𝗕𝘂𝗶𝗹𝗱𝗶𝗻𝗴 𝗮 𝗣𝗿𝗼𝗷𝗲𝗰𝘁 𝗠𝗮𝗻𝗮𝗴𝗲𝗺𝗲𝗻𝘁 𝗕𝗮𝗰𝗸𝗲𝗻𝗱
I am building a collaborative project management tool for my internship at CodeAlpha.
It works like a simplified Trello or Asana. Users create projects, invite members, and move tasks across boards. I use Express.js, Prisma, and Socket.io to power it.
Here are the technical lessons I learned while building the backend.
𝗠𝗮𝗻𝗮𝗴𝗶𝗻𝗴 𝗗𝗮𝘁𝗮 𝗥𝗲𝗹𝗮𝘁𝗶𝗼𝗻𝘀𝗵𝗶𝗽𝘀
Users and projects have a many-to-many relationship. I use a ProjectMember table to connect them. This table stores extra data like the user role.
I added a unique constraint to this table. This ensures a user appears only once per project. It also creates a composite key for fast lookups.
For the Kanban board, I kept things simple. A task status is defined by the board it belongs to. Moving a task from "To Do" to "Done" is just a matter of updating its board ID.
𝗔𝗿𝗰𝗵𝗶𝘁𝗲𝗰𝘁𝘂𝗿𝗲 𝗠𝗶𝘀𝘁𝗮𝗸𝗲𝘀
I learned a hard lesson about database connections. Do not create a new PrismaClient in every route file. This creates too many connections and crashes your app.
Instead, create one shared instance in a single file. Import that same instance into every route. This keeps your connection pool stable.
𝗔𝘂𝘁𝗵𝗼𝗿𝗶𝘇𝗮𝘁𝗶𝗼𝗻 𝗮𝗻𝗱 𝗦𝗲𝗰𝘂𝗿𝗶𝘁𝘆
I use a protect middleware to guard routes. It checks the JWT in the Authorization header.
I use optional chaining when reading headers. This prevents the app from crashing if a header is missing.
For this project, I use a 7-day access token. While production apps use short-lived tokens and refresh tokens, a long-lived token works well for this specific scope.
𝗗𝗮𝘁𝗮 𝗜𝗻𝘁𝗲𝗴𝗿𝗶𝘁𝘆 𝘄𝗶𝘁𝗵 𝗧𝗿𝗮𝗻𝘀𝗮𝗰𝘁𝗶𝗼𝗻𝘀
Creating a project requires three steps:
- Create the project record
- Assign the owner
- Create the default boards
If one step fails, your data becomes corrupt. I use prisma.$transaction to wrap these steps. If any part fails, the whole process rolls back. This keeps your database clean.
Common Logic Errors
I ran into two common bugs:
Relation Arrays: When you include relations in a query, Prisma returns an array. You cannot access a property directly on the relation. You must pick the first item in the array first.
रूट ऑर्डर: Express ऊपर से नीचे की ओर रूट को मैच करता है। यदि आप किसी विशिष्ट रूट (specific route) से पहले पैरामीटर वाला रूट रखते हैं, तो Express गलत रूट को मैच कर लेगा। हमेशा पैरामीटराइज्ड रूट से ऊपर विशिष्ट रूट रखें।
ये बैकएंड पैटर्न अब मेरे वर्कफ़्लो का हिस्सा हैं।