Create Course

Creating a course is the first step in setting up a learning environment on Andamio. This transaction mints a new course instance on-chain, registering the creator as the owner and first teacher, and returns a unique courseId (policy ID) used for all subsequent course operations.

Summary

Property	Value
System	Course
Role	Owner
Type Key	`course_create`
Build Endpoint	`POST /api/v2/tx/instance/owner/course/create`
DB Sync	Yes
Service Fee	100 ADA base + 10 ADA per teacher
Est. Wallet Cost	~130 ADA for 1 teacher

The service fee scales with the number of teachers: 110 ADA for 1 teacher, 120 ADA for 2, and so on. The estimated wallet cost of ~130 ADA for a single teacher breaks down as: transaction fee ~0.53 ADA + service fee 110 ADA + UTxO deposits ~19.15 ADA.

Build Transaction

Endpoint

POST /api/v2/tx/instance/owner/course/create

Request Body

{
  "alias": "courseowner",
  "teachers": ["courseowner"],
  "walletData": {
    "usedAddresses": ["addr1qx2fxv2umyhttkxyxp8x0dlpdt3k6cwng5pxj3jhsydzer3n0d3vllmyqwsx5wktcd8cc3sq835lu7drv2xwl2wywfgse35a3x"],
    "changeAddress": "addr1qx2fxv2umyhttkxyxp8x0dlpdt3k6cwng5pxj3jhsydzer3n0d3vllmyqwsx5wktcd8cc3sq835lu7drv2xwl2wywfgse35a3x"
  }
}

Field	Type	Required	Description
`alias`	`string` (Alias)	Yes	The owner's access token alias. Must already have a minted access token.
`teachers`	`string[]` (Alias[])	Yes	List of teacher aliases to include at creation. The Gateway auto-sets this to `[alias]` — the creator is always the first teacher.
`walletData`	`WalletData`	No	Object containing `usedAddresses` (string[]) and `changeAddress` (string). If omitted, the Gateway resolves wallet data from the authenticated session.

Response

{
  "unsignedTxCBOR": "84a800...",
  "courseId": "a1b2c3d4e5f6..."
}

The response includes two fields:

unsignedTxCBOR — The unsigned transaction CBOR, ready for the user's wallet to sign.
courseId — The on-chain policy ID for the new course. Save this value. It is required as a parameter for every subsequent course operation (managing teachers, managing modules, assessing assignments, etc.).

Register Transaction

After the user signs and submits the transaction, register it with the state machine:

POST /api/v2/tx/register

{
  "tx_hash": "64-char hex hash from wallet.submitTx()",
  "tx_type": "course_create",
  "instance_id": "a1b2c3d4e5f6..."
}

The owner_alias is auto-captured from the JWT — no manual metadata is needed. You may optionally include metadata fields for the database record:

Field	Type	Required	Description
`title`	`string`	No	Display title for the course
`description`	`string`	No	Course description
`image_url`	`string`	No	URL to a course image or thumbnail

On confirmation, the state machine registers the course in the database with the owner alias and on-chain courseId.

Endpoint	Description
`GET /api/v2/courses/{course_id}`	Fetch course details after creation, including owner, teachers, and module list

Example: Full Lifecycle

const API_URL = "https://api.andamio.io";

// 1. Build
const buildRes = await fetch(`${API_URL}/api/v2/tx/instance/owner/course/create`, {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "X-API-Key": API_KEY,
    "Authorization": `Bearer ${userJwt}`,
  },
  body: JSON.stringify({
    alias: "courseowner",
    teachers: ["courseowner"],
    walletData: {
      usedAddresses: [walletAddress],
      changeAddress: walletAddress,
    },
  }),
});
const { unsignedTxCBOR, courseId } = await buildRes.json();
// Save courseId — this is the on-chain policy ID for all subsequent course operations

// 2. Sign
const signedTx = await wallet.signTx(unsignedTxCBOR);

// 3. Submit
const txHash = await wallet.submitTx(signedTx);

// 4. Register
await fetch(`${API_URL}/api/v2/tx/register`, {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "X-API-Key": API_KEY,
    "Authorization": `Bearer ${userJwt}`,
  },
  body: JSON.stringify({
    tx_hash: txHash,
    tx_type: "course_create",
    instance_id: courseId,
    metadata: {
      title: "Introduction to Cardano Development",
      description: "A hands-on course covering smart contract basics",
    },
  }),
});

// 5. Monitor (SSE)
const events = new EventSource(
  `${API_URL}/api/v2/tx/stream/${txHash}`
);
events.addEventListener("state_change", (e) => {
  const data = JSON.parse(e.data);
  console.log(`State: ${data.old_state} → ${data.new_state}`);
});
events.addEventListener("complete", (e) => {
  const data = JSON.parse(e.data);
  console.log(`Final: ${data.final_state}`);
  events.close();
});