The Pit Stop Challenge

Lab Configuration

Focus: Embedded Arrays, Data Populations, Relational Design

In this lab section, you will be expanding your current Express application using the architecture methods learned in Chapter 8.

Choose the track that fits your current confidence level:

• Maintenance: Connect relationships on paper and implement a basic .populate() pipeline.
• Custom Job: Implement a new embedded array of subdocuments for project milestones with full CRUD.
• Solo’s Garage: Refactor your project architecture to handle bidirectionally referencing data, mapping projects to clients and clients back to projects.

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Maintenance Track

Goal: Modify your existing project data to include a hard-coded Array of Tags, and implement populate() to load a separate Author collection onto the main page.

Step-by-Step:

1. Update your schema to include tags: [{ type: String }]. Update existing entries manually via MongoDB Atlas to include sample tags.
2. Render those tags via a comma-separated join within your EJS Detail view.
3. Build an Author model. Create two entries via Atlas.
4. Update your main schema to track authorId. Map the IDs inside Atlas.
5. In your router, run .populate('authorId') and verify the author name logs.

T.A. Watts

Student-to-AI Prompt for the Maintenance Track:

“Review my attached schemas. I’ve added an authorId referencing an Author collection, and an array for tags. I also attached my router. Please check how I am utilizing .populate('authorId')—is this the correct implementation to expose authorId.name in my EJS?”

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Custom Job Track

Goal: Fully implement an embedded array of subdocuments to track “Milestones” for each project (e.g., Phase 1, Phase 2, Launch), bypassing simple strings for complex nested objects.

Step-by-Step:

1. Establish milestoneSchema on your main model with title, date, and isCompleted fields.
2. Embed this schema into your Project model as an array: milestones: [milestoneSchema].
3. Create a new form panel on your project admin view to add a new Milestone.
4. Hook your admin router to capture the milestone form data and push() it into the project’s embedded array and save().
5. Use an EJS loop to display all tracked milestones and their completion status tightly coupled to the project screen.

T.A. Watts

Student-to-AI Prompt for the Custom Job:

“Review my attached Project schema and admin form for adding Milestones. I am attempting to create an embedded array of subdocuments. Please verify if my data is passing cleanly into my Mongoose save function and if my subdocument structure is valid.”

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Solo’s Garage Track

Goal: Build an advanced double-referenced relationship. Allow a Client to have many Projects, while a Project belongs to a single Client.

Step-by-Step:

1. Create a distinct Client model collection (name, industry, projects: [{ type: ObjectId, ref: 'Project' }]).
2. Give the Project model a clientId: { type: ObjectId, ref: 'Client' }.
3. When saving a new Project and assigning it a Client from a dropdown, you must not only save the Project, but run a query to find the assigned Client and push the new Project’s ID into the Client’s projects array.
4. Write a script to handle what happens when a Project is deleted. It must be cleanly removed from the Client’s array to prevent orphaned references.

Professor Solo

Student-to-AI Prompt for Solo’s Garage:

“Review my route handler for managing two-way data references between Projects and Clients. I am attempting to update both collections when a new project is created or assigned. Can you provide feedback on the efficiency of my logic, and ensure I haven’t created a scenario for orphaned data?”