OpenSRP / FHIR-Core Export¶

TRICC can export draw.io clinical decision support diagrams to a full FHIR R4 bundle compatible with OpenSRP 2 / FHIR-Core.

Overview¶

The OpenSRPStrategy extends the base FHIRStrategy and produces:

Quick Start¶

```bash

Convert a draw.io file to OpenSRP FHIR-Core output¶

python tests/build.py \ -i tests/data/demo.drawio \ -o tests/output/opensrp/ \ -O OpenSRPStrategy \ -d my_form_id ```

Output directory layout¶

tests/output/opensrp/ ├── questionnaire/ │ └── Questionnaire-<process>.json ├── library/ │ ├── Library-<form_id>-<process>.json │ └── Library-<form_id>Helper.json ├── structure-map/ │ └── StructureMap-<process>.json ├── ValueSet/ │ └── ValueSet-<node_id>.json ├── plan-definition/ │ └── PlanDefinition-<process>.json ├── binary/ │ ├── Binary-config.json │ └── Binary-<node_id>.json # images ├── Composition.json └── fsh/ ├── Questionnaire-<process>.fsh ├── Library-<form_id>-<process>.fsh ├── PlanDefinition-<process>.fsh ├── Composition.fsh └── ...

Architecture¶

Class hierarchy¶

BaseOutPutStrategy └── FHIRStrategy (standard FHIR SDC — Questionnaire, Library, StructureMap, ValueSet, Binary) └── OpenSRPStrategy (adds PlanDefinition, Composition, Binary config, FSH, openSRP wiring)

Processing pipeline¶

execute() ├── process_base() → generate_base(node) builds Questionnaire items ├── process_relevance() → generate_relevance(node) adds enableWhenExpression (FHIRPath) ├── process_calculate() → generate_calculate(node) adds CQL defines + calculatedExpression ├── process_export() → generate_export(node) builds StructureMap rules └── export() ├── [FHIRStrategy] write questionnaire/, library/, structure-map/, ValueSet/, binary/ └── [OpenSRPStrategy] ├── generate_plandefinition(process) → plan-definition/ ├── _wire_questionnaire_extensions() → cqlInputResources + planDefinitions on Q ├── generate_composition() → Composition.json ├── generate_binary_config() → binary/Binary-config.json └── _write_fsh_files() → fsh/

cpg-common-process Mapping¶

Each draw.io activity is mapped to a cpg-common-process named event via the process attribute on TriccNodeMainStart.

The get_process(node) function (in tricc_oo/visitors/tricc.py) walks the TRICC graph upward to find the process name for any node:

1. If the node itself is a TriccNodeMainStart → return node.process
2. If the node's activity root is a TriccNodeMainStart → return root.process
3. Recurse on the activity
4. Fallback: walk prev_nodes

Supported process names (from tricc_oo/visitors/utils.py):

registration, triage, clinical-assessment, determine-diagnosis, guideline-based-care, dispense-medications, discharge-referral-of-patient, record-and-report, monitor-and-follow-up-of-patient, alert-reminder-education-of-patient, guideline-based-care, dispense-medications, discharge-referral-of-patient, record-and-report, monitor-and-follow-up-of-patient

Expression System¶

Relevance (enableWhen)¶

Relevance conditions from the TRICC graph are converted to FHIRPath using convert_expression_to_fhirpath() and attached as an SDC enableWhenExpression extension:

json { "url": "http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-enableWhenExpression", "valueExpression": { "language": "text/fhirpath", "expression": "%resource.item.where(linkId='age').answer.value >= 18" } }

Calculations (calculatedExpression / initialExpression)¶

Calculate nodes (and some relevance logic) are converted to CQL using convert_expression_to_cql(). A shared Helper library provides data access via FHIR resources (e.g. GetObsValue("concept.code")). Per-process libraries are thin wrappers that expose named defines.

In the Questionnaire, expressions use simple define names (the Questionnaire declares its library/libraries at the top level):

json { "url": "http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-calculatedExpression", "valueExpression": { "language": "text/cql-identifier", "expression": "Calc_bmi" } }

Example generated CQL style (segment library):

```cql include fhir_formHelper version '1.0.0' called Helper

define Calc_bmi: Helper.GetObsValue("weight") / (Helper.GetObsValue("height") * Helper.GetObsValue("height")) ```

PlanDefinition¶

Each cpg-common-process gets a PlanDefinition with:

• trigger: named-event → cpg-common-process-<process>
• condition: CQL applicability expression "Is Applicable"
• action: definitionCanonical pointing to the Questionnaire

json { "resourceType": "PlanDefinition", "id": "pd-registration", "status": "active", "trigger": [{ "type": "named-event", "name": "cpg-common-process-registration" }], "action": [{ "title": "Fill registration form", "definitionCanonical": "http://example.org/Questionnaire/registration", "condition": [{ "kind": "applicability", "expression": { "language": "text/cql", "expression": "Is Applicable" } }] }] }

Questionnaire Extensions (openSRP wiring)¶

The _wire_questionnaire_extensions() method adds two openSRP-specific extensions to each Questionnaire:

cqlInputResources¶

Points to the CQL Library for this process:

json { "url": "http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-launchContext", "extension": [ { "url": "name", "valueId": "<form_id>-<process>" }, { "url": "type", "valueCode": "Library" } ] }

planDefinitions¶

References the PlanDefinition for this process:

json { "url": "http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-planDefinition", "valueCanonical": "http://example.org/PlanDefinition/pd-<process>" }

StructureMap (Extraction)¶

Each node with a concept attribute generates a StructureMap rule that extracts the answer into the appropriate FHIR resource:

FSH Output¶

All resources are also serialized to FHIR Shorthand (FSH) in the fsh/ subdirectory, ready for compilation with SUSHI.

The FSH serializer (tricc_oo/converters/fhir/fsh_serializer.py) supports:

• Questionnaire → Instance: … InstanceOf: SDCQuestionnaireExtract
• Library → Instance: … InstanceOf: Library
• StructureMap → Instance: … InstanceOf: StructureMap
• ValueSet → ValueSet: … with concept includes
• PlanDefinition → Instance: … InstanceOf: PlanDefinition
• Composition → Instance: … InstanceOf: Composition
• Binary → Instance: … InstanceOf: Binary
• Any other resource type → generic Instance with JSON comments

Testing¶

```bash

Run all strategy tests¶

python -m pytest tests/test_strategies/ -v

Run a specific test class¶

python -m pytest tests/test_strategies/test_opensrp_strategy.py::TestFshSerializer -v

Full integration test (requires a draw.io file)¶

python tests/build.py \ -i tests/data/demo.drawio \ -o tests/output/opensrp/ \ -O OpenSRPStrategy \ -l d ```

Key Files¶

References¶

• FHIR R4 Specification
• SDC Implementation Guide
• CPG Implementation Guide
• OpenSRP FHIR-Core Documentation
• FHIR Shorthand (FSH)
• SUSHI Compiler