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Change policies

In the previous step, we observed that the approval process for subjects in France only requires approval from WFO. However, in Spain, the procedure is different. Although both WFO and SFO have sufficient authority to approve the organic certification without the intervention of the other entity, our governance policies do not allow this. Both entities must approve a new event request for it to be considered accepted or rejected.

Therefore, in this section of the tutorial, we propose updating the governance policies so that wine-related subjects only need approval from one of the two mentioned entities.

Let’s start by checking the current policies in the governance before making these changes:

{
    "policies": [
        {
            "approve": {
                "quorum": "MAJORITY"
            },
            "evaluate": {
                "quorum": "MAJORITY"
            },
            "id": "governance",
            "validate": {
                "quorum": "MAJORITY"
            }
        },
        {
            "approve": {
                "quorum": "MAJORITY"
            },
            "evaluate": {
                "quorum": "MAJORITY"
            },
            "id": "Wine",
            "validate": {
                "quorum": "MAJORITY"
            }
        }
    ]
}

We will make the necessary change in the policies for the Wine subjects:

{
    "policies": [
        {
            "approve": {
                "quorum": "MAJORITY"
            },
            "evaluate": {
                "quorum": "MAJORITY"
            },
            "id": "governance",
            "validate": {
                "quorum": "MAJORITY"
            }
        },
        {
            "approve": {
                "quorum": "MAJORITY"
            },
            "evaluate": {
                "quorum": "MAJORITY"
            },
            "id": "Wine",
            "validate": {
                "quorum": {
                    "FIXED": 1
                }
            }
        }
    ]
}

To generate these changes, we will use our tool kore-Patch following this procedure:

kore-patch '{"policies":[{"approve":{"quorum":"MAJORITY"},"evaluate":{"quorum":"MAJORITY"},"id":"governance","validate":{"quorum":"MAJORITY"}},{"approve":{"quorum":"MAJORITY"},"evaluate":{"quorum":"MAJORITY"},"id":"Wine","validate":{"quorum":"MAJORITY"}}]}' '{"policies":[{"approve":{"quorum":"MAJORITY"},"evaluate":{"quorum":"MAJORITY"},"id":"governance","validate":{"quorum":"MAJORITY"}},{"approve":{"quorum":"MAJORITY"},"evaluate":{"quorum":"MAJORITY"},"id":"Wine","validate":{"quorum":{"FIXED":1}}}]}'

The result obtained will be:

[
    {
        "op": "replace",
        "path": "/policies/1/validate/quorum",
        "value": {
        "FIXED": 1
        }
    }
]

Next, we will invoke the governance contract method responsible for updating its properties:

curl --request POST 'http://localhost:3000/event-requests' \
--header 'Content-Type: application/json' \
--data-raw '{
    "request": {
        "Fact": {
            "subject_id": {{GOVERNANCE-ID}},
            "payload": {
                "Patch": {
                    "data": [
                        {
                            "op": "replace",
                            "path": "/policies/1/approve/quorum",
                            "value": {
                                "FIXED": 1
                            }
                        }
                    ]
                }
            }
        }
    }
}'

Once we have sent the governance update request, we should receive the approval request again. To do this, run the following command:

curl --request GET 'http://localhost:3000/approval-requests?status=Pending'

Copy the value of the id field, but this time, approval from WFO will also be necessary. Therefore, we will perform the following two actions:

curl --request PATCH 'http://localhost:3000/approval-requests/{{PREVIUS-ID}}' \
--header 'Content-Type: application/json' \
--data-raw '{"state": "RespondedAccepted"}'

curl --request PATCH 'http://localhost:3002/approval-requests/{{PREVIUS-ID}}' \
--header 'Content-Type: application/json' \
--data-raw '{"state": "RespondedAccepted"}'

If everything went well, when you execute the following command, the governance sn should be 8, and the changes made earlier should be displayed:

curl --request GET 'http://localhost:3000/subjects/{{GOVERNANCE-ID}}'

Now, let’s create a new wine bottle subject in Spain to test our change:

curl --request POST 'http://localhost:3001/event-requests' \
--header 'Content-Type: application/json' \
--data-raw '{
    "request": {
        "Create": {
        "governance_id": "{{GOVERNANCE-ID}}",
        "schema_id": "Wine",
        "namespace": "Spain",
        "name": "Wine"
        }
    }
}'

When you perform this action, you will receive a request-id, which you should copy and use in the following command:

curl --request GET 'http://localhost:3001/event-requests/{{REQUEST-ID}}/state'

This last command will give you a response similar to the following:

{
    "id": "{{REQUEST-ID}}",
    "subject_id": "{{SUBJECT-ID}}",
    "sn": 0,
    "state": "finished",
    "success": true
}

Before we can issue a certification event, we need to initialize the bottle. To do this, execute the following command:

curl --request POST 'http://localhost:3001/event-requests' \
--header 'Content-Type: application/json' \
--data-raw '{
    "request": {
        "Fact": {
            "subject_id": {{SUBJECT-ID}},
            "payload": {
                "Init": {
                    "harvest": 3,
                    "grape": "PinotNoir",
                    "origin": "spain"
                }
            }
        }
    }
}'

When you query the subject, it should have a sn value of 1 and display the previously mentioned information:

curl --request GET 'http://localhost:3001/subjects/{{SUBJECT-ID}}'

{
    "subject_id": "{{SUBJECT-ID}}",
    "governance_id": "{{GOVERNANCE-ID}}",
    "sn": 1,
    "public_key": "E5DkRaljajwUZ1HrpgdkIxdTu0fbrg-nqoBJFHqm6GJY",
    "namespace": "Spain",
    "name": "Wine",
    "schema_id": "Wine",
    "owner": "{{CONTROLLER-ID}}",
    "creator": "{{CONTROLLER-ID}}",
    "properties": {
        "grape": "PinotNoir",
        "harvest": 3,
        "organic_certified": null,
        "origin": "spain",
        "temperature_control": {
            "last_check": 0,
            "temperature_ok": true
        }
    },
    "active": true
}

Now, we will test issuing the certification event. To do this, we will generate the event signature we want to issue using kore-Sign, with the following format, replacing subject_id with the identifier of our Wine subject:

kore-sign 'f855c6736463a65f515afe7b85d1418c096ed73852b42bbe4c332eb43d532326' '{"Fact":{"subject_id":"{{SUBJECT-ID}}","payload":{"OrganicCertification":{"fertilizers_control":false,"pesticides_control":false,"analytics":false,"additional_info":"test"}}}}'

The result of this execution will be included in the following request:

curl --request POST 'http://localhost:3001/event-requests' \
--header 'Content-Type: application/json' \
--data-raw {{SIGN-RESULT}}

Tras realizarla, debería aparecer la solicitud de aprobación a los nodos WFO y SFO. Puedes comprobarlo de la siguiente manera: After making this request, you should see the approval request to WFO and SFO. You can check it as follows:

curl --request GET 'http://localhost:3002/approval-requests?status=pending'

curl --request GET 'http://localhost:3003/approval-requests?status=pending'

We will try to approve it on one of the two nodes, for example, on SFO:

curl --request PATCH 'http://localhost:3003/approval-requests/{{PREVIUS-ID}}' \
--header 'Content-Type: application/json' \
--data-raw '{"state": "RespondedAccepted"}'

If everything went well, when you launch the subject query request, it should appear with sn 2 and the organic_certified set to false:

curl --request GET 'http://localhost:3001/subjects?subject_type=all&governanceid={{GOVERNANCE-ID}}'

{
    "subject_id": "{{SUBJECT-ID}}",
    "governance_id": "{{GOVERNANCE-ID}}",
    "sn": 2,
    "public_key": "E5DkRaljajwUZ1HrpgdkIxdTu0fbrg-nqoBJFHqm6GJY",
    "namespace": "Spain",
    "name": "Wine",
    "schema_id": "Wine",
    "owner": "{{CONTROLLER-ID}}",
    "creator": "{{CONTROLLER-ID}}",
    "properties": {
        "grape": "PinotNoir",
        "harvest": 3,
        "organic_certified": false,
        "origin": "spain",
        "temperature_control": {
            "last_check": 0,
            "temperature_ok": true
        }
    },
    "active": true
}

It is demonstrated how with the chosen quorom the event has been approved and the contract has been executed, making the change of the state in governance.