Hermes Extended API

Additional querying capabilities which consists of both REST and GraphQL APIs.

Getting Started

Install dependencies

npm install

Run development

npm start

The extended API should now be running on port 3000

Testing

Run tests

npm run dev:test

Run linting

npm run dev:lint

Production

Build

npm run build

Run compiled server code

npm run start:server

Clean build

npm dev:clean

Usage (REST)

GET endpoints exist for basic fetching of various data collections including assets, events and bundles.

Examples:

Get asset

curl -X GET http://localhost:3000/asset/<assetId>

Get assets

curl -X GET http://localhost:3000/asset 

Get event

curl -X GET http://localhost:3000/event/<eventId>

Get events

curl -X GET http://localhost:3000/event 

For a full list of endpoints see the Postman collection

Pagination

Result sets contain next and previous object pointers which allow navigation through the result set. To navigate to the next page send either pointers and the result set will begin from that position. If both pointers are sent, the next pointer will take precendence. 'hasNext' and 'hasPrevious' indicate whether or not there is additional data in either direction.

Example

{
    "results": [
        ...
    ]
    "previous": "WzE1Mzk5NjM3ODIseyIkdW5kZWZpbmVkIjp0cnVlfV0",
    "hasPrevious": false,
    "next": "WzE1Mzk5NTU0MTkseyIkdW5kZWZpbmVkIjp0cnVlfV0",
    "hasNext": true
}

Filtering data

Querying (filtering) can be achieved by sending a POST request containing a valid query object.

The query object has the following format:

{
    "query": [{
        "field": "",
        "value": "",
        "operator": ""
    },
    ],
    "limit": 0,
    "previous": ""
    "next": ""
    }

Explanation:

The field key corresponds to a field in the database and can be targeted using dot notation. For example 'metadata.bundleId' and 'content.data.unit'.

The value key is used to filter the supplied field and can contain an array, dict or primitive.

The operator key specifies how the field should be queried against the value.

The following operators are supported:

The inrange operator expects a value in the following format:

{
    "field": "content.idData.timestamp",
    "value": {"greater-than-equal": 1538315311, "less-than-equal": 1540216111},
    "operator": "inrange"
}

Query Examples:

Querying an event of type, created gte to a timestamp

curl -X POST http://localhost:3000/event/query \
  -H 'Content-Type: application/json' \
  -d '{
    "query": [{
        "field": "content.data.type",
        "value": "ambrosus.asset.info",
        "operator": "equal"
    },
    {
        "field": "content.idData.timestamp",
        "value": 1535723311,
        "operator": "greater-than-equal"
    }]
}

Querying events not of a type, for a list of assets

curl -X POST http://localhost:3000/event/query \
  -H 'Content-Type: application/json' \
  -d '{
    "query": [{
        "field": "content.data.type",
        "value": [
            "ambrosus.asset.info", "ambrosus.asset.branding"
            ],
        "operator": "not-equal"
    },
    {
        "field": "content.idData.assetId",
        "value": [
            "0x7dca2776fad2ee828b2fbc5d51951b1a8d95d8fa83593e692e95dfed084c5691", "0xf0e2333a01d75a71a6e944a602b11d8f2399c2f57070be3131a869cb0b5e1d97"
            ],
        "operator": "equal"
    }]
}

Querying events for assets not created by a user

curl -X POST http://localhost:3000/event/query \
  -H 'Content-Type: application/json' \
  -d '{
    "query": [{
        "field": "content.idData.assetId",
        "value": [
            "0x7dca2776fad2ee828b2fbc5d51951b1a8d95d8fa83593e692e95dfed084c5691", "0xf0e2333a01d75a71a6e944a602b11d8f2399c2f57070be3131a869cb0b5e1d97"
            ],
        "operator": "equal"
    },
    {
        "field": "content.idData.createdBy",
        "value": "0x38E80315167c5367A56993A6accB58c81B3A81df",
        "operator": "not-equal"
    }]
}

Aggregation

A special endpoint exists to perform limited aggregation of events grouped by assetId. The endpoint exists to fetch the latest asset event of a certain type.

Examples:

curl -X POST http://localhost:3000/event/latest/type \
  -H 'Content-Type: application/json' \
  -d '{
    "assets": ["0x9d8c8bb6101751b583e64002ad8abe681aa61b6f8179ccef668fce91798e3018", "0x2be15879ad66636da6a5cccc70d75cda65809113f50355d97c93296d67486913"],
    "type": "ambrosus.asset.info"
}

Analytics

The following summations are available for all data collections. Time serious data is TBD

Examples:

Count all events

curl -X GET  http://localhost:3000/event/count 

Count of events created month to date

curl -X GET  http://localhost:3000/event/mtd

For a full list of endpoints see the Postman collection

Usage (GraphQL)

In browser IDE:

http://localhost:3000/graphiql

GraphQL Endpoint:

http://localhost:3000/gql

Angular support:

https://www.apollographql.com/docs/angular/

Examples:

Get events

curl -X POST http://localhost:3000/gql \
  -H 'Content-Type: application/json' \
  -d '{
"query": "{
    getEvents {
        results {
            eventId
            content {
                signature
                idData {
                    assetId
                    createdBy
                    accessLevel
                    timestamp
                } 
            }
        }
        hasNext
        next
        hasPrevious
        previous
    }
}",
"variables": null,
"operationName": null
}'

Get events, limiting results

curl -X POST http://localhost:3000/gql \
  -H 'Content-Type: application/json' \
  -d '{
"query": "{
    getEvents {
        results {
            eventId
            content {
                idData {
                    assetId
                } 
            }
        }
        hasNext
        next
    }
}",
"variables": null,
"operationName": null
}'