Using Deta for python back-end

.github/workflows/backend.yml

@@ -12,13 +12,18 @@ jobs:
       - name: Checkout 🛎️
         uses: actions/checkout@v2
 
-      - name: Prepare Files 🔧
+      - name: Setup PDM 🔧
+        uses: pdm-project/setup-pdm@v3
+
+      - name: Export requirements.txt 🔧
         run: |
-          echo "nothing to do!"
+          cd back-end
+          make requirements.txt
 
       - name: Deploy 🚀
-        uses: peaceiris/[email protected].1
+        uses: BogDAAAMN/[email protected].1
         with:
-          publish_dir: ./back-end/
-          publish_branch: heroku
-          github_token: ${{ secrets.GITHUB_TOKEN }}
+          deta-access-token: ${{ secrets.DETA_TOKEN }}
+          deta-name: 'meldy'
+          deta-project: 'bubblefishstudio'
+          deta-project-dir: 'back-end'

back-end/.gitignore

@@ -1,2 +1,8 @@
 *.pyc
+build
+dist
+.venv
+.pdm.toml
+.deta
 profile.perf
+requirements.txt

back-end/app.py

@@ -0,0 +1 @@
+main.py

back-end/deta.json

@@ -0,0 +1,5 @@
+{
+  "name": "meldy",
+  "description": "melody generation back-end for the Meldy app",
+  "runtime": "python3.9"
+}

back-end/main.py

@@ -0,0 +1,43 @@
+from tempfile import NamedTemporaryFile
+from datetime import date
+from cProfile import Profile
+from os import environ
+
+from flask import Flask, Response, request
+from flask_cors import cross_origin
+import music21 as m21
+
+from meldy import MelodyGenerator
+
+app = Flask(__name__)
+
+@app.route("/")
+@cross_origin(["http://localhost:8080", "https://meldy.bubblefish.studio"])
+def make_melody():
+	valence = request.args.get("valence", default=1, type=float)
+	arousal = request.args.get("arousal", default=1, type=float)
+
+	if environ.get("PROFILE", False):
+		print("~~ profiling ~~")
+		pr = Profile()
+		pr.enable()
+
+	mg = MelodyGenerator(valence, arousal)
+	m = mg.gen_melody()
+
+	if environ.get("PROFILE", False):
+		pr.disable()
+		print("~~ end profile ~~")
+		pr.dump_stats("profile.perf")
+
+	# TODO: move this where appropriate maybe
+	meta = m21.metadata.Metadata()
+	meta.title = "Mood of the day" # TODO: maybe we can generate random titles
+	meta.composer = "Meldy"
+	meta.date = date.today().strftime("%Y/%m/%d")
+	m.metadata = meta
+
+	with NamedTemporaryFile() as t:
+		m.write("musicxml", fp=t.name)
+		t.seek(0)
+		return Response(t.read(), mimetype="application/vnd.recordare.musicxml")

back-end/makefile

@@ -0,0 +1,10 @@
+.PHONY: deploy
+
+requirements.txt: pdm.lock
+	pdm export --without-hashes -o $@
+	# pdm adds --index-url, but deta can't parse it correctly
+	# so we need to remove it
+	sed -i '' '/^--index-url/d' $@
+
+deploy: requirements.txt
+	deta deploy

back-end/meldy/__init__.py

@@ -0,0 +1 @@
+from .melody import MelodyGenerator