Step by Step process to create your first Blockchain Project - Hello World

[nageshcaparthy]

Blockchain…!!! This might be one of the words which is buzzing around in SAP for a long time and many developers and consultants have been waiting to explore this opportunity.  SAP Blockchain as a Service, specifically Hyperledger Fabric is now made available in the cloud foundry trial account for development and testing activities.

Note: Trial accounts or services always comes with limitations.

In this blog, you will learn the following:

1. Create SAP Cloud Foundry Trial Account


2. Navigating to your Hypderledger Fabric account


3. Creating a new instance


4. Create & Deploy chaincode


5. Create a Service Key


6. Read/Write operations using Swagger


7. Validate your read/write in Hyperledger Explorer

Before you begin, you may want to look at

• Blockchain in a nutshell


• SAP HANA Blockchain – A technical introduction

and have your trail account active.

Once you understand Blockchain, it’s now time to get started with a small example “myfirstblock” in Hyperledger Fabric service.

1. Create SAP Cloud Foundry Trail Account

• Login to trial account and click on Cloud Foundry trial

• Select Europe (Frankfurt) and click on ok.

• Your account should now be created and active for 29 days, click on Go to Space

 



 

2. Navigating to your Hypderledger Fabric account

• Click on Services and Service Marketplace

• In the list of services, search for Hyperledger Fabric and click on it

• Hyperledger Fabric – Overview with all the documentation, support information, and services plan should be listed.

3. Creating a new instance

• Click on Instances and then click on New Instance.

• Select Plan dev-beta and click on next(Dev-Beta was active for a limited period and no more active. Request you to select Dev, ignore the error message on pricing and continue with the same steps)

• Click next on Specify Parameters (optional) and Assign Application (optional). In the confirm, enter “myfirstinstance” and click on Finish

• The new instance should be created with an option such as Dashboard and Delete Instance under actions. Click on Open Dashboard

• A new tab opens up, enter your login details; same which was used during your cloud platform registration. Note: Do not use P-Number.

This is a dashboard where you can understand the Node, Peer Status, Fabric Version, Network and Create Channels.

• Now click on Channels, then click on Create Channels and enter the following details. To know more about the channels, please use the hyperlink above.

• Click on Create New Instance for the channel which was just created

• Do not modify the Service Instance name, click on Create.

• Open the service Instance Channel

• From the overview screen, click on Chaincode from the left pane (Refer to 5 Mins to kickstart your blockchain knowledge….!!! Hello World, Simplified…!!! )

4. Create & Deploy a chaincode

• Click on Deploy Code and select the “sample web.zip”.  The sample code has been shared on the link, however, to make it easy I have attached the sample code to this link. Below are the files which I have zipped as a package.

• Drag & Drop or Choose the sample web.zip file.

• Click on Deploy and you should be able to see the success message as below

• Click on “Test Chaincode” and a new window opens which is known as swagger.

5. Create a Service Key

• Go back the window Hyperledger Fabric Dashboard and click on Overview and enter the following details under “Service Keys” and click on Create Key

• Expand the key and copy the “clientId” and “clientSecret” which is required for authorization in Swagger

 

6. Read/Write operations using Swagger

• Go to Swagger tab and click on Authorize button and enter the clientId, clientSecret and authorize

Once its authorized, close the window.

• Now that we have the authorization and we are doing the first transaction to the block, we will try a POST operation, click on the POST and then click on Try it out. Enter the details as shown below and click on execute.

• You should now be able to see the response 201 as shown below

There you go, you have now successfully made your first POST operation to the blockchain.

• Now let us try to read the same data which was written to the block. Click on Get and then click on Try it out. Enter the ID “101” was used in POST operation and click on execute. You should be able to see the response as shown below.

 

7. Validate your read/write in Hyperledger Explorer

• To validate the same in a Blockchain, we use the Hyperledger Fabric Explorer. Shift to the other tab “Hyperledger Fabric Dashboard” and click on Explorer.

Here you can identify that we have totally 3 blocks created, 0 is the Genesis Block, 1 is the Chaincode deployed by us and 2 is the successful transaction from swagger.

• Click on block 2 to get the details

Alright, it’s now time to congratulate you J

#HappyLearning…!!!

Regards,

Nagesh