feat: backend hot reload with skaffold

Author: osintalex

chart/templates/backend.yaml

@@ -55,6 +55,12 @@ spec:
         - name: api
           image: {{ .Values.backend_image }}
           imagePullPolicy: {{ .Values.backend_pull_policy }}
+          {{- if .Values.backend_api_command_override }}
+          command:
+            {{- range .Values.backend_api_command_override }}
+            - {{ . | quote }}
+            {{- end }}
+          {{- else }}
           command:
               - gunicorn
               - btrixcloud.main:app_root
@@ -66,6 +72,7 @@ spec:
               - "{{ .Values.backend_workers | default 1 }}"
               - --worker-class
               - uvicorn.workers.UvicornWorker
+          {{- end }}
 
           envFrom:
             - configMapRef:

docs/develop/backend-hot-reload.md

@@ -0,0 +1,27 @@
+# Deploy the Backend with Hot Reloading
+
+This guide explains how to deploy Browsertrix with [skaffold](https://skaffold.dev/) so the backend hot reloads. This
+may save you time since you don't need to rebuild the backend container every time you change code.
+
+## Requirements
+
+Follow the documentation to [install skaffold](https://skaffold.dev/docs/install/), i.e. if you are on
+Mac OS run:
+
+```sh
+brew install skaffold
+```
+
+To install helm and set up a local Kubernetes cluster, see the section on [local dev set up](local-dev-setup.md).
+
+## Quickstart
+
+From the command line, run:
+
+```sh
+skaffold dev
+```
+
+This will deploy Browsertrix into the cluster and port forward the API with hot reloading. 
+Navigate to `localhost:8000/api/redoc` to see the documentation.
+Changing any code in `backend/btrixcloud` will trigger a reload.

docs/develop/frontend-dev.md

@@ -72,6 +72,12 @@ If connecting to a local deployment cluster, set `API_BASE_URL` to:
 API_BASE_URL=http://localhost:30870
 ```
 
+If the API is not running at `localhost:30870`, port forward it from your local cluster:
+
+```sh
+kubectl port-forward svc/browsertrix-cloud-backend 30870:8000
+```
+
 ??? info "Port when using Minikube (on macOS)"
 
     When using Minikube on macOS, the port will not be 30870. Instead, Minikube opens a tunnel to a random port,
@@ -85,7 +91,7 @@ Start the frontend development server:
 yarn start
 ```
 
-This will open `localhost:9870` in a new tab in your default browser.
+This will open `localhost:9870` in a new tab in your default browser. It will take a few minutes to finish.
 
 Saving changes to files in `src` will automatically reload your browser window with the latest UI updates.
 

docs/develop/local-dev-setup.md

@@ -116,7 +116,7 @@ helm upgrade --install -f ./chart/values.yaml \
 
     ??? info "MicroK8S"
 
-        If using microk8s, the commend will be:
+        If using microk8s, the command will be:
 
         ```sh
         microk8s helm3 upgrade --install -f ./chart/values.yaml -f ./chart/local.yaml btrix ./chart/
@@ -133,3 +133,7 @@ Changes to settings in `./chart/local.yaml` can be deployed with `helm upgrade .
 ## Deploying Frontend Only
 
 If you are just making changes to the frontend, you can also [deploy the frontend separately](frontend-dev.md) using a dev server for quicker iteration.
+
+## Deploying Backend with Hot Reloading
+
+If you want to iterate faster on the backend, read [deploy the backend with hot reloading](backend-hot-reload.md).

mkdocs.yml

@@ -63,6 +63,7 @@ nav:
       - develop/local-dev-setup.md
       - develop/frontend-dev.md
       - develop/docs.md
+      - develop/backend-hot-reload.md
   - User Guide:
       - user-guide/index.md
       - user-guide/signup.md

skaffold.yaml

@@ -4,6 +4,8 @@ metadata:
   name: browsertrix
 build:
   artifacts:
+    # only put the backend in here since it's quite easy now
+    # to run frontend locally and get hot reloading with yarn
     - image: docker.io/webrecorder/browsertrix-backend
       context: backend
       docker:
@@ -12,25 +14,33 @@ build:
         manual:
         - src: 'btrixcloud/**/*'
           dest: .
-    - image: docker.io/webrecorder/browsertrix-frontend
-      context: frontend
-      docker:
-        dockerfile: Dockerfile
-      sync:
-        manual:
-        - src: 'src/**/*'
-          dest: .
+portForward:
+- resourceType: service
+  resourceName: browsertrix-cloud-backend
+  # assumes you are doing local dev in `default` namespace
+  # if you aren't you need to change this manually
+  namespace: default
+  port: 8000
+  localPort: 8000
 deploy:
   helm:
     releases:
       - name: btrix
         chartPath: chart
         valuesFiles:
           - chart/values.yaml
-          # local must come after since it overrides stuff in values.yaml
-          - chart/local.yaml
         # See https://skaffold.dev/docs/deployers/helm/
         # must do this to make skaffold use local images with helm
         setValues:
           backend_image: docker.io/webrecorder/browsertrix-backend
-          frontend_image: docker.io/webrecorder/browsertrix-frontend
+          backend_pull_policy: "Never"
+          # hot reloading doesn't work with default gunicorn command
+          # so need to override to use uvicorn
+          backend_api_command_override: 
+            - uvicorn
+            - btrixcloud.main:app_root
+            - --reload
+            - --host
+            - "0.0.0.0"
+            - --port
+            - "8000"