Authenticate

The authenticate function is the foundation of the Truvideo SDK. It securely initiates a session and prepares the SDK for capturing, uploading, and editing media.

This guide will walk you through integrating authentication into your project using the Truvideo Core Module.

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Authentication Integration Guide

Prerequisites

Before you begin:

• Make sure the Core module is integrated. See iOS Integration Guide »

• Request your API Key and Secret Key from Truvideo.

Get the API key and Secret Key from Truvideo Support

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Step-by-Step Authentication Flow

Step 1: Prepare Your Credentials

Ensure you have:

• API Key

• Secret Key

• External Id (If provided)

These are needed to sign each authentication request securely.

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Step 2: Generate a Secure Signature

The SDK requires a hashed signature to validate each request. Follow this process to generate one:

1. Build the Payload

   • Use TruvideoSdk.generatePayload() to create a dynamic payload string.

2. Sign the Payload

   • Hash the payload using HMAC-SHA256 with your Secret Key.

3. Encode the Signature

   • Convert the hash into a hexadecimal string or base64 format.

4. Send the Signature

   • Include the signature in your authentication request.

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Swift: HMAC-SHA256 Utility

Use the following Swift extension to generate the signature:

import Foundation
import CommonCrypto

extension String {
    /// Generates an HMAC-SHA256 hash using a secret key.
    func toSha256String(using key: String) -> String {
        let hmac256 = CCHmacAlgorithm(kCCHmacAlgSHA256)
        var macData = Data(count: Int(CC_SHA256_DIGEST_LENGTH))

        key.withCString { keyCString in
            withCString { msgCString in
                macData.withUnsafeMutableBytes { macDataBytes in
                    guard let keyBytes = UnsafeRawPointer(keyCString)?.assumingMemoryBound(to: UInt8.self),
                          let msgBytes = UnsafeRawPointer(msgCString)?.assumingMemoryBound(to: UInt8.self) else {
                        return
                    }

                    CCHmac(
                        hmac256,
                        keyBytes, Int(strlen(keyCString)),
                        msgBytes, Int(strlen(msgCString)),
                        macDataBytes.bindMemory(to: UInt8.self).baseAddress
                    )
                }
            }
        }

        return macData.map { String(format: "%02x", $0) }.joined()
    }
}

Step 3: Authenticate with the SDK

Now, use the authenticate() method to start the session.

func authenticate() async {
        let isAuthenticated = TruvideoSdk.isAuthenticated
        let isAuthenticationExpired = TruvideoSdk.isAuthenticationExpired
        
        let apiKey = "your-api-key" 
        let secretKey = "your-secret-key"
        do {
            let  payload = try TruvideoSdk.generatePayload()
            
            /// The payload string is transformed into an encrypted string using the SHA256 algorithm.
            let signature = payload.toSha256String(using: secretKey)
            if try isAuthenticated() || isAuthenticationExpired() {
                ///   Initialize a session when the user is not authenticated.
                /// - Parameters:
                ///     - API_Key : Provided by TruVideo team
                ///     - Payload : generated by sdk TruvideoSdk.generatePayload() every time you have to create new payload
                ///     - Signature: encrypted string payload using the SHA256 algorithm with "secret key"
                ///     - Secret_Key: secret key is also provided by TruVideo team
                try await TruvideoSdk.authenticate(
                    apiKey: apiKey, 
                    payload: payload, 
                    signature: signature
                )
            }
            
            /// Initialize a session when the user is already authenticated.
            try await TruvideoSdk.initAuthentication()
        } catch {
            print("Error")
        }
}

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Final Steps: Test Your Integration

After implementing the authentication:

• Run your application to verify that the SDK session initializes successfully.

• Monitor the logs for any issues related to signatures or tokens.

• Once confirmed, proceed to explore media capture, uploading, and editing features.

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Thank you for using the Truvideo SDK. You're now authenticated and ready to explore all features!