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Posted to commits@beam.apache.org by al...@apache.org on 2019/10/07 19:58:03 UTC
[beam] branch master updated: Custom container docs
This is an automated email from the ASF dual-hosted git repository.
altay pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/beam.git
The following commit(s) were added to refs/heads/master by this push:
new 1cc27c3 Custom container docs
new 1df2e6c Merge pull request #9607 from soyrice/sdk_2-16_docs-updates
1cc27c3 is described below
commit 1cc27c3c0ac3b011dada48ebf69db8f8501dfbaa
Author: Cyrus Maden <cm...@google.com>
AuthorDate: Wed Sep 18 10:27:25 2019 -0400
Custom container docs
Remove old containers doc
Update links
Pushing to Bintray
Resolve comments
Fix broken links
Remove extra line break
---
sdks/CONTAINERS.md | 191 ---------------------
.../src/_includes/section-menu/documentation.html | 10 +-
website/src/_posts/2019-09-04-gsoc-19.md | 2 +-
website/src/documentation/index.md | 2 +-
.../documentation/resources/learning-resources.md | 2 +-
website/src/documentation/runtime/environments.md | 183 ++++++++++++++++++++
.../{execution-model.md => runtime/model.md} | 10 +-
.../transforms/python/element-wise/pardo.md | 2 +-
8 files changed, 202 insertions(+), 200 deletions(-)
diff --git a/sdks/CONTAINERS.md b/sdks/CONTAINERS.md
deleted file mode 100644
index e5461c1..0000000
--- a/sdks/CONTAINERS.md
+++ /dev/null
@@ -1,191 +0,0 @@
-<!--
- Licensed to the Apache Software Foundation (ASF) under one
- or more contributor license agreements. See the NOTICE file
- distributed with this work for additional information
- regarding copyright ownership. The ASF licenses this file
- to you under the Apache License, Version 2.0 (the
- "License"); you may not use this file except in compliance
- with the License. You may obtain a copy of the License at
-
- http://www.apache.org/licenses/LICENSE-2.0
-
- Unless required by applicable law or agreed to in writing,
- software distributed under the License is distributed on an
- "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- KIND, either express or implied. See the License for the
- specific language governing permissions and limitations
- under the License.
--->
-
-# Docker containers
-
-The Beam [portability effort](https://s.apache.org/beam-fn-api) aims to make it possible
-for any SDK to work with any runner. One aspect of the effort is the isolation of the SDK
-and user code execution environment from the runner execution environment using
-[docker](https://www.docker.com/), as defined in the portability
-[container contract](https://s.apache.org/beam-fn-api-container-contract).
-
-This document describes how to build and push container images to that end. The push
-step generally requires an account with a public docker registry, such
-as [bintray.io](bintray.io) or
-[Google Container Registry](https://cloud.google.com/container-registry). These
-instructions assume familiarity with docker and a bintray account under the
-current username with a docker repository named "apache".
-
-## How to build container images
-
-**Prerequisites**: install [docker](https://www.docker.com/) on your
-platform. You can verify that it works by running `docker images` or any other
-docker command.
-
-Run Gradle with the `docker` target:
-
-```
-$ pwd
-[...]/beam
-$ ./gradlew docker
-[...]
-> Task :sdks:python:container:docker
-a571bb44bc32: Verifying Checksum
-a571bb44bc32: Download complete
-aa6d783919f6: Verifying Checksum
-aa6d783919f6: Download complete
-f2b6b4884fc8: Verifying Checksum
-f2b6b4884fc8: Download complete
-f2b6b4884fc8: Pull complete
-74eaa8be7221: Pull complete
-2d6e98fe4040: Pull complete
-414666f7554d: Pull complete
-bb0bcc8d7f6a: Pull complete
-a571bb44bc32: Pull complete
-aa6d783919f6: Pull complete
-Digest: sha256:d9455be2cc68ded908084ec5b63a5cbb87f12ec0915c2f146751bd50b9aef01a
-Status: Downloaded newer image for python:2
- ---> 2863c80c418c
-Step 2/6 : MAINTAINER "Apache Beam <de...@beam.apache.org>"
- ---> Running in c787617f4af1
-Removing intermediate container c787617f4af1
- ---> b4ffbbf94717
-[...]
- ---> a77003ead1a1
-Step 5/6 : ADD target/linux_amd64/boot /opt/apache/beam/
- ---> 4998013b3d63
-Step 6/6 : ENTRYPOINT ["/opt/apache/beam/boot"]
- ---> Running in 30079dc4204b
-Removing intermediate container 30079dc4204b
- ---> 4ea515403a1a
-Successfully built 4ea515403a1a
-Successfully tagged herohde-docker-apache.bintray.io/beam/python:latest
-[...]
-```
-
-Note that the container images include built content, including the Go boot
-code. Some images, notably python, take a while to build, so building just
-the specific images needed can be a lot faster:
-
-```
-$ ./gradlew -p sdks/java/container docker
-$ ./gradlew -p sdks/python/container docker
-$ ./gradlew -p sdks/go/container docker
-```
-
-**(Optional)** When built, you can see, inspect and run them locally:
-
-```
-$ docker images
-REPOSITORY TAG IMAGE ID CREATED SIZE
-herohde-docker-apache.bintray.io/beam/python latest 4ea515403a1a 3 minutes ago 1.27GB
-herohde-docker-apache.bintray.io/beam/java latest 0103512f1d8f 34 minutes ago 780MB
-herohde-docker-apache.bintray.io/beam/go latest ce055985808a 35 minutes ago 121MB
-[...]
-```
-
-Despite the names, these container images live only on your local machine.
-While we will re-use the same tag "latest" for each build, the
-images IDs will change.
-
-**(Optional)**: the default setting for `docker-repository-root` specifies the above bintray
-location. You can override it by adding:
-
-```
--Pdocker-repository-root=<location>
-```
-
-Similarly, if you want to specify a specific tag instead of "latest", such as a "2.3.0"
-version, you can do so by adding:
-
-```
--Pdocker-tag=<tag>
-```
-
-### Adding dependencies, and making Python go vroom vroom
-
-Not all dependencies are like insurance on used Vespa, if you don't have them some job's just won't run at all and you can't sweet talk your way out of a tensorflow dependency. On the other hand, for Python users dependencies can be automatically installed at run time on each container, which is a great way to find out what your systems timeout limits are. Regardless as to if you have dependency which isn't being installed for you and you need, or you just don't want to install tensorflo [...]
-
-For Python we have a sample Dockerfile which will take the user specified requirements and install them on top of your base image. If your building from source follow the directions above, otherwise you can set the environment variable BASE_PYTHON_CONTAINER_IMAGE to the desired released version.
-
-```
-USER_REQUIREMENTS=~/my_req.txt ./sdks/python/scripts/add_requirements.sh
-```
-
-Once your custom container is built, remember to upload it to the registry of your choice.
-
-If you build a custom container when you run your job you will need to specify instead of the default latest container, so for example Holden would specify:
-
-```
---worker_harness_container_image=holden-docker-apache.bintray.io/beam/python-with-requirements
-```
-
-## How to push container images
-
-**Preprequisites**: obtain a docker registry account and ensure docker can push images to it,
-usually by doing `docker login` with the appropriate information. The image you want
-to push must also be present in the local docker image repository.
-
-For the Python SDK harness container image, run:
-
-```
-$ docker push $USER-docker-apache.bintray.io/beam/python:latest
-The push refers to repository [herohde-docker-apache.bintray.io/beam/python]
-723b66d57e21: Pushed
-12d5806e6806: Pushed
-b394bd077c6e: Pushed
-ca82a2274c57: Pushed
-de2fbb43bd2a: Pushed
-4e32c2de91a6: Pushed
-6e1b48dc2ccc: Pushed
-ff57bdb79ac8: Pushed
-6e5e20cbf4a7: Pushed
-86985c679800: Pushed
-8fad67424c4e: Pushed
-latest: digest: sha256:86ad57055324457c3ea950f914721c596c7fa261c216efb881d0ca0bb8457535 size: 2646
-```
-
-Similarly for the Java and Go SDK harness container images. If you want to push the same image
-to multiple registries, you can retag the image using `docker tag` and push.
-
-**(Optional)** On any machine, you can now pull the pushed container image:
-
-```
-$ docker pull $USER-docker-apache.bintray.io/beam/python:latest
-latest: Pulling from beam/python
-f2b6b4884fc8: Pull complete
-4fb899b4df21: Pull complete
-74eaa8be7221: Pull complete
-2d6e98fe4040: Pull complete
-414666f7554d: Pull complete
-bb0bcc8d7f6a: Pull complete
-a571bb44bc32: Pull complete
-aa6d783919f6: Pull complete
-7255d71dee8f: Pull complete
-08274803455d: Pull complete
-ef79fab5686a: Pull complete
-Digest: sha256:86ad57055324457c3ea950f914721c596c7fa261c216efb881d0ca0bb8457535
-Status: Downloaded newer image for herohde-docker-apache.bintray.io/beam/python:latest
-$ docker images
-REPOSITORY TAG IMAGE ID CREATED SIZE
-herohde-docker-apache.bintray.io/beam/python latest 4ea515403a1a 35 minutes ago 1.27 GB
-[...]
-```
-
-Note that the image IDs and digests match their local counterparts.
diff --git a/website/src/_includes/section-menu/documentation.html b/website/src/_includes/section-menu/documentation.html
index 0a56d8c..529c264e 100644
--- a/website/src/_includes/section-menu/documentation.html
+++ b/website/src/_includes/section-menu/documentation.html
@@ -12,7 +12,6 @@
<li><span class="section-nav-list-main-title">Documentation</span></li>
<li><a href="{{ site.baseurl }}/documentation">Using the Documentation</a></li>
-<li><a href="{{ site.baseurl }}/documentation/execution-model">Beam Execution Model</a></li>
<li>
<span class="section-nav-list-title">Pipeline development lifecycle</span>
@@ -256,6 +255,15 @@
</li>
<li class="section-nav-item--collapsible">
+ <span class="section-nav-list-title">Runtime systems</span>
+
+ <ul class="section-nav-list">
+ <li><a href="{{ site.baseurl }}/documentation/runtime/model/">Execution model</a></li>
+ <li><a href="{{ site.baseurl }}/documentation/runtime/environments/">Runtime environments</a></li>
+ </ul>
+</li>
+
+<li class="section-nav-item--collapsible">
<span class="section-nav-list-title">Learning resources</span>
<ul class="section-nav-list">
diff --git a/website/src/_posts/2019-09-04-gsoc-19.md b/website/src/_posts/2019-09-04-gsoc-19.md
index a60e933..8fa16c6 100644
--- a/website/src/_posts/2019-09-04-gsoc-19.md
+++ b/website/src/_posts/2019-09-04-gsoc-19.md
@@ -49,7 +49,7 @@ I had already read the [Streaming Systems book](http://streamingsystems.net/). S
Before actually submitting a proposal, I went through a bunch of resources to make sure I had a concrete understanding of Beam.
I read the [Streaming 101](https://www.oreilly.com/ideas/the-world-beyond-batch-streaming-101) and [Streaming 102](https://www.oreilly.com/ideas/the-world-beyond-batch-streaming-102) blogs by Tyler Akidau. They are the perfect introduction to Beam’s unified model for Batch and Streaming.
In addition, I watched all Beam talks on YouTube. You can find them on the [Beam Website](https://beam.apache.org/documentation/resources/videos-and-podcasts/).
-Beam has really good documentation. The [Programming Guide](https://beam.apache.org/documentation/programming-guide/) lays out all of Beam’s concepts really well. [Beam’s execution model](https://beam.apache.org/documentation/execution-model/) is also documented well and is a must-read to understand how Beam processes data.
+Beam has really good documentation. The [Programming Guide](https://beam.apache.org/documentation/programming-guide/) lays out all of Beam’s concepts really well. [Beam’s execution model](https://beam.apache.org/documentation/runtime/model) is also documented well and is a must-read to understand how Beam processes data.
[waitingforcode.com](https://www.waitingforcode.com/apache-beam) also has good blog posts about Beam concepts.
To get a better sense of the Beam codebase, I played around with it and worked on some PRs to understand Beam better and got familiar with the test suite and workflows.
diff --git a/website/src/documentation/index.md b/website/src/documentation/index.md
index b9ac533..5000ea5 100644
--- a/website/src/documentation/index.md
+++ b/website/src/documentation/index.md
@@ -30,7 +30,7 @@ This section provides in-depth conceptual information and reference material for
Learn about the Beam Programming Model and the concepts common to all Beam SDKs and Runners.
* Read the [Programming Guide]({{ site.baseurl }}/documentation/programming-guide/), which introduces all the key Beam concepts.
-* Learn about Beam's [execution model]({{ site.baseurl }}/documentation/execution-model/) to better understand how pipelines execute.
+* Learn about Beam's [execution model]({{ site.baseurl }}/documentation/runtime/model) to better understand how pipelines execute.
* Visit [Learning Resources]({{ site.baseurl }}/documentation/resources/learning-resources) for some of our favorite articles and talks about Beam.
## Pipeline Fundamentals
diff --git a/website/src/documentation/resources/learning-resources.md b/website/src/documentation/resources/learning-resources.md
index 1cba690..bf917cf 100644
--- a/website/src/documentation/resources/learning-resources.md
+++ b/website/src/documentation/resources/learning-resources.md
@@ -47,7 +47,7 @@ If you have additional material that you would like to see here, please let us k
* **[Programming Guide](https://beam.apache.org/documentation/programming-guide/)** - The Programming Guide contains more in-depth information on most topics in the Apache Beam SDK. These include descriptions on how everything works as well as code snippets to see how to use every part. This can be used as a reference guidebook.
* **[The world beyond batch: Streaming 101](https://www.oreilly.com/ideas/the-world-beyond-batch-streaming-101)** - Covers some basic background information, terminology, time domains, batch processing, and streaming.
* **[The world beyond batch: Streaming 102](https://www.oreilly.com/ideas/the-world-beyond-batch-streaming-102)** - Tour of the unified batch and streaming programming model in Beam, alongside with an example to explain many of the concepts.
-* **[Apache Beam Execution Model](https://beam.apache.org/documentation/execution-model/)** - Explanation on how runners execute an Apache Beam pipeline. This includes why serialization is important, and how a runner might distribute the work in parallel to multiple machines.
+* **[Apache Beam Execution Model](https://beam.apache.org/documentation/runtime/model)** - Explanation on how runners execute an Apache Beam pipeline. This includes why serialization is important, and how a runner might distribute the work in parallel to multiple machines.
### Common Patterns
diff --git a/website/src/documentation/runtime/environments.md b/website/src/documentation/runtime/environments.md
new file mode 100644
index 0000000..22a96dd
--- /dev/null
+++ b/website/src/documentation/runtime/environments.md
@@ -0,0 +1,183 @@
+---
+layout: section
+title: "Runtime environments"
+section_menu: section-menu/documentation.html
+permalink: /documentation/runtime/environments/
+---
+<!--
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+# Runtime environments
+
+The Beam SDK runtime environment is isolated from other runtime systems because the SDK runtime environment is [containerized](https://s.apache.org/beam-fn-api-container-contract) with [Docker](https://www.docker.com/). This means that any execution engine can run the Beam SDK.
+
+This page describes how to customize, build, and push Beam SDK container images.
+
+Before you begin, install [Docker](https://www.docker.com/) on your workstation.
+
+## Customizing container images
+
+You can add extra dependencies to container images so that you don't have to supply the dependencies to execution engines.
+
+To customize a container image, either:
+* [Write a new](#writing-new-dockerfiles) [Dockerfile](https://docs.docker.com/engine/reference/builder/) on top of the original.
+* [Modify](#modifying-dockerfiles) the [original Dockerfile](https://github.com/apache/beam/blob/master/sdks/python/container/Dockerfile) and reimage the container.
+
+It's often easier to write a new Dockerfile. However, by modifying the original Dockerfile, you can customize anything (including the base OS).
+
+### Writing new Dockerfiles on top of the original {#writing-new-dockerfiles}
+
+1. Pull a [prebuilt SDK container image](https://hub.docker.com/u/apachebeam) for your [target](https://docs.docker.com/docker-hub/repos/#searching-for-repositories) language and version. The following example pulls the latest Python SDK:
+```
+docker pull apachebeam/python3.7_sdk
+```
+2. [Write a new Dockerfile](https://docs.docker.com/develop/develop-images/dockerfile_best-practices/) that [designates](https://docs.docker.com/engine/reference/builder/#from) the original as its [parent](https://docs.docker.com/glossary/?term=parent%20image).
+3. [Build](#building-container-images) a child image.
+
+### Modifying the original Dockerfile {#modifying-dockerfiles}
+
+1. Clone the `beam` repository:
+```
+git clone https://github.com/apache/beam.git
+```
+2. Customize the [Dockerfile](https://github.com/apache/beam/blob/master/sdks/python/container/Dockerfile). If you're adding dependencies from [PyPI](https://pypi.org/), use [`base_image_requirements.txt`](https://github.com/apache/beam/blob/master/sdks/python/container/base_image_requirements.txt) instead.
+3. [Reimage](#building-container-images) the container.
+
+### Testing customized images
+
+To test a customized image locally, run a pipeline with PortableRunner and set the `--environment_config` flag to the image path:
+
+{:.runner-direct}
+
+```
+python -m apache_beam.examples.wordcount \
+--input=/path/to/inputfile \
+--output /path/to/write/counts \
+--runner=PortableRunner \
+--job_endpoint=embed \
+--environment_config=path/to/container/image
+```
+
+{:.runner-flink-local}
+
+```
+# Start a Flink job server on localhost:8099
+./gradlew :runners:flink:1.5:job-server:runShadow
+
+# Run a pipeline on the Flink job server
+python -m apache_beam.examples.wordcount \
+--input=/path/to/inputfile \
+--output=/path/to/write/counts \
+--runner=PortableRunner \
+--job_endpoint=localhost:8099 \
+--environment_config=path/to/container/image
+```
+
+{:.runner-spark-local}
+
+```
+# Start a Spark job server on localhost:8099
+./gradlew :runners:spark:job-server:runShadow
+
+# Run a pipeline on the Spark job server
+python -m apache_beam.examples.wordcount \
+--input=/path/to/inputfile \
+--output=path/to/write/counts \
+--runner=PortableRunner \
+--job_endpoint=localhost:8099 \
+--environment_config=path/to/container/image
+```
+
+To test a customized image on the Google Cloud Dataflow runner, use the `DataflowRunner` option and the `worker_harness_container_image` flag:
+
+```
+python -m apache_beam.examples.wordcount \
+--input=path/to/inputfile \
+--output=/path/to/write/counts \
+--runner=DataflowRunner \
+--project={gcp_project_id} \
+--temp_location={gcs_location} \ \
+--experiment=beam_fn_api \
+--sdk_location=[…]/beam/sdks/python/container/py{version}/build/target/apache-beam.tar.gz \
+--worker_harness_container_image=path/to/container/image
+
+# The sdk_location option accepts four Python version variables: 2, 35, 36, and 37
+```
+
+## Building container images
+
+To build Beam SDK container images:
+
+1. Navigate to the local copy of your [customized container image](#customizing-container-images).
+2. Run Gradle with the `docker` target. If you're [building a child image](#writing-new-dockerfiles), set the optional `--file` flag to the new Dockerfile. If you're [building an image from an original Dockerfile](#modifying-dockerfiles), ignore the `--file` flag and use a default repository:
+
+```
+# The default repository of each SDK
+./gradlew [--file=path/to/new/Dockerfile] :sdks:java:container:docker
+./gradlew [--file=path/to/new/Dockerfile] :sdks:go:container:docker
+./gradlew [--file=path/to/new/Dockerfile] :sdks:python:container:py2:docker
+./gradlew [--file=path/to/new/Dockerfile] :sdks:python:container:py35:docker
+./gradlew [--file=path/to/new/Dockerfile] :sdks:python:container:py36:docker
+./gradlew [--file=path/to/new/Dockerfile] :sdks:python:container:py37:docker
+
+# Shortcut for building all four Python SDKs
+./gradlew [--file=path/to/new/Dockerfile] :sdks:python:container buildAll
+```
+
+To examine the containers that you built, run `docker images` from anywhere in the command line. If you successfully built all of the container images, the command prints a table like the following:
+```
+REPOSITORY TAG IMAGE ID CREATED SIZE
+apachebeam/java_sdk latest 16ca619d489e 2 weeks ago 550MB
+apachebeam/python2.7_sdk latest b6fb40539c29 2 weeks ago 1.78GB
+apachebeam/python3.5_sdk latest bae309000d09 2 weeks ago 1.85GB
+apachebeam/python3.6_sdk latest 42faad307d1a 2 weeks ago 1.86GB
+apachebeam/python3.7_sdk latest 18267df54139 2 weeks ago 1.86GB
+apachebeam/go_sdk latest 30cf602e9763 2 weeks ago 124MB
+```
+
+### Overriding default Docker targets
+
+The default [tag](https://docs.docker.com/engine/reference/commandline/tag/) is `latest` and the default repositories are in the Docker Hub `apachebeam` namespace. The `docker` command-line tool implicitly [pushes container images](#pushing-container-images) to this location.
+
+To tag a local image, set the `docker-tag` option when building the container. The following command tags a Python SDK image with a date.
+```
+./gradlew :sdks:python:container:py2:docker -Pdocker-tag=2019-10-04
+```
+
+To change the repository, set the `docker-repository-root` option to a new location. The following command sets the `docker-repository-root` to a Bintray repository named `apache`.
+```
+./gradlew :sdks:python:container:py2:docker -Pdocker-repository-root=$USER-docker-apache.bintray.io/beam/python
+```
+
+## Pushing container images
+
+After [building a container image](#building-container-images), you can store it in a remote Docker repository.
+
+The following steps push a Python SDK image to the [`docker-root-repository` value](#overriding-default-docker-targets).
+
+1. Sign in to your Docker registry:
+```
+docker login
+```
+2. Navigate to the local copy of your container image and upload it to the remote repository:
+```
+docker push apachebeam/python2.7_sdk
+```
+
+To download the image again, run `docker pull`:
+```
+docker pull apachebeam/python2.7_sdk
+```
+
+> **Note**: After pushing a container image, the remote image ID and digest match the local image ID and digest.
\ No newline at end of file
diff --git a/website/src/documentation/execution-model.md b/website/src/documentation/runtime/model.md
similarity index 98%
rename from website/src/documentation/execution-model.md
rename to website/src/documentation/runtime/model.md
index 70ab703..4affaca 100644
--- a/website/src/documentation/execution-model.md
+++ b/website/src/documentation/runtime/model.md
@@ -1,8 +1,10 @@
---
layout: section
-title: "Beam Execution Model"
+title: "Execution model"
section_menu: section-menu/documentation.html
-permalink: /documentation/execution-model/
+permalink: /documentation/runtime/model/
+redirect_from:
+ - /documentation/execution-model/
---
<!--
Licensed under the Apache License, Version 2.0 (the "License");
@@ -18,7 +20,7 @@ See the License for the specific language governing permissions and
limitations under the License.
-->
-# Apache Beam Execution Model
+# Execution model
The Beam model allows runners to execute your pipeline in different ways. You
may observe various effects as a result of the runner’s choices. This page
@@ -207,4 +209,4 @@ All `DoFns` that experience coupled failures are terminated and must be torn
down since they aren’t following the normal `DoFn` lifecycle .
Executing transforms this way allows a runner to avoid persisting elements
-between transforms, saving on persistence costs.
+between transforms, saving on persistence costs.
\ No newline at end of file
diff --git a/website/src/documentation/transforms/python/element-wise/pardo.md b/website/src/documentation/transforms/python/element-wise/pardo.md
index b481dab..20c8885 100644
--- a/website/src/documentation/transforms/python/element-wise/pardo.md
+++ b/website/src/documentation/transforms/python/element-wise/pardo.md
@@ -115,7 +115,7 @@ A [`DoFn`](https://beam.apache.org/releases/pydoc/current/apache_beam.transforms
can be customized with a number of methods that can help create more complex behaviors.
You can customize what a worker does when it starts and shuts down with `setup` and `teardown`.
You can also customize what to do when a
-[*bundle of elements*](https://beam.apache.org/documentation/execution-model/#bundling-and-persistence)
+[*bundle of elements*](https://beam.apache.org/documentation/runtime/model/#bundling-and-persistence)
starts and finishes with `start_bundle` and `finish_bundle`.
* [`DoFn.setup()`](https://beam.apache.org/releases/pydoc/current/apache_beam.transforms.core.html#apache_beam.transforms.core.DoFn.setup):