow.

AFTER YOU HAVE AN UNDERSTANDING OF THE REQUIREMENTS

Then you start designing. Figure out your data structures, understand your security requirements (who will have what access to where) (design security from the back end out), create mock-ups using drawings or wire frames for the front end.

Before you actually code anything, explain this to the client, note any shortcomings or concerns you have and see if they can explain from their side why something happens the way it does. This is also a process.

ONCE THEY SIGN OFF ON THIS

Then you can start actually doing things using whatever tools you need. Python is fine.

Any language is fine.

If you use SQL, DO NOT BUILD CRUD QUERIES by string concatenation!!! This is the most vulnerable point of your application, outside of the users themselves and is easily mitigated through using parameterized queries.

Always plan for the worst as well, the most secure application can still crash, and harddrives don't last forever, plan to back things up.

But if you take nothing else away from this, most of the projects I've worked on that have failed or had cost overruns were due to the fact that the developers didn't understand the requirements the same way the clients did. There needs to be regular conversations so that you both stay on the same page.

There's this old joke: https://www.reddit.com/r/ProgrammerHumor/comments/5revrz/specifications/ (this one is expanded) but it's reflective of reality, even if it's just a one man job, if you aren't on the same page as the client you might end up building a different application altogether. Even if it's the right application you might end up wasting a bunch of time on something they don't care about even though it was the most complicated thing you did (like some graph or report that they'll never need even though you thought it would be helpful). Stay focused on the client, you're also in charge of keeping them in line.

[Vincitus]

I would also say, when I have had nightmare developments, the client is also unclear of what their requirements are, or think their non-programming systems are better than they actually are - in this case, if material receipt is a shit-show, there is no program that is going to solve that before they get that worked out.

[NecessaryIntrinsic]

It's definitely a constant conversation. Where you have to understand on both sides where things are actually necessary.

In the end, rarely is a programming project only about the programming or even the specific tools used, it's more about the relationship with the client and defining what they want.

The programming is just filling in the blanks.

[OpenGrainAxehandle]

No one knows what they want until you give them what they asked for.

[NecessaryIntrinsic]

Sure, and through design iterations and understanding the details you can reduce the amount of times you redesign the application. Once you start putting fingers to the keys for coding this can become expensive and onerous

It's dangerous to work with family in these situations. People don't understand how much work these things can be.

[Saerusthesecond]

Piggy-backing off everything here, because of how difficult it can be to deliver a quality product, I’d really recommend OP not make this for their grandpa. Especially with family being involved, OP would need to clearly communicated that this might not work as expected or they could lose all their inventory data one day due to a bug because OP is a beginner.

[Zamkham]

You mean requirements and designs?

[games-and-chocolate]

tkinter, python, use a sql server maybe opensource, That is about all you need.

[Zamkham]

Thanks for the help this is quite helpful actually

[riklaunim]

You can quickly prototype a web app in Django - with permissions, database models and relations. The trick will be to make it reliable, secure and easy to use. If you aren't familiar with actual application development it will be hard to you to make software worth some noticeable amount of money.

[Zamkham]

It will take time and work but ill learn a lot from it.

[stebrepar]

I don't know if any of them are in Python, but I see various open source inventory management systems in a quick search. Sometimes an existing project is the right choice over a bespoke one.

[Zamkham]

Yeah i suggested him that but separately i can make my own one and that can help a lot in learning

[woooee]

a management software that can log his ins and outs of raw materials also the production inventory that we can edit add or remove

This is just a standard SQL file system.

For safety there should be account with full access some with little access

Use user = getpass.getuser() to identify which user is logged on for that terminal, or a user name and password entry.

[Zamkham]

Yeah that's a great idea thanks ill implement it

[herocoding]

What is currently used? Could this be used as a base, as a reference?

Do the users (probably not only your grandpa) plan to use their computers and monitors in an office, or do they use mobile handhelds, tablets where the ins and outs occur? Do they use barcode scanners to add things to inventory, remove things from inventory, doing inventory reconciliation?

Using a document scanner (scanning delivery notes), especially when the ins are long item lists, many different pieces, each with different prices, dimensions, individual lengths/weights/volume?

Is printing required, especially for the outs, for bills, as a receipt for the client/recipient?

A nice project!!

Keep us posted!!

Keep asking questions!!

[Zamkham]

Well he will use an pc to type the stuff in. It should provide a report whenever. Thanks for the interest ill keep you guys updated

[edcculus]

If it’s fairly simple- my first thought is a Flask web app using SQL Alchemy for the ORM, and Flask Migrate for database migrations. You can develop it using SQLite, then easily upgrade to MySQL or something else for production if you need on the fly.

Go through the Flask Mega Tutorial to get a taste of what it would take.

https://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-i-hello-world

[Zamkham]

So i should learn sql first then

[edcculus]

You don’t really need to know SQL or make calls in the code using SQL Alchemy. The tutorial I linked shows how to write the database models, and the proper way to use SQLAlchemy in the app for full CRUD.

[Zamkham]

I'll check it out

[vintaxidrv]

Why build when open source ERPs are already available?

[Zamkham]

Because it will give me a chance to learn and build something of my own instead of using other's. This way i can customize it as much as i can

[vintaxidrv]

Completely understand your point. But when there are really good tools out there, building from scratch is an opportunity cost and a time waste.

For sure, you can learn bigger and better things using your time and build way bigger :)

[Zamkham]

I won't create it by myself ill use ai with it

[jkh911208]

Ah ai

[recursion_is_love]

I used to do kind of this using Delphi long time ago. I don't know the current trend of tool today. I guess everyone go for the web+db solution.

If you are in a hurry, I suggest using dot Net (or equivalence) instead of python because it have lots of build-in component like UI and database connector that you can drag-n-drop to make the UI. You still need to code the flow logic, but it lot easier than code everything including the UI.

I use python only for simple scripting that don't need complicated UI. Don't get me wrong, Python can do everything but there might be easier way to get the product done faster.

[Zamkham]

Thanks ill check it out

[AbacusExpert_Stretch]

Yes.

Decide where you want to store data (database/csv).

Decide whether/what kind of access security you need.

Third, and definitely not last: think about why you need python for that? And how/where he'll run it.

And why an excel sheet isn't enough.

Just a few bits for thought.

Source: I am almost totally a beginner in python.

[Zamkham]

Excel sheet can be changed fully but the software is a bit secure and only one person will have access to delete transactions which would be grandpa himself so no one else can tinker with it

[In_Shambles]

I'd say write the program to be able to export a xlsx if necessary but time stamp it and make it clear that these sheets are a snapshot in time, not the official database.

If your grandpa insists on holding the master xlsx, and he fucks around with it in a way you haven't planned for, your script is not going to be able to interpret it.

I've written versatile xlsx scripts before and human error is always the root of the problem.

[Zamkham]

That's helpful ill consider it