# M2 - Heroku Deployment (with Mongo Atlas)
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### 1. [Signup for a Free MongoDB Atlas account](https://www.mongodb.com/cloud/atlas/lp/try2)
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### 2. [Sign Up & Create a Free Cluster](https://docs.atlas.mongodb.com/tutorial/deploy-free-tier-cluster/)
1. Sign Up for Mongo Atlas - enter the email, password, first name, last name
2. Select >>> **Starter Clusters (or Shared Clusters)**
3. In the drop-down **Cloud Provider & Region** select:
- Europe Region
4. in the **Cluster Tier** select:
5. In the drop-down "**Cluster Tier**" make sure to select:
- **M0 Sandbox** - with the flag **Free forever**.
6. Click the button **Create Cluster**
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## 3. Setup MongoDB Atlas Cluster:
1. In the sidebar in the **SECURITY** part:
- select **-> Database Access**
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2. Click on **<u>+ ADD NEW USER</u>** to create a new user
- Select **Read and write to any database** - User Privileges
- Set the **Username** and **Password**
- Set **Database User Privileges** to : ***Atlas admin***
- Create New User
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3. In the sidebar select **SECURITY -> Network Access**
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4. Click on **<u>+ ADD IP ADDRESS</u>**
- Click on **ALLOW ACCESS FROM ANYWHERE**
- Confirm
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5. Connect To Your Cluster: Click on the gray button **CONNECT**
- Select **Connect Your Application** option
- Choose Your driver version: **DRIVER**: Node.js
- **Copy** the **Connection String Only**
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6. Update the connection string and add the ***username*** and ***password***.
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## 4. Create a Heroku account
https://signup.heroku.com/
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## 5. Install Heroku CLI
#### [LINK: Docs - Install the Heroku CLI](https://devcenter.heroku.com/articles/heroku-cli#npm)
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## 6. Login to the Heroku website and *<u>Create New App</u>*
#### Open your [Heroku Dashboard](https://dashboard.heroku.com/apps)
1. Go to [`dashboard.heroku.com/apps`](https://dashboard.heroku.com/apps), and then select:
**New** >>> **Create new app** >>> **Choose region - Europe** >>> **Create app**.
2. After you create the app, you should be redirected to the app's dashboard.
3. Select the **Deploy** section.
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## 7. Connect Heroku app to the local repository
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### Follow the Deployment instructions - *Deploy* section
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While in the Heroku app *Dashboard* open the ***Deploy*** section
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To login to Heroku and create a new Dyno, from your server/project root directory, run the following commands (also mentioned in the ***Deploy*** section) :
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> <sub>In the below example the angle brackets `< >` indicate the identifier/parameter/argument values that are provided by the user. You should omit them when executing the commands.</sub>
```bash
# Login to heroku from the terminal
heroku login
```
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```bash
# Add heroku remote
heroku git:remote -a <name-of-the-newly-created-app>
# Check the remotes available
# Newly added `heroku` remote repository connection should be shown
git remote -v
```
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```bash
# Commit the most recent work on the development branch
git add .
git commit -m 'Write a clear meaningful commit message here'
git push origin <development-branch-name>
# Checkout to the master branch
git checkout master
# Merge (bring) updates from the development branch
git merge <development-branch-name>
git push heroku master
```
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## 8. Set *Config Vars* in Heroku
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1. In the Heroku **app** **Dashboard** go to >> **Settings**:
2. Click on the **Reveal Config Vars**
3. Create the new keys for the environment variables:
- `SESSION_SECRET`
- `MONGODB_URI` - Set the value to be the previously copied **Connection String** from Mongo Atlas. **Remember to add the** `username` and `password` **to the Connection String** you created in Mongo Atlas.
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For the sessions secret:
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```bash
SESSION_SECRET=s0m3RaNd0mS7r1nG123
```
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For the newly created MongoDB database in the Atlas Cloud.
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> <sub>In the below example the angle brackets `< >` indicate the identifier/parameter/argument values that are provided by the user. You should omit them when executing the commands.</sub>
```bash
MONGODB_URI=<Mongo Atlas Conection String with username and password>
```
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:heavy_exclamation_mark: Double-check that all needed config variables (`MONGODB_URI`, `SESSION_SECRET`, etc.) were added properly during the previous step :
*Heroku app **Dashboard** **>>** **Settings** **>>** **Config Vars** **>>** **Reveal Config Vars***
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## 9. Update the project files
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1. Check that `mongoose.connect` URLs in the `app.js` and `bin/seed.js` (if you are using a seed) are updated and using `process.env.MONGODB_URI`.
#### `app.js` & `bin/seed.js`
```js
require('dotenv').config(); // <--- ADD
// ...
// ...
mongoose
.connect(
process.env.MONGODB_URI, // <--- UPDATE
{useNewUrlParser: true}
)
.then((x) => console.log('Connected to the DB')
.catch(err => console.error('Error while connecting to DB', err));
// ...
```
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2. Update the `package.json` and [specify the version of Node](https://devcenter.heroku.com/articles/deploying-nodejs#specify-the-version-of-node):
- Run command `node --version` to get the version of Node.js installed:
```bash
node --version
#> v12.4.1
```
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- Add the `engines` config section with the `node` version to the `package.json`.
For example, if your node version was `v.12.4.1` you should set the following:
##### `package.json`
```json
"engines": {
"node": "12.x"
}
```
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3. After updating the `mongoose.connect` connection strings and adding the `node` version make sure to `commit` the changes and push to remote on GitHub (`origin`) and Heroku (`heroku`)
```bash
git add .
git commit -m 'Update mongoose connection and add node version'
# Push the commit and update the version on GitHub
git push origin master
# Push the commit and update the deployed version on Heroku
git push heroku master
# Open the app in the browser (from terminal)
heroku open
```
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## 10. Heroku commands
### Logs
To fetch your app’s most recent logs, use the `heroku logs` command:
```bash
heroku logs
```
The `logs` command retrieves 100 log lines by default.
You can specify the number of log lines to retrieve (up to a maximum of 1,500 lines) by using the `--num` (or `-n`) option.
```bash
heroku logs -n 200
```
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### [Troubleshooting - Real-time tail](https://devcenter.heroku.com/articles/logging#real-time-tail)
If there was an error during the deployment, you will be shown the following screen prompting you to run `heroku logs --tail` command:
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Real-time tail displays recent logs and leaves the session open for real-time logs to stream in.
This command is used to troubleshoot any deployment errors when the deployed app is not working as expected.
```bash
heroku logs --tail
```
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### Access the terminal of the Heroku container
We can open the terminal instance on the Heroku container ([dyno](https://www.heroku.com/dynos)) in order to run custom scripts or see the files included in the instance. To do this we use the command [`heroku run bash`](https://devcenter.heroku.com/articles/heroku-cli-commands#heroku-run).
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For example to **run the seed sequence and populate the production database** we should do the following :
```bash
# Open the terminal in the app dyno in Heroku
heroku run bash
# We may then run the seed file
node bin/seed.js
```
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