Launching and connecting to a Modeler instance#

PyAnsys Geometry provides the ability to launch and connect to a Modeler instance either locally or remotely. A Modeler instance is a running instance of a CAD service that the PyAnsys Geometry client can communicate with.

CAD services that are supported include:

Ansys Geometry Service
Ansys Discovery
Ansys SpaceClaim

Connecting to a Modeler instance#

To connect to a Modeler instance, you can use the Modeler() class, which provides methods to connect to the desired CAD service. You can specify the connection parameters such as the host, port, and authentication details.

from ansys.geometry.core import Modeler

# Connect to a local Modeler instance
modeler = Modeler(host="localhost", port=12345)

Connection types#

PyAnsys Geometry supports different connection types to connect to a Modeler instance, which differ in the environment in which the transport takes place:

Local connection: The Modeler instance is running on the same machine as the PyAnsys Geometry client. This is typically used for development and testing purposes.
Remote connection: The service instance is running on a different machine, and the Modeler client connects to it over the network. This is useful for accessing Modeler instances hosted on remote servers or cloud environments.

Securing connections#

When connecting to a remote Modeler instance, it is important to ensure that the connection is secure, not only to protect sensitive data but also to comply with organizational security policies. These secure connections can be established using various methods, such as:

mTLS: Mutual Transport Layer Security (mTLS) is a security protocol that ensures both the client and server authenticate each other using digital certificates. This provides a high level of security for the connection. PyAnsys Geometry supports mTLS connections to Modeler instances. In that case, you need to provide the necessary certificates and keys when establishing the connection. More information on the certificates needed can be seen in Generating certificates for mTLS. Make sure that the names of the files are in line with the previous link. An example of how to set up an mTLS connection is shown below:

Note

mTLS is the default transport mode when connecting to remote Modeler instances.
```
from ansys.geometry.core import Modeler, launch_modeler

# OPTION 1: Connect to a Modeler instance using mTLS
modeler = Modeler(
    host="remote_host",
    port=12345,
    transport_mode="mtls",
    certs_dir="path/to/certs_directory",
)

# OPTION 2: Launch the Modeler instance locally using mTLS
modeler = launch_modeler(
    transport_mode="mtls",
    certs_dir="path/to/certs_directory",
)
```

UDS: Unix Domain Sockets (UDS) provide a way to establish secure connections between processes on the same machine. UDS connections are faster and more secure than traditional network connections, as they do not require network protocols. PyAnsys Geometry supports UDS connections to local Modeler instances (only on Linux-based services). An example of how to set up a UDS connection is shown below:

Note

UDS is only supported when connecting to local Modeler instances on Linux-based services. It is also the default transport mode in such cases.

from ansys.geometry.core import Modeler, launch_modeler

# OPTION 1: Connect to a local Modeler instance using UDS
modeler = Modeler(host="localhost", port=12345, transport_mode="uds")

# OPTION 2: Launch the Modeler instance locally using UDS and specific directory and id for
# the UDS socket
modeler = Modeler(host="localhost", port=12345, transport_mode="uds", uds_dir="/path/to/uds_directory", uds_id="unique_id")

# OPTION 3: Launch the Modeler instance locally using UDS
modeler = launch_modeler(transport_mode="uds")

# OPTION 4: Launch the Modeler instance locally using UDS and specific directory and id for
# the UDS socket
modeler = launch_modeler(transport_mode="uds", uds_dir="/path/to/uds_directory", uds_id="unique_id")

WNUA: Windows Named User Authentication (WNUA) provides a way to establish secure connections between processes on the same Windows machine. WNUA connections use a built-in mechanism to verify that the owner of the service running is also the owner of the client connection established (similar to UDS). PyAnsys Geometry supports WNUA connections to local Modeler instances (only on Windows-based services). An example of how to set up a WNUA connection is shown below:

Note

WNUA is only supported when connecting to local Modeler instances on Windows-based services. It is also the default transport mode in such cases.
```
from ansys.geometry.core import Modeler, launch_modeler

# OPTION 1: Connect to a local Modeler instance using WNUA
modeler = Modeler(host="localhost", port=12345, transport_mode="wnua")

# OPTION 2: Launch the Modeler instance locally using WNUA
modeler = launch_modeler(transport_mode="wnua")
```

Insecure: Insecure connections do not provide any security measures to protect the data transmitted between the client and server. This mode is not recommended for production use, as it exposes the connection to potential security risks. However, it can be useful for development and testing purposes in trusted environments. An example of how to set up an insecure connection is shown below:

from ansys.geometry.core import Modeler, launch_modeler

# OPTION 1: Connect to a Modeler instance using an insecure connection
modeler = Modeler(
    host="remote_host",
    port=12345,
    transport_mode="insecure",
)

# OPTION 2: Launch the Modeler instance locally using an insecure connection
modeler = launch_modeler(
    transport_mode="insecure",
)

For more information on secure connections and transport modes, see Securing gRPC connections.