Struct Extensions 

pub struct Extensions(/* private fields */);

Undocumented JSON fields found on an OCPI object, preserved verbatim.

OCPI 2.3.0 is explicit:

An OCPI Platform SHALL NOT reject request or response payloads based on the presence of JSON object field names that are not documented in this specification.

OCPI implementers are encouraged to extend OCPI with new fields to address needs that are not foreseen by the specification.

Every OCPI object in this crate carries an extensions field marked #[serde(flatten)], so a vendor field arrives, survives, and is written back out unchanged. A hub built on this crate can therefore sit between two parties that have agreed on an extension without knowing anything about it — which is the whole point of that paragraph, and the thing generated type sets get wrong.

Keys are kept in a BTreeMap, so serialisation order is deterministic.

Every wire object in this crate carries one as a #[serde(flatten)] field, so the undocumented members of the object it came from land here and are written straight back:

use ocpi_kit::types::Extensions;

let json = r#"{"acme_note":"kerbside","nltnm_accuracy_m":3}"#;
let extensions: Extensions = serde_json::from_str(json).unwrap();

assert_eq!(extensions.get::<u32>("nltnm_accuracy_m").unwrap(), Some(3));
assert_eq!(serde_json::to_string(&extensions).unwrap(), json);

In place, on a real object:

let json = r#"{"latitude":"52.010","longitude":"4.350","nltnm_accuracy_m":3}"#;
let geo: GeoLocation = serde_json::from_str(json).unwrap();
assert_eq!(geo.extensions.get::<u32>("nltnm_accuracy_m").unwrap(), Some(3));
assert_eq!(serde_json::to_string(&geo).unwrap(), json);

Spec: 2.3.0 §transport_and_format — Non-specified JSON fields

Implementations

impl Extensions

pub fn new() -> Self

An empty set of extensions.

pub fn is_empty(&self) -> bool

Whether no undocumented field was present.

Objects skip serialising their extensions field when this is true, so an object that carried no extensions is written back byte-identically.

pub fn len(&self) -> usize

How many undocumented fields are present.

pub fn get_raw(&self, key: &str) -> Option<&Value>

The raw JSON value stored under key, if any.

pub fn get<T: DeserializeOwned>(&self, key: &str) -> Result<Option<T>, Error>

Deserialises the value stored under key into T.

Returns Ok(None) when the key is absent, and Err when it is present but does not deserialise into T.

Errors

Propagates the serde_json error describing why the value did not fit T.

pub fn insert<T: Serialize>( &mut self, key: impl Into<String>, value: T, ) -> Result<(), Error>

Stores value under key, replacing any previous value.

Errors

Propagates the serde_json error if value cannot be serialised.

pub fn remove(&mut self, key: &str) -> Option<Value>

Removes and returns the raw value stored under key.

pub fn contains_key(&self, key: &str) -> bool

Whether key is present.

pub fn iter(&self) -> impl Iterator<Item = (&String, &Value)>

The undocumented fields, in key order.

pub fn keys(&self) -> impl Iterator<Item = &String>

The field names, in order.

Trait Implementations

impl Clone for Extensions

fn clone(&self) -> Extensions

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Extensions

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

Formats the value using the given formatter.

impl Default for Extensions

fn default() -> Extensions

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Extensions

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<K: Into<String>, V: Into<Value>> FromIterator<(K, V)> for Extensions

fn from_iter<I: IntoIterator<Item = (K, V)>>(iter: I) -> Self

Creates a value from an iterator.

impl<'a> IntoIterator for &'a Extensions

type Item = (&'a String, &'a Value)

The type of the elements being iterated over.

type IntoIter = Iter<'a, String, Value>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl JsonSchema for Extensions

Available on crate feature schema only.

fn schema_name() -> Cow<'static, str>

The name of the generated JSON Schema.

fn json_schema(_g: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn inline_schema() -> bool

Whether JSON Schemas generated for this type should be included directly in parent schemas, rather than being re-used where possible using the $ref keyword.

fn schema_id() -> Cow<'static, str>

Returns a string that uniquely identifies the schema produced by this type.

impl PartialEq for Extensions

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for Extensions

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Extensions

impl Validate for Extensions

fn validate_in(&self, _v: &mut Validator)

Appends this value’s violations to v, relative to v’s current position.

fn validate(&self) -> Result<(), Violations>

Validates this value as the root of an object graph.