Update contacts and contact versioning

AWS Ground Station supports updating contacts with a SCHEDULED, PREPASS, or PASS contact status. You can use the UpdateContact API to specify an ephemeris override for a contact — including azimuth/elevation, OEM, or TLE tracking data — without cancelling and rescheduling it. This is useful for geosynchronous (GEO) satellite operations where you need to retask an antenna to a different satellite during a contact, or for Launch and Early Operations (LEOPs) where pointing adjustments are required.

Each time you reserve or update a contact, AWS Ground Station creates a new contact version. Contact versions provide a history of changes made to a contact and allow you to track the status of each update.

How contact versioning works

When you call ReserveContact, AWS Ground Station creates the first version of the contact (version 1) and returns the versionId in the response. Each subsequent call to UpdateContact creates a new version with an incremented version number.

The DescribeContact API returns the currently ACTIVE contact version, including version information in the version field of the response. The ListContacts API also includes version information for each contact.

To view a specific version of a contact, use the DescribeContactVersion API. To list all versions of a contact, use the ListContactVersions API.

Updating a contact

You can call UpdateContact when a contact is in the SCHEDULED, PREPASS, or PASS state. The API accepts the following parameters:

You can change the target satellite during a contact by providing a new satelliteArn along with the corresponding trackingOverrides. The new satellite must be visible from the ground station for the duration of the contact, because the contact start and end time do not change with this API. The new satellite must also be onboarded to the ground station and have the licensing required by the mission profile. The mission profile of the contact cannot be changed, so switching satellites is only applicable when both satellites use the same mission profile.

The UpdateContact API returns the contactId and the new versionId. The update is processed asynchronously. Use DescribeContactVersion to check the status of the update. Some AWS SDKs and the AWS Command Line Interface provide a ContactUpdated waiter that polls until the version reaches ACTIVE or FAILED_TO_UPDATE status.

Contact version statuses

Each contact version has one of the following statuses:

Code examples

The following examples demonstrate how to use the contact versioning APIs with the AWS SDK for Python (Boto3).

Example: Update a contact

The following example updates a contact with new tracking overrides and waits for the update to complete using the Boto3 ContactUpdated waiter.

import boto3
import uuid

# Create AWS Ground Station client
ground_station_client = boto3.client("groundstation")

# The contact ID of an existing scheduled contact to update
contact_id = "a1b2c3d4-5678-90ab-cdef-EXAMPLE11111"

# Generate a unique client token for idempotency.
# If you retry the same request with the same client token,
# the API returns the same response without creating a duplicate version.
client_token = str(uuid.uuid4())

# Update the contact to use a different TLE ephemeris for tracking.
# The UpdateContact API applies all parameters in the request.
# Any parameter set to null is treated as a request to clear that value,
# not to leave it unchanged. Include all desired values in each request.
print(f"Updating contact {contact_id}...")

update_response = ground_station_client.update_contact(
    contactId=contact_id,
    clientToken=client_token,
    satelliteArn="arn:aws:groundstation::111122223333:satellite/a88611b0-f755-404e-b60d-57d8aEXAMPLE",
    trackingOverrides={
        "programTrackSettings": {
            "tle": {"ephemerisId": "b2c3d4e5-6789-01ab-cdef-EXAMPLE22222"}
        }
    },
)

contact_id = update_response["contactId"]
version_id = update_response["versionId"]
print(f"Update submitted. Contact: {contact_id}, Version: {version_id}")

# Wait for the update to complete using the ContactUpdated waiter.
# The waiter polls DescribeContactVersion until the version reaches
# ACTIVE (success) or FAILED_TO_UPDATE (failure) status.
# The waiter raises WaiterError if the version reaches FAILED_TO_UPDATE
# or if MaxAttempts is exceeded, so we use try/except to handle both cases.
print("Waiting for update to complete...")

from botocore.exceptions import WaiterError

waiter = ground_station_client.get_waiter("contact_updated")

try:
    waiter.wait(
        contactId=contact_id,
        versionId=version_id,
        WaiterConfig={
            "Delay": 5,
            "MaxAttempts": 180,
        },
    )
    print(f"Contact updated successfully. Version {version_id} is now active.")
except WaiterError as e:
    # WaiterError is raised when the version reaches FAILED_TO_UPDATE
    # or when MaxAttempts is exceeded. Retrieve the current version to inspect.
    version_response = ground_station_client.describe_contact_version(
        contactId=contact_id,
        versionId=version_id,
    )
    version_status = version_response["version"]["status"]
    if version_status == "FAILED_TO_UPDATE":
        failure_codes = version_response["version"].get("failureCodes", [])
        failure_message = version_response["version"].get("failureMessage", "")
        print(f"Update failed. Codes: {failure_codes}, Message: {failure_message}")
    else:
        print(f"Waiter timed out. Current version status: {version_status}. Error: {e}")

Example: Describe a contact version

The following example retrieves the details of a specific contact version, including its status, configuration, and any failure information.

import boto3

# Create AWS Ground Station client
ground_station_client = boto3.client("groundstation")

contact_id = "a1b2c3d4-5678-90ab-cdef-EXAMPLE11111"
version_id = 2

# Describe a specific version of a contact.
# Use this API to check the status of an update or to view the
# configuration that was active at a specific point in time.
print(f"Describing version {version_id} of contact {contact_id}...")

response = ground_station_client.describe_contact_version(
    contactId=contact_id,
    versionId=version_id,
)

# Display version details
version = response["version"]
print(f"Version ID: {version['versionId']}")
print(f"Status: {version['status']}")
print(f"Created: {version.get('created', 'N/A')}")

if version.get("activated"):
    print(f"Activated: {version['activated']}")

if version.get("superseded"):
    print(f"Superseded: {version['superseded']}")

# Display contact details for this version
print(f"\nContact ID: {response['contactId']}")
print(f"Contact Status: {response['contactStatus']}")
print(f"Ground Station: {response['groundStation']}")
print(f"Start Time: {response['startTime']}")
print(f"End Time: {response['endTime']}")

if response.get("satelliteArn"):
    print(f"Satellite ARN: {response['satelliteArn']}")

if response.get("trackingOverrides"):
    print(f"Tracking Overrides: {response['trackingOverrides']}")

# Check for failure details if the version failed to update
if version["status"] == "FAILED_TO_UPDATE":
    failure_codes = version.get("failureCodes", [])
    failure_message = version.get("failureMessage", "")
    print(f"\nFailure Codes: {failure_codes}")
    print(f"Failure Message: {failure_message}")

Example: List contact versions

The following example lists all versions of a contact to view the full history of changes, using pagination to handle large result sets.

import boto3

# Create AWS Ground Station client
ground_station_client = boto3.client("groundstation")

contact_id = "a1b2c3d4-5678-90ab-cdef-EXAMPLE11111"

# List all versions of a contact to view the full history of changes.
# Results are paginated. Use the nextToken to retrieve additional pages.
print(f"Listing versions for contact {contact_id}...")

paginator = ground_station_client.get_paginator("list_contact_versions")
page_iterator = paginator.paginate(
    contactId=contact_id,
    PaginationConfig={
        "MaxItems": 100,
        "PageSize": 20,
    },
)

for page in page_iterator:
    for version in page["contactVersionsList"]:
        version_id = version["versionId"]
        status = version["status"]
        created = version.get("created", "N/A")

        print(f"  Version {version_id}: status={status}, created={created}")

        if version.get("activated"):
            print(f"    Activated: {version['activated']}")

        if version.get("superseded"):
            print(f"    Superseded: {version['superseded']}")

        if status == "FAILED_TO_UPDATE":
            failure_codes = version.get("failureCodes", [])
            failure_message = version.get("failureMessage", "")
            print(f"    Failure Codes: {failure_codes}")
            print(f"    Failure Message: {failure_message}")

        if status == "UPDATING":
            print(f"    Update is currently in progress.")

Considerations