create-cursor

Description

Creates a cursor. Cursors are used to consume a stream, starting from a specific point in the partition and going forward from there. You can create a cursor based on an offset, a time, the trim horizon, or the most recent message in the stream. As the oldest message inside the retention period boundary, using the trim horizon effectively lets you consume all messages in the stream. A cursor based on the most recent message allows consumption of only messages that are added to the stream after you create the cursor. Cursors expire five minutes after you receive them from the service.

The top level –endpoint parameter must be supplied for this operation.

Usage

oci streaming stream cursor create-cursor [OPTIONS]

Required Parameters

--partition [text]

The partition to get messages from.

--stream-id [text]

The OCID of the stream.

--type [text]

The type of cursor, which determines the starting point from which the stream will be consumed:

  • AFTER_OFFSET: The partition position immediately following the offset you specify. (Offsets are assigned when you successfully append a message to a partition in a stream.) - AT_OFFSET: The exact partition position indicated by the offset you specify. - AT_TIME: A specific point in time. - LATEST: The most recent message in the partition that was added after the cursor was created. - TRIM_HORIZON: The oldest message in the partition that is within the retention period window.

Accepted values are:

AFTER_OFFSET, AT_OFFSET, AT_TIME, LATEST, TRIM_HORIZON

Optional Parameters

--from-json [text]

Provide input to this command as a JSON document from a file using the file://path-to/file syntax.

The --generate-full-command-json-input option can be used to generate a sample json file to be used with this command option. The key names are pre-populated and match the command option names (converted to camelCase format, e.g. compartment-id –> compartmentId), while the values of the keys need to be populated by the user before using the sample file as an input to this command. For any command option that accepts multiple values, the value of the key can be a JSON array.

Options can still be provided on the command line. If an option exists in both the JSON document and the command line then the command line specified value will be used.

For examples on usage of this option, please see our “using CLI with advanced JSON options” link: https://docs.cloud.oracle.com/iaas/Content/API/SDKDocs/cliusing.htm#AdvancedJSONOptions

--offset [integer]

The offset to consume from if the cursor type is AT_OFFSET or AFTER_OFFSET.

--time [datetime]

The time to consume from if the cursor type is AT_TIME, expressed in RFC 3339 timestamp format.

The following datetime formats are supported:

UTC with microseconds

Format: YYYY-MM-DDTHH:mm:ss.ssssssTZD
Example: 2017-09-15T20:30:00.123456Z

UTC with milliseconds
***********************
.. code::

    Format: YYYY-MM-DDTHH:mm:ss.sssTZD
    Example: 2017-09-15T20:30:00.123Z

UTC without milliseconds
**************************
.. code::

    Format: YYYY-MM-DDTHH:mm:ssTZD
    Example: 2017-09-15T20:30:00Z

UTC with minute precision
**************************
.. code::

    Format: YYYY-MM-DDTHH:mmTZD
    Example: 2017-09-15T20:30Z

Timezone with microseconds

Format: YYYY-MM-DDTHH:mm:ssTZD
Example: 2017-09-15T12:30:00.456789-08:00, 2017-09-15T12:30:00.456789-0800

Timezone with milliseconds
***************************
.. code::

    Format: YYYY-MM-DDTHH:mm:ssTZD
    Example: 2017-09-15T12:30:00.456-08:00, 2017-09-15T12:30:00.456-0800

Timezone without milliseconds
*******************************
.. code::

    Format: YYYY-MM-DDTHH:mm:ssTZD
    Example: 2017-09-15T12:30:00-08:00, 2017-09-15T12:30:00-0800

Timezone with minute precision
*******************************
.. code::

    Format: YYYY-MM-DDTHH:mmTZD
    Example: 2017-09-15T12:30-08:00, 2017-09-15T12:30-0800

Short date and time
********************
The timezone for this date and time will be taken as UTC (Needs to be surrounded by single or double quotes)

.. code::

    Format: 'YYYY-MM-DD HH:mm' or "YYYY-MM-DD HH:mm"
    Example: '2017-09-15 17:25'

Date Only
**********
This date will be taken as midnight UTC of that day

.. code::

    Format: YYYY-MM-DD
    Example: 2017-09-15

Epoch seconds
**************
.. code::

    Example: 1412195400

Example using required parameter

Copy the following CLI commands into a file named example.sh. Run the command by typing “bash example.sh” and replacing the example parameters with your own.

Please note this sample will only work in the POSIX-compliant bash-like shell. You need to set up the OCI configuration and appropriate security policies before trying the examples.

    export name=<substitute-value-of-name> # https://docs.cloud.oracle.com/en-us/iaas/tools/oci-cli/latest/oci_cli_docs/cmdref/streaming/admin/stream/create.html#cmdoption-name
    export partitions=<substitute-value-of-partitions> # https://docs.cloud.oracle.com/en-us/iaas/tools/oci-cli/latest/oci_cli_docs/cmdref/streaming/admin/stream/create.html#cmdoption-partitions
    export type=<substitute-value-of-type> # https://docs.cloud.oracle.com/en-us/iaas/tools/oci-cli/latest/oci_cli_docs/cmdref/streaming/stream/cursor/create-cursor.html#cmdoption-type

    stream_id=$(oci streaming admin stream create --name $name --partitions $partitions --query data.id --raw-output)

    oci streaming stream cursor create-cursor --partition $partition --stream-id $stream_id --type $type