Creating an interactive serverless application using WebSocket

In this tutorial, you will deploy an online game based on Node.js using WebSocket.

The game's static resources will be stored in a Object Storage bucket and its data, in Managed Service for YDB databases. The game data will be transferred in Data Streams streams and handled by Cloud Functions functions. For messaging between the app components, we will use a Message Queue-enabled queue. Secrets are securely delivered to the app using Yandex Lockbox. An API Gateway will accept user requests and redirect them to Cloud Functions-enabled functions.

Game user authorization is based on integration with Telegram.

To create an online game:

1. Set up your environment.
2. Create Yandex Managed Service for YDB databases.
3. Create a Yandex Data Streams-enabled data stream.
4. Create a Yandex Lockbox secret.
5. Deploy the project.
6. Create access keys for service accounts.
7. Create a new secret version and deploy your project again.
8. Create an Yandex API Gateway API gateway.
9. Connect a domain to a Telegram bot.
10. Test your application.

If you no longer need the resources you created, delete them.

Getting startedGetting started

Sign up in Yandex Cloud and create a billing account:

1. Navigate to the management console and log in to Yandex Cloud or register a new account.
2. On the Yandex Cloud Billing page, make sure you have a billing account linked and it has the ACTIVE or TRIAL_ACTIVE status. If you do not have a billing account, create one and link a cloud to it.

If you have an active billing account, you can navigate to the cloud page to create or select a folder for your infrastructure to operate in.

Learn more about clouds and folders.

Required paid resourcesRequired paid resources

The infrastructure support cost for this tutorial includes:

• Fee for data operations and the amount of stored data (see Yandex Managed Service for YDB pricing).
• Fee for using a data stream (see Yandex Data Streams pricing).
• Fees for secret storage (see Yandex Lockbox pricing).
• Fee for data storage and data operations (see Yandex Object Storage pricing).
• Fee for requests to created API gateways and outbound traffic (see Yandex API Gateway pricing).
• Fee for queue requests and outbound traffic (see Yandex Message Queue pricing).
• Fee for function calls and computing resources allocated to execute the functions (see Yandex Cloud Functions pricing).

Set up your environmentSet up your environment

Download a projectDownload a project

Clone the yc-serverless-game repository:

git clone https://github.com/yandex-cloud-examples/yc-serverless-game.git

Register your Telegram botRegister your Telegram bot

Register your bot in Telegram and get a token.

1. To register a new bot, launch the BotFather bot and run this command:

   /newbot
   

2. In the name field, enter a name for the new bot, e.g., Serverless Game With WebSockets. This is the name users chatting with the bot will see.

3. In the username field, enter a username for the new bot, e.g., ServerlessGameWithWebSocketsBot. You can use it to locate the bot in Telegram. The username must end with ...Bot or ..._bot.

4. You will get the t.me/ServerlessGameWithWebSocketsBot address and token in response.

5. Save the username to the TG_BOT_LOGIN variable:

   echo "export TG_BOT_LOGIN=<bot_username>" >> ~/.bashrc && . ~/.bashrc
   echo $TG_BOT_LOGIN
   

6. Save the token to the TG_BOT_TOKEN variable:

   echo "export TG_BOT_TOKEN=<token>" >> ~/.bashrc && . ~/.bashrc
   echo $TG_BOT_TOKEN
   

Get an access tokenGet an access token

echo "export YC_IAM_TOKEN=$(yc iam create-token)" >> ~/.bashrc && . ~/.bashrc
echo $YC_IAM_TOKEN

echo "export OAUTH_TOKEN=$(yc config get token)" >> ~/.bashrc && . ~/.bashrc
echo $OAUTH_TOKEN

Create a service accountCreate a service account

1. Create a service account named sls-deploy and save its name to the SERVICE_ACCOUNT_GAME variable:

   export SERVICE_ACCOUNT_GAME=$(yc iam service-account create --name sls-deploy \
     --description "service account for serverless game" \
     --format json | jq -r .)
   
   echo $SERVICE_ACCOUNT_GAME
   

2. The id line in the command output will show the service account ID. Save it to the SERVICE_ACCOUNT_GAME_ID variable:

   echo "export SERVICE_ACCOUNT_GAME_ID=<service_account_ID>" >> ~/.bashrc && . ~/.bashrc
   

3. Assign the editor role to the service account:

   echo "export YC_FOLDER_ID=$(yc config get folder-id)" >> ~/.bashrc && . ~/.bashrc
   echo $YC_FOLDER_ID
   
   echo "export YC_CLOUD_ID=$(yc config get cloud-id)" >> ~/.bashrc && . ~/.bashrc
   echo $YC_CLOUD_ID
   
   yc resource-manager folder add-access-binding $YC_FOLDER_ID \
   --subject serviceAccount:$SERVICE_ACCOUNT_GAME_ID \
   --role editor
   

4. Create an authorized key for the service account:

   yc iam key create \
     --service-account-name sls-deploy \
     --output sls-deploy.sa
   
   echo "export SA_KEY_FILE=$PWD/sls-deploy.sa" >> ~/.bashrc && . ~/.bashrc
   echo $SA_KEY_FILE
   

5. Create a static access key for your service account:

   yc iam access-key create --service-account-id $SERVICE_ACCOUNT_GAME_ID
   

   Result:

   access_key:
       id: ajeibet3219********
       service_account_id: ajehr1tv2eo1********
       created_at: "2023-03-13T10:20:58.471421425Z"
       key_id: YCAS33CT2mPCVFh3K********
   secret: YCNhBcdvfDdssIuBa-FDl6zZz0MSky********
   

6. Save the key ID (key_id) to the AWS_ACCESS_KEY_ID variable and the secret key (secret) to the AWS_SECRET_ACCESS_KEY variable:

   echo "export AWS_ACCESS_KEY_ID=<key_ID>" >> ~/.bashrc && . ~/.bashrc
   echo $AWS_ACCESS_KEY_ID
   
   echo "export AWS_SECRET_ACCESS_KEY=<secret_key>" >> ~/.bashrc && . ~/.bashrc
   echo $AWS_SECRET_ACCESS_KEY
   

7. Configure the AWS CLI:

   aws configure
   

   Enter the following:

   • AWS Access Key ID: Service account’s access key ID (key_id) you got earlier.
   • AWS Secret Access Key: Service account secret key (secret) you got earlier.
   • Default region name: Use the ru-central1 value.
   • Default output format: Leave empty.

8. Check your configuration:

   echo $AWS_ACCESS_KEY_ID
   echo $AWS_SECRET_ACCESS_KEY
   aws configure list
   

Create Managed Service for YDB databasesCreate Managed Service for YDB databases

Create a database named game-data to store the game data and a database named data-streams for a Data Streams stream.

1. Create a database named game-data in serverless mode:

   yc ydb database create game-data --serverless
   

   Result:

   done (8s)
   id: etn0ejcvmjm4********
   folder_id: b1geoelk7fld********
   created_at: "2023-03-30T15:01:19Z"
   name: game-data
   status: PROVISIONING
   endpoint: grpcs://ydb.serverless.yandexcloud.net:2135/?database=/ru-central1/b1gia87mbaom********/etn0ejcvmjm4********
   serverless_database:
     storage_size_limit: "53687091200"
   location_id: ru-central1
   ...
   

2. Save the endpoint value from the previous command output to the YDB_ENDPOINT variable. In our example, it equals grpcs://ydb.serverless.yandexcloud.net:2135.

   echo "export YDB_ENDPOINT=<DB_Document_API_endpoint>" >> ~/.bashrc && . ~/.bashrc
   echo $YDB_ENDPOINT
   

3. Save the database value from the previous command output to the YDB_DATABASE variable. In our example, it equals /ru-central1/b1gia87mbaom********/etn0ejcvmjm4********.

   echo "export YDB_DATABASE=<table_name>" >> ~/.bashrc && . ~/.bashrc
   echo $YDB_DATABASE
   

4. Create a database named data-streams in serverless mode:

   yc ydb database create data-streams --serverless
   

   Result:

   done (7s)
   id: etn16k0e1757********
   folder_id: b1geoelk7fld********
   created_at: "2023-03-30T15:02:44Z"
   name: data-streams
   status: PROVISIONING
   endpoint: grpcs://ydb.serverless.yandexcloud.net:2135/?database=/ru-central1/b1gia87mbaom********/etn16k0e1757********
   serverless_database:
     storage_size_limit: "53687091200"
   location_id: ru-central1
   

5. Save the endpoint value from the previous command output to the YDB_DATA_STREAMS_ENDPOINT variable. In our example, it equals grpcs://ydb.serverless.yandexcloud.net:2135.

   echo "export YDB_DATA_STREAMS_ENDPOINT=<DB_Document_API_endpoint>" >> ~/.bashrc && . ~/.bashrc
   echo $YDB_DATA_STREAMS_ENDPOINT
   

6. Save the database value from the previous command output to the YDB_DATA_STREAMS_DATABASE variable. In our example, it equals /ru-central1/b1gia87mbaom********/etn16k0e1757********.

   echo "export YDB_DATA_STREAMS_DATABASE=<table_name>" >> ~/.bashrc && . ~/.bashrc
   echo $YDB_DATA_STREAMS_DATABASE
   

7. Make sure you did everything correctly:

   ydb \
     --endpoint $YDB_ENDPOINT \
     --database $YDB_DATABASE \
     --sa-key-file $SA_KEY_FILE \
   discovery whoami \
     --groups
   

   Result:

   User SID: ajeien4d11sc043********
   
   Group SIDs:
   all-users@well-known
   

Create a tableCreate a table

1. Navigate to the files directory in the yc-serverless-game folder.

2. Create a table using the db-example.sql file:

   ydb \
     --endpoint $YDB_ENDPOINT \
     --database $YDB_DATABASE \
     --sa-key-file $SA_KEY_FILE \
   scripting yql --file db-example.sql
   

3. Add a record for the initial configuration:

   ydb \
     --endpoint $YDB_ENDPOINT \
     --database $YDB_DATABASE \
     --sa-key-file $SA_KEY_FILE \
   scripting yql --file db-update.sql
   

4. Check the result:

   ydb \
     --endpoint $YDB_ENDPOINT \
     --database $YDB_DATABASE \
     --sa-key-file $SA_KEY_FILE \
   scheme describe Config
   

   Result:

   Columns:
   ┌────────────────────┬─────────┬────────┬─────┐
   | Name               | Type    | Family | Key |
   ├────────────────────┼─────────┼────────┼─────┤
   | name               | Utf8?   |        | K0  |
   | grid_cell_size     | Uint32? |        |     |
   | max_active_players | Uint8?  |        |     |
   | max_inactive_sec   | Int32?  |        |     |
   | player_size        | Uint32? |        |     |
   | transport          | Utf8?   |        |     |
   | world_size_x       | Uint32? |        |     |
   | world_size_y       | Uint32? |        |     |
   └────────────────────┴─────────┴────────┴─────┘
   
   Storage settings:
   Store large values in "external blobs": false
   
   Column families:
   ┌─────────┬──────┬─────────────┬────────────────┐
   | Name    | Data | Compression | Keep in memory |
   ├─────────┼──────┼─────────────┼────────────────┤
   | default |      | None        |                |
   └─────────┴──────┴─────────────┴────────────────┘
   
   Auto partitioning settings:
   Partitioning by size: true
   Partitioning by load: false
   Preferred partition size (Mb): 2048
   Min partitions count: 1
   

Create a Data Streams-enabled data streamCreate a Data Streams-enabled data stream

echo $YDB_DATA_STREAMS_DATABASE

aws kinesis create-stream \
  --endpoint https://yds.serverless.yandexcloud.net \
  --stream-name $YDB_DATA_STREAMS_DATABASE/notify-state-change \
  --shard-count 1

Create a Yandex Lockbox secretCreate a Yandex Lockbox secret

1. Create a secret named game-secrets and transfer the YDB_ENDPOINT and YDB_DATABASE variable values to it:

   yc lockbox secret create --name game-secrets \
     --description "The secrets for the serverless game" \
     --payload "[{'key': 'ydb_endpoint', 'text_value': $YDB_ENDPOINT},{'key': 'ydb_db', 'text_value': $YDB_DATABASE}]"
   

2. Save the ID of the new secret to the LOCKBOX_SECRET_ID variable:

   echo "export LOCKBOX_SECRET_ID=$(jq -r <<<  \
   "$(yc lockbox secret list --format json | jq '.[]' -c | grep game-secrets)" .id)"  \
   >> ~/.bashrc && . ~/.bashrc
   
   echo $LOCKBOX_SECRET_ID
   

3. Transfer the TG_BOT_TOKEN variable value to the secret:

   yc lockbox secret add-version --id $LOCKBOX_SECRET_ID \
   --payload "[{'key': 'tg_bot_token', 'text_value': '$TG_BOT_TOKEN'}]"
   

4. Transfer the keys to the secret (we will get their values later). For now, set them to null.

   yc lockbox secret add-version --id $LOCKBOX_SECRET_ID \
   --payload "[{'key': 'ymq_writer_key_id', 'text_value': 'null'},\
   {'key': 'ymq_writer_key_secret', 'text_value': 'null'},\
   {'key': 'ymq_capture_queue_url', 'text_value': 'null'},\
   {'key': 'yds_writer_key_id', 'text_value': 'null'},\
   {'key': 'yds_writer_key_secret', 'text_value': 'null'},\
   {'key': 'yds_state_change_stream', 'text_value': 'notify-state-change'},\
   {'key': 'yds_state_change_database', 'text_value': '$YDB_DATA_STREAMS_DATABASE'}]"
   

Deploy the projectDeploy the project

1. Navigate to the files directory in the yc-serverless-game folder.

2. Change the configuration for Object Storage. Since the bucket name must be unique, replace it with a custom bucket name in the following files:

   • serverless.yaml:

     sls-game-files:
       type: yc::ObjectStorageBucket
     

   • upload-to-s3.ts in the scripts directory:

     Bucket: 'sls-game-files',
     

     For example, specify sls-game-files-example instead of sls-game-files.

3. Set the APP_ENV variable to build your project:

   echo "export APP_ENV=production" >> ~/.bashrc && . ~/.bashrc
   echo $APP_ENV
   

4. Build and deploy the project. In the yc-serverless-game folder root, run the following commands one by one:

   nvm use
   nvm install
   npm ci
   
   npm run build
   npm run deploy
   

When you deploy the project, the following resources will be created in your working folder:

• Cloud Functions-enabled functions:

  • get-state
  • get-config
  • move
  • capture
  • state-change
  • login
  • auth
  • ws-connect
  • ws-message
  • ws-disconnect

• Service accounts:

  • functions-sa with the editor role
  • triggers-sa with the serverless.functions.invoker role
  • yds-reader-sa with the yds.admin role
  • yds-writer-sa with the yds.writer role
  • ymq-reader-sa with the ymq.reader role
  • ymq-writer-sa with the ymq.writer role
  • apigw-s3-viewer with the storage.viewer role
  • apigw-fn-caller with the serverless.functions.invoker role

• Object Storage bucket with the name you specified in the serverless.yaml file

• Message Queue named capturing-queue

Create access keys for service accountsCreate access keys for service accounts

The following service accounts were created when deploying the project:

• yds-writer-sa with the yds.writer role to write data to the Data Streams-enabled stream.
• ymq-writer-sa with the ymq.writer role to write data to the Message Queue.

1. Create a static access key for the yds-writer-sa service account:

   echo "export YDS_WRITER_SA_ID=$(jq -r <<<  \
   "$(yc iam service-account list --format json | jq '.[]' -c | grep yds-writer-sa)" .id)"  \
   >> ~/.bashrc && . ~/.bashrc
   
   yc iam access-key create --service-account-id $YDS_WRITER_SA_ID
   

   Result:

   access_key:
       id: ajeibet32197********
       service_account_id: ajehr6tv2eoo********
       created_at: "2023-03-13T10:20:58.471421425Z"
       key_id: YCASD3CT9mPCVFh3K********
   secret: YCNhBcdvfDdssIuBa-FDl6zZz0MSky********
   

2. Copy the key_id value and save it to the YDS_WRITER_KEY_ID variable:

   echo "export YDS_WRITER_KEY_ID=<key_ID>" >> ~/.bashrc && . ~/.bashrc
   echo $YDS_WRITER_KEY_ID
   

3. Copy the value of the secret named secret and save it to the YDS_WRITER_KEY_SECRET variable:

   echo "export YDS_WRITER_KEY_SECRET=<secret>" >> ~/.bashrc && . ~/.bashrc
   echo $YDS_WRITER_KEY_SECRET
   

4. Create a static access key for the ymq-writer-sa service account:

   echo "export YMQ_WRITER_SA_ID=$(jq -r <<<  \
   "$(yc iam service-account list --format json | jq '.[]' -c | grep ymq-writer-sa)" .id)"  \
   >> ~/.bashrc && . ~/.bashrc
   
   yc iam access-key create --service-account-id $YMQ_WRITER_SA_ID
   

5. Copy the key_id value and save it to the YMQ_WRITER_KEY_ID variable:

   echo "export YMQ_WRITER_KEY_ID=<key_ID>" >> ~/.bashrc && . ~/.bashrc
   
   echo $YMQ_WRITER_KEY_ID
   

6. Copy the value of the secret named secret and save it to the YMQ_WRITER_KEY_SECRET variable:

   echo "export YMQ_WRITER_KEY_SECRET=<secret>" >> ~/.bashrc && . ~/.bashrc
   echo $YMQ_WRITER_KEY_SECRET
   

Create a new secret version and deploy your project againCreate a new secret version and deploy your project again

1. Provide new values to the game-secrets secret:

   1. In the management console, select your working folder.

   2. Select Message Queue.

   3. Select capturing-queue.

   4. Copy the value from the URL field and save it to the YMQ_CAPTURE_QUEUE_URL variable:

      echo "export YMQ_CAPTURE_QUEUE_URL=<URL>" >> ~/.bashrc && . ~/.bashrc
      

   5. Check the variable values to transfer to the secret:

      echo $LOCKBOX_SECRET_ID
      echo $YMQ_WRITER_KEY_ID
      echo $YMQ_WRITER_KEY_SECRET
      echo $YDS_WRITER_KEY_ID
      echo $YDS_WRITER_KEY_SECRET
      echo $YMQ_CAPTURE_QUEUE_URL
      

   6. Transfer the values to the secret:

      yc lockbox secret add-version --id $LOCKBOX_SECRET_ID \
      --payload "[{'key': 'ymq_writer_key_id', 'text_value': '$YMQ_WRITER_KEY_ID'},\
      {'key': 'ymq_writer_key_secret', 'text_value': '$YMQ_WRITER_KEY_SECRET'},\
      {'key': 'ymq_capture_queue_url', 'text_value': '$YMQ_CAPTURE_QUEUE_URL'},\
      {'key': 'yds_writer_key_id', 'text_value': '$YDS_WRITER_KEY_ID'},\
      {'key': 'yds_writer_key_secret', 'text_value': '$YDS_WRITER_KEY_SECRET'}]"
      

2. Navigate to the yc-serverless-game folder root and deploy the project again:

   npm run deploy
   

Create an API Gateway API gatewayCreate an API Gateway API gateway

The following service accounts were created when deploying the project:

• apigw-s3-viewer with the storage.viewer role to read objects from the Object Storage bucket.
• apigw-fn-caller with the functions.functionInvoker role to invoke Cloud Functions-enabled functions.

1. Save the IDs of the apigw-s3-viewer and apigw-fn-caller service accounts to the APIGW_S3_VIEWER_ID and APIGW_FN_CALLER_ID variables:

   echo "export APIGW_S3_VIEWER_ID=$(jq -r <<<  \
   "$(yc iam service-account list --format json | jq '.[]' -c | grep apigw-s3-viewer)" .id)"  \
   >> ~/.bashrc && . ~/.bashrc
   
   echo "export APIGW_FN_CALLER_ID=$(jq -r <<<  \
   "$(yc iam service-account list --format json | jq '.[]' -c | grep apigw-fn-caller)" .id)"  \
   >> ~/.bashrc && . ~/.bashrc
   

2. Modify the API gateway specification. Navigateto the files directory in the yc-serverless-game folder and run the following command:

   cp apigw-example.yml apigw.yml
   

3. Get the IDs of the resources you created in the previous steps:

   echo $APIGW_S3_VIEWER_ID
   echo $APIGW_FN_CALLER_ID
   
   yc storage bucket list
   yc serverless function list
   

4. Make the following changes to the apigw.yml file:

   1. In all bucket: serverless-game-files lines, replace the bucket name with your own one.
   2. In all service_account_id: <sa-id-for-object-storage> lines, replace <sa-id-for-object-storage> with the $APIGW_S3_VIEWER_ID variable value.
   3. In all service_account_id: <sa-id-for-functions> lines, replace <sa-id-for-functions> with the $APIGW_FN_CALLER_ID variable value.
   4. In line 58, replace <yandex-cloud-nodejs-dev-get-state-function-id> with the yandex-cloud-nodejs-dev-get-state function ID.
   5. In line 65, replace <yandex-cloud-nodejs-dev-get-config-function-id> with the yandex-cloud-nodejs-dev-get-config function ID.
   6. In line 72, replace <yandex-cloud-nodejs-dev-move-function-id> with the yandex-cloud-nodejs-dev-move function ID.
   7. In line 79, replace <yandex-cloud-nodejs-dev-login-function-id> with the yandex-cloud-nodejs-dev-login function ID.
   8. In line 101, replace <yandex-cloud-nodejs-dev-ws-message-function-id> with the yandex-cloud-nodejs-dev-ws-message function ID.
   9. In line 106, replace <yandex-cloud-nodejs-dev-ws-connect-function-id> with the yandex-cloud-nodejs-dev-ws-connect function ID.
   10. In line 111, replace <yandex-cloud-nodejs-dev-ws-disconnect-function-id> with the yandex-cloud-nodejs-dev-ws-disconnect function ID.
   11. In line 118, replace <yandex-cloud-nodejs-dev-auth-function-id> with the yandex-cloud-nodejs-dev-auth function ID.

5. Deploy an API Gateway instance:

   yc serverless api-gateway create \
     --name serverless-game-api \
     --spec=apigw.yml \
     --description "for serverless-game-api"
   

   If you made an error in the API gateway specification, fix it and run this command:

   yc serverless api-gateway update \
     --name serverless-game-api \
     --spec=apigw.yml 
   

Connect a domain to a Telegram botConnect a domain to a Telegram bot

1. Run this command:

   yc serverless api-gateway get --name serverless-game-api
   

2. Copy the API gateway's service domain. You can find it in the domain field of the previous command output.

3. Find a Telegram bot named BotFather and type the /setdomain command.

4. Select your bot from the list and send it the API gateway's service domain. Add https:// before the domain name. For example, if the API gateway's service domain is d5dm1lba80md********.i9******.apigw.yandexcloud.net, the URL will be https://d5dm1lba80md********.i9******.apigw.yandexcloud.net.

Test the appTest the app

Follow the link you sent to the Telegram bot, sign in, and open a game.

The game offers player statistics. If the API gateway's service domain is d5dm1lba80md********.i9******.apigw.yandexcloud.net, the statistics for all players will be available at https://d5dm1lba80md********.i9******.apigw.yandexcloud.net/stats.html.

How to delete the resources you createdHow to delete the resources you created

To stop paying for the resources you created:

• Delete the Managed Service for YDB databases.
• Delete the Data Streams-enabled stream.
• Delete the Yandex Lockbox secret.
• Delete all objects from the bucket and then delete the empty Object Storage bucket.
• Delete the API Gateway.
• Delete the Cloud Functions-enabled functions.
• Delete the Message Queue.