Metadata-Version: 2.1
Name: dlt
Version: 0.0.0
Summary: Python implementation for DLT
Author-email: BMW CarIT <carit.info@bmw.de>
License: Mozilla Public License Version 2.0
        
           1. Definitions
        
        1.1. "Contributor" means each individual or legal entity that creates, contributes
        to the creation of, or owns Covered Software.
        
        1.2. "Contributor Version" means the combination of the Contributions of others
        (if any) used by a Contributor and that particular Contributor's Contribution.
        
              1.3. "Contribution" means Covered Software of a particular Contributor.
        
        1.4. "Covered Software" means Source Code Form to which the initial Contributor
        has attached the notice in Exhibit A, the Executable Form of such Source Code
        Form, and Modifications of such Source Code Form, in each case including portions
        thereof.
        
              1.5. "Incompatible With Secondary Licenses" means
        
        (a) that the initial Contributor has attached the notice described in Exhibit
        B to the Covered Software; or
        
        (b) that the Covered Software was made available under the terms of version
        1.1 or earlier of the License, but not also under the terms of a Secondary
        License.
        
        1.6. "Executable Form" means any form of the work other than Source Code Form.
        
        1.7. "Larger Work" means a work that combines Covered Software with other
        material, in a separate file or files, that is not Covered Software.
        
              1.8. "License" means this document.
        
        1.9. "Licensable" means having the right to grant, to the maximum extent possible,
        whether at the time of the initial grant or subsequently, any and all of the
        rights conveyed by this License.
        
              1.10. "Modifications" means any of the following:
        
        (a) any file in Source Code Form that results from an addition to, deletion
        from, or modification of the contents of Covered Software; or
        
        (b) any new file in Source Code Form that contains any Covered Software.
        
        1.11. "Patent Claims" of a Contributor means any patent claim(s), including
        without limitation, method, process, and apparatus claims, in any patent Licensable
        by such Contributor that would be infringed, but for the grant of the License,
        by the making, using, selling, offering for sale, having made, import, or
        transfer of either its Contributions or its Contributor Version.
        
        1.12. "Secondary License" means either the GNU General Public License, Version
        2.0, the GNU Lesser General Public License, Version 2.1, the GNU Affero General
        Public License, Version 3.0, or any later versions of those licenses.
        
        1.13. "Source Code Form" means the form of the work preferred for making modifications.
        
        1.14. "You" (or "Your") means an individual or a legal entity exercising rights
        under this License. For legal entities, "You" includes any entity that controls,
        is controlled by, or is under common control with You. For purposes of this
        definition, "control" means (a) the power, direct or indirect, to cause the
        direction or management of such entity, whether by contract or otherwise,
        or (b) ownership of more than fifty percent (50%) of the outstanding shares
        or beneficial ownership of such entity.
        
           2. License Grants and Conditions
        
              2.1. Grants
        
        Each Contributor hereby grants You a world-wide, royalty-free, non-exclusive
        license:
        
        (a) under intellectual property rights (other than patent or trademark) Licensable
        by such Contributor to use, reproduce, make available, modify, display, perform,
        distribute, and otherwise exploit its Contributions, either on an unmodified
        basis, with Modifications, or as part of a Larger Work; and
        
        (b) under Patent Claims of such Contributor to make, use, sell, offer for
        sale, have made, import, and otherwise transfer either its Contributions or
        its Contributor Version.
        
              2.2. Effective Date
        
        The licenses granted in Section 2.1 with respect to any Contribution become
        effective for each Contribution on the date the Contributor first distributes
        such Contribution.
        
              2.3. Limitations on Grant Scope
        
        The licenses granted in this Section 2 are the only rights granted under this
        License. No additional rights or licenses will be implied from the distribution
        or licensing of Covered Software under this License. Notwithstanding Section
        2.1(b) above, no patent license is granted by a Contributor:
        
        (a) for any code that a Contributor has removed from Covered Software; or
        
        (b) for infringements caused by: (i) Your and any other third party's modifications
        of Covered Software, or (ii) the combination of its Contributions with other
        software (except as part of its Contributor Version); or
        
        (c) under Patent Claims infringed by Covered Software in the absence of its
        Contributions.
        
        This License does not grant any rights in the trademarks, service marks, or
        logos of any Contributor (except as may be necessary to comply with the notice
        requirements in Section 3.4).
        
              2.4. Subsequent Licenses
        
        No Contributor makes additional grants as a result of Your choice to distribute
        the Covered Software under a subsequent version of this License (see Section
        10.2) or under the terms of a Secondary License (if permitted under the terms
        of Section 3.3).
        
              2.5. Representation
        
        Each Contributor represents that the Contributor believes its Contributions
        are its original creation(s) or it has sufficient rights to grant the rights
        to its Contributions conveyed by this License.
        
              2.6. Fair Use
        
        This License is not intended to limit any rights You have under applicable
        copyright doctrines of fair use, fair dealing, or other equivalents.
        
              2.7. Conditions
        
        Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted in
        Section 2.1.
        
           3. Responsibilities
        
              3.1. Distribution of Source Form
        
        All distribution of Covered Software in Source Code Form, including any Modifications
        that You create or to which You contribute, must be under the terms of this
        License. You must inform recipients that the Source Code Form of the Covered
        Software is governed by the terms of this License, and how they can obtain
        a copy of this License. You may not attempt to alter or restrict the recipients'
        rights in the Source Code Form.
        
              3.2. Distribution of Executable Form
        
              If You distribute Covered Software in Executable Form then:
        
        (a) such Covered Software must also be made available in Source Code Form,
        as described in Section 3.1, and You must inform recipients of the Executable
        Form how they can obtain a copy of such Source Code Form by reasonable means
        in a timely manner, at a charge no more than the cost of distribution to the
        recipient; and
        
        (b) You may distribute such Executable Form under the terms of this License,
        or sublicense it under different terms, provided that the license for the
        Executable Form does not attempt to limit or alter the recipients' rights
        in the Source Code Form under this License.
        
              3.3. Distribution of a Larger Work
        
        You may create and distribute a Larger Work under terms of Your choice, provided
        that You also comply with the requirements of this License for the Covered
        Software. If the Larger Work is a combination of Covered Software with a work
        governed by one or more Secondary Licenses, and the Covered Software is not
        Incompatible With Secondary Licenses, this License permits You to additionally
        distribute such Covered Software under the terms of such Secondary License(s),
        so that the recipient of the Larger Work may, at their option, further distribute
        the Covered Software under the terms of either this License or such Secondary
        License(s).
        
              3.4. Notices
        
        You may not remove or alter the substance of any license notices (including
        copyright notices, patent notices, disclaimers of warranty, or limitations
        of liability) contained within the Source Code Form of the Covered Software,
        except that You may alter any license notices to the extent required to remedy
        known factual inaccuracies.
        
              3.5. Application of Additional Terms
        
        You may choose to offer, and to charge a fee for, warranty, support, indemnity
        or liability obligations to one or more recipients of Covered Software. However,
        You may do so only on Your own behalf, and not on behalf of any Contributor.
        You must make it absolutely clear that any such warranty, support, indemnity,
        or liability obligation is offered by You alone, and You hereby agree to indemnify
        every Contributor for any liability incurred by such Contributor as a result
        of warranty, support, indemnity or liability terms You offer. You may include
        additional disclaimers of warranty and limitations of liability specific to
        any jurisdiction.
        
           4. Inability to Comply Due to Statute or Regulation
        
        If it is impossible for You to comply with any of the terms of this License
        with respect to some or all of the Covered Software due to statute, judicial
        order, or regulation then You must: (a) comply with the terms of this License
        to the maximum extent possible; and (b) describe the limitations and the code
        they affect. Such description must be placed in a text file included with
        all distributions of the Covered Software under this License. Except to the
        extent prohibited by statute or regulation, such description must be sufficiently
        detailed for a recipient of ordinary skill to be able to understand it.
        
           5. Termination
        
        5.1. The rights granted under this License will terminate automatically if
        You fail to comply with any of its terms. However, if You become compliant,
        then the rights granted under this License from a particular Contributor are
        reinstated (a) provisionally, unless and until such Contributor explicitly
        and finally terminates Your grants, and (b) on an ongoing basis, if such Contributor
        fails to notify You of the non-compliance by some reasonable means prior to
        60 days after You have come back into compliance. Moreover, Your grants from
        a particular Contributor are reinstated on an ongoing basis if such Contributor
        notifies You of the non-compliance by some reasonable means, this is the first
        time You have received notice of non-compliance with this License from such
        Contributor, and You become compliant prior to 30 days after Your receipt
        of the notice.
        
        5.2. If You initiate litigation against any entity by asserting a patent infringement
        claim (excluding declaratory judgment actions, counter-claims, and cross-claims)
        alleging that a Contributor Version directly or indirectly infringes any patent,
        then the rights granted to You by any and all Contributors for the Covered
        Software under Section 2.1 of this License shall terminate.
        
        5.3. In the event of termination under Sections 5.1 or 5.2 above, all end
        user license agreements (excluding distributors and resellers) which have
        been validly granted by You or Your distributors under this License prior
        to termination shall survive termination.
        
           6. Disclaimer of Warranty
        
        Covered Software is provided under this License on an "as is" basis, without
        warranty of any kind, either expressed, implied, or statutory, including,
        without limitation, warranties that the Covered Software is free of defects,
        merchantable, fit for a particular purpose or non-infringing. The entire risk
        as to the quality and performance of the Covered Software is with You. Should
        any Covered Software prove defective in any respect, You (not any Contributor)
        assume the cost of any necessary servicing, repair, or correction. This disclaimer
        of warranty constitutes an essential part of this License. No use of any Covered
        Software is authorized under this License except under this disclaimer.
        
           7. Limitation of Liability
        
        Under no circumstances and under no legal theory, whether tort (including
        negligence), contract, or otherwise, shall any Contributor, or anyone who
        distributes Covered Software as permitted above, be liable to You for any
        direct, indirect, special, incidental, or consequential damages of any character
        including, without limitation, damages for lost profits, loss of goodwill,
        work stoppage, computer failure or malfunction, or any and all other commercial
        damages or losses, even if such party shall have been informed of the possibility
        of such damages. This limitation of liability shall not apply to liability
        for death or personal injury resulting from such party's negligence to the
        extent applicable law prohibits such limitation. Some jurisdictions do not
        allow the exclusion or limitation of incidental or consequential damages,
        so this exclusion and limitation may not apply to You.
        
           8. Litigation
        
        Any litigation relating to this License may be brought only in the courts
        of a jurisdiction where the defendant maintains its principal place of business
        and such litigation shall be governed by laws of that jurisdiction, without
        reference to its conflict-of-law provisions. Nothing in this Section shall
        prevent a party's ability to bring cross-claims or counter-claims.
        
           9. Miscellaneous
        
        This License represents the complete agreement concerning the subject matter
        hereof. If any provision of this License is held to be unenforceable, such
        provision shall be reformed only to the extent necessary to make it enforceable.
        Any law or regulation which provides that the language of a contract shall
        be construed against the drafter shall not be used to construe this License
        against a Contributor.
        
           10. Versions of the License
        
              10.1. New Versions
        
        Mozilla Foundation is the license steward. Except as provided in Section 10.3,
        no one other than the license steward has the right to modify or publish new
        versions of this License. Each version will be given a distinguishing version
        number.
        
              10.2. Effect of New Versions
        
        You may distribute the Covered Software under the terms of the version of
        the License under which You originally received the Covered Software, or under
        the terms of any subsequent version published by the license steward.
        
              10.3. Modified Versions
        
        If you create software not governed by this License, and you want to create
        a new license for such software, you may create and use a modified version
        of this License if you rename the license and remove any references to the
        name of the license steward (except to note that such modified license differs
        from this License).
        
        10.4. Distributing Source Code Form that is Incompatible With Secondary Licenses
        
        If You choose to distribute Source Code Form that is Incompatible With Secondary
        Licenses under the terms of this version of the License, the notice described
        in Exhibit B of this License must be attached. Exhibit A - Source Code Form
        License Notice
        
        This Source Code Form is subject to the terms of the Mozilla Public License,
        v. 2.0. If a copy of the MPL was not distributed with this file, You can obtain
        one at http://mozilla.org/MPL/2.0/.
        
        If it is not possible or desirable to put the notice in a particular file,
        then You may include the notice in a location (such as a LICENSE file in a
        relevant directory) where a recipient would be likely to look for such a notice.
        
        You may add additional accurate notices of copyright ownership.
        
        Exhibit B - "Incompatible With Secondary Licenses" Notice
        
        This Source Code Form is "Incompatible With Secondary Licenses", as defined
        by the Mozilla Public License, v. 2.0.
        
Project-URL: Homepage, https://github.com/bmwcarit/python-dlt
Classifier: Development Status :: 5 - Production/Stable
Classifier: License :: OSI Approved :: Mozilla Public License 2.0 (MPL 2.0)
Classifier: Intended Audience :: Developers
Classifier: Topic :: Software Development
Classifier: Topic :: System :: Logging
Classifier: Programming Language :: Python :: 3
Description-Content-Type: text/markdown
License-File: LICENCE.txt
Provides-Extra: dev
Requires-Dist: black>=22.10; extra == "dev"
Requires-Dist: flake8>=5; extra == "dev"
Requires-Dist: pytest-cov>=4.0.0; extra == "dev"
Requires-Dist: pytest>=7.2.0; extra == "dev"

# python-dlt

python-dlt is a thin Python ctypes wrapper around libdlt functions. It was
primarily created for use with BMW's test execution framework. However,
the implementation is independent and the API makes few assumptions about
the intended use.

Note: This is only tested with libdlt version v2.18.8 and v2.18.10,
later versions might require adaptations. The package will not support previous libdlt
versions from python-dlt v2.0. Also only GENIVI DLT daemon produced traces
have been tested.

## Design

The code is split up into 3 primary components:

* The `core`: This subpackage provides the major chunk of ctypes wrappers for
  the structures defined in libdlt. It abstracts out the libdlt structures for use
  by the rest of python-dlt. Classes defined here ideally should *not* be used
  outside of python-dlt. The module `core_base.py` provides the default
  implementation of the classes and the other `core_*.py` modules provide the
  overrides for the version specific implementations of libdlt. The correct version
  specific implementation will be loaded automatically at runtime. (the logic for
  this is in `core/__init__.py`)

* The python interface classes: These are defined in `dlt.py`. Most of the
  classes here derive from their corresponding ctypes class definitions from
  `core` and provide a more python friendly api/access to the underlying C/ctypes
  implementations. Ideally, python code using `python-dlt` would use these classes
  rather than the base classes in `core`.

* API for tools: This is the component that provides common interfaces required
  by the tools that use `python-dlt`, like the `DLTBroker`, 'DLTLifecycle' etc. These
  classes do not have equivalents in libdlt and were created based on usage
  requirements (and as such make assumptions about the manner in which they would
  be used).

If you're reading this document to work on the core or the python classes, it
would be a good idea to first understand the design of libdlt itself. This is
fairly well documented (look under the `doc/` directory of the `dlt-deamon` code
base). Of course the best reference is the code itself. `dlt-daemon` is written
in C and is a pretty well laid out, straight forward (ie: not many layers of
abstractions), small code base. Makes for good bedtime reading.

The rest of this document will describe and demonstrate some of the design of
the external API of python-dlt.

The classes most relevant for users of python-dlt possibly are `DLTClient`,
`DLTFile`, `DLTMessage`, `DLTBroker`. The names hopefully make their purpose
evident.

Here are examples of some interesting ways to use these classes:

* DLTFile and DLTMessage::

```python
    >>> from dlt import dlt
    >>> # DLTFile object can be obtained by loading a trace file
    >>> d = dlt.load("high_full_trace.dlt")
    >>> d.generate_index()      # Read the whole trace file and generate its index
    >>> print(d.counter_total)  # number of DLT messages in the file
    ...
    >>> print(d[0])             # messages can be indexed
    ...
    >>> for msg in d:           # DLTFile object is iterable
    ...     print(msg.apid)             # DLTMessage objects have all the attrs
    ...     print(msg.payload_decoded)  # one might expect from a DLT frame
    ...     print(msg)          # The str() of the DLTMessage closely matches the
    ...                         # output of dlt-receive
    >>> d[0] == d[-1]           # DLTMessage objects can be compared to each other
    >>> d.compare(dict(apid="SYS", citd="JOUR")) # ...or can be compared to an
    ...                                          # dict of attributes
    >>> import pickle
    >>> pickle.dumps(d[0])      # DLTMessage objects are (de)serializable using
    ...                         # the pickle protocol (this is to enable sharing
    ...                         # of the DLTMessage in a multiprocessing
    ...                         # environment)
```


* DLTClient and DLTBroker::

```python
    >>> from dlt import dlt
    >>> c = dlt.DLTClient(servIP="127.0.0.1")   # Only initializes the client
    >>> c.connect()                      # ...this connects
    >>> dlt.dltlib.dlt_receiver_receive(ctypes.byref(client.receiver), DLT_RECEIVE_SOCKET)  # receives data
    >>> c.read_message()                 # reads a single DLTMessage from received data  and returns it
    >>>
    >>> # more interesting is the DLTBroker class...
    >>> # - create an instance that initializes a DLTClient. Accepts a filename
    >>> #   where DLT traces would be stored
    >>> broker = DLTBroker(ip_address="127.0.0.1", filename='/tmp/testing_log.dlt')
    >>> # needs to be started and stopped explicitly and will create a run a
    >>> # DLTClient instance in a new *process*.
    >>> broker.start()
    >>> broker.stop()
    >>>
    >>> # Usually, used in conjunction with the DLTContext class from mtee
    >>> from mtee.testing.connectors.connector_dlt import DLTContext
    >>> broker = DLTBroker(ip_address="127.0.0.1", filename="/tmp/testing_log.dlt", verbose=True)
    >>> ctx = DLTContext(broker, filters=[("SYS", "JOUR")])
    >>> broker.start()
    >>> print(ctx.wait_for(count=10))
    >>>
```

## Design of DLTBroker

The DLTBroker abstracts out the management of 2 (multiprocessing) queues:

* The `message_queue`: This queue receives *all* messages from the DLT daemon
  (via a DLTClient instance, running as a separate process, code in
  `dlt.dlt_broker_handlers.DLTMessageHandler`) and stores them to a
  trace file.

* The `filter_queue`: This queue instructs the `DLTMessageHandler` which
  messages would be interesting at runtime, to be filtered and returned (for
  example, via a request from `DLTContext`). This is run as a separate thread in
  the `DLTBroker` process. The code for this is in
  `dlt.dlt_broker_handlers.DLTContextHandler`.

## Running tox on a local machine

In order to run tox command for this repository, please perform the following:

1. Build a docker image from the `Dockerfile` provided using:

```commandline
$ docker build -t python-dlt -f Dockerfile .
```

2. Run the tox in the docker container using:

```commandline
$ docker run -it --rm --volume $(pwd):/workspace python-dlt /bin/sh -xc "tox -e py3,lint"
```

3. [Special Case] Getting an interactive shell inside the docker container to run arbitrary commands:

```commandline
$ docker run -it --rm --volume $(pwd):/workspace --entrypoint sh python-dlt
```
