Guida introduttiva: Usare l'autenticazione on-behalf-of con Data API builder

In questa guida introduttiva, si usa il Quickstart 6 On-Behalf-Of Flow sample per eseguire Data API builder (DAB) con l'autenticazione delegata dell'utente. L'app Web autentica gli utenti con Microsoft Entra ID, invia token bearer a DAB e DAB scambia ciascun token con un token Azure SQL per l'utente autenticato.

L'esempio usa Azure SQL perché le SQL Server locali non possono accettare token di Microsoft Entra. Una WhoAmI vista eseguita SELECT SUSER_NAME() dimostra che SQL vede il chiamante effettivo, non l'identità gestita da DAB.

Prerequisiti

  • .NET 8 o versione successiva
  • Docker Desktop
  • PowerShell
  • strumenti .NET Aspire tooling per l'orchestrazione della compilazione
  • interfaccia della riga di comando di Azure per la configurazione di Microsoft Entra e la distribuzione in Azure
  • sqlpackage se si distribuisce il progetto di database
  • Una sottoscrizione Azure con autorizzazione per creare Azure SQL, App contenitore di Azure, Registro Azure Container, Log Analytics e un gruppo di risorse
  • Autorizzazione per creare registrazioni di applicazioni Microsoft Entra, creare un segreto client per un'app API, aggiungere l'autorizzazione delegata di database SQL di Azure user_impersonation e concedere il consenso dell'amministratore
  • Un utente o un gruppo di Microsoft Entra che può diventare l'amministratore Azure SQL Microsoft Entra

Cosa mostra l'esempio

  • Un'app Web statica che usa l'accesso tramite MSAL Browser.
  • Chiamate con token bearer dall'app web a DAB.
  • DAB configurato con il provider di autenticazione Microsoft Entra ID EntraId.
  • DAB user-delegated-auth configurato per lo scambio di token OBO.
  • Registrazione di un'applicazione API con un segreto del client per lo scambio OBO.
  • database SQL di Azure user_impersonation autorizzazione delegata con il consenso dell'amministratore.
  • Una semplice stringa di connessione Azure SQL senza le parole chiave User ID, Password o Authentication.
  • Entità DAB autenticate senza accesso anonimo.
  • Utenti contenuti di Azure SQL per i chiamanti autenticati.
  • Vista WhoAmI che restituisce SUSER_NAME() per convalidare l'identità del chiamante SQL.
  • Distribuzione e pulizia di Azure tramite script PowerShell in azure-infra.

Flusso di autenticazione

Hop Authentication
Dall'utente all'app Web Accesso al browser MSAL con Microsoft Entra ID
App Web per l'API DAB Token di connessione per il gruppo di destinatari dell'API DAB
Ruolo DELL'API DAB authenticated
DaB a Azure SQL Token OBO per l'utente connesso effettivo

Confronta con la serie

Step Cosa cambia
Previous Usare la sicurezza a livello di riga di SQL filtra le righe in SQL, ma SQL autentica comunque l'identità del servizio DAB.
Questa guida rapida Utilizza OBO in modo che Azure SQL autentichi l'utente effettivamente connesso ai fini dell'auditing e dei criteri basati sull'identità dell'utente.
Avanti Configurare l'autenticazione OBO illustra in dettaglio le proprietà di configurazione OBO.

Comportamento esclusivo di Azure

OBO richiede Azure SQL con l'autenticazione di Microsoft Entra. Un contenitore locale SQL Server non può accettare token Microsoft Entra, quindi il percorso OBO completo è Azure-only.

Usare un Azure SQL stringa di connessione bare in modo che DAB possa inserire il token OBO per utente in ogni richiesta autenticata.

Server=tcp:<server>.database.windows.net,1433;Database=<database>;Encrypt=True;TrustServerCertificate=False;

Non includere questi valori nel stringa di connessione OBO:

  • User ID
  • Password
  • Authentication

Importante

Se il stringa di connessione include Authentication=, le librerie client SQL rifiutano la richiesta quando DAB fornisce anche un token di accesso.

Utilizza l'esempio

Clonare il repository di esempio.

git clone https://github.com/Azure-Samples/dab-2.0-quickstart-web_entra-api_entra-db_entra-obo.git
cd dab-2.0-quickstart-web_entra-api_entra-db_entra-obo

Ripristinare gli strumenti locali.

dotnet tool restore

Accedere ad Azure.

az login

Distribuisci l'esempio su Azure.

pwsh ./azure-infra/azure-up.ps1

Lo script di distribuzione effettua il provisioning di risorse Azure SQL e App contenitore di Azure per DAB, l'app Web, MCP Inspector e SQL Commander. Esegue anche la configurazione di Microsoft Entra, crea il segreto client dell'app API, aggiunge l'autorizzazione delegata di database SQL di Azure user_impersonation, concede il consenso dell'amministratore, distribuisce il database, crea utenti contenuti e configura DAB per OBO.

Dopo la distribuzione, aprire l'URL dell'app Web stampato dallo script. Accedere e verificare che il badge SQL Server visualizzi il nome dell'entità utente. Il badge mostra l'entità WhoAmI supportata da SELECT SUSER_NAME().

Le richieste API anonime devono restituire 401 Unauthorized.

Eseguire la pulizia delle risorse Azure e delle registrazioni delle app al termine.

pwsh ./azure-infra/azure-down.ps1

File chiave

Percorso Purpose
data-api/dab-config.json Abilita user-delegated-auth, disabilita la cache, configura EntraIde espone l'entità WhoAmI di visualizzazione.
database/Views/WhoAmI.sql Definisce SELECT SUSER_NAME() AS UserName per la verifica dell'identità.
web-app/index.html Mostra l'utente connesso e il badge di identità SQL.
web-app/app.js Coordina l'accesso, gli aggiornamenti delle pagine e l'aggiornamento delle identità.
web-app/dab.js Invia richieste di bearer-token a DAB e legge WhoAmI.
azure-infra/entra-setup.ps1 Crea le registrazioni dell’app in Microsoft Entra, crea il segreto client dell’API, aggiunge l’autorizzazione delegata user_impersonation per database SQL di Azure e concede il consenso dell’amministratore.
azure-infra/resources.bicep Definisce le risorse di Azure e passa a DAB la semplice stringa di connessione di Azure SQL e le impostazioni OBO.
azure-infra/post-provision.ps1 Distribuisce il database, imposta l'amministratore Azure SQL Microsoft Entra, crea utenti indipendenti e configura i valori dell'ambiente OBO.

Usare GitHub Copilot per ricreare questo esempio

Aprire l'area di lavoro in cui si vuole creare l'esempio in Visual Studio Code, passare GitHub Copilot alla modalità agente e incollare questa richiesta.

You are GitHub Copilot running in agent mode. Recreate the Data API builder Quickstart 6 On-Behalf-Of Flow sample as a complete Azure-only project in the current VS Code workspace under `quickstart-06-on-behalf-of`. Build a static SPA with MSAL browser sign-in, DAB with Microsoft Entra bearer-token validation and OBO user-delegated authentication, Azure SQL, REST, GraphQL, MCP, .NET Aspire build orchestration, SQL Commander, MCP Inspector, and Azure Container Apps deployment scripts. DAB is the only API, GraphQL, and MCP layer over SQL. SQL must authenticate the actual signed-in user, not the DAB managed identity or service principal.

Source repository: https://github.com/Azure-Samples/dab-2.0-quickstart-web_entra-api_entra-db_entra-obo. If internet access is available, inspect or clone this repository before you create files. Reuse and adapt its files as closely as possible, especially `web-app/`, `data-api/`, `database/`, `aspire-apphost/`, `mcp-inspector/`, `azure-infra/`, scripts, and README patterns. The goal is to implement the published quickstart, not to invent a different sample. If the repository differs from this prompt or the current Data API builder docs, prefer the current docs for product behavior.

Minimize user interaction. Use the defaults in this prompt and make reasonable best guesses for noncritical choices. Do not ask for a root folder or project folder name; use the current VS Code workspace and the default subfolder. Ask only when you need approval for resource changes, secrets, permissions, materially higher cost, external account choices, or an ambiguous requirement that affects the architecture.

Azure-only constraint: do not build a local SQL Server OBO path. Local SQL Server cannot accept Microsoft Entra tokens. Use local tooling only for project generation, web app development, DAB config validation where possible, container builds, and database package builds.

Start with a short plan and proceed with safe defaults before you create files or run commands. Use the default `WhoAmI` view unless the user explicitly asks for additional schema. Ask only these questions if the values aren't already available from the environment or prior context:

- Which Azure subscription, primary region, fallback region, resource group, and tenant should the sample use? Default fallback region: `westus2` if the primary region can't provision Azure SQL or Container Apps.
- Should I create new SPA and API app registrations or reuse existing registrations?
- Confirm that the API app can use a client secret. OBO requires a confidential client.
- Confirm that the API app should receive Azure SQL Database delegated `user_impersonation` permission and admin consent.
- Which Microsoft Entra user or group should become the Azure SQL Microsoft Entra admin?
- Which signed-in users or groups should become contained database users for validation?
- Do you approve creating billable Azure resources, app registrations, and an API app client secret if deployment starts?

After the answers, show a checklist and ask for approval before implementation. Include phases for scaffold, Entra setup, database package, Azure infrastructure, post-provision, validation, and cleanup. Do not run `az`, `az ad`, `azd`, or Azure deployment commands that create or change resources until the user explicitly approves the exact command set.

After approval, continue working without asking status-check questions. If a command, build, container, endpoint, or validation step fails, inspect the error, adjust the project, rerun the step, and continue. Keep iterating until the sample runs end-to-end or you hit a blocker that requires user action.

Use cost-first Azure defaults. Choose the cheapest option that satisfies the quickstart requirements: use a free Azure SQL database offer when the subscription and region support it and it supports Microsoft Entra/OBO validation; otherwise choose the lowest-cost SQL option that supports user-delegated authentication. Use Azure Container Apps consumption, minimal CPU and memory, Basic Azure Container Registry, minimal Log Analytics retention, and no always-on or dedicated plans unless required. Prioritize finishing the project. Treat regional provisioning limits as expected adjustment points, not failures: if the primary region can't provision a required service or free SQL option, use the approved fallback region such as `westus2`, and continue the deployment. Ask the user only when both the primary and fallback regions can't satisfy the requirements, when a change would materially increase cost, when a new permission is required, or when you need approval for Azure commands that create or change resources beyond the already-approved plan. Keep every resource minimal, but make the web interface neat and approachable: small code footprint, responsive layout, clear status messages, accessible labels, and simple styling that is polished rather than austere.

Verify prerequisites and report only missing items: .NET SDK, Docker Desktop running, PowerShell, Azure CLI signed in, permission to create app registrations and grant admin consent, `sqlpackage`, .NET Aspire tooling, and the DAB CLI. Use these docs while building:

- DAB CLI reference: https://learn.microsoft.com/azure/data-api-builder/command-line/
- `dab configure` OBO options: https://learn.microsoft.com/azure/data-api-builder/command-line/dab-configure
- `dab validate`: https://learn.microsoft.com/azure/data-api-builder/command-line/dab-validate
- DAB MCP overview: https://learn.microsoft.com/azure/data-api-builder/mcp/overview
- OBO concept: https://learn.microsoft.com/azure/data-api-builder/concept/security/authenticate-on-behalf-of
- User-delegated auth configuration: https://learn.microsoft.com/azure/data-api-builder/configuration/data-source#user-delegated-auth

Create this structure under the sample folder:

- `azure-infra/` for Bicep, `azure-up.ps1`, `azure-down.ps1`, `entra-setup.ps1`, `entra-teardown.ps1`, `resources.bicep`, and `post-provision.ps1`.
- `data-api/` for `dab-config.json` and a DAB Dockerfile that bakes the config into the image.
- `database/` for a SQL Database Project, seed data, and `Views/WhoAmI.sql`.
- `web-app/` for static HTML, CSS, and JavaScript with MSAL browser support.
- `aspire-apphost/` for build orchestration only.
- `mcp-inspector/` for MCP Inspector container assets and nginx same-origin proxy config.

Handle secrets first. Add `.env`, `**/bin`, and `**/obj` to `.gitignore` before writing secrets or local configuration. Store the API client secret only in local `.env` files for local preparation and in Azure Key Vault or Azure Container Apps secrets for Azure. Never inline secret values in Bicep, PowerShell scripts, generated JSON, logs, or reports. Generate secret references for Container Apps instead of plaintext environment values. Never print tokens, passwords, or client secret values. Redact all secret values as `***redacted***`.

Configure DAB CORS before you start or deploy the web app. Do not leave `runtime.host.cors.origins` as `[]`. Set it to include the exact web app origins, including scheme and port: any local web origin used for development and the deployed Azure Container Apps web FQDN. Keep `allow-credentials` set to `false` because this SPA sends bearer tokens, not browser credentials or cookies. Direct REST, GraphQL, or Swagger requests can succeed even when the browser blocks JavaScript fetch calls, so browser-origin CORS must be configured and validated separately.

Use this DAB CLI workflow for config shaping and validation where possible:

```dotnetcli
dab init --database-type mssql --connection-string "@env('DATABASE_CONNECTION_STRING')" --auth.provider EntraID --auth.audience "@env('ENTRA_AUDIENCE')" --auth.issuer "@env('ENTRA_ISSUER')" --rest.enabled true --graphql.enabled true --mcp.enabled true
dab configure --data-source.user-delegated-auth.enabled true --data-source.user-delegated-auth.provider EntraId --data-source.user-delegated-auth.database-audience "https://database.windows.net"
dab add WhoAmI --source dbo.vw_WhoAmI --source.type view --source.key-fields "UserName" --permissions "authenticated:read" --mcp.dml-tools true
dab validate --config data-api/dab-config.json
```

Use a bare Azure SQL connection string so DAB can inject the per-user OBO access token. Do not include `User ID`, `Password`, or `Authentication`.

```text
Server=tcp:<server>.database.windows.net,1433;Database=<database>;Encrypt=True;TrustServerCertificate=False;
```

Use this DAB data-source shape for OBO:

```json
{
	"data-source": {
		"database-type": "mssql",
		"connection-string": "@env('DATABASE_CONNECTION_STRING')",
		"user-delegated-auth": {
			"enabled": true,
			"provider": "EntraId",
			"database-audience": "https://database.windows.net"
		}
	}
}
```

Create `database/Views/WhoAmI.sql` to prove SQL sees the signed-in user.

```sql
CREATE VIEW dbo.vw_WhoAmI AS
SELECT CAST(SUSER_NAME() AS nvarchar(256)) AS UserName;
```

Implement the SPA with MSAL browser. `web-app/dab.js` must send bearer tokens to DAB on every protected request.

```javascript
export async function getAuthHeaders() {
	const token = await acquireAccessToken();
	return { Authorization: `Bearer ${token}` };
}
```

For Azure, bake `dab-config.json` into the DAB image. Do not rely on volume mounts in Azure Container Apps.

```dockerfile
FROM mcr.microsoft.com/azure-databases/data-api-builder:latest
COPY dab-config.json /App/dab-config.json
```

Before any Azure post-provision command, list the exact `az`, `az acr`, `az containerapp`, and `sqlpackage` commands you intend to run and wait for explicit user approval. Post-provision in this order: deploy dacpac, set the Azure SQL Microsoft Entra admin, create contained database users or groups for validation, grant access to demo objects and `WhoAmI`, replace placeholders, build and push the DAB image, then update Container Apps.

```powershell
dotnet build database/database.sqlproj -c Release
sqlpackage /Action:Publish /SourceFile:database/bin/Release/database.dacpac /TargetConnectionString:"$sqlConn" /p:BlockOnPossibleDataLoss=false
az acr build --registry $acrName --image dab-api:latest --file ./data-api/Dockerfile ./data-api/
az containerapp update --name $dabAppName --resource-group $resourceGroup --image "$acrName.azurecr.io/dab-api:latest"
```

Deploy MCP Inspector with a same-origin proxy pattern and set `MCP_SERVER_URL` to the DAB `/mcp` endpoint.

```nginx
location /mcp {
	proxy_pass http://127.0.0.1:6277;
	proxy_http_version 1.1;
	proxy_set_header Upgrade $http_upgrade;
	proxy_set_header Connection "upgrade";
	proxy_buffering off;
}
```

Deploy SQL Commander with env var `ConnectionStrings__db` and ensure the connection string includes `TrustServerCertificate=true`.

```text
ConnectionStrings__db=Server=<server>.database.windows.net;Database=<database>;User Id=<user>;Password=<password>;TrustServerCertificate=true
```

Validation must prove OBO, not only API authentication:

- A direct Azure SQL query confirms the database is reachable, the deployed objects exist, and required contained users or groups exist.
- DAB `/health` returns a 2xx response.
- The web site returns a successful HTTP response.
- A browser-origin request from each web app origin receives an `Access-Control-Allow-Origin` response header that matches that origin.
- The web app signs in with Microsoft Entra ID.
- Signed-in REST, GraphQL, and MCP calls include bearer headers and reach DAB under the `authenticated` role.
- The `WhoAmI` entity returns the signed-in user's UPN from `SUSER_NAME()`.
- `WhoAmI` does not return the DAB managed identity, service principal, or Container App identity.
- Anonymous REST and GraphQL calls return `401`.
- The DAB Container App database connection string contains no SQL password, no `User ID`, and no `Authentication` keyword.
- The API client secret exists only as a secret reference or redacted local value.
- MCP Inspector connects to DAB MCP with streamable HTTP.
- SQL Commander can browse the deployed schema.
- Required contained users or groups exist in Azure SQL.

Do not report final URLs, asset locations, or a success summary until you directly verify database connectivity and query results, a 2xx DAB health response, and a successful web site response. This validation ensures the sample works without requiring the developer to check.

Troubleshoot with these checks:

- OBO token exchange fails: verify the API app has Azure SQL Database delegated `user_impersonation` permission and admin consent.
- SQL login fails for a token-identified principal: add the signed-in user or group as a contained user in the database.
- DAB returns 401 for valid bearer tokens: verify audience and issuer values in `dab-config.json`.
- SQL sees the service identity instead of the user: verify `user-delegated-auth`, the API client secret, and the bare SQL connection string.

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