Node adapter deployment in Svelte - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ component_behavior

intermediate

What happens when you run a SvelteKit app with the Node adapter?

You have built a SvelteKit app and configured it to use the Node adapter. What is the expected behavior when you run node build/index.js?

A The app runs a serverless function on a cloud platform automatically.

B The app compiles to static HTML files only, with no server running.

C The app starts a Node.js server that serves your SvelteKit pages and endpoints.

D The app fails to start because the Node adapter is not compatible with SvelteKit.

💡 Hint

Think about what the Node adapter is designed to do in SvelteKit.

The Node adapter builds your SvelteKit app into a Node.js server that you can run with node build/index.js. It serves your pages and API endpoints dynamically.

📝 Syntax

intermediate

Which configuration snippet correctly sets up the Node adapter in SvelteKit?

You want to deploy your SvelteKit app using the Node adapter. Which svelte.config.js snippet is correct?

A

import adapter from '@sveltejs/adapter-node';

export default {
  kit: {
    adapter: adapter({})
  }
};

B

import nodeAdapter from '@sveltejs/adapter-node';

export default {
  kit: {
    adapter: nodeAdapter
  }
};

C

import adapter from '@sveltejs/adapter-node';

export default {
  kit: {
    adapter: adapter
  }
};

D

import adapter from '@sveltejs/adapter-node';

export default {
  kit: {
    adapter: adapter()
  }
};

💡 Hint

The adapter function must be called to create the adapter instance.

The Node adapter is a function that you must call, optionally with options, to create the adapter instance. So adapter({}) is correct.

🔧 Debug

advanced

Why does the SvelteKit app fail to start after deploying with the Node adapter?

You deployed your SvelteKit app with the Node adapter and ran node build/index.js. The server crashes with the error: Cannot find module 'polka'. What is the most likely cause?

A You forgot to run <code>npm install</code> to install dependencies before running the build.

B The Node adapter does not support Polka, so this error is unrelated.

C The build output is missing because you did not run <code>npm run build</code> before <code>node build/index.js</code>.

D The Node adapter requires Polka to be installed manually, but it is missing.

💡 Hint

Check if the adapter requires any extra dependencies.

The Node adapter uses Polka internally, so you must have Polka installed in your project dependencies. Missing it causes this error.

❓ state_output

advanced

What is the effect of setting out option in the Node adapter configuration?

Consider this configuration snippet:

adapter({ out: 'custom_build' })

What happens when you run npm run build?

A The build files are output to the <code>custom_build</code> folder instead of the default <code>build</code> folder.

B The app will fail to build because <code>out</code> is not a valid option for the Node adapter.

C The build output folder remains <code>build</code>, but a <code>custom_build</code> folder is also created.

D The <code>out</code> option changes the server port to <code>custom_build</code>.

💡 Hint

The out option controls the output folder location.

The out option tells the Node adapter where to put the build files. Setting it to custom_build changes the output folder accordingly.

🧠 Conceptual

expert

Why choose the Node adapter over the Static adapter for deployment?

You want to deploy a SvelteKit app that has dynamic server-side logic and API endpoints. Why is the Node adapter the better choice compared to the Static adapter?

A Because the Node adapter produces smaller build sizes than the Static adapter.

B Because the Node adapter supports dynamic server-side rendering and API routes, while the Static adapter only generates static files.

C Because the Node adapter automatically deploys to serverless platforms, unlike the Static adapter.

D Because the Static adapter requires a Node.js server to run, but the Node adapter does not.

💡 Hint

Think about whether your app needs server-side code running at runtime.

The Node adapter creates a Node.js server that can run dynamic code and API endpoints. The Static adapter only generates static HTML and assets, so it cannot handle server-side logic.

Practice

1. What is the main purpose of using the @sveltejs/adapter-node in a Svelte project?

easy

A. To convert Svelte components into React components

B. To deploy the Svelte app on a Node.js server

C. To enable Svelte apps to run in the browser only

D. To add CSS styling automatically to the app

Solution

1. Step 1: Understand adapter purpose

   The @sveltejs/adapter-node is designed to prepare Svelte apps to run on Node.js servers.

2. Step 2: Compare options

   Options describing conversion to React, browser-only support, or automatic CSS styling are unrelated. Only deploying the Svelte app on a Node.js server correctly states the adapter's purpose.

3. Final Answer:

   To deploy the Svelte app on a Node.js server -> Option B

4. Quick Check:

   Node adapter = deploy on Node.js server [OK]

Hint: Node adapter = run Svelte app on Node.js server [OK]

Common Mistakes:

• Thinking adapter converts Svelte to React
• Assuming adapter only works in browsers
• Confusing adapter with styling tools

2. Which of the following is the correct way to configure the Node adapter in svelte.config.js?

easy

A. import adapter from '@sveltejs/adapter-node'; export default { kit: { adapter: adapter() } };

B. import adapter from '@sveltejs/adapter-node'; export default { kit: { adapter: adapter } };

C. import adapter from '@sveltejs/adapter-node'; export default { kit: { adapter() } };

D. import adapter from '@sveltejs/adapter-node'; export default { adapter: adapter() };

Solution

1. Step 1: Check correct adapter usage

   The Node adapter must be imported and called as a function inside the kit.adapter property.

2. Step 2: Validate syntax

   import adapter from '@sveltejs/adapter-node'; export default { kit: { adapter: adapter() } }; correctly uses adapter: adapter(). Incorrect configurations have invalid object syntax like { adapter() }, fail to call adapter as a function, or place it outside kit.

3. Final Answer:

   import adapter from '@sveltejs/adapter-node'; export default { kit: { adapter: adapter() } }; -> Option A

4. Quick Check:

   Call adapter() inside kit.adapter [OK]

Hint: Always call adapter() inside kit.adapter in svelte.config.js [OK]

Common Mistakes:

• Forgetting to call adapter as a function
• Placing adapter outside the kit object
• Using adapter without parentheses

3. Given the following commands run in a Svelte project configured with the Node adapter:

npm run build
node build/index.js

What will happen when you run node build/index.js?

medium

A. The build folder is deleted

B. An error occurs because index.js does not exist

C. The app runs in the browser automatically

D. The Svelte app starts a Node.js server serving the built app

Solution

1. Step 1: Understand build output

   Using the Node adapter, npm run build creates a Node.js server app in the build folder, including index.js.

2. Step 2: Running the server

   Running node build/index.js starts the Node.js server that serves the Svelte app.

3. Final Answer:

   The Svelte app starts a Node.js server serving the built app -> Option D

4. Quick Check:

   Build + node index.js = start server [OK]

Hint: Build creates server; node index.js starts it [OK]

Common Mistakes:

• Thinking index.js is missing after build
• Expecting app to open in browser automatically
• Confusing build folder with source code

4. You configured @sveltejs/adapter-node in svelte.config.js but running node build/index.js gives an error: Cannot find module 'devalue'. What is the likely cause?

medium

A. You forgot to install dependencies with npm install

B. You did not import the adapter correctly in svelte.config.js

C. You ran npm run dev instead of npm run build

D. The Node.js version is too old

Solution

1. Step 1: Understand the error

   The error means Node.js cannot find the devalue package, which the adapter-node server depends on.

2. Step 2: Check dependencies

   This usually happens if npm install was not run to install all required packages.

3. Final Answer:

   You forgot to install dependencies with npm install -> Option A

4. Quick Check:

   Missing module error = run npm install [OK]

Hint: Missing module? Run npm install before starting server [OK]

Common Mistakes:

• Assuming adapter import error causes missing module
• Confusing dev and build commands
• Ignoring dependency installation step

5. You want to deploy your Svelte app with the Node adapter but need to customize the server port to 4000. Which code snippet correctly sets the port when starting the server?

hard

A. In build/index.js, add const port = 4000; and pass it to the server start function

B. Modify the package.json scripts to include --port 4000

C. Set process.env.PORT = 4000 before running node build/index.js

D. Change the port in svelte.config.js inside the adapter options

Solution

1. Step 1: Understand Node adapter port config

   The Node adapter server reads the port from the environment variable PORT by default.

2. Step 2: Set environment variable before start

   Setting process.env.PORT = 4000 or running PORT=4000 node build/index.js sets the port correctly.

3. Final Answer:

   Set process.env.PORT = 4000 before running node build/index.js -> Option C

4. Quick Check:

   Port set via environment variable PORT [OK]

Hint: Set PORT env variable before starting server [OK]

Common Mistakes:

• Trying to set port in svelte.config.js (not supported)
• Modifying build/index.js directly (not recommended)
• Adding port flags in package.json scripts without env