73 lines
2.0 KiB
Markdown
73 lines
2.0 KiB
Markdown
# Helper routines to manage DIDs/VC/VPs
|
|
|
|
This module is a wrapper around the functions exported by SpruceID's `DIDKit` framework.
|
|
|
|
## DID generation and storage
|
|
|
|
For now DIDs are of the kind `did:key`, with planned support for `did:web` in the near future.
|
|
|
|
Creation of a DID involves two steps:
|
|
* Generate a unique DID controller key
|
|
* Derive a `did:key` type from the key
|
|
|
|
Both must be stored in the IdHub database and linked to a `User` for later retrieval.
|
|
|
|
```python
|
|
# Use case: generate and link a new DID for an existing user
|
|
user = request.user # ...
|
|
|
|
controller_key = idhub_ssikit.generate_did_controller_key()
|
|
did_string = idhub_ssikit.keydid_from_controller_key(controller_key)
|
|
|
|
|
|
did = idhub.models.DID(
|
|
did = did_string,
|
|
user = user
|
|
)
|
|
did_controller_key = idhub.models.DIDControllerKey(
|
|
key_material = controller_key,
|
|
owner_did = did
|
|
)
|
|
|
|
did.save()
|
|
did_controller_key.save()
|
|
```
|
|
|
|
## Verifiable Credential issuance
|
|
|
|
Verifiable Credential templates are stored as Jinja2 (TBD) templates in `/schemas` folder. Please examine each template to see what data must be passed to it in order to render.
|
|
|
|
The data passed to the template must at a minimum include:
|
|
* issuer_did
|
|
* subject_did
|
|
* vc_id
|
|
|
|
For example, in order to render `/schemas/member-credential.json`:
|
|
|
|
```python
|
|
from jinja2 import Environment, FileSystemLoader, select_autoescape
|
|
import idhub_ssikit
|
|
|
|
env = Environment(
|
|
loader=FileSystemLoader("vc_templates"),
|
|
autoescape=select_autoescape()
|
|
)
|
|
unsigned_vc_template = env.get_template("member-credential.json")
|
|
|
|
issuer_user = request.user
|
|
issuer_did = user.dids[0] # TODO: Django ORM pseudocode
|
|
issuer_did_controller_key = did.keys[0] # TODO: Django ORM pseudocode
|
|
|
|
data = {
|
|
"vc_id": "http://pangea.org/credentials/3731",
|
|
"issuer_did": issuer_did,
|
|
"subject_did": "did:web:[...]",
|
|
"issuance_date": "2020-08-19T21:41:50Z",
|
|
"subject_is_member_of": "Pangea"
|
|
}
|
|
signed_credential = idhub_ssikit.render_and_sign_credential(
|
|
unsigned_vc_template,
|
|
issuer_did_controller_key,
|
|
data
|
|
)
|
|
``` |