[Yandex Cloud documentation](../../index.md) > [Tutorials](../index.md) > [Serverless technologies](index.md) > Serverless-based backend > Connecting to a YDB database from a Node.js function in Cloud Functions # Connecting to a Yandex Managed Service for YDB database from a Yandex Cloud Functions function in Node.js {% note info %} This tutorial is intended for Linux users. On Windows, you can follow it in [WSL](https://docs.microsoft.com/en-us/windows/wsl/about). {% endnote %} You will create a [function](../../functions/concepts/function.md) with a [Node.js app](https://ydb.tech/docs/en//reference/ydb-sdk/example/example-nodejs) that will run simple queries against a [YDB](https://ydb.tech/) database. You will deploy your app using Bash scripts and use the `tcs` command to compile it. Use a metadata service to authorize your function with an associated [service account](../../iam/concepts/users/service-accounts.md) in YDB. The application creates a YDB database connection driver, a session, and a transaction, and runs a query using the `ydb` library. This library is installed as a [dependency](../../functions/lang/nodejs/dependencies.md) when creating a [function version](../../functions/concepts/function.md#version). The database connection parameters are provided to the application using environment variables. To set up a connection to a YDB database: 1. [Get your cloud ready](#before-begin). 1. [Set up your environment](#prepare-environment). 1. [Create a service account](#create-sa). 1. [Create an authorized key](#create-key). 1. [Create a YDB database](#create-database). 1. [Create a function](#create-function). 1. [Test the function](#test-function). If you no longer need the resources you created, [delete them](#clear-out). ## Get your cloud ready {#before-begin} Sign up for Yandex Cloud and create a [billing account](../../billing/concepts/billing-account.md): 1. Navigate to the [management console](https://console.yandex.cloud) and log in to Yandex Cloud or create a new account. 1. On the **[Yandex Cloud Billing](https://center.yandex.cloud/billing/accounts)** page, make sure you have a billing account linked and it has the `ACTIVE` or `TRIAL_ACTIVE` [status](../../billing/concepts/billing-account-statuses.md). If you do not have a billing account, [create one](../../billing/quickstart/index.md) and [link](../../billing/operations/pin-cloud.md) a cloud to it. If you have an active billing account, you can create or select a [folder](../../resource-manager/concepts/resources-hierarchy.md#folder) for your infrastructure on the [cloud page](https://console.yandex.cloud/cloud). [Learn more about clouds and folders here](../../resource-manager/concepts/resources-hierarchy.md). ### Required paid resources {#paid-resources} The infrastructure support cost for this tutorial includes: * Fee for using the function (see [Yandex Cloud Functions pricing](../../functions/pricing.md)). * Fee for querying the database (see [Yandex Managed Service for YDB pricing](../../ydb/pricing/serverless.md)). ## Set up your environment {#prepare-environment} 1. Clone the [repository](https://github.com/yandex-cloud-examples/yc-ydb-connect-from-serverless-function) using Git: ```bash git clone https://github.com/yandex-cloud-examples/yc-ydb-connect-from-serverless-function.git ``` 1. Install and initialize the [Yandex Cloud CLI](../../cli/quickstart.md). 1. Go to the project root directory: ```bash cd ~/yc-ydb-connect-from-serverless-function ``` Make sure to run all further commands in this directory. 1. Install [jq](https://stedolan.github.io/jq/download/): ```bash sudo apt-get install jq ``` 1. Install [Node.js](https://nodejs.org/en/download/package-manager/): ```bash curl --fail --silent --show-error --location https://deb.nodesource.com/setup_current.x | sudo -E bash - \ sudo apt-get install -y nodejs ``` 1. Install the dependencies: ```bash npm install ``` Result: ```text up to date, audited 269 packages in 1s 29 packages are looking for funding run `npm fund` for details found 0 vulnerabilities ``` ## Create a service account {#create-sa} {% list tabs group=instructions %} - Management console {#console} 1. In the [management console](https://console.yandex.cloud), select the [folder](../../resource-manager/concepts/resources-hierarchy.md#folder) where you want to create your service account. 1. Navigate to **Identity and Access Management**. 1. Click **Create service account**. 1. Name the service account: `sa-function`. 1. Click **Add role** and select `editor`. 1. Click **Create**. - CLI {#cli} 1. [Create](../../iam/operations/sa/create.md#create-sa) a service account: ```bash yc iam service-account create --name sa-function ``` Result: ```text id: aje028do8n9r******** folder_id: b1g681qpemb4******** created_at: "2023-08-23T06:24:49.759304161Z" name: sa-function ``` 1. [Assign](../../iam/operations/sa/set-access-bindings.md#assign-role-to-sa) the `editor` [role](../../iam/concepts/access-control/roles.md) to the service account: ```bash yc resource-manager folder add-access-binding \ --role editor \ --subject serviceAccount: ``` Result: ```text ...1s...done (4s) effective_deltas: - action: ADD access_binding: role_id: viewer subject: id: aje028do8n9r******** type: serviceAccount ``` For more information about the commands, see the [CLI reference](../../cli/cli-ref/iam/cli-ref/service-account/index.md). - Terraform {#tf} If you do not have Terraform yet, [install it and configure the Yandex Cloud provider](../infrastructure-management/terraform-quickstart.md#install-terraform). To manage infrastructure using Terraform under a service account or user accounts (a Yandex account, a federated account, or a local user), [authenticate](../../terraform/authentication.md) using the appropriate method. 1. In the configuration file, define the service account properties: ```hcl resource "yandex_iam_service_account" "sa" { name = "sa-function" } ``` For more information about the resources you can create with Terraform, see [this provider guide](../../terraform/resources/iam_service_account.md). 1. Make sure the configuration files are correct. 1. In the terminal, navigate to the directory with your configuration file. 1. Run a check using this command: ```bash terraform plan ``` If the configuration is correct, the terminal will display a list of the resources and their settings. Otherwise, Terraform will show any detected errors. 1. Deploy the cloud resources. 1. If the configuration is correct, run this command: ```bash terraform apply ``` 1. To confirm resource creation, type `yes` and press **Enter**. - API {#api} To create a service account and assign it a [role](../../iam/concepts/access-control/roles.md), use the [create](../../iam/api-ref/ServiceAccount/create.md) and [setAccessBindings](../../iam/api-ref/ServiceAccount/setAccessBindings.md) methods for the [ServiceAccount](../../iam/api-ref/ServiceAccount/index.md) resource. {% endlist %} ## Create an authorized key {#create-key} {% list tabs group=instructions %} - Management console {#console} 1. In the [management console](https://console.yandex.cloud), select the folder the service account belongs to. 1. Navigate to **Identity and Access Management**. 1. In the left-hand panel, select ![FaceRobot](../../_assets/console-icons/face-robot.svg) **Service accounts**. 1. In the list that opens, select the `sa-function` service account. 1. Click **Create new key** in the top panel. 1. Select **Create authorized key**. 1. Select the encryption algorithm. 1. Enter a description for the [authorized key](../../iam/concepts/authorization/key.md) so you can easily find it in the management console. 1. Save both the public and private parts of the authorized key to the `yc-ydb-connect-from-serverless-function/service_account_key_file.json` file: ```json { "service_account_id": "", "key_algorithm": "RSA_2048", "public_key": "-----BEGIN PUBLIC KEY-----\n...\n-----END PUBLIC KEY-----\n", "private_key": "-----BEGIN PRIVATE KEY-----\n...\n-----END PRIVATE KEY-----\n" } ``` - CLI {#cli} Run this command: ```bash yc iam key create --service-account-name sa-function -o service_account_key_file.json ``` For more information about the `yc iam key create` command, see the [CLI reference](../../cli/cli-ref/iam/cli-ref/key/create.md). If successful, the private part of the authorized key (`privateKey`) and the ID of its public part (`id`) will be written to the `service_account_key_file.json` file. - Terraform {#tf} 1. In the configuration file, specify the authorized key properties: ```hcl resource "yandex_iam_service_account_key" "sa-auth-key" { service_account_id = "" key_algorithm = "RSA_2048" } ``` For more information about the resources you can create with Terraform, see [this provider guide](../../terraform/resources/iam_service_account_key.md). 1. Make sure the configuration files are correct. 1. In the terminal, navigate to the directory with your configuration file. 1. Run a check using this command: ```bash terraform plan ``` If the configuration is correct, the terminal will display a list of the resources and their settings. Otherwise, Terraform will show any detected errors. 1. Deploy the cloud resources. 1. If the configuration is correct, run this command: ```bash terraform apply ``` 1. To confirm resource creation, type `yes` and press **Enter**. - API {#api} To create an authorized access key, use the [create](../../iam/api-ref/Key/create.md) method for the [Key](../../iam/api-ref/Key/index.md) resource. {% endlist %} ## Create a YDB database {#create-database} {% list tabs group=instructions %} - Management console {#console} 1. In the [management console](https://console.yandex.cloud), select the folder where you want to create a database. 1. Navigate to **Managed Service for YDB**. 1. Click **Create a database**. 1. Name the database. The naming requirements are as follows: * Length: between 3 and 63 characters. * It can only contain lowercase Latin letters, numbers, and hyphens. * It must start with a letter and cannot end with a hyphen. 1. Under **Database type**, select `Serverless`. 1. Click **Create a database**. Wait for the database to start. While being created, the database will have the `Provisioning` status. Once it is ready for use, its status will change to `Running`. 1. Click the name of the database you created. 1. Save the value of the **Endpoint** field from the **Connection** section. You will need it in the next step. {% endlist %} ## Create a function {#create-function} {% note info %} Before creating a function, make sure the `.env` file and the `create-func.sh` and `create-func-ver.sh` files from the `deploy` directory have the `LF` (line feed) character set. {% endnote %} 1. Go to the project root directory: ```bash cd ~/yc-ydb-connect-from-serverless-function ``` 1. Edit the `.env` file: * `ENDPOINT`: First part of the previously saved **Endpoint** field value (preceding `/?database=`), e.g., `grpcs://ydb.serverless.yandexcloud.net:2135`. * `DATABASE`: Second part of the previously saved **Endpoint** field value (following `/?database=`), e.g., `/ru-central1/r1gra875baom********/g5n22e7ejfr1********`. * `FUNCTION_NAME`: Function name, `func-test-ydb`. * `FOLDER_ID`: Folder ID. * `SERVICE_ACCOUNT_ID`: `sa-function` service account ID. 1. Create a function: ```bash ./deploy/create-func.sh ``` This script creates a new function in your folder and makes it public. 1. Create a function version: ```bash ./deploy/create-func-ver.sh ``` Result: ```text npx tsc --build tsconfig.json rm: Cannot delete '../build/func.zip': File or folder does not exist. adding: queries/ (stored 0%) adding: queries/clients-table.js (deflated 57%) adding: queries/helpers.js.map (deflated 43%) adding: queries/helpers.js (deflated 48%) adding: queries/clients-table.js.map (deflated 59%) adding: index.js (deflated 49%) adding: index.js.map (deflated 56%) adding: database.js.map (deflated 62%) adding: index-local.js (deflated 42%) adding: package.json (deflated 55%) adding: database.js (deflated 60%) adding: index-local.js.map (deflated 43%) yc function version create func-test-ydb done (27s) id: abcd2d363b4b******** function_id: efghm9el0ja9******** created_at: "2023-08-15T07:41:07.591Z" runtime: nodejs16 entrypoint: index.handler resources: memory: "268435456" execution_timeout: 5s service_account_id: hijk3hlu8gqe******** image_size: "33497088" status: ACTIVE tags: - $latest log_group_id: lmnoivbe341g******** environment: DATABASE: /ru-central1/b1gia87mbaom********/etnilt3o6v9e******** ENDPOINT: grpcs://ydb.serverless.yandexcloud.net:2135 log_options: folder_id: pqrs81qpemb******** ``` ## Test the function {#test-function} {% list tabs group=instructions %} - Management console {#console} 1. In the [management console](https://console.yandex.cloud), select the folder containing the function. 1. Navigate to **Cloud Functions**. 1. Select the `func-test-ydb` function. 1. Navigate to the **Overview** tab. 1. In the **Link to invoke** field, click the link. 1. In your browser address bar, add the `api_key` parameter to the link, e.g., `?api_key=b95`: ```http request https://functions.yandexcloud.net/efghm9el0ja9********?api_key=b95 ``` 1. If you database is connected, a table named `b95` with a single record will be created. A JSON message will appear on the page, e.g.: ```json { "info": "b95 table created, one record inserted" } ``` {% endlist %} ## How to delete the resources you created {#clear-out} To stop paying for the resources you created: 1. [Delete the database](../../ydb/operations/manage-databases.md#delete-db). 1. [Delete the function](../../functions/operations/function/function-delete.md).