Enum ContentType 

pub enum ContentType {
    Csv,
    CsvWithHeader,
    Json,
    NdJson,
    Parquet,
}

Supported output content types for ViewDefinition transformations.

This enum defines the available output formats for transformed FHIR data. Each format has specific characteristics and use cases for different integration scenarios.

Format Descriptions

• CSV: Comma-separated values without headers
• CSV with Headers: Comma-separated values with column headers
• JSON: Pretty-printed JSON array of objects
• NDJSON: Newline-delimited JSON (one object per line)
• Parquet: Apache Parquet columnar format (planned)

Examples

use helios_sof::ContentType;

// Parse from string
let csv_type = ContentType::from_string("text/csv")?;
assert_eq!(csv_type, ContentType::CsvWithHeader);  // Default includes headers

let json_type = ContentType::from_string("application/json")?;
assert_eq!(json_type, ContentType::Json);

// CSV without headers
let csv_no_headers = ContentType::from_string("text/csv;header=false")?;
assert_eq!(csv_no_headers, ContentType::Csv);

Variants

Csv

Comma-separated values format without headers

CsvWithHeader

Comma-separated values format with column headers

Json

Pretty-printed JSON array format

NdJson

Newline-delimited JSON format (NDJSON)

Parquet

Apache Parquet columnar format (not yet implemented)

Implementations

impl ContentType

pub fn from_string(s: &str) -> Result<Self, SofError>

Parse a content type from its MIME type string representation.

This method converts standard MIME type strings to the corresponding ContentType enum variants. It supports the SQL-on-FHIR specification’s recommended content types.

Supported MIME Types

• "text/csv" → ContentType::Csv
• "text/csv" → ContentType::CsvWithHeader (default: headers included)
• "text/csv;header=true" → ContentType::CsvWithHeader
• "text/csv;header=false" → ContentType::Csv
• "application/json" → ContentType::Json
• "application/ndjson" → ContentType::NdJson
• "application/parquet" → ContentType::Parquet

Arguments

• s - The MIME type string to parse

Returns

• Ok(ContentType) - Successfully parsed content type
• Err(SofError::UnsupportedContentType) - Unknown or unsupported MIME type

Examples

use helios_sof::ContentType;

// Shortened format names
let csv = ContentType::from_string("csv")?;
assert_eq!(csv, ContentType::CsvWithHeader);

let json = ContentType::from_string("json")?;
assert_eq!(json, ContentType::Json);

let ndjson = ContentType::from_string("ndjson")?;
assert_eq!(ndjson, ContentType::NdJson);

// Full MIME types still supported
let csv_mime = ContentType::from_string("text/csv")?;
assert_eq!(csv_mime, ContentType::CsvWithHeader);

// CSV with headers explicitly
let csv_headers = ContentType::from_string("text/csv;header=true")?;
assert_eq!(csv_headers, ContentType::CsvWithHeader);

// CSV without headers
let csv_no_headers = ContentType::from_string("text/csv;header=false")?;
assert_eq!(csv_no_headers, ContentType::Csv);

// JSON format
let json_mime = ContentType::from_string("application/json")?;
assert_eq!(json_mime, ContentType::Json);

// Error for unsupported type
assert!(ContentType::from_string("text/plain").is_err());

Trait Implementations

impl Clone for ContentType

fn clone(&self) -> ContentType

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ContentType

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

Formats the value using the given formatter.

impl PartialEq for ContentType

fn eq(&self, other: &ContentType) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for ContentType

impl Eq for ContentType

impl StructuralPartialEq for ContentType