pynetdicom.events.Event¶

class pynetdicom.events.Event(assoc: Association, event: NotificationEvent | InterventionEvent, attrs: dict[str, Any] | None = None)[source]¶

Representation of an event.

Added in version 1.3.

Warning

Some of Event’s attributes are set dynamically when an event is triggered and are available only for a specific event. For example, the Event.context attribute is only available for events such as evt.EVT_C_ECHO, evt.EVT_C_STORE, etc. See the handler documentation for a list of what attributes are available for a given event.

assoc¶

The association in which the event occurred.

Type:: association.Association

timestamp¶

The date/time the event was created. Will be slightly before or after the actual event that this object represents.

Type:: datetime.datetime

__init__(assoc: Association, event: NotificationEvent | InterventionEvent, attrs: dict[str, Any] | None = None) → None[source]¶

Create a new Event.

Parameters:

assoc (association.Association) – The association in which the event occurred.
event (events.NotificationEvent or events.InterventionEvent) – The representation of the event that occurred.
attrs (dict, optional) – The {attribute : value} pairs to use to set the Event’s attributes.

Methods

`__init__`(assoc, event[, attrs])	Create a new Event.
`encoded_dataset`([include_meta])	Return the encoded C-STORE dataset sent by the peer without first decoding it.

Attributes

`action_information`	Return an N-ACTION request's Action Information as a pydicom `Dataset`.
`action_type`	Return an N-ACTION request's Action Type ID as an `int`.
`attribute_identifiers`	Return an N-GET request's Attribute Identifier List as a `list` of pydicom `BaseTag`.
`attribute_list`	Return an N-CREATE request's Attribute List as a pydicom `Dataset`.
`dataset`	Return a C-STORE request's Data Set as a pydicom `Dataset`.
`dataset_path`	Return the path to the dataset when `STORE_RECV_CHUNKED_DATASET` is `True`.
`event`	Return the corresponding event.
`event_information`	Return an N-EVENT-REPORT request's Event Information as a pydicom `Dataset`.
`event_type`	Return an N-EVENT-REPORT request's Event Type ID as an `int`.
`file_meta`	Return a pydicom `Dataset` with the File Meta Information for a C-STORE request's Data Set.
`identifier`	Return a C-FIND, C-GET or C-MOVE request's Identifier as a pydicom `Dataset`.
`is_cancelled`	Return `True` if a C-CANCEL request has been received.
`message_id`	Return a DIMSE service request's Message ID as `int`.
`modification_list`	Return an N-SET request's Modification List as a pydicom `Dataset`.
`move_destination`	Return a C-MOVE request's Move Destination as `str`.

property action_information: Dataset¶

Return an N-ACTION request’s Action Information as a pydicom Dataset.

Because pydicom defers data parsing during decoding until an element is actually required the returned Dataset may raise an exception when any element is first accessed. It’s therefore important that proper error handling be part of any handler that uses the returned Dataset.

Returns:: The decoded Action Information dataset.
Return type:: pydicom.dataset.Dataset
Raises:: AttributeError – If the corresponding event is not an N-ACTION request.

property action_type: int | None¶

Return an N-ACTION request’s Action Type ID as an int.

Added in version 1.4.

Returns:: The request’s (0000,1008) Action Type ID value, may be None if the peer’s N-ACTION request is non-conformant.
Return type:: int or None
Raises:: AttributeError – If the corresponding event is not an N-ACTION request.

property attribute_identifiers: list[BaseTag]¶

Return an N-GET request’s Attribute Identifier List as a list of pydicom BaseTag.

Returns:: The (0000,1005) Attribute Identifier List tags, may be an empty list if no Attribute Identifier List was included in the C-GET request.
Return type:: list of pydicom.tag.BaseTag
Raises:: AttributeError – If the corresponding event is not an N-GET request.

property attribute_list: Dataset¶

Return an N-CREATE request’s Attribute List as a pydicom Dataset.

Because pydicom defers data parsing during decoding until an element is actually required the returned Dataset may raise an exception when any element is first accessed. It’s therefore important that proper error handling be part of any handler that uses the returned Dataset.

Returns:: The decoded Attribute List dataset.
Return type:: pydicom.dataset.Dataset
Raises:: AttributeError – If the corresponding event is not an N-CREATE request.

property dataset: Dataset¶

Return a C-STORE request’s Data Set as a pydicom Dataset.

Because pydicom defers data parsing during decoding until an element is actually required the returned Dataset may raise an exception when any element is first accessed. It’s therefore important that proper error handling be part of any handler that uses the returned Dataset.

Returns:: The decoded Data Set dataset.
Return type:: pydicom.dataset.Dataset
Raises:: AttributeError – If the corresponding event is not a C-STORE request.

property dataset_path: Path¶

Return the path to the dataset when STORE_RECV_CHUNKED_DATASET is True.

Added in version 2.0.

Returns:: The path to the dataset.
Return type:: pathlib.Path

encoded_dataset(include_meta: bool = True) → bytes[source]¶

Return the encoded C-STORE dataset sent by the peer without first decoding it.

Added in version 2.1.

Examples

Retrieve the encoded dataset as sent by the peer:

def handle_store(event: pynetdicom.events.Event) -> int:
    stream: bytes = event.encoded_dataset(include_meta=False)

    return 0x0000

Write the encoded dataset to file in the DICOM File Format without having to first decode it:

def handle_store(event: pynetdicom.events.Event, dst: pathlib.Path) -> int:
    with dst.open("wb") as f:
        f.write(event.encoded_dataset())

    return 0x0000

Parameters:: include_meta (bool, optional) – If True (default) then include the encoded DICOM preamble, prefix and file meta information with the returned bytestream.
Returns:: The encoded dataset as sent by the peer, with or without the file meta information.
Return type:: bytes
Raises:: AttributeError – If the corresponding event is not a C-STORE request.

property event: NotificationEvent | InterventionEvent¶

Return the corresponding event.

Added in version 1.4.

Returns:: The corresponding event as a namedtuple.
Return type:: events.InterventionEvent or events.NotificationEvent

property event_information: Dataset¶

Return an N-EVENT-REPORT request’s Event Information as a pydicom Dataset.

Because pydicom defers data parsing during decoding until an element is actually required the returned Dataset may raise an exception when any element is first accessed. It’s therefore important that proper error handling be part of any handler that uses the returned Dataset.

Returns:: The decoded Event Information dataset.
Return type:: pydicom.dataset.Dataset
Raises:: AttributeError – If the corresponding event is not an N-EVENT-REPORT request.

property event_type: int | None¶

Return an N-EVENT-REPORT request’s Event Type ID as an int.

Added in version 1.4.

Returns:: The request’s (0000,1002) Event Type ID value, may be None if the peer’s N-EVENT-REPORT request is non-conformant.
Return type:: int or None
Raises:: AttributeError – If the corresponding event is not an N-EVENT-REPORT request.

property file_meta: FileMetaDataset¶

Return a pydicom Dataset with the File Meta Information for a C-STORE request’s Data Set.

Contains the following File Meta Information elements:

(0002,0000) File Meta Information Group Length - set as 0, will be updated with the correct value during write
(0002,0001) File Meta Information Version - set as 0x0001
(0002,0002) Media Storage SOP Class UID - set from the request’s Affected SOP Class UID
(0002,0003) Media Storage SOP Instance UID - set from the request’s Affected SOP Instance UID
(0002,0010) Transfer Syntax UID - set from the presentation context used to transfer the Data Set
(0002,0012) Implementation Class UID - set using PYNETDICOM_IMPLEMENTATION_UID
(0002,0013) Implementation Version Name - set using PYNETDICOM_IMPLEMENTATION_VERSION

Examples

Add the File Meta Information to the decoded Data Set and save it to the DICOM File Format.

>>> ds = event.dataset
>>> ds.file_meta = event.file_meta
>>> ds.save_as('example.dcm', write_like_original=False)

Encode the File Meta Information in a new file and append the encoded Data Set to it. This skips having to decode/re-encode the Data Set as in the previous example (or alternatively, just use the encoded_dataset() method).

>>> from pydicom.filewriter import write_file_meta_info
>>> with open('example.dcm', 'wb') as f:
...     f.write(b'\x00' * 128)
...     f.write(b'DICM')
...     write_file_meta_info(f, event.file_meta)
...     f.write(event.request.DataSet.getvalue())

Returns:: The File Meta Information suitable for use with the decoded C-STORE request’s Data Set.
Return type:: pydicom.dataset.Dataset
Raises:: AttributeError – If the corresponding event is not a C-STORE request.

property identifier: Dataset¶

Return a C-FIND, C-GET or C-MOVE request’s Identifier as a pydicom Dataset.

Because pydicom defers data parsing during decoding until an element is actually required the returned Dataset may raise an exception when any element is first accessed. It’s therefore important that proper error handling be part of any handler that uses the returned Dataset.

Returns:: The decoded Identifier dataset.
Return type:: pydicom.dataset.Dataset
Raises:: AttributeError – If the corresponding event is not a C-FIND, C-GET or C-MOVE request.

property is_cancelled: bool¶

Return True if a C-CANCEL request has been received.

Returns:: If this event corresponds to a C-FIND, C-GET or C-MOVE request being received by a Service Class then returns True if a C-CANCEL request with a Message ID Being Responded To parameter value corresponding to the Message ID of the service request has been received. If no such C-CANCEL request has been received or if the event is not a C-FIND, C-GET or C-MOVE request then returns False.
Return type:: bool

property message_id: int¶

Return a DIMSE service request’s Message ID as int.

Added in version 1.5.

Returns:: The request’s (0000,0110) Message ID value.
Return type:: int
Raises:: AttributeError – If the corresponding event is not one of the DIMSE service requests.

property modification_list: Dataset¶

Return an N-SET request’s Modification List as a pydicom Dataset.

Because pydicom defers data parsing during decoding until an element is actually required the returned Dataset may raise an exception when any element is first accessed. It’s therefore important that proper error handling be part of any handler that uses the returned Dataset.

Returns:: The decoded Modification List dataset.
Return type:: pydicom.dataset.Dataset
Raises:: AttributeError – If the corresponding event is not an N-SET request.

property move_destination: str | None¶

Return a C-MOVE request’s Move Destination as str.

Added in version 1.4.

Changed in version 2.0: Changed to return str and trailing spaces removed.

Returns:: The request’s (0000,0600) Move Destination value, without any trailing padding spaces. May be None if the peer’s C-MOVE request is non-conformant.
Return type:: str or None
Raises:: AttributeError – If the corresponding event is not a C-MOVE request.