get_obj: add new extension (tilt-dev#483)

* feat: add remote_development Signed-off-by: Kobi Carmeli <[email protected]> * add to root readme file Signed-off-by: Kobi Carmeli <[email protected]> * refactor expose_ports Signed-off-by: Kobi Carmeli <[email protected]> * remove port exposure Signed-off-by: Kobi Carmeli <[email protected]> * delete call to expose_ports Signed-off-by: Kobi Carmeli <[email protected]> * rename to get_obj Signed-off-by: Kobi Carmeli <[email protected]> * fix test Signed-off-by: Kobi Carmeli <[email protected]> * fix test Signed-off-by: Kobi Carmeli <[email protected]> * fix test Signed-off-by: Kobi Carmeli <[email protected]> * fix test Signed-off-by: Kobi Carmeli <[email protected]> * fix test Signed-off-by: Kobi Carmeli <[email protected]> * fix test Signed-off-by: Kobi Carmeli <[email protected]> * debug test Signed-off-by: Kobi Carmeli <[email protected]> * update readme Signed-off-by: Kobi Carmeli <[email protected]> --------- Signed-off-by: Kobi Carmeli <[email protected]>
ianb-mp · Mar 13, 2023 · d16db1f · d16db1f
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diff --git a/README.md b/README.md
@@ -22,6 +22,7 @@ All extensions have been vetted and approved by the Tilt team.
 - [`earthly`](/earthly): Build container images using [earthly](https://earthly.dev)
 - [`execute_in_pod`](/execute_in_pod): Execute a command on a pod container.
 - [`file_sync_only`](/file_sync_only): No-build, no-push, file sync-only development. Useful when you want to live-reload a single config file into an existing public image, like nginx.
+- [`get_obj`](/get_obj): Get object yaml and the container's registry and image from an existing k8s resource such as deployment or statefulset
 - [`git_resource`](/git_resource): Deploy a dockerfile from a remote repository -- or specify the path to a local checkout for local development.
 - [`hasura`](/hasura): Deploys [Hasura GraphQL Engine](https://hasura.io/) and monitors metadata/migrations changes locally.
 - [`hello_world`](/hello_world): Print "Hello world!". Used in [Extensions](https://docs.tilt.dev/extensions.html).

diff --git a/get_obj/README.md b/get_obj/README.md
@@ -0,0 +1,64 @@
+# get obj
+
+Author: [Kobi Carmeli](https://github.com/kobik)
+
+Get object's yaml and image from an existing k8s resource such as deployment or statefulset.
+Develop, live update and debug against applications that were already deployed to Kubernetes from CI/CD or other tools.
+
+## `get_obj(name: str, kind: str, container_selector: str, namespace: str, disable_probes: bool)`
+- **name**: The object's name as you would express it to kubectl. e.g my-deployment.
+- **kind**: The object's kind. e.g 'deployment' or 'statefulset'
+- **container_selector**: The container name in the pod that will be used for remote development.
+- **namespace**?: The namespace of the object. If not specified, uses the current namespace.
+- **disable_probes**?: Disable liveness and readiness probes by removing them from the deployment, which is useful when debugging node applications. Default: False.
+
+### Example Usage
+```
+# Dockerfile.dev
+FROM node:18-alpine
+WORKDIR /app
+
+COPY ./app ./
+RUN npm ci
+
+CMD [ \
+  "npx", "nodemon", \
+  "--verbose", \
+  "--watch", ".", \
+  "--ext", "js" , \
+  "--signal", "SIGHUP", \
+  "--inspect", \
+  "index.js" \
+]
+```
+
+```
+# Tiltfile
+load('ext://get_obj', 'get_obj')
+
+# obj=struct(yaml, image, registry)
+obj=get_obj(
+  name='example-nodejs',
+  kind='deployment',
+  container_selector='my-container',
+  disable_probes=True
+)
+
+docker_build(obj.registry, '.',
+  live_update=[
+    sync('./app', '/app'),
+  ],
+  ...
+)
+
+k8s_yaml(yaml)
+
+k8s_resource(
+  name,
+  port_forwards=[
+    "8080:8080",
+    "9229:9229"
+  ],
+  ...
+)
+```
diff --git a/get_obj/Tiltfile b/get_obj/Tiltfile
@@ -0,0 +1,51 @@
+def get_container(decoded_yaml, container_selector):
+  containers=decoded_yaml["spec"]["template"]["spec"]["containers"]
+  found_containers=[]
+
+  for container in containers:
+    if container["name"] == container_selector:
+      return container
+
+    fail("failed to find container %s in the manifest %s" % (container_selector, containers))
+
+def get_image(container):
+  return container["image"]
+
+def remove_probe(container, probe):
+  if container.get(probe):
+    container.pop(probe)  
+
+def get_obj(name, kind, container_selector = None, namespace = None, disable_probes = False):
+  """
+  Enable remote developement and debugging environment on an exiting deployment.
+  It will redeploy the app using the given development Dockerfile, enable port-forwarding and disable healthcheck in order to enable remote debugging.
+  Both docker image build and port-forwarding can be replaced by your own docker_build and k8s_resource
+  Args:
+    name: The object's name as you would express it to kubectl. e.g my-deployment.
+    kind: The object's kind. e.g 'deployment' or 'statefulset'
+    container_selector: The container name in the pod that will be used for remote development.
+    namespace?: The namespace of the object. If not specified, uses the current namespace.
+    disable_probes?: Disable liveness and readiness probes by removing them from the deployment, which is useful when debugging node applications. Default: False.
+  """
+  args = ["kubectl", "get", "-o=yaml", '{}/{}'.format(kind, name)]
+  if namespace:
+    args.extend(["-n", namespace])
+
+  yaml=local(args, quiet=True)
+  decoded_yaml=decode_yaml(yaml)
+
+  if container_selector:
+    container=get_container(decoded_yaml, container_selector)
+    image=get_image(container)
+    registry=image.rsplit(":", 1)[0]
+  else:
+    image=None
+    registry=None
+
+  # disable probes
+  if container_selector and disable_probes:
+    remove_probe(container, "livenessProbe")
+    remove_probe(container, "readinessProbe")
+    yaml=encode_yaml(decoded_yaml)
+
+  return struct(yaml=yaml, image=image, registry=registry)
diff --git a/get_obj/test/.dockerignore b/get_obj/test/.dockerignore
@@ -0,0 +1,2 @@
+*
+!app
diff --git a/get_obj/test/Dockerfile b/get_obj/test/Dockerfile
@@ -0,0 +1,7 @@
+FROM node:18-alpine
+WORKDIR /app
+
+COPY ./app/ ./
+RUN npm ci
+
+CMD [ "node", "index.js" ]
diff --git a/get_obj/test/Dockerfile.dev b/get_obj/test/Dockerfile.dev
@@ -0,0 +1,16 @@
+FROM node:18-alpine
+WORKDIR /app
+
+COPY ./app ./
+RUN npm ci
+RUN echo "new image"
+
+CMD [ \
+  "npx", "nodemon", \
+  "--verbose", \
+  "--watch", ".", \
+  "--ext", "js" , \
+  "--signal", "SIGHUP", \
+  "--inspect", \
+  "index.js" \
+]
diff --git a/get_obj/test/Tiltfile b/get_obj/test/Tiltfile
@@ -0,0 +1,26 @@
+load('../Tiltfile', 'get_obj')
+
+name='example-nodejs'
+obj=get_obj(
+  name=name,
+  kind='deployment',
+  container_selector='my-container',
+  disable_probes=True
+)
+
+docker_build(obj.registry, '.',
+  dockerfile='Dockerfile.dev',
+  live_update=[
+    sync('./app', '/app'),
+  ]
+)
+
+k8s_yaml(obj.yaml)
+
+k8s_resource(
+  name,
+  port_forwards=[
+    "8080:8080",
+    "9229:9229"
+  ]
+)
diff --git a/get_obj/test/app/app.js b/get_obj/test/app/app.js
@@ -0,0 +1,14 @@
+const express = require('express');
+
+const app = express();
+
+app.get('/', function(req, res, next) {
+  res.send("cool!!!")
+});
+
+// catch 404 and forward to error handler
+app.use(function(req, res, next) {
+  next(createError(404));
+});
+
+module.exports = app;
diff --git a/get_obj/test/app/index.js b/get_obj/test/app/index.js
@@ -0,0 +1,13 @@
+const app = require('./app.js');
+
+const port = 8080;
+
+process.on('SIGHUP', () => {
+  process.exit()
+})
+process.on('SIGINT', () => {
+  process.exit()
+})
+app.listen(port, () => {
+  console.info('listening on port', 8080);
+})