PartChain Ledger Abstractor

Note: This repository is still under active development! Breaking changes are possible, and we are working on improving code quality.

Ledger Abstractor Application Program Interface. This API exposes endpoints to interact with the data stored the PostgreSQL database in the PartChain ecosystem. It does not store any new information as this is done in the AEMS!

Prerequisites

• Running PostgreSQL database
• Running Keycloak

API documentation

API documentation is done via swagger. The swagger can be access for example via http://localhost:8080/api-docs/swagger/

Docker Build process

This application source code is written in Typescript, and it is using Webpack for conversion to ES5. Output ECMA Script version could be changed in ./tsconfig.json file. For more information about possible Typescript configuration options please follow this link.

$ docker build . -t [image-name]:[image-tag]

For example:

docker build  -t link-to-your-registry/laapi:feature . -f ./Dockerfile
docker push link-to-your-registry/laapi:feature

Add --build-arg HTTP_PROXY=$http_proxy --build-arg HTTPS_PROXY=$http_proxy to the build command in case you have a proxy.

Run locally

Install npm packages:

npm install

Export necessary env variables:

export API_DATABASE_PASSWORD=yourpassword
export API_DATABASE_HOST=postgresServer.com

Save keycloak.json that looks similar to this:

{
  "resource": "abstractor",
  "bearer-only": true,
  "auth-server-url": "https://auth.new.partchain.dev/auth"
}

Build project:

npm run build

Run project:

npm run serve

Access swagger at

http://localhost:8080/api-docs/swagger/

Environment variables

Variable name	Description	Default value
API_HOST	Application host name	https://domain.tld
API_BASE	API base path prefix	v0
API_PORT	Application port	8080
API_DATABASE_HOST	API database host name	https://localhost
API_DATABASE_NAME	API database name	postgres
API_DATABASE_USER	API database user	postgres
API_DATABASE_PASSWORD	API database password	password
HLF_CHILDREN_MAX_RECURSIVE_LEVEL_LIST	Count of loaded children levels for getAssetList action	2
HLF_CHILDREN_MAX_RECURSIVE_LEVEL_DETAIL	Count of loaded children levels for getAssetDetail action	2
HLF_PAGINATION_LIMIT	Count of assets per page	25
KEYCLOAK_CONFIG_PATH	Path to file with Keycloak profile	./build/development/keycloak/lion/keycloak.json

This is an excerpt of the used environmental variables. More of them and their default values can be seen in src/app/defaults.ts.

Authentication

We use keycloak JWT to authenticate against this API. As we support multiple realms for trust as a service, the keycloak.json of the API needs to look like this:

{
  "resource": "abstractor",
  "bearer-only": true,
  "auth-server-url": "https://auth.keycloak.dev/auth"
}

To identify the correct Hyperledger Fabric identity we need a field called mspid in the JWT token. For example if your fabric mspid is Lion:

 "mspid": "Lion",

We also experienced that some roles are needed by the keycloak client, for example (maybe less are needed):

"realm_access": {
        "roles": [
            "offline_access",
            "lion_user",
            "uma_authorization",
            "user"
        ]
    },

K8S Deployment process

The recommended way of deploying this service is Kubernetes. The Kubernetes deployment can be seen in the respective helm chart in the Platform Repository

License

Apache License 2.0