topic Re: Implementing RLS on Embedded where report token is received by Azure AD REST call. in Developer

Implementing RLS on Embedded where report token is received by Azure AD REST call.

Anonymous — Fri, 01 Jun 2018 15:41:38 GMT

Hello Everyone,

I am attempting to implement RLS in our .Net Core application of embedding power BI. here is our current TokenDataCall

        /// <summary>
        /// Gets Token Credentials and access token for use with authenticating PowerBi api calls
        /// </summary>
        /// <returns></returns>
        public async Task<(TokenCredentials tokenCredentials, string accessToken)> GetTokenDataAsync()
        {
            try
            {
                var authorityUrl = $"{_azureSettings.Instance}{_azureSettings.TenantId}/oauth2/token";

                var oauthEndpoint = new Uri(authorityUrl);

                using (var client = new HttpClient())
                {
                    var result = await client.PostAsync(oauthEndpoint, new FormUrlEncodedContent(new[]
                    {
                        new KeyValuePair<string, string>("resource", _powerBiSettings.ResourceAddress),
                        new KeyValuePair<string, string>("client_id", _azureSettings.ClientId),
                        new KeyValuePair<string, string>("grant_type", "password"),
                        new KeyValuePair<string, string>("username", _powerBiSettings.MasterUser),
                        new KeyValuePair<string, string>("password", _powerBiSettings.MasterKey),
                        new KeyValuePair<string, string>("scope", "openid"),
                    }));

                    var content = await result.Content.ReadAsStringAsync();

                    var authenticationResult = JsonConvert.DeserializeObject<OAuthResult>(content);
                    return (new TokenCredentials(authenticationResult.AccessToken, _azureSettings.TokenType), authenticationResult.AccessToken);
                }
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, ex.Message);
                throw;
            }
        }

        private class OAuthResult
        {
            [JsonProperty("token_type")]
            public string TokenType { get; set; }
            [JsonProperty("scope")]
            public string Scope { get; set; }
            [JsonProperty("expires_in")]
            public int ExpiresIn { get; set; }
            [JsonProperty("ext_expires_in")]
            public int ExtExpiresIn { get; set; }
            [JsonProperty("expires_on")]
            public int ExpiresOn { get; set; }
            [JsonProperty("not_before")] 
            public int NotBefore { get; set; }
            [JsonProperty("resource")]
            public Uri Resource { get; set; }
            [JsonProperty("access_token")]
            public string AccessToken { get; set; }
            [JsonProperty("refresh_token")]
            public string RefreshToken { get; set; }
        }

I haven't found any documentation on how to use this token call to pass in the "Role" and "username" parameters found here.

https://docs.microsoft.com/en-us/power-bi/developer/embedded-row-level-security

Is there anyway to add those into the dictionary and for it to return the correct report access token with filtered data?

Thanks,

Re: Implementing RLS on Embedded where report token is received by Azure AD REST call.

v-jiascu-msft — Mon, 04 Jun 2018 13:51:54 GMT

Hi @Anonymous,

If you use the Rest API, it could be like below. Please refer to #applying-user-and-role-to-an-embed-token.

{   
    "accessLevel": "View",
    "identities": [     
        {      
            "username": "EffectiveIdentity",
            "roles": [ "Role1", "Role2" ],
            "datasets": [ "fe0a1aeb-f6a4-4b27-a2d3-b5df3bb28bdc" ]
        }   
    ] 
}

I tested it successfully with Postman.

Best Regards,

Dale

Re: Implementing RLS on Embedded where report token is received by Azure AD REST call.

Anonymous — Wed, 06 Jun 2018 13:50:19 GMT

Fixed,

I was confused because we were embedding the report through the Azure AD token, I am not sure how to implement RLS through the Azure AD token, like so.

 try
            {
                var tokenData = await _authenticationHandler.GetTokenDataAsync();

                using (var client = new PowerBIClient(new Uri(_powerBiSettings.MainAddress), tokenData.tokenCredentials))
                {
                    var report = await client.Reports.GetReportAsync(_powerBiSettings.GroupId, id.ToString());
                    
                    return new ReportDetail
                    {
                        Id = Guid.Parse(report.Id),
                        Name = report.Name,
                        EmbedUrl = report.EmbedUrl,
                        AccessToken = tokenData.accessToken
                    };
                }
            }

To fix this we just imbed the power BI report token instead with RLS identity.

            try
            {
                var tokenData = await _authenticationHandler.GetTokenDataAsync();

                using (var client = new PowerBIClient(new Uri(_powerBiSettings.MainAddress), tokenData.tokenCredentials))
                {
                    var report = await client.Reports.GetReportAsync(_powerBiSettings.GroupId, id.ToString());

                    var identity = new List<EffectiveIdentity>
                    {
                        new EffectiveIdentity("MasterUser", //TODO: Change this to use azure identity
                            roles: new List<string> {"User"},
                            datasets: new List<string> {report.DatasetId})
                    };

                    var generateTokenRequestParameters = new GenerateTokenRequest("view", null, identities: identity);

                    var tokenResponse = await client.Reports.GenerateTokenInGroupAsync(_powerBiSettings.GroupId, report.Id, generateTokenRequestParameters);

                    return new ReportDetail
                    {
                        Id = Guid.Parse(report.Id),
                        Name = report.Name,
                        EmbedUrl = report.EmbedUrl,
                        AccessToken = tokenResponse.Token
                    };
                }
            }

Be sure to set the token type to embed rather than AAD token in the Javascript config.

Thanks for your help.