65 lines
3.1 KiB
Markdown
65 lines
3.1 KiB
Markdown
# GoTelem: Golang-based telemetry tools
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`GoTelem` is a toolkit and library to make working with solar car telemetry
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data fast, reliable, and insightful.
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Features:
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- SocketCAN interface for connecting to physical hardware.
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- TCP streaming system based around MessagePack-RPC for LAN control/inspection.
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- XBee integration and control for long-range communication.
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- HTTP API for easy external tool integration.
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`GoTelem` provides a flexible system for ingesting, storing, analyzing, and distributing
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telemetry information.
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## Rationale
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There are probably two questions:
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1. Why a telemetry library that runs on an OS?
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2. Why is it written in Go?
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To answer the first question, the needs of the telemetry board are ill-suited for a microcontroller
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since it requires doing multiple non-trivial tasks in parallel. The on-car system must ingest
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all can packets, write them to disk, and then transmit them over XBee if they match a filter.
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Doing fast disk I/O is difficult.
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There are also significant advantages to moving to using a Linux system for telemetry. We gain
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Wifi/Bluetooth/network support easily, we can integrate USB devices like a USB GPS reciever,
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and we can share common tooling between the car code and the receiver code.
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I chose to write this in Go because Go has good concurrency support, good cross-compilation,
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and relatively good performance.
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C/C++ was eliminated due to being too close to the metal and having bad tooling/cross compilation.
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Python was eliminated due to having poor concurrency support and difficult packaging/distribution.
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It also lacks a good http/networking story, instead relying on WSGI/ASGI packages which
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make Windows not viable. Futhermore, being dynamically typed leads to issues in asserting
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robustness of the code.
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Rust was elminiated due to being too different from more common programming languages. Likewise
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for F#, C#, D, Zig, Nim, Julia, Racket, Elixr, and Common Lisp. Yes, I did seriouisly consider each
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of these.
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Go has some quirks and -isms, like lacking "true" Object-Orientation, but the language is designed
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around being normal to look at, easy to write, and straightforward to understand.
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Go has really good cross compilation support built in to the `go` binary. However, since this
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package uses some C libraries (SQLite), certain functionality will be missing if you don't
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have a cross-compiler set up. There's a way to make things easier on Linux
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[using `zig cc`](https://zig.news/kristoff/building-sqlite-with-cgo-for-every-os-4cic)
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but this is not usually important since the user can pretty easily compile it on their
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own system, and it's a single executable to share to others with the same OS/architecture.
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## Building
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`gotelem` was designed to be all-inclusive while being easy to build and have good cross-platform support. Binaries are a single,
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statically linked file that can be shared to other users of the same OS. Certain features, like socketCAN support, are only enabled on platforms that
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support them (Linux). This is handled automatically; builds will exclude the socketCAN files and the additional commands and features will not be present in the CLI.
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