Struct DemographicsService

pub struct DemographicsService<S> { /* private fields */ }

Service for managing patient demographics operations.

Uses type-state pattern to enforce correct usage at compile time. Generic parameter S is either Uninitialised or Initialised.

This service handles creation, updates, and listing of patient demographic records. All operations are version-controlled via Git repositories in each patient’s directory.

Implementations

impl DemographicsService<Uninitialised>

pub fn new(cfg: Arc<CoreConfig>) -> Self

Creates a new demographics service in the uninitialised state.

Arguments

• cfg - Core configuration containing patient data directory paths

impl DemographicsService<Uninitialised>

pub fn initialise( self, author: Author, care_location: NonEmptyText, ) -> PatientResult<DemographicsService<Initialised>>

Initialises a new patient demographics record.

Creates a new patient with a unique UUID, stores the initial demographics in a YAML file within a sharded directory structure, and initialises a Git repository for version control.

This method consumes self and returns a new DemographicsService<Initialised> on success, enforcing at compile time that you cannot call initialise() twice on the same service.

Arguments

• author - Author information for the initial Git commit
• care_location - High-level organisational location for the commit (e.g., hospital name)

Returns

Returns DemographicsService<Initialised> containing the newly created demographics record. Use demographics_id() to get the UUID.

Errors

Returns PatientError if:

• YAML serialisation of patient data fails
• Patient directory cannot be created
• patient.yaml file cannot be written
• Git repository initialisation or commit fails
• Cleanup of a partially-created record directory fails (PatientError::CleanupAfterInitialiseFailed)

Safety & Rollback

If any operation fails during initialisation, this method attempts to clean up the partially-created patient directory. If cleanup also fails, a PatientError::CleanupAfterInitialiseFailed is returned with details of both errors.

impl DemographicsService<Initialised>

pub fn with_id( cfg: Arc<CoreConfig>, demographics_id: &str, ) -> PatientResult<Self>

Creates a demographics service for an existing record.

Use this when you already have a demographics record and want to perform operations on it, such as updating demographics or listing patients.

Arguments

• cfg - Core configuration containing patient data directory paths
• demographics_id - UUID string of the existing demographics record

pub fn demographics_id(&self) -> &ShardableUuid

Returns the demographics UUID.

impl DemographicsService<Initialised>

pub fn update( &self, given_names: Vec<NonEmptyText>, last_name: &str, birth_date: &str, ) -> PatientResult<()>

Updates the demographics of an existing patient.

Reads the existing patient YAML file, updates the name and birth date fields, and writes the changes back to the file. This operation does not create a new Git commit—callers must commit changes separately if needed.

Arguments

• given_names - Vector of given names for the patient
• last_name - Family/last name of the patient
• birth_date - Birth date of the patient as a string

Errors

Returns PatientError if:

• patient.yaml file cannot be read, deserialised, serialised, or written

impl<S> DemographicsService<S>

pub fn list_patients(&self) -> Vec<Patient>

Lists all patient records from the file system.

Traverses the sharded directory structure under patient_data/demographics/ and reads all patient.yaml files to reconstruct patient records.

Returns

Vector of protobuf Patient messages containing all found patient records. Individual patient files that cannot be parsed are logged as warnings and skipped.

Directory Structure

Expects patients stored in:

<patient_data_dir>/demographics/<s1>/<s2>/<uuid>/patient.yaml

where s1/s2 are the first four hex characters of the UUID.

Trait Implementations

impl<S: Clone> Clone for DemographicsService<S>

fn clone(&self) -> DemographicsService<S>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<S: Debug> Debug for DemographicsService<S>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.