Batching Certificate

Batching Certificates

OpenCerts is able to batch large number of certificates to be issued on the Ethereum blockchain in a single transaction.

To facilitate the ease of signing and batching OpenCerts, a npm package and a CLI tool is provided.



OpenCerts Data File

To follow through this section, please have all the certificates generated from the previous step in a single folder.

CLI Tool

Installing the CLI Tool

Clone the certificate-cli source code repository to your deployment environment

git clone

Navigate into the directory

cd certificate-cli

Install the dependencies for the package

npm install –production –ignore-scripts

Using the CLI Tool

Place the unsigned certificates into a folder

mkdir unsigned_certs mv <path/certs> unsigned_certs

Run the CLI Tool to batch the certificates

node index.js batch unsigned_certs signed_certs

Sample output:

2018-08-30T05:06:55.313Z info: Batch Certificate Root: 70250f22ecaa7c12cdde4a4bc6dc3bf2464433691cd462bcfe980d7e85f6a06c

Upon successful batching of the certificates, the merkle root for the entire batch will be printed and the signed certificates will be found in the folder signed_certs.

Note the merkle root, it will be published onto the certficate store in later steps.

NPM Package

For the documentations for writing custom application to process the certificates, refer to the documentation for OpenCerts