NAS-129755 / 25.04 / Introduce docstrings and type annotations (#7)

* add readme and pytype CI

* manual merge prep

* silence CI import error

* fix CI

* fix CI

* import `ErrnoMixin` for middlewared.service_exception

.github/workflows/pytype.yml

@@ -0,0 +1,27 @@
+name: "pytype"
+
+on:
+  pull_request:
+    types:
+      - 'synchronize'
+      - 'opened'
+
+jobs:
+  type-check:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v3
+    - name: Setup Python
+      uses: actions/setup-python@v4
+      with:
+        python-version: 3.11
+
+    - name: Install Dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install pytype websocket-client
+
+    - name: Type-Check
+      run: pytype -j auto .

README.md

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+<p align="center">
+      <a href="https://discord.gg/Q3St5fPETd"><img alt="Join Discord" src="https://badgen.net/discord/members/Q3St5fPETd/?icon=discord&label=Join%20the%20TrueNAS%20Community" /></a>
+ <a href="https://www.truenas.com/community/"><img alt="Join Forums" src="https://badgen.net/badge/Forums/Post%20Now//purple" /></a> 
+ <a href="https://jira.ixsystems.com"><img alt="File Issue" src="https://badgen.net/badge/Jira/File%20Issue//red?icon=jira" /></a>
+</p>
+
+# TrueNAS Websocket Client
+
+*Found an issue? Please report it on our [Jira bugtracker](https://jira.ixsystems.com).*
+
+## About
+
+The TrueNAS websocket client provides the command line tool `midclt` and the means to easily communicate with [middleware](https://github.com/truenas/middleware) using Python by making calls through the [websocket API](https://www.truenas.com/docs/api/scale_websocket_api.html). The client can connect to a local TrueNAS instance by default or to a specified remote socket. This offers an alternative to going through the [web UI](https://github.com/truenas/webui) or connecting via ssh.
+
+By default, communication facilitated by the API between the client and middleware now uses the [JSON-RPC 2.0](https://www.jsonrpc.org/specification) protocol. However, it is still possible to use the legacy client by passing a legacy uri, e.g. `'ws://some.truenas.address/websocket'` as opposed to `'ws://some.truenas.address/api/current'`.
+
+## Getting Started
+
+TrueNAS comes with this client preinstalled, but it is also possible to use the TrueNAS websocket client from a non-TrueNAS host.
+
+On a non-TrueNAS host, ensure that Git is installed and run `pip install git+https://github.com/truenas/api_client.git` to automatically install dependencies. You may alternatively clone this repository and run `python setup.py install`. Using a Python venv is recommended.
+
+## Usage
+
+The `midclt` command (not to be confused with the [TrueNAS CLI](https://github.com/truenas/midcli)) provides a way to make direct API calls through the client. To view its syntax, enter `midclt -h`. The `-h` option can also be used with any of `midclt`'s subcommands.
+
+The client's default behavior is to connect to the localhost's middlewared socket. For a remote connection, e.g. from a Windows host, you must specify the `--uri` option and authenticate with either user credentials or an API key. For example: `midclt --uri ws://<TRUENAS_IP>/api/current -K key ...`
+
+### Make local API calls
+
+```
+root@my_truenas[~]# midclt call user.create '{"full_name": "John Doe", "username": "user", "password": "pass", "group_create": true}'
+```
+
+### Login to a remote TrueNAS
+
+```
+root@my_truenas[~]# midclt --uri ws://some.other.truenas/api/current -U user -P password call system.info
+```
+
+### Start a job
+
+```
+root@my_truenas[~]# midclt call -j pool.dataset.lock mypool/mydataset
+```
+
+## Development
+
+The TrueNAS API client can also be used in Python scripts.
+
+### Make local API calls
+
+```python
+from truenas_api_client import Client
+
+with Client() as c:  # Local IPC
+      print(c.ping())  # pong
+      user = {"full_name": "John Doe", "username": "user", "password": "pass", "group_create": True}
+      entry_id = c.call("user.create", user)
+      user = c.call("user.get_instance", entry_id)
+      print(user["full_name"])  # John Doe
+```
+
+### Login with a user account or an API key
+
+```python
+# User account
+with Client(uri="ws://some.other.truenas/api/current") as c:
+      c.call("auth.login", username, password)
+
+# API key
+with Client(uri="ws://some.other.truenas/api/current") as c:
+      c.call("auth.login_with_api_key", key)
+```
+
+### Start a job
+
+```python
+with Client() as c:
+      is_locked = c.call("pool.dataset.lock", "mypool/mydataset", job=True)
+      if is_locked:
+            args = {"datasets": [{"name": "mypool/mydataset", "passphrase": "passphrase"}]}
+            c.call("pool.dataset.unlock", "mypool/mydataset", args, job=True)
+```
+
+## Helpful Links
+
+<a href="https://truenas.com">
+<img align="right" src="https://www.truenas.com/docs/images/TrueNAS_Open_Enterprise_Storage.png" />
+</a>
+
+- [Websocket API docs](https://www.truenas.com/docs/api/scale_websocket_api.html)
+- [Middleware repo](https://github.com/truenas/middleware)
+- [Official TrueNAS Documentation Hub](https://www.truenas.com/docs/)
+- [Get started building TrueNAS Scale](https://github.com/truenas/scale-build)
+- [Forums](https://www.truenas.com/community/)