• Transformer API ** Background

  The idea for this project comes from [[https://twitter.com/bsaeta][Brennan Saeta]] at the [[https://www.tryswift.co/events/2019/sanjose/][try! Swift San Jose 2019 conference]].

  The project is an example API server wrapping a Swift for TensorFlow model, particularly the [[https://github.com/tensorflow/swift-models/tree/master/Transformer][Swift for TensorFlow implementation of OpenAI's GPT-2 Transformer language model]].

** Prerequisites

• Install [[https://github.com/tensorflow/swift/blob/master/Installation.md#development-snapshots][latest development snapshot of Swift for TensorFlow]]

• Install Python 3

NOTE: This project was compiled on Ubuntu 19.04 with the nightly snapshot of Swift for TensorFlow as of [2019-06-06 Thu].

** Setup Python + Ensure Swift for TensorFlow models compile

#+begin_src sh

Build models

mkdir -p ~/code/swift-source cd ~/code/swift-source git clone https://github.com/tensorflow/swift-models cd swift-models

https://github.com/tensorflow/swift-models/blob/master/README.md#build

swift build -v -Xlinker -ltensorflow

https://colab.research.google.com/github/tensorflow/swift/blob/master/docs/site/tutorials/python_interoperability.ipynb

export PYTHON_LIBRARY=/usr/lib/x86_64-linux-gnu/libpython3.7m.so.1.0

sudo apt install python3-pip pip3 install regex numpy

cd Transformer ./main 0.5 "My name is" #+end_src

** Serve API

Terminal 1 : Start server

#+begin_src sh

Switch to this repo

cd Sources/TransformerAPI/ bash download_model.sh 345M

cd ../.. swift build swift run TransformerAPI #+end_src

Terminal 2 : Run client

#+begin_src sh

curl http://localhost:8888/blabber -d "I'm at a conference" && echo
#+end_src

Example results:

#+BEGIN_EXAMPLE

with the US Congress on climate change, and I'm talking about the Paris Agreement, which is the main signatory to the Copenhagen Accord. And I think it's important to understand that the Paris Agreement is not a treaty, it's a treaty on climate change.

I think it's important to understand that the Paris Agreement is not a treaty on climate change.

The Paris Agreement is not a treaty on climate change.

And I think that's the kind of thing that we #+END_EXAMPLE

** FAQ

*** Why swift-nio? Why not Vapor or Kitura?

Because both projects were not ready for Swift 5 & Ubuntu 19.04, as of [2019-06-07 Fri]. At least, I couldn't get them working.

Whereas I /was/ able to get a simple swift-nio based http server, thanks to the [[https://github.com/apple/swift-nio/blob/dfe4318c503bdc959e97ddfb2f7ed1d0f399f8f9/Sources/NIOHTTP1Server/main.swift][example code]] & help from [[https://twitter.com/johannesweiss/status/1137024265356578816][actual engineers who work at Apple on swift-nio]] who were present for try! Swift San Jose 2019 :).