How to: Connect to an Azure Fluid Relay service

Artikkeli
02/03/2023

This article walks through the steps to get your Azure Fluid Relay service provisioned and ready to use.

Important

Before you can connect your app to an Azure Fluid Relay server, you must provision an Azure Fluid Relay server resource on your Azure account.

Azure Fluid Relay service is a cloud-hosted Fluid service. You can connect your Fluid application to an Azure Fluid Relay instance using the AzureClient in the @fluidframework/azure-client package. AzureClient handles the logic of connecting your Fluid container to the service while keeping the container object itself service-agnostic. You can use one instance of this client to manage multiple containers.

The sections below will explain how to use AzureClient in your own application.

Connecting to the service

To connect to an Azure Fluid Relay instance, you first need to create an AzureClient. You must provide some configuration parameters including the tenant ID, service URL, and a token provider to generate the JSON Web Token (JWT) that will be used to authorize the current user against the service. The @fluidframework/test-client-utils package provides an InsecureTokenProvider that can be used for development purposes.

Caution

The InsecureTokenProvider should only be used for development purposes because using it exposes the tenant key secret in your client-side code bundle. This must be replaced with an implementation of ITokenProvider that fetches the token from your own backend service that is responsible for signing it with the tenant key. An example implementation is AzureFunctionTokenProvider. For more information, see How to: Write a TokenProvider with an Azure Function. Note that the id and name fields are arbitrary.

const user = { id: "userId", name: "userName" };

const config = {
  tenantId: "myTenantId",
  tokenProvider: new InsecureTokenProvider("myTenantKey", user),
  endpoint: "https://myServiceEndpointUrl",
  type: "remote",
};

const clientProps = {
  connection: config,
};

const client = new AzureClient(clientProps);

Now that you have an instance of AzureClient, you can start using it to create or load Fluid containers!

Token providers

The AzureFunctionTokenProvider is an implementation of ITokenProvider that ensures your tenant key secret is not exposed in your client-side bundle code. The AzureFunctionTokenProvider takes in your Azure Function URL appended by /api/GetAzureToken along with the current user object. Later on, it makes a GET request to your Azure Function by passing in the tenantId, documentId and userId/userName as optional parameters.

const config = {
  tenantId: "myTenantId",
  tokenProvider: new AzureFunctionTokenProvider(
    "myAzureFunctionUrl" + "/api/GetAzureToken",
    { userId: "userId", userName: "Test User" }
  ),
  endpoint: "https://myServiceEndpointUrl",
  type: "remote",
};

const clientProps = {
  connection: config,
};

const client = new AzureClient(clientProps);

Adding custom data to tokens

The user object can also hold optional additional user details. For example:

const userDetails = {
  email: "xyz@outlook.com",
  address: "Redmond",
};

const config = {
  tenantId: "myTenantId",
  tokenProvider: new AzureFunctionTokenProvider(
    "myAzureFunctionUrl" + "/api/GetAzureToken",
    { userId: "UserId", userName: "Test User", additionalDetails: userDetails }
  ),
  endpoint: "https://myServiceEndpointUrl",
  type: "remote",
};

Your Azure Function will generate the token for the given user that is signed using the tenant's secret key and return it to the client without exposing the secret itself.

Managing containers

The AzureClient API exposes createContainer and getContainer functions to create and get containers respectively. Both functions take in a container schema that defines the container data model. For the getContainer function, there is an additional parameter for the container id of the container you wish to fetch.

In the container creation scenario, you can use the following pattern:

const schema = {
  initialObjects: {
    /* ... */
  },
  dynamicObjectTypes: [
    /*...*/
  ],
};
const azureClient = new AzureClient(clientProps);
const { container, services } = await azureClient.createContainer(
  schema
);
const id = await container.attach();

The container.attach() call is when the container actually becomes connected to the service and is recorded in its blob storage. It returns an id that is the unique identifier to this container instance.

Any client that wants to join the same collaborative session needs to call getContainer with the same container id.

const { container, services } = await azureClient.getContainer(
  id,
  schema
);

For the further information on how to start recording logs being emitted by Fluid, see Logging and telemetry.

The container being fetched back will hold the initialObjects as defined in the container schema. See Data modeling on fluidframework.com to learn more about how to establish the schema and use the container object.

Getting audience details

Calls to createContainer and getContainer return two values: a container -- described above -- and a services object.

The container contains the Fluid data model and is service-agnostic. Any code you write against this container object returned by the AzureClient is reusable with the client for another service. An example is if you prototyped your scenario using TinyliciousClient, then all of your code interacting with the shared objects within the Fluid container can be reused when moving to using AzureClient.

The services object contains data that is specific to the Azure Fluid Relay service. This object contains an audience value that can be used to manage the roster of users that are currently connected to the container.

The following code demonstrates how you can use the audience object to maintain an updated view of all the members currently in a container.

const { audience } = containerServices;
const audienceDiv = document.createElement("div");

const onAudienceChanged = () => {
  const members = audience.getMembers();
  const self = audience.getMyself();
  const memberStrings = [];
  const useAzure = process.env.FLUID_CLIENT === "azure";

  members.forEach((member) => {
    if (member.userId !== (self ? self.userId : "")) {
      if (useAzure) {
        const memberString = `${member.userName}: {Email: ${member.additionalDetails ? member.additionalDetails.email : ""},
                        Address: ${member.additionalDetails ? member.additionalDetails.address : ""}}`;
        memberStrings.push(memberString);
      } else {
        memberStrings.push(member.userName);
      }
    }
  });
  audienceDiv.innerHTML = `
            Current User: ${self ? self.userName : ""} <br />
            Other Users: ${memberStrings.join(", ")}
        `;
};

onAudienceChanged();
audience.on("membersChanged", onAudienceChanged);

audience provides two functions that will return AzureMember objects that have a user ID and user name:

getMembers returns a map of all the users connected to the container. These values will change anytime a member joins or leaves the container.
getMyself returns the current user on this client.

audience also emits events for when the roster of members changes. membersChanged will fire for any roster changes, whereas memberAdded and memberRemoved will fire for their respective changes with the clientId and member values that have been modified. After any of these events fire, a new call to getMembers will return the updated member roster.

A sample AzureMember object looks like:

{
  "userId": "00aa00aa-bb11-cc22-dd33-44ee44ee44ee",
  "userName": "Test User",
  "connections": [
    {
      "id": "c699c3d1-a4a0-4e9e-aeb4-b33b00544a71",
      "mode": "write"
    },
    {
      "id": "00aa00aa-bb11-cc22-dd33-44ee44ee44ee",
      "mode": "write"
    }
  ],
  "additionalDetails": {
    "email": "xyz@outlook.com",
    "address": "Redmond"
  }
}

Alongside the user ID, name and additional details, AzureMember objects also hold an array of connections. If the user is logged into the session with only one client, connections will only have one value in it with the ID of the client, and whether is in read/write mode. However, if the same user is logged in from multiple clients (that is, they are logged in from different devices or have multiple browser tabs open with the same container), connections here will hold multiple values for each client. In the example data above, we can see that a user with name "Test User" and ID "00aa00aa-bb11-cc22-dd33-44ee44ee44ee" currently has the container open from two different clients. The values in the additionalDetails field match up to the values provided in the AzureFunctionTokenProvider token generation.

These functions and events can be combined to present a real-time view of the users in the current session.

Congratulations! You have now successfully connected your Fluid container to the Azure Fluid Relay service and fetched back user details for the members in your collaborative session!

Jaa