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Converting CQL to a library

This document discusses how to convert a CQL script to a FHIR library.

Android FHIR SDK CQL Builder

SDK workflow testing module has which can do translation from a CQL to Library resource. This automatically does the elm conversion for you internally.

An example usage can be seen in tests found here

val library = CqlBuilder.compileAndBuild(cqlScriptInputStream)

FHIR Core CQL Testing Module

The fhir-resources repository has a testing module which allows to not only get the complete Library resource to directly save to the server but also allows to test the output and make changes on the fly. Check the cucumber tests Feature File, the Test Code File and the Convertor Util Method

FHIR Core Tooling Library

FHIR Core tooling library can also be used to get a Library by running the command below. Details on the tool can be found here.

fct convert -t cql -i /some/path/Patient-1.0.0.cql

Unrecommended conversion methods

These are other methods to convert a CQL script to elm+json.


The below approaches output a json-elm which then needs to be Base64 decoded and copied to the Library content as Attachment.

CQL to ELM REST Translator

A elm REST app that can be used to run elm microservice and convert CQL via a REST API.

CQL to ELM JAVA Translator

Her is an elm java app that can be used as an elm translator on related files and get an output. Instructions can be found here