# Issue Credential v2.1 - issue multiple credentials of same type

### Challenges
- `credential_preview` & ~~`credentialSubject`~~
- single `V20CredExRecord` - multiple `cred_request` and `cred_issue` messages
### From RFC



## Changes proposed
- add `issue_multiple` to `cred_request` message
- ~~Add `multiple_credentials` bool property and `attach_ids_handled` sequence property to `V20CredExRecord`. Issuer uses `attach_id` to track which credentials are left for issuance. Holder uses this when storing credential. Optionally, holder can also use `attach_id` to send subsequent `cred_request` [in the sequence] with updated `cred_preview`.~~
- For indy credentials or when Holder doesn't initiate from request, exchange of multiple`cred_issue` & `cred_request` messages is not necessary

### Indy

"formats": [
    {
        "attach_id": "indy#0",
        "format": "hlindy/cred-abstract@v2.0"
    },
    {
        "attach_id": "indy#1",
        "format": "hlindy/cred-abstract@v2.0"
    }
],
"multiple_available": true,
"credential_preview": {
    "@type": "did:sov:BzCbsNYhMrjHiqZDTUASHg;spec/issue-credential/2.0/credential-preview",
    "attributes": {
        "indy#0": [
            {
                "name": "testA",
                "value": "testA"
            }
        ],
        "indy#1": [
            {
                "name": "testB",
                "value": "testB"
            }
        ]
}
}

### W3C

Not valid - as W3C credentials are missing cred_preview

"formats": [
    {
        "attach_id": "ld_proof#0",
        "format": "aries/ld-proof-vc-detail@v1.0"
    },
    {
        "attach_id": "ld_proof#1",
        "format": "aries/ld-proof-vc-detail@v1.0"
    }
],
"multiple_available": true,
"filter": {
    "ld_proof": {
        "credential": {
            "@context": [
                "https://www.w3.org/2018/credentials/v1",
                "https://w3id.org/citizenship/v1",
                "https://w3id.org/security/bbs/v1",
            ],
            "type": [
                "VerifiableCredential",
                "PermanentResident",
            ],
            "id": "https://credential.example.com/residents/1234567890",
            "issuer": self.did,
            "issuanceDate": "2020-01-01T12:00:00Z",
            "credentialSubject": {
                "ld_proof#0": {
                    "type": [
                        "PermanentResident"
                    ],
                    "givenName": "ALICE",
                    "familyName": "SMITH",
                    "gender": "Female",
                    "birthCountry": "Bahamas",
                    "birthDate": "1958-07-17"
                },
                "ld_proof#1": {
                    "type": [
                        "PermanentResident"
                    ],
                    "givenName": "BOB",
                    "familyName": "SMITH",
                    "gender": "Male",
                    "birthCountry": "Bahamas",
                    "birthDate": "1968-07-17"
                }
            },
        },
        "options": {
            "proofType": SIG_TYPE_BLS
        },
    }
}