Using objects instead of Array in Fhir Identities and other related date structures

[ashfahan]

Using objects instead of array can provide us serval improvements in code. i.e having Record<string, T> where T is the payload object type

like instead of using this code team?.identifier?.find((e) => e.use === 'official')?.value we can simply use team?.identifier?.official?.value

which array can we change (i only noticed these in code)

• Identifier
• Human Name

which will

• improve our code readability
• no need to loop over array thus decreasing code complexity.

we can use this function like this to convert array into object to achieve the same result

/**
 * From T, convert a set of keys to required, that arr in the union K.
 */
export type Require<T, K extends keyof T> = Omit<T, K> & Required<Pick<T, K>>;

type ProcessedObj<T> = Omit<T, 'identifier'> & {
  identifier?: Partial<Record<FhirIdentifier.UseEnum, FhirIdentifier>>;
};

export function ProcessFHIRObject<T>(
  object: T & { identifier?: FhirIdentifier[] }
): ProcessedObj<T> {
  return ({
    ...object,
    ...(object.identifier && {
      identifier: convertToObject<FhirIdentifier, FhirIdentifier.UseEnum>(object.identifier, 'use'),
    }),
  } as unknown) as ProcessedObj<T>;
}

/**
 * Convert array of Object T to object with param key used for key of resultant object.
 *
 * @param array array of T to be converted
 * @param key key of T to used to the processed Object
 * @returns resultant Object
 */
export function convertToObject<T, K extends string>(
  array: Array<T>,
  key: keyof T
): Partial<Record<K, T>> {
  return array.reduce((prev, item) => {
    const _key = item[key];
    if (typeof _key !== 'string') throw new Error('Key should be a string value');
    return { ...prev, [_key]: item };
  }, {}) as Partial<Record<K, T>>;
}

[peterMuriuki]

This sounds very reasonable but I am afraid it would not be following the spec. It would make our fhir instance not conform to the fhir spec, negating the biggest advantage of Fhir which is interoperability.