GraphQL API

Aidbox supports default GraphQL implementation without any extensions (specification) Queries are supported, but mutations are not.

In Aidbox UI there is a GraphiQL interface, you can try your queries there. GraphQL console sends all your requests to $graphql endpoint which you can use from your application too

GraphQL endpoint

Aidbox uses the /$graphql endpoint to serve GraphQL requests.

To make a GraphQL request send a GraphQL request object using POST method.

GraphQL request object can contain three properties:

• query — the GraphQL query to evaluate.

• operationName — the name of the operation to evaluate.

• variables — the JSON object containing variable values.

Refer to the GraphQL documentation to get more information about these properties.

Examples

Simple query

Get IDs of two Patients. This query is similar to FHIR query

GET /fhir/Patient?_count=3

Request:

POST /$graphql
content-type: text/yaml
accept: text/yaml

query: |
  query {
    PatientList(_count: 3) {
      id
    }
  }

Response:

data:
  PatientList:
    - id: patient-1
    - id: patient-2
    - id: patient-3

Query with variables

It is the same query as above but uses a variable to specify the number of results returned.

Request:

POST /$graphql
content-type: text/yaml
accept: text/yaml

query: |
  query($count: integer) {
    PatientList(_count: $count) {
      id
    }
  }
variables:
  count: 3

Response:

data:
  PatientList:
    - id: patient-1
    - id: patient-2
    - id: patient-3

Query with a timeout

You can set a timeout (in seconds) for the query.

Request:

POST /$graphql?timeout=10
content-type: text/yaml
accept: text/yaml

query: |
  query($count: integer) {
    PatientList(_count: $count) {
      id
    }
  }
variables:
  count: 3

Objects, unions, scalars

Aidbox generates an object for every known resource and non-primitive data type.

Aidbox generates a scalar for every known primitive type i.e. for every entity with type primitive.

Aidbox generates a union for every reference field. Additionally, Aidbox generates the AllResources union which contains every resource object.

Fields

Aidbox generates a field for every field in a resource. There are some special fields:

• reference fields

• revinclude fields

References

Reference fields contain all usual fields of Aidbox references (id, resourceType, display, identifier) and a special resource fields.

The resource field is an AllResource union. You can use it to fetch the referred resource using GraphQL fragments.

Example

The following query is similar to

GET /Patient?_include=organization:Organization

Request:

query {
  PatientList {
    id
    name {
      given
    }
    managingOrganization {
      id
      resource {
        ... on Organization {
          name
          id
        }
      }
    }
  }
}that

Response:

data:
  PatientList:
    - id: pt-1
      name:
        - given:
            - Patient name
      managingOrganization:
        id: org-1
        resource:
          name: Organization name
          id: org-1

Revincludes

Aidbox generates special fields to include resources that reference this resource.

Generated fields have the following name structure:

<sourceResourceType>_as_<path_to_reference>

Note: unlike FHIR revincludes, GraphQL revincludes use field path, not parameter name.

Example

The following query is similar to

GET /Organization?_revinclude=CareTeam:participant

The request:

query {
  PractitionerList {
    id
    name {
      given
    }
    careteams_as_participant_member {
      id
      name
    }
  }
}

The response:

data:
  PractitionerList:
    - id: pr-1
      name:
        - given:
            - Practitioner name
      careteams_as_participant_member:
        - id: ct-1
          name: CareTeam name

Queries

Aidbox generates three types of queries:

• get by ID,

• search,

• history.

Get by ID

Aidbox generates query with name <ResourceType>

This query accepts a single argument id and returns a resource with the specified id.

Example

The following query is similar to

GET /Patient/pt-1

Request:

query {
  Patient(id: "pt-1") {
    id
    name {
      given
    }
  }
}

Response:

data:
  Patient:
    id: pt-1
    name:
      - given:
          - Patient

History

Aidbox generates a query with the name <ResourceType>History

The query accepts id argument and return history of a resource with the specified id.

Example

The following query is similar to

GET /Practitioner/pr-1/_history

Request:

query {
  PractitionerHistory(id: "pr-1") {
    id
    name {
      given
    }
    meta {
      versionId
    }
  }
}

Response:

data:
  PractitionerHistory:
    - id: pr-1
      name:
        - given:
            - New Practitioner name
      meta:
        versionId: '11001992'
    - id: pr-1
      name:
        - given:
            - Practitioner name
      meta:
        versionId: '11001990'

Search

Aidbox generates a query with the name <ResourceType>List.

The query can accept multiple arguments. Aidbox generates arguments from search parameters.

Each search parameter leads to 2 arguments:

• <parameter> — simple argument, equivalent to using FHIR search parameter

• <parameter>_list — represents AND condition

Example

The following query is similar to

GET /Practitioner?name=another

Request

POST /$graphql
content-type: text/yaml
accept: text/yaml

query: |
  query {
    PractitionerList(name: "another") {
      id
      name {
        given
      }
    }
  }

Response

data:
  PractitionerList:
    - id: pr-2
      name:
        - given:
            - Another Practitioner name

Search with conditions

It is possible to encode simple AND and OR conditions for a single parameter.

FHIR allows to encode of the following type of conditions for a single parameter:

(A OR B OR ...) AND (C OR D OR ...) AND ...

In GraphQL API the <parameter>_list parameter represents AND condition.

E.g. PatientList(name_list: ["James", "Mary"]) searches for patients who have both names: James and Mary.

Comma represents OR condition.

E.g. PatientList(name: "James,Mary") searches for patients who have either the name James or Mary

You can use both conditions at the same time.

E.g. PatientList(name_list: ["James,Mary", "Robert,Patricia"]) searches for patients who have name James or Mary and name Robert or Patricia.

Search total

Aidbox generates a special field total_ that contains the total count of the matching result. When you use this field, Aidbox can make a query to calculate total, which can be slow (depending on data).

Example

Request:

query: |
  query {
    PatientList(_count: 2) {
      id
      name {
        given
      }
      total_
    }
  }

Response:

data:
  PatientList:
    - id: pt-1
      name:
        - given:
            - Patient name
      total_: 10000
    - id: pt-2
      name:
        - given:
            - Another Patient name
      total_: 10000

Complex examples

Multiple fragments

Get id of the DeviceRequestList resource, and add the address of the Organizations and Practitioners referenced in DeviceRequestList.requester:

query {
  DeviceRequestList {
    id,
    requester {
      resourceType
      resource {
        ... on Organization {
          id,
          address {
            use
          }
        }
        ... on Practitioner {
          id,
          address {
            use
          }
        }
      }
    }
  }
}

Common fragment

This example demonstrates how to use fragments, both types of search parameter arguments and reverse includes.

Request

fragment PractitionerRoleWithPractitioner on PractitionerRole {
  id
  code {
    coding {
      code
      system
      display
    }
  }
  practitioner {
    resource {
      ... on Practitioner {
        id
        name {
          given
        }
      }
    }
  }
}
{
  PatientList(active: true, identifier_list: [\"tenantId|org1\", \"mrn|5678\"]) {
    id
    name {
      given
    }
    generalPractitioner {
      resource {
        ...PractitionerRoleWithPractitioner
      }
    }
    observations_as_subject {
      id
      code {
        coding {
          code
          system
          display
        }
      }
      performer {
        resource {
          ...PractitionerRoleWithPractitioner
        }
      }
    }
  }
}

Response

{
  "data" : {
    "PatientList" : [ {
      "id" : "51f507b5-8723-4dda-bee6-d3cbd86da28f",
      "name" : [ {
        "given" : [ "Tom" ]
      } ],
      "generalPractitioner" : [ {
        "resource" : {
          "id" : "54513486-7b9c-4baf-84b6-8d1bdb279ba3",
          "code" : [ {
            "coding" : [ {
              "code" : "therapist",
              "system" : "sys",
              "display" : "Therapist"
            } ]
          } ],
          "practitioner" : {
            "resource" : {
              "id" : "0091e1ee-8a5b-45a1-a1be-c2638e6ed482",
              "name" : [ {
                "given" : [ "Doc" ]
              } ]
            }
          }
        }
      } ],
      "observations_as_subject" : [ {
        "id" : "68100e43-4d1c-4fb7-b4d9-2f14d359fe90",
        "code" : {
          "coding" : [ {
            "code" : "15074-8",
            "system" : "http://loinc.org",
            "display" : "Glucose"
          } ]
        },
        "performer" : [ {
          "resource" : {
            "id" : "54513486-7b9c-4baf-84b6-8d1bdb279ba3",
            "code" : [ {
              "coding" : [ {
                "code" : "therapist",
                "system" : "sys",
                "display" : "Therapist"
              } ]
            } ],
            "practitioner" : {
              "resource" : {
                "id" : "0091e1ee-8a5b-45a1-a1be-c2638e6ed482",
                "name" : [ {
                  "given" : [ "Doc" ]
                } ]
              }
            }
          }
        } ]
      } ]
    } ]
  }
}

Configuration

Set timeout

Sets the timeout for GraphQL queries in seconds. Default value is 60.

BOX_FEATURES_GRAPHQL_TIMEOUT=<integer>

Warmup

By default, Aidbox does an in-memory index cache warmup when the first request comes in.

You can change it to warmup cache on startup.

BOX_FEATURES_GRAPHQL_WARMUP__ON__STARTUP=true

Revincludes with any type

For the sake of performance, Aidbox does not provide revincludes for references of type Reference(Any), e.g. for Task.for.

When this feature is enabled, schema generation will take 2 minutes (approximately), Until the schema is generated GraphQL requests will wait.

You can enable them using the following environment variable:

BOX_FEATURES_GRAPHQL_REFERENCE__ANY=true

Enable access control in GraphQL

By default, if the POST /$graphql request passes request, it can query every resource without access control checks.

To enable access control, set the environmental variable:

BOX_FEATURES_GRAPHQL_ACCESS__CONTROL=rest-search

Under the hood, GraphQL uses Search API. You can create AccessPolicies for GET requests.

To allow Client my-client to query the request

query { PatientList(_count: 1) { id } }

the AccessPolicy which allows GET /Patient is required.

PUT /AccessPolicy/my-client-allow-patient
Content-Type: text/yaml
Accept: text/yaml

link:
  - id: my-client
    resourceType: Client
engine: matcho
matcho:
  request-method: get
  uri: /Patient

Of course, any AccessPolicy engine can be used. For example, using sql engine to allow the request if organization_id in the JWT is the same as Patient.managingOrganization:

PUT /AccessPolicy/my-client-allow-patient
Content-Type: text/yaml
Accept: text/yaml

sql:
  query: |
    SELECT resource->'managingOrganization'
    @> jsonb_build_object('resourceType', 'Organization', 'id',
    {{jwt.organization_id}}::text) FROM patient
    WHERE id = {{params._id}};
engine: sql
resourceType: AccessPolicy