MetaManager

    Metamanager receives different types of messages based on the operations listed below :

    • Insert
    • Delete
    • Query
    • Response
    • NodeConnection

    Insert Operation

    operation messages are received via the cloud when new objects are created.An example could be a new user application pod created/deployed through the cloud.

    Insert Operation

    The insert operation request is received via the cloud by edgehub. It dispatches therequest to the metamanager which saves this message in the local database.metamanager then sends an asynchronous message to edged. edged processes the insert request e,g.by starting the pod and populates the response in the message.metamanager inspects the message, extracts the response and sends it back to edgedwhich sends it back to the cloud.

    The update message flow is similar to an insert operation. Additionally, metamanager checks if the resource being updated has changed locally.If there is a delta, only then the update is stored locally and the message ispassed to edged and response is sent back to the cloud.

    ../../_images/meta-update.pngUpdate Operation

    Delete Operation

    Delete operations are triggered when objects like pods are deleted from thecloud.

    Delete Operation

    ../../_images/meta-query.pngQuery Operation

    Response Operation

    Responses are returned for any operations performed at the cloud/edge. Previous operationsshowed the response flow either from the cloud or locally at the edge.

    NodeConnection operation messages are received from edgeHub to give information about the cloud connection status. metamanager tracks this state in-memory and uses it in certain operationslike remote query to the cloud.

    MetaSync Operation

    operation messages are periodically sent by metamanager to sync the status of thepods running on the edge node. The sync interval is configurable in conf/edge.yaml( defaults to 60 seconds ).