Authentication

OAuth is an open-standard authorization protocol that allows unlinked servers and services to provide authenticated access to data sources without sharing private credentials. It is widely used in various applications for user authentication. If you want to learn more about OAuth and the different types of credentials, refer to OAuth Authorization topic.

Snowflake authorization is slightly different compared to other providers provided by C1DataConnector. In Snowflake, the DataConnector APIs do not automatically generate OAuthAccessToken and OAuthRefreshToken. After fetching OAuthAccessToken and OAuthRefreshToken from OAuth 2.0 Playground using the OAuthClientId and OAuthClientSecret, you can complete the authentication to provide secured access to fetch data from the resource server. To connect to a Snowflake, provide the following properties:

static string OAuthClientId = @"**********";
static string OAuthClientSecret = @"*******";
static string OAuthAccessToken = @"*******";
static string OAuthRefreshToken = @"*********";
static string OAuthTokenEndpoint = "https://****.snowflakecomputing.com/oauth/token-request";

Using the OAuthClientId OAuthClientSecret OAuthRefreshToken Snowflake provider will automatically refresh the access token:

//Create connection string using C1SnowflakeConnectionStringBuilder
C1SnowflakeConnectionStringBuilder builder = new C1SnowflakeConnectionStringBuilder();
builder.Account = "****.eu-west-2.aws";
builder.Url = "https://****.eu-west-2.aws.snowflakecomputing.com";
builder.Warehouse = "****";
builder.Database = "****";
builder.Schema = "****";
builder.Role = "****";
builder.OAuthTokenEndpoint = "****.snowflakecomputing.com/oauth/token-request";
builder.OAuthClientId = "****";
builder.OAuthClientSecret = "****";
builder.OAuthRefreshToken = "****";
builder.OAuthAccessToken = "****";
//Setup Connection
using (C1SnowflakeConnectionconn = new C1SnowflakeConnection(builder))
{
    //Tried fetching data from two different tables
    C1SnowflakeCommand comm = new C1SnowflakeCommand(conn, "Select * from CALL_CENTER");
    C1SnowflakeDataAdapter adapter = new C1SnowflakeDataAdapter(comm);
    DataTable dataTable = new DataTable();
    adapter.Fill(dataTable);
    //Display fetched data
    foreach (DataRow row in dataTable.Rows)
    {
        Console.WriteLine("{0}\t{1}\t{2}", row[0], row[1], row[2]);
    }
    Console.WriteLine("Connection created and read operation completed !!!");
}

Supported Authentication methods for Snowflake provider

Snowflake supports two main authentication methods: OAuth2 authentication and Key Pair authentication.

• OAuth2 authentication involves using OAuth tokens to authenticate access to Snowflake resources. To authenticate using OAuth2, you should provide the OAuth token endpoint URL, OAuth client ID, OAuth client secret, access token, and refresh token. Additionally, you specify the URL of the Snowflake server, Snowflake account URL, warehouse name, role, database name, and schema name. This method provides a secure and standardized way to authenticate requests to Snowflake, ensuring robust security and access control.
• Key Pair authentication, on the other hand, relies on cryptographic key pairs for authentication. To authenticate using Key Pair authentication, you should provide the private key file path, fingerprint, and username used to log in to the Snowflake console. The private key file contains the generated private key, while the fingerprint can be retrieved from the Snowflake console using a specific query. This method offers a secure way to authenticate requests to Snowflake by leveraging cryptographic keys, providing enhanced security and authentication capabilities.

Connection properties used on each type of authentication

OAuth2 Authentication

1. Url: Specifies the URL of the Snowflake server.
2. Account: Specifies the Snowflake account URL.
3. Warehouse: Specifies the Snowflake warehouse name.
4. Role: Specifies the Snowflake role.
5. Database: Specifies the Snowflake database name.
6. Schema: Specifies the Snowflake schema name.
7. OAuthTokenEndpoint: Specifies the OAuth token endpoint URL for authentication.
8. OAuthClientId: Specifies the OAuth client ID for authentication.
9. OAuthClientSecret: Specifies the OAuth client secret for authentication.
10. OAuthAccessToken: Specifies the OAuth access token for authentication.
11. OAuthRefreshToken: Specifies the OAuth refresh token for authentication.

Key Pair Authentication

1. Private key: is the generated file together with a public key that contains the private key, in this property should be specified the path of the file.
2. Fingerprint: the fingerprint can be retrieved in the Snowflake console using the query ‘DESC USER username’.
3. Username: the username used to log in to the Snowflake console.