sqnc-hyproof-api

Description

An API service for issuing hydrogen certificates using the Sequence (SQNC) ledger-based infrastructure

Configuration

Use a .env at root of the repository to set values for the environment variables defined in .env file.

	required	default	description
PORT	N	3000	The port for the API to listen on
LOG_LEVEL	N	debug	Logging level. Valid values are [trace, debug, info, warn, error, fatal]
DB_PORT	N	5432	The port for the database
DB_HOST	Y	-	The database hostname / host
DB_NAME	N	sqnc-hyproof-api	The database name
DB_USERNAME	Y	-	The database username
DB_PASSWORD	Y	-	The database password
IDENTITY_SERVICE_HOST	Y	-	Hostname of the sqnc-identity-service
IDENTITY_SERVICE_PORT	N	3000	Port of the sqnc-identity-service
NODE_HOST	Y	-	The hostname of the sqnc-node the API should connect to
NODE_PORT	N	9944	The port of the sqnc-node the API should connect to
LOG_LEVEL	N	info	Logging level. Valid values are [trace, debug, info, warn, error, fatal]
USER_URI	Y	-	The Substrate URI representing the private key to use when making sqnc-node transactions
IPFS_HOST	Y	-	Hostname of the IPFS node to use for metadata storage
IPFS_PORT	N	5001	Port of the IPFS node to use for metadata storage
WATCHER_POLL_PERIOD_MS	N	10000	Number of ms between polling of service state
WATCHER_TIMEOUT_MS	N	2000	Timeout period in ms for service state
API_SWAGGER_BG_COLOR	N	#fafafa	CSS color val for UI bg ( try: e4f2f3 , e7f6e6 or f8dddd
API_SWAGGER_TITLE	N	API	String used to customise the title of the html page
API_SWAGGER_HEADING	N	ApiService	String used to customise the H2 heading
ENVIRONMENT_VAR	N	example	An environment specific variable ( not in use )

Getting started

# start dependencies
docker compose up -d
# install packages
npm i
# run migrations
npm run db:migrate
# put process flows on-chain
npm run flows
# start service in dev mode. In order to start in full - npm start"
npm run dev

View OpenAPI documentation for all routes with Swagger:

localhost:3000/swagger/

Database

before performing any database interactions like clean/migrate make sure you have database running e.g. docker-compose up -d or any local instance if not using docker

# running migrations
npm run db:migrate

# creating new migration
## install npx globally
npm i -g knex
## make new migration with some prefixes
npx knex migrate:make --knexfile src/lib/db/knexfile.ts attachment-table

Tests

Unit tests are executed by calling:

npm run test:unit

Integration tests require the test dependency services be brought up using docker:

# start dependencies
docker compose -f ./docker-compose-test.yml up -d
# install packages
npm ci
# run migrations
npm run db:migrate
# put process flows on-chain
npm run flows

Integration tests are then executed by calling:

npm run test

Process Flows

To ensure integrity of data within transactions (and therefore on chain), it's possible to define custom processes that validate transactions. More info.

Process flows covering this API's transactions are in processFlows.json. The file is an array of process flows that can be supplied to the sqnc-process-management CLI for creating processes on chain:

npm run flows

API design

sqnc-hyproof-api provides a RESTful OpenAPI-based interface for third parties and front-ends to interact with the Sequence (SQNC) system. The design prioritises:

1. RESTful design principles:
   • all endpoints describing discrete operations on path derived entities.
   • use of HTTP verbs to describe whether state is modified, whether the action is idempotent etc.
   • HTTP response codes indicating the correct status of the request.
   • HTTP response bodies including the details of a query response or details about the entity being created/modified.
2. Simplicity of structure. The API should be easily understood by a third party and traversable.
3. Simplicity of usage:
   • all APIs that take request bodies taking a JSON structured request with the exception of attachment upload (which is idiomatically represented as a multipart form).
   • all APIs which return a body returning a JSON structured response (again with the exception of attachments.
4. Abstraction of the underlying DLT components. This means no token Ids, no block numbers etc.
5. Conflict free identifiers. All identifiers must be conflict free as updates can come from third party organisations.

Fundamental entities

This is project is primary based on two entities in regards to the API.

Certificate - that can be issued, initiated and revoked by a regulator. This is something we will keep circulating around Attachments - file or json information that is stored on IPFS service Transaction - records representing interactions with the chain

Running locally

running with docker-compose -f docker-compose-3-persona.yml logs -f will render all logs, also can be parsed by | grep.

docker-compose -f docker-compose-3-persona.yml logs -f | grep regulator

single persona Run docker compose up -d to start the required dependencies to fully demo sqnc-hyproof-api.

multiple persona Run docker-compose -f docker-compose-3-persona.yml up to start the required dependencies to fully demo sqnc-hyproof-api.

services

• sqnc-hyproof-api (+ PostgreSQL)
• sqnc-identity-service (+ PostgreSQL)
• ipfs
• sqnc-node

You can run a full 3-party demonstration using docker-compose -f docker-compose-3-persona.yml up --build -d.

Identities

The 3-party demonstration creates 3 personas with different roles, given below. Their Swagger API endpoints can be accessed using:

Heidi (the Hydrogen Producer):

• localhost:8000/swagger

• localhost:9000/v1/swagger

Emma (the Energy Provider):

• localhost:8010/swagger

• localhost:9010/v1/swagger

Reginald (the Regulator):

• localhost:8020/swagger

• localhost:9020/v1/swagger

The single-party version only uses:

• HyProof API: localhost:3000/swagger

• Identity Service: localhost:3002/v1/swagger

Using the HyProof API

You can find a basic cli walk-through for using the API in scripts/basic-demo.md or alternatively, you can view more details in the digicatapult/sqnc-documentation repository ( in the ./docs/hyproof/ folder ).

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