Merge pull request #2 from decentralised-dataexchange/features/4-Upda…

…te-README.md-file

Fix #4: Update README.md file

README.md

@@ -17,28 +17,75 @@
 
 ## About
 
-This repository is created to align the iOS implementation of digital wallets across the EWC LSP consortium wallet providers. This also ensures all wallets providers can self-test and sign off against the EWC Interoperability Test Bed (ITB). 
+This repository is created to align the implementation of digital wallets across the EWC LSP consortium wallet providers. This also ensures all wallets providers can self-test and sign off against the EWC Interoperability Test Bed (ITB). 
 
 ## Contributing
 
 Feel free to improve the plugin and send us a pull request. If you find any problems, please create an issue in this repo. Wallet providers can raise a PR once they have implemented and aligned with the RFCs. 
 
 ## Usage
 
-### Requirements
-Environment
-iOS 10.0+,
-macOS 10.10+,
+### Download
 
-Swift 4.2 and Xcode 10.
+eudi-wallet-oidc-ios is available through SPM. To install it, simply add the following spm repository url  https://github.com/decentralised-dataexchange/eudi-wallet-oidc-ios to your project package dependencies.
 
-### Download and Install
+### Functions available
+#### 1. DIDService
+
+| Function | Return Type | Description |
+| -------- | -------- | ------- |
+| createJWK() | [String: Any]? | Generate JWK of curve P-256 for an optional seed value. |
+| createDID(jwk: [String: Any]) | String | Generate a did:key:jcs-pub decentralised identifier. |
+
+#### 2. IssueService
+
+| Function | Return Type | Description |
+| -------- | -------- | ------- |
+| resolveCredentialOffer(data: String?) | CredentialOffer | To process the credential offer request |
+| processAuthorisationRequest(did: String, privateKey: P256.Signing.PrivateKey, credentialOffer: CredentialOffer, codeVerifier: String, authServer: AuthorisationServerWellKnownConfiguration) | String? | This API requests to grant access to the credential endpoint. Returns URL with short lived authorisation code in query parameter |
+| processTokenRequest(authServerWellKnownConfig: AuthorisationServerWellKnownConfiguration, code: String, did: String, privateKey: P256.Signing.PrivateKey, codeVerifier: String, isPreAuthorisedCodeFlow: Bool, preAuthCode: String, userPin: String?) | TokenResponse | To obtain the access token |
+| processCredentialRequest(did: String, privateKey: P256.Signing.PrivateKey, credentialOffer: CredentialOffer, credentialEndpointUrlString: String, c_nonce: String, accessToken: String) | CredentialResponse | To obtain the credential |
+| processDeferredCredentialRequest(acceptanceToken: String, deferredCredentialEndPoint: String) | CredentialResponse | To obtain the credential issued in a deferred manner. |
+
+#### 3. VerificationService
+
+| Function | Return Type | Description |
+| -------- | -------- | ------- |
+| processAuthorisationRequest(data: String?) | PresentationRequest? | Authorisation requests can be presented to the wallet by verifying in two ways: 1) by value 2) by reference as defined in JWT-Secured Authorization Request (JAR) via use of response_uri. The custom URL scheme for authorisation requests is openid4vp://. |
+| sendVPToken(did: String, privateKey: P256.Signing.PrivateKey, presentationRequest: PresentationRequest?, credentialsList: [String]?) | Data? | Authorisation response is sent by constructing the vp_token and presentation_submission values. |
+
+#### 4. DiscoveryService
+
+| Function | Return Type | Description |
+| -------- | -------- | ------- |
+| getIssuerConfig(credentialIssuerWellKnownURI: String?) | IssuerWellKnownConfiguration? | To resolve the well-known endpoint for the credential issuer |
+| getAuthConfig(authorisationServerWellKnownURI:String?) | AuthorisationServerWellKnownConfiguration? | To resolve the well-known endpoint for the authorisation server |
+
+#### 5. CodeVerifierService
+
+| Function | Return Type | Description |
+| -------- | -------- | ------- |
+| generateCodeVerifier() | String? | To create code verifier (https://datatracker.ietf.org/doc/html/rfc7636#section-4.1) |
+| generateCodeChallenge(codeVerifier: String) | String? | To generate code challenge from the code verifier (https://datatracker.ietf.org/doc/html/rfc7636#section-4.2) |
 
-TBD
 
 ### How to use in your application
 
-TBD
+#### Issuance
+Refer the [Issue Verifiable Credential RFC](https://github.com/EWC-consortium/eudi-wallet-rfcs/blob/main/ewc-rfc001-issue-verifiable-credential.md) for issuance flow. 
+
+* The credential issuance can be an authorisation flow or a pre-authorised one. 
+* The credential offer can be obtained from QR code or Deeplink. Make use of `resolveCredentialOffer` for processing the credential offer
+* Perform the Discovery to get the Issuer config and Autherisation server config. Use `getIssuerConfig` and `getAuthConfig` for it.
+* If the credential issuance is authorisaation flow then call the `processAuthorisationRequest` and then `processTokenRequest` using the code received 
+* If the credential issuance is pre-authorised, the call `processTokenRequest`, show PIN entering screen and pass the PIN in the token request if PIN required in the `Credential Offer`
+* Fetch credential using the `processCredentialRequest`, in response we get the credential. If the response contains `acceptanceToken`, then poll `processDeferredCredentialRequest` unitll the credential is received.
+
+#### Verification
+Refer the [Present Verifiable Credentials RFC](https://github.com/EWC-consortium/eudi-wallet-rfcs/blob/main/ewc-rfc001-issue-verifiable-credential.md) for Verification flow.
+
+* The presentation request can be obtained fromQR code or Deeplink. Make use of `processAuthorisationRequest` for processing the presentationRequest.
+* Use `sendVPToken` for verification.
 
 ## Licensing