How to programmatically retrieve vCenter Server Patch & Update History?

Homelab just upgraded successfully to vSphere 7.0 Update 3!

I really appreciate the “History” view to be able to see all the updates/patches that have been applied for your vCenter Server. Its the little things pic.twitter.com/Go9eicpeSp

— William Lam (@lamw) October 7, 2021

After upgrading my homelab to the latest vSphere 7.0 Update 3 release, I was just looking at the "History" tab within the Virtual Machine Management Interface (VAMI), which gives you a historical view of all the patches and updates that have been applied to your vCenter Server since its initial deployment. I am not exactly sure when this was feature was introduced, but it can definitely be useful for both auditing but also debugging/troubleshooting purposes.

Of course, I was curious about this information and wanted to see if I could retrieve it using something like PowerCLI. However when I started to look for the API, I realized that there may not be a public API for this ... but that did not stopped me and taking a look at Chrome Developer, I quickly saw the endpoint which was /rest/appliance/update/history and I was able to figure out a workaround giving the same data.

Below are two examples on accessing this data using either PowerShell or cURL

PowerShell

$VAMI_USERNAME="FILL_ME_IN"
$VAMI_PASSWORD="FILL_ME_IN"
$VCSA_HOSTNAME="vcsa.primp-industries.local"

$pair = "${VAMI_USERNAME}:${VAMI_PASSWORD}"
$bytes = [System.Text.Encoding]::ASCII.GetBytes($pair)
$base64 = [System.Convert]::ToBase64String($bytes)
$basicAuthValue = "Basic $base64"

$headers = @{
    "authorization"="$basicAuthValue"
    "Content-Type"="application/json"
    "Accept"="application/json"
}

$uri = "https://${VCSA_HOSTNAME}:5480/rest/appliance/update/history"

$results = Invoke-WebRequest -Uri $uri -Method GET -Headers $headers -UseBasicParsing -SkipCertificateCheck
$jsonResults = ($results.Content | ConvertFrom-Json).Value

cURL

VAMI_USERNAME=FILL_ME_IN
VAMI_PASSWORD=FILL_ME_IN
VCSA_HOSTNAME="vcsa.primp-industries.local"

curl -s -k -u ${VAMI_USERNAME}:${VAMI_PASSWORD} https://${VCSA_HOSTNAME}:5480/rest/appliance/update/history | jq