Threema Message API

As a developer, you will find here all necessary information and source code to successfully integrate Threema Gateway in your environment. Threema does not provide a graphical user interface for Threema Gateway. The Message API is an interface that can be used from within customer-specific software to send and receive messages via Threema Gateway.

Download .NET API Tool (SDK & Documentation)

Use console client

Local operations (no network communication)

Encrypt

.\Threema.MsgApi.Console.exe -e <privateKey> <publicKey>

Encrypt standard input using the given sender private key and recipient public key. Prints two lines to standard output: first the nonce (hex), and then the box (hex).

Decrypt

.\Threema.MsgApi.Console.exe -d <privateKey> <publicKey> <nonce>

Decrypt standard input using the given recipient private key and sender public key. The nonce must be given on the command line, and the box (hex) on standard input. Prints the decrypted message to standard output.

Hash Email Address

.\Threema.MsgApi.Console.exe -h -e <email>

Hash an email address for identity lookup. Prints the hash in hex.

Hash Phone Number

.\Threema.MsgApi.Console.exe -h -p <phoneNo>

Hash a phone number for identity lookup. Prints the hash in hex.

Generate Key Pair

.\Threema.MsgApi.Console.exe -g <privateKeyFile> <publicKeyPath>

Generate a new key pair and write the private and public keys to the respective files (in hex).

Derive Public Key

.\Threema.MsgApi.Console.exe -p <privateKey>

Derive the public key that corresponds with the given private key.

Network operations

Send Simple Message

.\Threema.MsgApi.Console.exe -s <to> <from> <secret>

Send a message from standard input with server-side encryption to the given ID. 'from' is the API identity and 'secret' is the API secret. Returns the message ID on success.

Send End-to-End Encrypted Text Message

.\Threema.MsgApi.Console.exe -S <to> <from> <secret> <privateKey>

Encrypt standard input and send the message to the given ID. 'from' is the API identity and 'secret' is the API secret. Prints the message ID on success.

Send End-to-End Encrypted Image Message

.\Threema.MsgApi.Console.exe -S -i <to> <from> <secret> <privateKey> <imageFilePath>

Encrypt standard input and send the message to the given ID. 'from' is the API identity and 'secret' is the API secret. Prints the message ID on success.

Send End-to-End Encrypted File Message

.\Threema.MsgApi.Console.exe -S -f <to> <from> <secret> <privateKey> <file> [thumbnail]

Encrypt the file (and thumbnail) and send a file message to the given ID. 'from' is the API identity and 'secret' is the API secret. Prints the message ID on success.

ID Lookup By Email Address

.\Threema.MsgApi.Console.exe -l -e <email> <from> <secret>

Lookup the ID linked to the given email address (will be hashed locally).

ID Lookup By Phone Number

.\Threema.MsgApi.Console.exe -l -p <phoneNo> <from> <secret>

Lookup the ID linked to the given phone number (will be hashed locally).

Fetch Public Key

.\Threema.MsgApi.Console.exe -l -k <id> <from> <secret>

Lookup the public key for the given ID.

Fetch Capability

.\Threema.MsgApi.Console.exe -c <id> <from> <secret>

Fetch the capability of a Threema ID

Decrypt and download

.\Threema.MsgApi.Console.exe -D <id> <from> <secret> <privateKey> <messageId> <nonce> [outputFolder]

Decrypt a box (box from the stdin) message and download (if the message is a image or file message) the file(s) to the defined directory

Create a Connection


		string gatewayId = "*MYGWID1";
		string secret = "SECRET_OF_MY_GATEWAY_ID";

		//TODO: implement your own public key store, or use the
		//SQLite implementation "PublicKeyStoreDb", to get better performance.

		APIConnector apiConnector = new APIConnector(gatewayId, secret, null);
	
	

Send a Text Message to a Threema-ID (Simple Mode)


		//create the connection
		string threemaId = "ABCD1234";
		string textMessage = "Simple Mode Message";

		string messageId = apiConnector.SendTextMessage(threemaId, textMessage);
	

Send a Text Message to a Threema-ID (End-To-End Mode)


		//create the connection
		string threemaId = "ABCD1234";
		string textMessage = "Simple Mode Message";
		byte[] privateKey = DataUtils.ReadKeyFile("/path/to/my/private.key", Key.KeyType.PRIVATE);

		E2EHelper e2EHelper = new E2EHelper(apiConnector, privateKey);
		string messageId = e2EHelper.SendTextMessage(to, textMessage);
	

Send a File Message to a Threema-ID (End-To-End Mode)


		//create the connection
		string threemaId = "ABCD1234";
		string textMessage = "Simple Mode Message";
		byte[] privateKey = DataUtils.ReadKeyFile("/path/to/my/private.key", Key.KeyType.PRIVATE);
		FileInfo fileToSend = new FileInfo("/path/to/my/pdf.pdf");
		FileInfo thumbnailFileToSend = new FileInfo("/path/to/my/pdf-thumbnail.jpg");

		E2EHelper e2EHelper = new E2EHelper(apiConnector, privateKey);
		string messageId = e2EHelper.SendFileMessage(to, fileToSend, thumbnailFileToSend);