Alibaba Cloud Blockchain as a Service (BaaS) provides a free contract test chain so you can explore the complete blockchain workflow without setting up your own network. This guide walks you through the full onboarding sequence: applying for a Transport Layer Security (TLS) connection certificate, creating an on-chain account, deploying a smart contract using Cloud IDE, and connecting to the chain through the software development kit (SDK). By the end, you will be able to submit your first on-chain transaction and view it in the blockchain explorer.
The contract test chain is for testing only. Do not upload business code or business data. To set up your own blockchain network, see Create a consortium.
Prerequisites
Before you begin, ensure that you have:
Activated Alibaba Cloud BaaS
Logged in to Alibaba Cloud — use your Alibaba Cloud account or RAM user account
Apply for the contract test chain
Log in to the Alibaba Cloud BaaS console.
In the left-side navigation pane, click Overview under Ant Blockchain.
Click Try for Free, then fill in the pop-up form to apply.
After the application succeeds, you can perform the following operations on the contract test chain:
Apply for a TLS connection certificate
Create an on-chain account
Debug and deploy contracts
Connect to the blockchain using SDK
Apply for a TLS connection certificate
After applying for the contract test chain, the platform guides you through the TLS certificate application. Two generation methods are available: Automatically Generated (recommended) and Manually Generated.
The certificate is valid for three years. Re-apply after it expires.
Automatically Generated (recommended)
Fill in the application information and click Apply.
Download the private key and certificate.
You have only one chance to download the private key. Once you leave this page, you cannot download it again.
Manually Generated
Upload a locally generated certificate signing request (CSR) file client.csr and click Apply.
To generate client.key and client.csr on your local machine, see Generate certificates and key pairs locally.
Create an on-chain account
On the contract test chain card, click ··· in the upper-right corner, then click Create Account.
In the pop-up window, select a creation method and follow the prompts. Two methods are available: Automatically (recommended) and Manually.
Automatically (recommended)
Select Automatically and fill in the application information.
Click Apply.
Download the public-private key pair in the pop-up window. These keys are required for future application development.
You have only one chance to download the private key. Once you leave this page, you cannot download it again.
Manually
Select Manually and fill in the Account Name, Account Public Key, and Account Recovery Public Key.
Click Apply.
Use Client Tool to generate and manage public and private keys. For steps to generate key pairs locally, see Generate certificates and key pairs locally.
Debug and deploy contracts
After applying for a TLS connection certificate and creating an on-chain account, click Deploy Contract on the contract test chain card to open Cloud IDE — the platform's browser-based contract development environment. Cloud IDE supports developing, compiling, debugging, deploying, and calling contracts in multiple languages.
For detailed usage, see Use Cloud IDE.
Connect to the blockchain using SDK
On the contract test chain card, click ··· to download certificates, development components, or reset certificates.
The contract test chain has been upgraded to v2.19.4. Connect directly through Maven dependencies — no SDK download is required.
For application development guides, see Java SDK developer guide.
Blockchain explorer
After connecting to the contract test chain through the SDK and submitting an on-chain transaction, click View Details on the contract test chain card to open the blockchain explorer. The explorer displays:
Total business statistics
Network status and node details
Current block height
Transaction volumes, blocks, and transactions over time
For usage instructions, see View blockchain details.
Generate certificates and key pairs locally
If you chose Manually Generated for the TLS certificate or Manually for the account, generate the required files on your local machine using one of the following methods.
Use OpenSSL
macOS includes OpenSSL by default. No installation is required.
Install OpenSSL on Windows
Download OpenSSL version 1.0.2o (recommended):
Open a command prompt and go to the
bindirectory of the OpenSSL installation path.Set the environment variable:
set OPENSSL_CONF=openssl.cfg
Generate a certificate signing request
Run the following command to generate a private key and a certificate signing request (CSR):
Store the private key file securely and remember the passphrase.
openssl req -newkey rsa:2048 -keyout key_pkcs10.pem -out csr.pemThe command prompts for the following information:
| Field | Description | Example |
|---|---|---|
| Country name | Two-letter ISO country code | CN |
| State or province name | Full province name | Zhejiang |
| Locality name | City | Hangzhou |
| Organization name | Company name (Pinyin for Chinese companies) | YourCompany |
| Organizational unit name | Department | IT Dept |
| Common name | Domain name of the SSL-protected website | pay.example.com |
| Email address | (Optional) Contact email | — |
| Challenge password | (Optional) | — |
| Optional company name | (Optional) | — |
Use the local key service
The BaaS platform provides a Java-based local key service as an alternative to OpenSSL.
Start the local key service
Make sure Java Runtime Environment (JRE) 1.7 or later is installed.
Download baas-crypto-tool-1.0.0.jar.
Start the key service:
java -jar baas-crypto-tool-1.0.0.jar --server.port=8080
Generate a TLS certificate signing request
In a browser, go to the following URL to generate tlskey.zip:
https://localhost:8080/api/crypto/generateTlsKey?algo=rsa&isPkcs8=true&password=<your-password>Replace <your-password> with your own password.
Unzip tlskey.zip to get:
client.key— used to connect to the blockchainclient.csr— the CSR to be signed by the BaaS platform
Generate account key pairs
In a browser, go to the following URL to generate userkey.zip:
http://localhost:8080/api/crypto/generateUserKey?algo=ec&isPkcs8=true&password=<your-password>Replace <your-password> with your own password.
Unzip userkey.zip to get:
user.key— the account private keypub.txt— the account public key
Run the command twice to generate two key pairs: one for the account and one for account recovery.
What's next
After completing the free trial, continue with these resources:
Create a consortium — set up your own blockchain network for business use
Java SDK developer guide — start building your first on-chain application
Use Cloud IDE — develop and deploy smart contracts in the browser