baseid-transport

Transport-layer abstractions for BaseID credential exchange. Provides injectable, async transport traits for HTTP, DIDComm message delivery, BLE proximity presentation (ISO 18013-5), and NFC contactless exchange. All traits are designed for dependency injection so tests can swap in mock implementations without hitting real networks.

Key Features

• HttpClient Trait — Async HTTP with get_json, post_form, post_json, post_json_bearer, and raw request methods
• ReqwestHttpClient — Production backend powered by reqwest (enabled via http-reqwest feature flag)
• MockHttpClient — Configurable mock for testing with on_get(url, response) and on_post(url, response) builders
• DIDCommTransport — Send packed DIDComm messages to service endpoints; HttpDIDCommTransport for HTTP delivery
• BleTransport — ISO 18013-5 proximity presentation with Peripheral/Central roles, device engagement, and chunked data transfer
• NfcTransport — Contactless exchange via NDEF records or ISO 7816 APDU commands

Quick Start

use baseid_transport::{HttpClient, MockHttpClient};
use serde_json::json;

// Production: use ReqwestHttpClient
#[cfg(feature = "http-reqwest")]
let client = baseid_transport::ReqwestHttpClient::new();

// Testing: use MockHttpClient with pre-configured responses
let client = MockHttpClient::new()
    .on_get(
        "https://issuer.example.com/.well-known/openid-credential-issuer",
        json!({"credential_issuer": "https://issuer.example.com"}),
    )
    .on_post(
        "https://issuer.example.com/token",
        json!({"access_token": "tok_123", "token_type": "bearer"}),
    );

// Protocol crates accept `impl HttpClient`
let metadata = client.get_json(
    "https://issuer.example.com/.well-known/openid-credential-issuer"
).await?;

HTTP Client

The HttpClient trait is used by OID4VCI, OID4VP, SIOPv2, and DID resolution:

Method	Description
get_json(url)	GET request, parse JSON response
post_form(url, params)	POST with form-encoded body, parse JSON
post_json(url, body)	POST with JSON body (no auth)
post_json_bearer(url, body, token)	POST with JSON body and Bearer token
get(url)	Raw GET returning HttpResponse
post_raw(url, body, content_type)	Raw POST with bytes body

DIDComm Transport

Deliver packed DIDComm messages to service endpoints:

use baseid_transport::didcomm::{HttpDIDCommTransport, DIDCommTransport};

let transport = HttpDIDCommTransport::new(client);
let receipt = transport.send_message(
    "https://agent.example.com/didcomm",
    packed_message_bytes,
).await?;
// receipt.status == 202, receipt.message_id extracted from JWM

BLE Transport (ISO 18013-5)

Proximity-based credential presentation over Bluetooth Low Energy:

use baseid_transport::ble::*;

let mut transport = MockBleTransport::new();
let engagement = BleEngagement {
    service_uuid: "0000abcd-0000-1000-8000-00805f9b34fb".to_string(),
    role: BleRole::Peripheral,
    engagement_bytes: device_engagement_cbor,
};

transport.start(&engagement).await?;
transport.send(b"mdoc-request").await?;
let response = transport.receive().await?;
transport.disconnect().await?;

NFC Transport

Contactless exchange via NDEF records or ISO 7816 APDU:

use baseid_transport::nfc::*;

let transport = MockNfcTransport::new();

// NDEF mode: write/read records
transport.write_ndef(&NdefRecord {
    record_type: "U".to_string(),
    payload: b"https://issuer.example.com/offer".to_vec(),
}).await?;

// APDU mode: ISO 7816 command/response
let cmd = ApduCommand { cla: 0x00, ins: 0xA4, p1: 0x04, p2: 0x00,
    data: vec![0xA0, 0x00, 0x00, 0x02, 0x48, 0x04, 0x00], le: 0 };
let resp = transport.transceive_apdu(&cmd).await?;
assert!(resp.is_success()); // SW1=0x90, SW2=0x00

Feature Flags

Feature	Default	Description
http-reqwest	Yes	Enables ReqwestHttpClient production backend

Key Types

Type	Description
HttpClient	Async HTTP trait for all protocol network requests
ReqwestHttpClient	Production HTTP client backed by reqwest
MockHttpClient	Test mock with on_get/on_post response configuration
HttpResponse	Status, headers, body with json(), text(), is_success()
DIDCommTransport	Trait for DIDComm message delivery and receive
HttpDIDCommTransport	HTTP-based DIDComm delivery (application/didcomm-encrypted+json)
BleTransport	Trait for BLE proximity exchange (start, send, receive, disconnect)
BleEngagement	Device engagement with service UUID, role, and CBOR bytes
NfcTransport	Trait for NFC exchange (NDEF read/write, APDU transceive)
MockBleTransport	Test BLE transport with queue_incoming/sent_data
MockNfcTransport	Test NFC transport with queue_ndef/queue_apdu_response

Related Crates

• baseid-oid4vci — Uses HttpClient for issuer metadata discovery and token exchange
• baseid-didcomm — Message packing/signing, delivered via DIDCommTransport
• baseid-siop — Uses HttpClient for cross-device direct_post flow
• baseid-did — DID resolution over HTTP