fetch

The fetch method fetches a server object by ticket and returns an ExportTicket. This is a low-level method that can be used to fetch any server object (not just tables).

The ticket represents a fetchable server object, such as a PluginClient or Fetchable. This method is used together with the publish method to share server objects between sessions.

Note

For tables specifically, use the higher-level fetch_table method instead.

Syntax

fetch(ticket: Ticket) -> ExportTicket

Parameters

Parameter	Type	Description
ticket	Ticket	The ticket representing a fetchable server object.

Returns

An ExportTicket object that can be used to reference the fetched server object.

Examples

Fetching and publishing a Figure object

The following example fetches a Figure (plot) object and publishes it to a shared ticket.

from pydeephaven import Session
from pydeephaven.ticket import SharedTicket, ServerObject

# Create a session and generate a plot
session = Session(host="localhost", port=10000)
session.run_script("""
from deephaven.plot.figure import Figure
from deephaven import empty_table

source = empty_table(20).update([
    "X = 0.1 * i",
    "Y = randomDouble(0.0, 5.0)"
])

plot = Figure().plot_xy(
    series_name="Random numbers",
    t=source,
    x="X",
    y="Y"
).show()
""")

# Get the plot object from the session
plot_obj = session.exportable_objects["plot"]

# Create a plugin client to interact with the plot
plugin_client = session.plugin_client(plot_obj)

# Fetch the plugin object to get an export ticket
export_ticket = session.fetch(plugin_client)

# Now you can publish this export ticket to share it with other sessions
shared_ticket = SharedTicket.random_ticket()
session.publish(export_ticket, shared_ticket)

plugin_client.close()
session.close()

Fetching a table using generic fetch

While fetch_table is recommended for tables, you can also use the generic fetch method:

from pydeephaven import Session
from pydeephaven.ticket import ScopeTicket

# Create a session and table
session = Session(host="localhost", port=10000)
session.run_script("source = empty_table(20).update('X = i')")

# Fetch the table as an export ticket using the generic fetch method
export_ticket = session.fetch(ScopeTicket.scope_ticket("source"))

# The export_ticket can now be used to reference the table
# or published to a shared ticket for other sessions to access

session.close()

Fetching a shared plugin object

The following example shows how to fetch a plugin object that was published to a shared ticket by another session.

from pydeephaven import Session
from pydeephaven.ticket import SharedTicket, ServerObject

# Assume another session published a Figure to this shared ticket
shared_ticket = SharedTicket.random_ticket()  # Use the actual shared ticket

# Connect to the session and fetch the shared object
session = Session(host="localhost", port=10000)

# Create a ServerObject reference with the appropriate type
server_obj = ServerObject(type="Figure", ticket=shared_ticket)

# Create a plugin client to interact with the shared Figure
plugin_client = session.plugin_client(server_obj)

# You can now interact with the Figure through the plugin client
payload, refs = next(plugin_client.resp_stream)

plugin_client.close()
session.close()