Suspending Members

It is possible to temporarily suspend a member Corda identity that has been granted admission to a membership group. Synonym for a virtual node or group member. of a group. Once a member has been suspended, Corda blocks flow Communication between participants in an application network is peer-to-peer using flows. communication between it and other members of the group. A suspended member performing a member lookup can only see updates from the MGM Membership Group Manager. May also be referred to as the Network Manager. It is a virtual node and Corda identity that acts as a central registrar for group membership. and not from other members. It is not possible to suspend the MGM. This section describes how to perform the following:

• Search for Members
• Suspend a Member
• Activate a Member

The commands shown in this section, use the following variables:

• MGM_HOLDING_ID — the short hash of the MGM’s holding identity A group’s addressable identity on a network, plus its X.500 name. .
• X500_NAME — the X.500 A series of international standards defining a global directory service protocol for computer networks. It provides a structured framework for storing, accessing, and managing information about network resources and users in a hierarchical and distributed manner. name of the member being suspended or re-activated.
• REST_API_URL — the URL of the REST worker A worker that exposes the intranet HTTPS REST control ports of the Corda cluster. The REST workers support all of the dynamic administration APIs of the cluster, such as APIs to configure the cluster, set up user role based permissions, or create and register virtual nodes. . This may vary depending on where you have deployed your cluster A complete set of worker processes. Clusters require a fully functioning virtual node infrastructure. and how you have forwarded the ports. For example, https://localhost:8888/api/v5_1.
• REST_API_USER — your username for invoking the REST API.
• REST_API_PASSWORD — your password for invoking the REST API.
• AUTH_INFO — the authentication information if using PowerShell. You can set this as follows:

  $AUTH_INFO = [Convert]::ToBase64String([Text.Encoding]::ASCII.GetBytes(("${REST_API_USER}:${REST_API_PASSWORD}" -f $username,$password)))
  

Search for Members

You can use the Member Lookup REST endpoint to query for all members with a particular status by specifying the MGM and the status. By default, the endpoint only returns members with the status ACTIVE. You can also query for multiple statuses together. For example, to query for all members with the status SUSPENDED:

curl -k -u $REST_API_USER:$REST_API_PASSWORD "$REST_API_URL/members/$MGM_HOLDING_ID?statuses=SUSPENDED"

Invoke-RestMethod -SkipCertificateCheck -Headers @{Authorization=("Basic {0}" -f $AUTH_INFO)}`
   -Method Get -Uri $REST_API_URL/members/$MGM_HOLDING_ID`?statuses=SUSPENDED

The GET method of the /api/v5_1/members/{holdingidentityshorthash} endpoint returns a list of members, specifying the memberContext and mgmContext of each. You can extract the serial number of a member from the corda.serial field inside the mgmContext. This serial number should be used when suspending or activating a member.

Suspend a Member

You can use the POST method of the /api/v5_1/members/{holdingidentityshorthash}/suspend endpoint to suspend a member of a group:

curl -k -u $REST_API_USER:$REST_API_PASSWORD -X 'POST' "$REST_API_URL/mgm/$MGM_HOLDING_ID/suspend" -H 'Content-Type: application/json' \
 -d '{"x500Name": '\"$MEMBER_X500_NAME\"', "serialNumber": "<serial-number>"}'

Invoke-RestMethod -SkipCertificateCheck -Headers @{Authorization=("Basic {0}" -f $AUTH_INFO)}`
  -Method Post -Uri $REST_API_URL/mgm/$MGM_HOLDING_ID/suspend -Body (ConvertTo-Json -Depth 1 @{
  x500Name = $MEMBER_X500_NAME; serialNumber = <serial-number>})

<serial-number> is the current serial number of the member, as retrieved by the Member Lookup endpoint. If the serial number does not match, the method returns a 409 CONFLICT. This can happen if another process has updated the member information, before the suspension operation. If this occurs, you can query the Member Lookup endpoint again and decide whether to proceed with the operation.

Activate a Member

You can use the POST method of the /api/v5_1/members/{holdingidentityshorthash}/activate endpoint to re-activate a suspended member of a group:

curl -k -u $REST_API_USER:$REST_API_PASSWORD -X 'POST' "$REST_API_URL/mgm/$MGM_HOLDING_ID/activate" -H 'Content-Type: application/json' \
 -d '{"x500Name": '\"$MEMBER_X500_NAME\"', "serialNumber": "<serial-number>"}'

Invoke-RestMethod -SkipCertificateCheck  -Headers @{Authorization=("Basic {0}" -f $AUTH_INFO)}`
  -Method Post -Uri $REST_API_URL/mgm/$MGM_HOLDING_ID/activate -Body (ConvertTo-Json -Depth 1 @{
  x500Name = $MEMBER_X500_NAME; serialNumber = <serial-number>})

<serial-number> is the current serial number of the member, as retrieved by the Member REST endpoint. If the serial number does not match, the method returns a 409 CONFLICT.

Once a member has been re-activated, flow communication between it and other members can resume.