Netlify lambda function timing out after 10 seconds - netlify

Question

I am having trouble returning data from my Netlify serverless function in my production environment. It currently is timing out after 10 seconds, responding with a status code of 502 and the following error message:
{
"errorMessage": "2019-... 5f... Task timed out after 10.01 seconds"
}
However, in my development environment, the Netlify serverless function works perfectly, responding with the data from my database.
I have confirmed that the environment variables on my Netlify site and in my .env file are the same. How would I go about debugging this problem and solving the issue?
Netlify serverless function
const { connectDatabase, ProjectSchema } = require('../database')
const createHeaders = origin => {
// This is a comma-separated list of allowed origins, including my local
// environment and production website
const allowedOrigins = process.env.ALLOWED_ORIGINS
? process.env.ALLOWED_ORIGINS.split(',')
: []
return {
'Content-Type': 'application/json',
'Access-Control-Allow-Headers':
'Origin, X-Requested-With, Content-Type, Accept',
'Access-Control-Allow-Origin': allowedOrigins.includes(origin)
? origin
: ''
}
}
/**
* This function queries for all `Project` instances in the database and
* returns it in the response body.
*/
const getProjects = async origin => {
try {
const projects = await ProjectSchema.find()
return {
headers: createHeaders(origin),
statusCode: 200,
body: JSON.stringify({ projects })
}
} catch (err) {
return {
headers: createHeaders(origin),
statusCode: 400,
body: JSON.stringify({ error: err })
}
}
}
/**
* This function is the serverless lambda for `/.netlify/functions/get-projects`.
*/
exports.handler = async event => {
try {
await connectDatabase()
const response = await getProjects(event.headers.origin)
return response
} catch (err) {
return err
}
}
Database functions
require('dotenv').config()
const mongoose = require('mongoose')
const { Schema } = mongoose
/**
* This function establishes a connection to the MongoDB Atlas database.
*/
exports.connectDatabase = async () => {
await mongoose.connect(process.env.DATABASE_URL, {
useNewUrlParser: true,
useUnifiedTopology: true
})
}
exports.ProjectSchema = mongoose.model(
'project',
new Schema({
title: {
type: String,
required: [true, 'Title field is required']
},
description: {
type: String,
required: [true, 'Description field is required']
}
})
)
Fetch request from client
const App = () => {
const [projects, setProjects] = useState([])
useEffect(() => {
fetch(API.GET_PROJECTS, {
headers: { 'Content-Type': 'application/json' }
})
.then(res => res.json())
.then(({ projects }) => setProjects(projects))
}, [])
return (...)
}
netlify.toml
[build]
functions = "functions"
package.json
{
"scripts": {
"build": "npm run build:client & npm run build:server",
"build:client": "webpack --config webpack.client.js",
"build:server": "netlify-lambda build src/server/functions -c webpack.server.js",
"start": "netlify-lambda serve src/server/functions",
"start:dev": "npm run build:client -- --watch"
}
}

Answer 1

This is probably a bit late to be useful, but netlify functions have a 10 second execution limit: https://docs.netlify.com/functions/overview/#default-deployment-options
They specify that if you need a longer execution time you can speak to their sales team about your use-case and they may be able to adjust it.
What is the execution time when you're running in your development environment?

Answer 2

I also had this timeout problem with Mongoose and Netlify Lambda Functions. The problem was that Mongoose keeps the database connection open, which caused the Lambda Function not to finish. My solution was to close the connection at the end of a request with mongoose.disconnect().
await mongoose.connect(process.env.DATABASE_URL, {
useNewUrlParser: true,
useUnifiedTopology: true
});
// ... do some db stuff
// make sure you close the connection when you are done
mongoose.disconnect();