Feature: Implement connected-mode operation

.coveragerc

@@ -1,3 +1,6 @@
 [run]
 branch=true
 source=aioax25
+omit=
+    tests
+    aioax25/tools/**

.gitignore

@@ -5,7 +5,8 @@ __pycache__
 *.egg-info
 *.pyc
 .coverage
-coverage/
+aioax25.egg-info/
+cover/
 testreports.xml
 dist/
 build/

README.md

@@ -7,20 +7,6 @@ The aim of this project is to implement a simple-to-understand asynchronous
 AX.25 library built on `asyncio` and `pyserial`, implementing a AX.25 and APRS
 stack in pure Python.
 
-## Python 3.5+ and above is required as of 2021-11-12
-
-I did try to support 3.4, but this proved to be infeasible for the following
-reasons:
-
-* Python 3.8+ makes `asyncio.coroutine` deprecated (apparently will be removed
-  in 3.10).  This meant I needed `coroutine` and `async def` versions of some
-  API functions, and the necessary logic to "hide" the latter from Python 3.4.
-* Trying to coax generator-based coroutines to run "in the background" for unit
-  test purposes proved to be a pain in the arse.
-
-Python 3.5 support is planned to continue until it too, becomes infeasible
-(e.g. if type annotations become required).
-
 ## What works
 
 * We can put a Kantronics KPC-3 TNC into KISS mode automatically
@@ -29,27 +15,30 @@ Python 3.5 support is planned to continue until it too, becomes infeasible
   [NWDR UDRC-II](https://nw-digital-radio.groups.io/g/udrc/wiki/home))
 * We can receive AX.25 UI frames
 * We can send AX.25 UI frames
+* Connecting to AX.25 nodes (*experimental*)
+* Accepting connections from AX.25 nodes (*experimental*)
 
 ## What doesn't work
 
-* Connecting to AX.25 nodes
-* Accepting connections from AX.25 nodes
+* Nothing yet?
 
 ## What isn't tested
 
 * Platforms other than GNU/Linux
 
 ## Current plans
 
-Right now, I intend to get enough going for APRS operation, as that is my
-immediate need now.  Hence the focus on UI frames.
+Right now, I have the smarts to deal with basic APRS messaging.  Hence the
+focus on UI frames.  We can send and receive APRS message frames, parse some
+kinds of position frames, and do basic UI frame stuff.
 
-I intend to write a core class that will take care of some core AX.25 message
-handling work and provide the basis of what's needed to implement APRS.
+Preliminary support for AX.25 connected mode is present, but is _experimental_.
+It was tested connecting to a BPQ32 node, and being connected to by a BPQ32
+node, but not a lot of testing has been done at this stage.  **More feedback
+would be appreciated.**  The API is also very much a work-in-progress.
 
 After that, some things I'd like to tackle in no particular order:
 
-* Connected mode operation
 * NET/ROM support
 
 Supported platforms will be GNU/Linux, and possibly BSD variants.  I don't
@@ -314,3 +303,11 @@ The `APRSDigipeater` class constructor can take a single parameter,
 `digipeater_timeout`, which sets an expiry (default of 5 seconds) on queued
 digipeat messages.  If a message is not sent by the time this timeout expires,
 the message is quietly dropped, preventing the memory effect.
+
+## Specifications
+
+This library is built on the following specifications:
+
+* [AX.25 2.0](https://htmlpreview.github.io/?https://github.com/sjlongland/aioax25/blob/feature/connected-mode/doc/ax25-2p0/index.html)
+* [AX.25 2.2](doc/ax25-2p2/ax25-2p2.pdf)
+* [APRS 1.01](http://www.aprs.org/doc/APRS101.PDF)

aioax25/aprs/aprs.py

@@ -78,7 +78,6 @@ def __init__(
         # Logger instance
         log=None,
     ):
-
         super(APRSRouter, self).__init__()
         if log is None:
             log = logging.getLogger(self.__class__.__module__)

aioax25/aprs/datatype.py

@@ -13,28 +13,30 @@ class APRSDataType(Enum):
     not including unused or reserved types.  Page 17 of APRS 1.0.1 spec.
     """
 
-    MIC_E_BETA0 = 0x1C
-    MIC_E_OLD_BETA0 = 0x1D
-    POSITION = ord("!")
-    PEET_BROS_WX1 = ord("#")
-    RAW_GPRS_ULT2K = ord("$")
-    AGRELO_DFJR = ord("%")
-    RESERVED_MAP = ord("&")
-    MIC_E_OLD = ord("'")
-    ITEM = ord(")")
-    PEET_BROS_WX2 = ord("*")
-    TEST_DATA = ord(",")
-    POSITION_TS = ord("/")
-    MESSAGE = ord(":")
-    OBJECT = ord(";")
-    STATIONCAP = ord("<")
-    POSITION_MSGCAP = ord("=")
-    STATUS = ord(">")
-    QUERY = ord("?")
+    # fmt: off
+    MIC_E_BETA0        = 0x1C
+    MIC_E_OLD_BETA0    = 0x1D
+    POSITION           = ord("!")
+    PEET_BROS_WX1      = ord("#")
+    RAW_GPRS_ULT2K     = ord("$")
+    AGRELO_DFJR        = ord("%")
+    RESERVED_MAP       = ord("&")
+    MIC_E_OLD          = ord("'")
+    ITEM               = ord(")")
+    PEET_BROS_WX2      = ord("*")
+    TEST_DATA          = ord(",")
+    POSITION_TS        = ord("/")
+    MESSAGE            = ord(":")
+    OBJECT             = ord(";")
+    STATIONCAP         = ord("<")
+    POSITION_MSGCAP    = ord("=")
+    STATUS             = ord(">")
+    QUERY              = ord("?")
     POSITION_TS_MSGCAP = ord("@")
-    TELEMETRY = ord("T")
-    MAIDENHEAD = ord("[")
-    WX = ord("_")
-    MIC_E = ord("`")
-    USER_DEFINED = ord("{")
-    THIRD_PARTY = ord("}")
+    TELEMETRY          = ord("T")
+    MAIDENHEAD         = ord("[")
+    WX                 = ord("_")
+    MIC_E              = ord("`")
+    USER_DEFINED       = ord("{")
+    THIRD_PARTY        = ord("}")
+    # fmt: on

aioax25/aprs/message.py

@@ -176,7 +176,6 @@ def _enter_state(self, state):
 
 
 class APRSMessageFrame(APRSFrame):
-
     MSGID_RE = re.compile(r"{([0-9A-Za-z]+)(}[0-9A-Za-z]*)?(\r?)$")
     ACKREJ_RE = re.compile(r"^(ack|rej)([0-9A-Za-z]+)$")
 
@@ -259,7 +258,6 @@ def __init__(
         cr=True,
         src_cr=None,
     ):
-
         self._addressee = AX25Address.decode(addressee).normalised
         self._msgid = msgid
         self._replyack = replyack