Credential issuance is the process of creating and signing a verifiable credential using the Truvera API. Verifiable Credentials are cryptographically secure and tamper-proof. They cannot be edited once issued, but they can be revoked and replaced with a new credential.
By default, the Truvera API issues a credential to a holder wallet without storing a copy—only credential metadata is stored. If the holder does not yet have a wallet, we recommend provisioning a cloud wallet for that holder and issuing the credential into it. If that is not appropriate for your use case, you can choose to persist the credential, in which case we will encrypt and store the credential for later retrieval using a password.
The following metadata is stored on each issuance:
- Credential ID property
- Credential size in bytes
- Issuer DID
- Issuance date
Creates and issues a JSON-LD verifiable credential that conforms to the W3C VCDM specification. The type values and subject properties must be represented by a schema URI in the context property. If you do not specify a context property, the API will automatically generate an embedded JSON-LD context based on the properties within your credential. You can read more about JSON-LD and contexts here.
{% hint style="info" %}
The https://www.w3.org/2018/credentials/v1 context URI is always required and will be supplied by default at all times as mandated by the spec. If you pass a custom context, you must ensure that you define all the required JSON-LD terms. Please also note that the request format here is not the same as an issued verifiable credential. You can issue to multiple subjects per credential by passing an array of objects.
{% endhint %}
To sign a credential, an issuer must be supplied as either a fully qualified DID string or an object with at least an id property which is a fully qualified DID. (e.g: did:dock:xyz)
{% hint style="warning" %}
The issuer property must be a DID that you control with your Truvera account.
{% endhint %}
As mentioned in the development tips, you can create an example payload in Truvera Workspace by:
- Open the browser's dev tools
- Look at the network requests
- Manually issue a credential with the desired schema from the desired issuer profile
- In the section that shows HTTP headers, you can copy the Request URL ("Headers" in Google Chrome)
- In the section that shows the request preview, you can copy the text of the request (in Google Chrome, click on "Preview", then right-click on the top-level element "{,...}" and select "Copy object")
Truvera credentials support anonymous credentials using Zero Knowledge Proofs and Selective Disclosure by using the BBS2023 signing algorithm when issuing the credential. To enable this functionality, simply set the algorithm field in the request to dockbbs.
As mentioned above, issued credentials are not stored and so should be issue directly into a holder wallet. Truvera's API has built in credential distribution on issuance, allowing you to send credentials directly to a holder's email and/or Truvera-compatible wallet. You can achieve this by supplying the recipientEmail field and distribute: true in your request. For DID distribution, simply set the credentialSubject.id property to the holder's DID.
In some use cases, you might choose to set the persist value to true and provide a password string which will store the credential contents encrypted on our platform.
In order to support revocation the credential must be linked to a revocation registry at the time of issuance. To link the revocation registry to the credential set the status field in the Credential body to the registry.id value.
{% hint style="info" %} One time use credentials can be created, but automating the revocation based on tracking the verification of the credential ID and revoking the credential associated with it. {% endhint %}
An expiration date can be set when issuing a credential making the credential invalid after the assigned time. To check the expiration date for Zero Knowledge Proof credentials (using the dockbbs algorythm) the expiration date needs to be requested in the verification template otherwise due to the nature of zero knowledge proof it will not be disclosed automatically.
At the moment it is not possible to add a file to the credential itself. If a credential has to have a file associated with it, the file will need to be placed in public storage and the link to that location and a hash of the content should be added to the attributes of the credential.
{% openapi src="https://swagger-api.truvera.io/openapi.yaml" path="/credentials" method="post" %} https://swagger-api.truvera.io/openapi.yaml {% endopenapi %}
When you issue a credential with us, persistent or not, we will store certain metadata about the credential to make it easier for you to reference. You can pull a list of credential metadata using this route. To return the content of a persisted credential, you should use the GET /credentials/{id} route.
{% openapi src="https://swagger-api.truvera.io/openapi.yaml" path="/credentials" method="get" %} https://swagger-api.truvera.io/openapi.yaml {% endopenapi %}
When a credential has been persisted on our systems, you can fetch the credential data by supplying a credential ID and the password used at issuance to encrypt the credential.
{% openapi src="https://swagger-api.truvera.io/openapi.yaml" path="/credentials/{id}" method="get" %} https://swagger-api.truvera.io/openapi.yaml {% endopenapi %}
Creates a request to gather certain claims and then issues the holder a credential after submission. The claims are user provided and type is based on the schema provided. This can be useful to catch a subject's DID without knowing it beforehand, name or other field. It should only be used when you do not already know this data or cannot find it by other means. There is a risk that a user may enter false data - so use it sparingly and not for fields that are important.
Typically, once the request has been created, you would show the holder the QR URL as an image or deep link for them to scan with a wallet and enter claims. After the holder submits the requested information the credential is automatically issued.
{% openapi src="https://swagger-api.truvera.io/openapi.yaml" path="/credentials/request-claims" method="post" %} https://swagger-api.truvera.io/openapi.yaml {% endopenapi %}
Lists all created request claims that are open (the holders have not submitted the requested information).
{% openapi src="../.gitbook/assets/openapi (1).yaml" path="/credentials/request-claims" method="get" %} openapi (1).yaml {% endopenapi %}
A credential can have its metadata deleted, and if persisted the contents will also be deleted. Deleting a credential will remove any reference to it and its contents from our systems. This action cannot be undone. This action will not revoke or invalidate the credential in any way.
{% openapi src="https://swagger-api.truvera.io/openapi.yaml" path="/credentials/{id}" method="delete" %} https://swagger-api.truvera.io/openapi.yaml {% endopenapi %}