openEHR Workflow

Where oehrpy fits in the openEHR data lifecycle — from clinical modelling to querying patient data. Phases highlighted in blue are handled by oehrpy.

Phase 1 Modelling Outside oehrpy

Archetype Designer

Define archetypes & templates using clinical modelling tools (e.g. Better Archetype Designer)

Export .opt

Export an Operational Template (.opt) file from the modelling tool

Phase 2 CDR Upload Outside oehrpy

Upload Template

Upload the .opt to your CDR (e.g. EHRBase) via its admin API

Web Template

CDR generates a Web Template with FLAT paths and constraints

oehrpy scope

Phase 3 App Development oehrpy

Parse OPT

Parse .opt files with OPTParser to extract template metadata

Fetch Web Template

Get Web Template JSON from CDR with get_web_template() for FLAT paths (ADR-0005)

Generate Builder

Generate metadata-only builder skeletons with BuilderGenerator; FLAT paths from Web Template

Validate Template

Validate OPT files against RM spec using OPTValidator

Validate Composition

Catch FLAT path errors before submission with FlatValidator

Phase 4 Write Composition oehrpy

Template Builder

Construct compositions with type-safe builders (e.g. VitalSignsBuilder)

FLAT Format

Build FLAT compositions with FlatBuilder using dot-separated paths

Canonical JSON

Serialize RM objects to openEHR canonical JSON with _type fields

Submit to CDR

Send compositions via EHRBaseClient async REST client

Phase 5 Read / Query oehrpy

AQL Builder

Build type-safe AQL queries with AqlBuilder fluent API

Execute Query

Run AQL queries against the CDR via EHRBaseClient

Deserialize

Parse query results back into typed RM objects for processing

Format Reference

.opt Operational Template — XML file exported from modelling tools

Web Template CDR-generated JSON with FLAT paths and constraints

FLAT Dot-separated paths like bp:0/systolic|magnitude

Canonical JSON Hierarchical JSON with _type discriminator fields

AQL Archetype Query Language for retrieving clinical data

RM Reference Model — 134 Pydantic classes for openEHR 1.1.0

oehrpy scope (Phases 3–5)

External tools (Phases 1–2)