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Node.Js MongoParseError URI malformed, cannot be parsed

When I run it on my local computer I don't get any problem, I encounter this error when I deploy it to Heroku. I don't fully understand the reason.
MongoParseError URI malformed, cannot be parsed
I just get this on Heroku. Also, my file on the server.js side is as follows.
const dotenv = require("dotenv");
dotenv.config({ path: "./.env" });
const app = require("./app");
const DB = process.env.DATABASE.replace(
"<PASSWORD>",
process.env.DATABASE_PASSWORD
);
console.log(DB);
mongoose
.connect(DB, {
auth: {
user: process.env.MONGO_DB_USER,
password: process.env.MONGO_DB_PASSWORD,
},
useNewUrlParser: true,
useCreateIndex: true,
useFindAndModify: false,
})
.then(() => console.log("DB connection successful!"));
"mongoose": "^5.13.14", "mongoose-intl": "^3.3.0", "dotenv":
"^16.0.3",
My .env file has MongoDB URLs and passwords. That's why I don't share. Works great locally too. but there are problems in deployment.

I had the same issue and it was caused by the fact that on heroku the node version was updated to 19.0.0.
To find out which version of node is being used on heroku, run heroku run 'node -e "console.log(process.versions)"'
The error is caused by mongoose version, maybe you are using an old one.
To solve this, try to update to mongoose 6.7.2 and you should be fine.

If you sure your environment variables are same, it may be related to ip.
Try adding 0.0.0.0/0 IP address in Atlas Network Access. If you already have this IP, then delete and add it again. After that restart all dynos in Heroku. (inside dropdown menu at top right)

check your server dotenv value.
In a cloud environment the .env file may be different.
can you check local process.env and Heroku's process.env?

It seems that there is an error in your mongoDB URI
For now i don't know what your URI is which is .env file but i can suggest you a few things
1- Firstly you need to replace the first two lines of your code with this one
require('dotenv').config();
2- In your .env file you need to create a variable named
MONGODB_URI=mongodb+srv://[username:password#]host[/[database][?options]]
whatever your password and username is just fill in that here in URI
Finally you need to change the connection string and your file should look like this
require('dotenv').config();
const app = require("./app");
mongoose
.connect(process.env.MONGODB_URI)
.then(() => {
console.log("Connection Successfull");
})
.catch((error) => {
console.log("Connection Unsuccessfull");
});

How to move from Firebase Functions to Cloud Run after encountering 540s timeout limit?

I was reading this Reddit thread where a user mentioned that 540s is the limit of Firebase Functions and that moving to Cloud Run was recommended.
As others have said 540s is the maximum timeout and if you want to increase it without changing much else about your code, consider moving to Cloud Run. ​- #samtstern on Reddit
After looking at the Node.JS QuickStart documentation
and other content on YouTube and Google, I did not find a good guide explaining how to move your Firebase Function to Cloud Run.
One of the issues that were not addressed by what I read, for example: what do I replace the firebase-functions package with to define the function? Etc...
So, how may I move my Firebase Function over to Cloud Run to not run into the 540s max timeout limitation ?
​const functions = require('firebase-functions');
​const runtimeOpts = {timeoutSeconds: 540,memory: '2GB'}
​exports.hourlyData = functions.runWith(runtimeOpts).pubsub.schedule('every 1 hours')

Preface: The following steps have been generalized for a wider audience than just the OP's problem (covers HTTP Event, Scheduled and Pub/Sub Functions) and have been adapted from the documentation linked in the question: Deploying Node.JS Images on Cloud Run.
Step 0: Code/Architecture Review
More often than not, exceeding the 9-minute timeout of a Cloud Function is a result of a bug in your code - make sure to evaluate this before switching to Cloud Run as this will just make the problem worse. The most common of these is sequential instead of parallelized asynchronous processing (normally caused by using await in a for/while loop).
If your code is doing meaningful work that is taking a long time, consider sharding it out to "subfunctions" that can all work on the input data in parallel. Instead of processing data for every user in your database, you can use a single function to trigger multiple instances of a function that each that take care of different user ID ranges such as a-l\uf8ff, m-z\uf8ff, A-L\uf8ff, M-Z\uf8ff and 0-9\uf8ff.
Lastly, Cloud Run and Cloud Functions are quite similar, they are designed to take a request, process it and then return a response. Cloud Functions have a limit of up to 9 minutes and Cloud Runs have a limit of up to 60 minutes. Once that response has been completed (because the server ended the response, the client lost connection or the client aborted the request), the instance is severely throttled or terminated. While you can use WebSockets and gRPC for a persistent communication between server and client when using Cloud Run, they are still subject to this limitation. See the Cloud Run: General development tips documentation for more information.
Like other serverless solutions, your client and server need to be able to handle connecting to different instances. Your code shouldn't make use of local state (like a local store for session data). See the Setting request timeout documentation for more information.
Step 1: Install Google Cloud SDK
I'll refer you to the Installing Google Cloud SDK documentation for this step.
Once installed, call gcloud auth login and login with the account used for the target Firebase project.
Step 2: Get your Firebase Project settings
Open up your project settings in the Firebase Console and take note of your Project ID and your Default GCP resource location.
Firebase Functions and Cloud Run instances should be co-located with your GCP resources where possible. In Firebase Functions, this is achieved by changing the region in code and deploying using the CLI. For Cloud Run, you specify these parameters on the command line as flags (or use the Google Cloud Console). For the below instructions and for simplicity, I will be using us-central1 as my Default GCP resources location is nam5 (us-central).
If using the Firebase Realtime Database in your project, visit your RTDB settings in the Firebase Console and take note of your Database URL. This is usually of the form https://PROJECT_ID.firebaseio.com/.
If using Firebase Storage in your project, visit your Cloud Storage settings in the Firebase Console and take note of your Bucket URI. From this URI, we need to take note of the host (ignore the gs:// part) which is usually of the form PROJECT_ID.appspot.com.
Here's a table that you can copy to help keep track:
Project ID:
PROJECT_ID
Database URL:
https://PROJECT_ID.firebaseio.com
Storage Bucket:
PROJECT_ID.appspot.com
Default GCP Resource Location:
Chosen Cloud Run Region:
Step 3: Create Directories
In your Firebase Project directory or a directory of your choosing, create a new cloudrun folder.
Unlike Firebase Cloud Functions, where you can define multiple functions in a single module of code, each Cloud Run image uses its own module of code. For this reason, each Cloud Run image should be stored in its own directory.
As we are going to define a Cloud Run instance called helloworld, we'll create a directory called helloworld inside cloudrun.
mkdir cloudrun
mkdir cloudrun/helloworld
cd cloudrun/helloworld
Step 4: Create package.json
For correct deployment of the Cloud Run image, we need to provide a package.json that is used to install dependencies in the deployed container.
The format of the package.json file resembles:
{
"name": "SERVICE_NAME",
"description": "",
"version": "1.0.0",
"private": true,
"main": "index.js",
"scripts": {
"start": "node index.js"
"image": "gcloud builds submit --tag gcr.io/PROJECT_ID/SERVICE_NAME --project PROJECT_ID",
"deploy:public": "gcloud run deploy SERVICE_NAME --image gcr.io/PROJECT_ID/SERVICE_NAME --allow-unauthenticated --region REGION_ID --project PROJECT_ID",
"deploy:private": "gcloud run deploy SERVICE_NAME --image gcr.io/PROJECT_ID/SERVICE_NAME --no-allow-unauthenticated --region REGION_ID --project PROJECT_ID",
"describe": "gcloud run services describe SERVICE_NAME --region REGION_ID --project PROJECT_ID --platform managed",
"find": "gcloud run services describe SERVICE_NAME --region REGION_ID --project PROJECT_ID --platform managed --format='value(status.url)'"
},
"engines": {
"node": ">= 12.0.0"
},
"author": "You",
"license": "Apache-2.0",
"dependencies": {
"express": "^4.17.1",
"body-parser": "^1.19.0",
/* ... */
},
"devDependencies": {
/* ... */
}
}
In the above file, SERVICE_NAME, REGION_ID and PROJECT_ID are to be swapped out as appropriate with the details from step 2. We also install express and body-parser to handle the incoming request.
There are also a handful of module scripts to help with deployment.
Script Name
Description
image
Submits the image to Cloud Build to be added to the Container Registry for other commands.
deploy:public
Deploys the image from the above command to be used by Cloud Run (while allowing any requester to invoke it) and returns its service URL (which is partly randomized).
deploy:private
Deploys the image from the above command to be used by Cloud Run (while requiring that the requester that invokes it is an authorized user/service account) and returns its service URL (which is partly randomized).
describe
Gets the statistics & configuration of the deployed Cloud Run.
find
Extracts only the service URL from the response of npm run describe
Note: Here, "Authorized User" refers to a Google Account associated with the project, not an ordinary Firebase User. To allow a Firebase User to invoke your Cloud Run, you must deploy it using deploy:public and handle token validation in your Cloud Run's code, rejecting requests appropriately.
As an example of this file filled in, you get this:
{
"name": "helloworld",
"description": "Simple hello world sample in Node with Firebase",
"version": "1.0.0",
"private": true,
"main": "index.js",
"scripts": {
"start": "node index.js"
"image": "gcloud builds submit --tag gcr.io/com-example-cloudrun/helloworld --project com-example-cloudrun",
"deploy:public": "gcloud run deploy helloworld --image gcr.io/com-example-cloudrun/helloworld --allow-unauthenticated --region us-central1 --project com-example-cloudrun",
"deploy:public": "gcloud run deploy helloworld --image gcr.io/com-example-cloudrun/helloworld --no-allow-unauthenticated --region us-central1 --project com-example-cloudrun",
"describe": "gcloud run services describe helloworld --region us-central1 --project com-example-cloudrun --platform managed",
"find": "gcloud run services describe helloworld --region us-central1 --project com-example-cloudrun --platform managed --format='value(status.url)'"
},
"engines": {
"node": ">= 12.0.0"
},
"author": "You",
"license": "Apache-2.0",
"dependencies": {
/* ... */
},
"devDependencies": {
/* ... */
}
}
Step 5: Create your container files
To tell Cloud Build what container to use for your Cloud Run image, you must create a Dockerfile for your image. To prevent sending the wrong files to the server, you should also specify a .dockerignore file.
In this file, we use the Firebase Project settings from Step 2 to recreate the process.env.FIREBASE_CONFIG environment variable. This variable is used by the Firebase Admin SDK and contains the following information as a JSON string:
{
databaseURL: "https://PROJECT_ID.firebaseio.com",
storageBucket: "PROJECT_ID.appspot.com",
projectId: "PROJECT_ID"
}
Here is cloudrun/helloworld/Dockerfile:
# Use the official lightweight Node.js 14 image.
# https://hub.docker.com/_/node
FROM node:14-slim
# Create and change to the app directory.
WORKDIR /usr/src/app
# Copy application dependency manifests to the container image.
# A wildcard is used to ensure copying both package.json AND package-lock.json (when available).
# Copying this first prevents re-running npm install on every code change.
COPY package*.json ./
# Install production dependencies.
# If you add a package-lock.json, speed your build by switching to 'npm ci'.
# RUN npm ci --only=production
RUN npm install --only=production
# Copy local code to the container image.
COPY . ./
# Define default configuration for Admin SDK
# databaseURL is usually "https://PROJECT_ID.firebaseio.com", but may be different.
# TODO: Update me
ENV FIREBASE_CONFIG={"databaseURL":"https://PROJECT_ID.firebaseio.com","storageBucket":"PROJECT_ID.appspot.com","projectId":"PROJECT_ID"}
# Run the web service on container startup.
CMD [ "node", "index.js" ]
Here is cloudrun/helloworld/.dockerignore:
Dockerfile
.dockerignore
node_modules
npm-debug.log
Step 6: Create & deploy your entry point
When a new Cloud Run instance is launched, it will normally specify the port it wants your code to listen on using the PORT environment variable.
Variant: Migrating a HTTP Event Function
When you use a HTTP Event function from the firebase-functions package, it internally handles body-parsing on your behalf. The Functions Framework uses the body-parser package for this and defines the parsers here.
To handle user authorization, you could use this validateFirebaseIdToken() middleware to check the ID token given with the request.
For a HTTP-based Cloud Run, configuring CORS will be required to invoke it from a browser. This can be done by installing the cors package and configuring it appropriately. In the below sample, cors will reflect the origin sent to it.
const express = require('express');
const cors = require('cors')({origin: true});
const app = express();
app.use(cors);
// To replicate a Cloud Function's body parsing, refer to
// https://github.com/GoogleCloudPlatform/functions-framework-nodejs/blob/d894b490dda7c5fd4690cac884fd9e41a08b6668/src/server.ts#L47-L95
// app.use(/* body parsers */);
app.enable('trust proxy'); // To respect X-Forwarded-For header. (Cloud Run is behind a load balancer proxy)
app.disable('x-powered-by'); // Disables the 'x-powered-by' header added by express (best practice)
// Start of your handlers
app.get('/', (req, res) => {
const name = process.env.NAME || 'World';
res.send(`Hello ${name}!`);
});
// End of your handlers
const port = process.env.PORT || 8080;
app.listen(port, () => {
console.log(`helloworld: listening on port ${port}`);
});
In the $FIREBASE_PROJECT_DIR/cloudrun/helloworld directory, execute the following commands to deploy your image:
npm run image // builds container & stores to container repository
npm run deploy:public // deploys container image to Cloud Run
Variant: Invoke using Cloud Scheduler
When invoking a Cloud Run using the Cloud Scheduler, you can choose which method is used to invoke it (GET, POST (the default), PUT, HEAD, DELETE). To replicate a Cloud Function's data and context parameters, it is best to use POST as these will then be passed in the body of the request. Like Firebase Functions, these requests from Cloud Scheduler may be retried so make sure to handle idempotency appropriately.
Note: Even though the body of a Cloud Scheduler invocation request is JSON-formatted, the request is served with Content-Type: text/plain, which we need to handle.
This code has been adapted from the Functions Framework source (Google LLC, Apache 2.0)
const express = require('express');
const { json } = require('body-parser');
async function handler(data, context) {
/* your logic here */
const name = process.env.NAME || 'World';
console.log(`Hello ${name}!`);
}
const app = express();
// Cloud Scheduler requests contain JSON using
"Content-Type: text/plain"
app.use(json({ type: '*/*' }));
app.enable('trust proxy'); // To respect X-Forwarded-For header. (Cloud Run is behind a load balancer proxy)
app.disable('x-powered-by'); // Disables the 'x-powered-by' header added by express (best practice)
app.post('/*', (req, res) => {
const event = req.body;
let data = event.data;
let context = event.context;
if (context === undefined) {
// Support legacy events and CloudEvents in structured content mode, with
// context properties represented as event top-level properties.
// Context is everything but data.
context = event;
// Clear the property before removing field so the data object
// is not deleted.
context.data = undefined;
delete context.data;
}
Promise.resolve()
.then(() => handler(data, context))
.then(
() => {
// finished without error
// the return value of `handler` is ignored because
// this isn't a callable function
res.sendStatus(204); // No content
},
(err) => {
// handler threw error
console.error(err.stack);
res.set('X-Google-Status', 'error');
// Send back the error's message (as calls to this endpoint
// are authenticated project users/service accounts)
res.send(err.message);
}
)
});
const port = process.env.PORT || 8080;
app.listen(port, () => {
console.log(`helloworld: listening on port ${port}`);
});
Note: The Functions Framework handles errors by sending back a HTTP 200 OK response with a X-Google-Status: error header. This effectively means "failed successfully". As an outsider, I'm not sure why this is done but I can assume it's so that the invoker knows to not bother retrying the function - it'll just get the same result.
In the $FIREBASE_PROJECT_DIR/cloudrun/helloworld directory, execute the following commands to deploy your image:
npm run image // builds container & stores to container repository
npm run deploy:private // deploys container image to Cloud Run
Note: In the following setup commands (only need to run these once), PROJECT_ID, SERVICE_NAME, SERVICE_URL and IAM_ACCOUNT will need to be substituted as appropriate.
Next we need to create a service account that Cloud Scheduler can use to invoke the Cloud Run. You can call it whatever you want such as scheduled-run-invoker. The email of this service account will be referred to as IAM_ACCOUNT in the next step. This Google Cloud Tech YouTube video (starts at the right spot, about 15s) will quickly show what you need to do. Once you've created the account, you can create the Cloud Scheduler job following the next 30 or so seconds of the video or use the following command:
gcloud scheduler jobs create http scheduled-run-SERVICE_NAME /
--schedule="every 1 hours" /
--uri SERVICE_URL /
--attempt-deadline 60m /
--http-method post /
--message-body='{"optional-custom-data":"here","if-you":"want"}' /
--oidc-service-account-email IAM_ACCOUNT
--project PROJECT_ID
Your Cloud Run should now be scheduled.
Variant: Invoke using Pub/Sub
To my understanding, the deploy process is the same as for a scheduled run (deploy:private) but I'm unsure about the specifics. However, here is the Cloud Run source for a Pub/Sub parser:
This code has been adapted from the Functions Framework source (Google LLC, Apache 2.0)
const express = require('express');
const { json } = require('body-parser');
const PUBSUB_EVENT_TYPE = 'google.pubsub.topic.publish';
const PUBSUB_MESSAGE_TYPE =
'type.googleapis.com/google.pubsub.v1.PubsubMessage';
const PUBSUB_SERVICE = 'pubsub.googleapis.com';
/**
* Extract the Pub/Sub topic name from the HTTP request path.
* #param path the URL path of the http request
* #returns the Pub/Sub topic name if the path matches the expected format,
* null otherwise
*/
const extractPubSubTopic = (path: string): string | null => {
const parsedTopic = path.match(/projects\/[^/?]+\/topics\/[^/?]+/);
if (parsedTopic) {
return parsedTopic[0];
}
console.warn('Failed to extract the topic name from the URL path.');
console.warn(
"Configure your subscription's push endpoint to use the following path: ",
'projects/PROJECT_NAME/topics/TOPIC_NAME'
);
return null;
};
async function handler(message, context) {
/* your logic here */
const name = message.json.name || message.json || 'World';
console.log(`Hello ${name}!`);
}
const app = express();
// Cloud Scheduler requests contain JSON using
"Content-Type: text/plain"
app.use(json({ type: '*/*' }));
app.enable('trust proxy'); // To respect X-Forwarded-For header. (Cloud Run is behind a load balancer proxy)
app.disable('x-powered-by'); // Disables the 'x-powered-by' header added by express (best practice)
app.post('/*', (req, res) => {
const body = req.body;
if (!body) {
res.status(400).send('no Pub/Sub message received');
return;
}
if (typeof body !== "object" || body.message === undefined) {
res.status(400).send('invalid Pub/Sub message format');
return;
}
const context = {
eventId: body.message.messageId,
timestamp: body.message.publishTime || new Date().toISOString(),
eventType: PUBSUB_EVENT_TYPE,
resource: {
service: PUBSUB_SERVICE,
type: PUBSUB_MESSAGE_TYPE,
name: extractPubSubTopic(req.path),
},
};
// for storing parsed form of body.message.data
let _jsonData = undefined;
const data = {
'#type': PUBSUB_MESSAGE_TYPE,
data: body.message.data,
attributes: body.message.attributes || {},
get json() {
if (_jsonData === undefined) {
const decodedString = Buffer.from(base64encoded, 'base64')
.toString('utf8');
try {
_jsonData = JSON.parse(decodedString);
} catch (parseError) {
// fallback to raw string
_jsonData = decodedString;
}
}
return _jsonData;
}
};
Promise.resolve()
.then(() => handler(data, context))
.then(
() => {
// finished without error
// the return value of `handler` is ignored because
// this isn't a callable function
res.sendStatus(204); // No content
},
(err) => {
// handler threw error
console.error(err.stack);
res.set('X-Google-Status', 'error');
// Send back the error's message (as calls to this endpoint
// are authenticated project users/service accounts)
res.send(err.message);
}
)
});
const port = process.env.PORT || 8080;
app.listen(port, () => {
console.log(`helloworld: listening on port ${port}`);
});

Make Node server.js file safer by removing security information

I have a public git[hub] project, and am now ready to switch it from development to production. We are in the research field, so we like to share our code too!
I have a server.js file that we start with node server.js like most tutorials.
In it, there is connection information for the SQL server, and the location of the HTTPS certificates. It looks something like this:
var https = require('https');
var express = require('express');
var ... = require('...');
var fs = require('fs');
var app = express();
var Sequelize = require('sequelize'),
// ('database', 'username', 'password');
sequelize = new Sequelize('db', 'uname', 'pwd', {
logging: function () {},
dialect: 'mysql',
…
});
…
var secureServer = https.createServer({
key: fs.readFileSync('./location/to/server.key'),
cert: fs.readFileSync('./location/to/server.crt'),
ca: fs.readFileSync('./location/to/ca.crt'),
requestCert: true,
rejectUnauthorized: false
}, app).listen('8443', function() {
var port = secureServer.address().port;
console.log('Secure Express server listening at localhost:%s', port);
});
In PHP you can have the connection information in another file, then import the files (and therefore variables) into scope to use. Is this possible for the SQL connection (db, uname, pwd) and the file locations of the certs (just to be safe) so that we can commit the server.js file to git and ignore/not follow the secret file?

You can do this in a lot of different ways. One would be to use environment variables like MYSQL_USER=foo MYSQL_PASSWD=bar node server.js and then use process.env.MYSQL_USER in the code.
You can also read from files as you have suggested. You can do require("config.json") and node will automatically parse and import the JSON as JavaScript constructs. You can then .gitignore config.json and perhaps provide an example.config.json.
If you want to support both of these at once there is at least one library that allows you to do this simply: nconf.

You can always just store the configuration information in a JSON file. Node natively supports JSON files. You can simply require it:
var conf = require('myconfig.json');
var key = fs.readFileSync(conf.ssl_keyfile);
There are also 3rd party libraries for managing JSON config files that add various features. I personally like config.json because it allows you to publish a sample config file with empty values then, without modifying the sample config file, you can override those values using a .local.json file. It makes it easier to deal with config files in repos and also makes it easier to publish changes to the config file.

Here is great writeup about how you should organise your deployments
Basically all application critical variables like db password, secret keys, etc., should be accessible via environment variables.
You could do something like this
// config.js
const _ = require('lodash');
const env = process.env.NODE_ENV || 'development';
const config = {
default: {
mysql: {
poolSize: 5,
},
},
development: {
mysql: {
url: 'mysql://localhost/database',
},
},
production: {
mysql: {
url: process.env.DB_URI,
},
},
};
module.exports = _.default(config.default, config[env]);
// app.js
const config = require('./config');
// ....
const sequelize = new Sequelize(config.mysql.url);
Code is not perfect, but should be enough to get the idea.

Sails.js -- Accessing local.js environment settings in controllers

In production I have AWS credentials stored as heroku config variables.
In development I want to include the config details in config/local.js, but how do I access the config details in a controller?
local.js contains:
module.exports = {
aws_key: "...", aws_secret: "..."
}
In my controller I have tried aws_key, config.aws_key, and others - but no luck. Is there a main app namespace that I can use to scope into the properties exported by local.js?
I am new to sails and I feel like this should be straight forward - any help would be appreciated.

Solution found. Step 3 was where I was having trouble.
tl;dr
What I didn't realize was that the module.exports.thing makes the thing object available through sails.config.thing. Good to know.
1) I created a new file at config/aws.js with the contents
// Get heroku config values
module.exports.aws = {
key: process.env.AWS_KEY,
secret: process.env.AWS_SECRET
}
2) In local.js put the actual AWS creds (this won't end up in the repository since sails automatically ignores local.js using gitignore).
aws: {
key: actual-key,
secret: actual-secret
}
This allows for local testing where we don't have access to the heroku config settings, while protecting these values from being exposed in a github repo.
3) Now, to access in the controller:
var aws_config = sails.config.aws;
AWS.config.update({
accessKeyId: aws_config.key,
secretAccessKey: aws_config.secret
});

Appfog with node.js how to access with javascript to mysql databases?

I have one node.js application published in appfog, but when I try to access a mysql database through javascript
with ( https://github.com/felixge/node-mysql ), "node-mysql" seems that is not installed, what is the way to do this?
there is no documentation on appfog site. thanks.
the code of server app.js:
if(process.env.VCAP_SERVICES){
var env = JSON.parse(process.env.VCAP_SERVICES);
var cre = env['mysql-5.1'][0]['credentials'];
}
var Client = require('mysql').Client,
client = new Client();
client.user = cre.user;
client.password = cre.password;
client.host=cre.host;
client.port=cre.port;
client.database=cre.name;
client.connect();
client.query(
'SELECT * FROM scores ',
function selectPlayers(err, results, fields) {
if (err) {
console.log("Error: " + err.message);
throw err;
}
console.log("Number of rows: "+results.length);
console.log(results);
client.end();
});
and the error:
module.js:340
throw err;
^
Error: Cannot find module 'mysql'
at Function.Module._resolveFilename (module.js:338:15)

you should add
"mysql": "2.0.x || 2.1.x",
to the dependencies in your package.json file, and then do
npm install
You can check out Appfog's documentation here. There is a section about dependency management

Appfog have support for NPM, the standard way to install dependencies in node.
You can either do it through the console with npm install mysql or by adding mysql to your package.json file and do npm install.
The second way will automatically install all the dependencies for your app.
Source: https://docs.appfog.com/languages/node#node-dep-mgmt

Hi you just need to download and install node.js locally this will enable npm command on your machine after that go to "Services" section on your AppFog panel create you mySQL service (VCAP_SERVICES)
When you provision and bind a service to your app, AppFog creates an environment variable called VCAP_SERVICES.
This variable contains a JSON document with a list of all credentials and connection information for the bound services.
Here's an example that of the environment variable for an app that has two MySQL database services bound to it:
{"mysql-5.1":[
{
"name":"mysql-4f700",
"label":"mysql-5.1",
"plan":"free",
"tags":["mysql","mysql-5.1","relational"],
"credentials":{
"name":"d6d665aa69817406d8901cd145e05e3c6",
"hostname":"mysql-node01.us-east-1.aws.af.cm",
"host":"mysql-node01.us-east-1.aws.af.cm",
"port":3306,
"user":"uB7CoL4Hxv9Ny",
"username":"uB7CoL4Hxv9Ny",
"password":"pzAx0iaOp2yKB"
}
},
{
"name":"mysql-f1a13",
"label":"mysql-5.1",
"plan":"free",
"tags":["mysql","mysql-5.1","relational"],
"credentials":{
"name":"db777ab9da32047d99dd6cdae3aafebda",
"hostname":"mysql-node01.us-east-1.aws.af.cm",
"host":"mysql-node01.us-east-1.aws.af.cm",
"port":3306,
"user":"uJHApvZF6JBqT",
"username":"uJHApvZF6JBqT",
"password":"p146KmfkqGYmi"
}
}
]}
You can use your app's language-specific facility to call the environment variable.
In Java:
java.lang.System.getenv("VCAP_SERVICES")
In Ruby:
ENV['VCAP_SERVICES']
In Javascript:
process.env.VCAP_SERVICES
In Python:
os.getenv("VCAP_SERVICES")
In PHP:
getenv("VCAP_SERVICES")