dgraph-schema

A schema for the sustainability dashboard

This repository keeps the schema and the constants for ZHAW's sustainanbility dashboard.

It is used to create a helper container for installing and/or updating the database.

Sample Data

The following sample data is suggested to use for testing:

• plain_pubs (sampledata/plain_pubs.graphql) - minimal set as it would be produced from an OAI extraction
• pubs_and_persons (sampledata/pubs_and_persons.graphql) - fully qualified example data

Run from docker compose

The following compose file will tear up a dgraph standalone instance and then install the schema and constants. Because SAMPLE_DATA is set, it will also inject the plain_pubs sample data into the database.

services:
  db:
    hostname: dgraph_standalone
    image: dgraph/standalone:v22.0.2
    restart: 'no'
    ports:
      - '8080:8080'
      - '9080:9080'

  db_init:
    image: ghcr.io/sustainability-zhaw/dgraph-schema:sha-d2daeec
    restart: 'no'
    environment:
      DGRAPH_SERVER: http://dgraph_standalone:8080
      SAMPLE_DATA: plain_pubs

db_init terminates after completing the entrypoint script. This allows one to use the database through the exposed hosts.

Example queries

Dgraph exposes two querying endpoints:

• /graphql - for graphQL queries
• /query - for dgraph DQL queries

dgraph's native RATEL UI supports only DQL queries.

Example queries are found in the examples folder. Any query file that ends on dql is a DQL query and needs be forwarded to the /query endpoint. Query files that ends on graphql or gql is a GraphQL query and has to be submitted to the /graphql endpoint.

The following example uses the examples/getsdg.graphql file with the following contents:

query {
    querySdg() {
        id
        objectsAggregate {
            count
        }
    }
}

This query is executed with the following curl command. The Content-Type-header is required as dgraph has no automatic content type detection. Note that -s is just for ommitting curl's progress bar.

curl -s \
     -X POST http://localhost:8080/graphql \
     -H 'Content-Type: application/graphql' \
     --data-binary '@examples/getsdg.graphql' 

In order to verify data only, the use of jq is recommended. To extract just the data portion of the previous example use:

curl -s \
     -X POST http://localhost:8080/graphql \
     -H 'Content-Type: application/graphql' \
     --data-binary '@examples/getsdg.graphql' \
     | jq .data