Docker improvements

[jonasbn]

• Added docker ignore file as suggested in Push image to Docker Hub or GitHub Packages #9
• Also migrated to Docker image python-3.8 slim, which is quite slim.

Experimented with Alpine without success, some of the XML requirements did not work.

[jonasbn]

I have added a branch with my Alpine work, ref:

• https://github.com/rojopolis/spellcheck-github-actions/tree/docker_alpine

[edumco]

I've try the docker image in a few repositories and here here my test notes:

1. Readme could to be updated to point to the docker hub image

2. Still needed to create a spellcheck.yml file with little information about its contents. A separate tutorial explaining in details should be created.

3. The example on reamdme has the worlist.txt listed so when we run without creating the file an error appears.

Could be a informative message like:

You have declared a $WORDLIST_FILE_NAME file in your spellcheck but it was not found!

Remove the file declaration from spellcheck or create the file with the same name.

4. The error message doesn't count correctly the numbers of files with errors

Misspelled words:
<htmlcontent> resources/frameworks/cucumber.md: html>body>ul>li>p
--------------------------------------------------------------------------------
UI
--------------------------------------------------------------------------------

Misspelled words:
<htmlcontent> resources/frameworks/jasmine.md: html>body>ul>li
--------------------------------------------------------------------------------
Aprenda
Javascript
Unitários
--------------------------------------------------------------------------------

!!!Spelling check failed!!!
(1) Files in repository contain spelling errors

5. The html tags in the log might be confusing. It's not easy to transpile markdown into html using the brain :P

Later I post comments about the Dockerfile

[edumco]

My notes on the debian image

1. Debian-slim is great!

2. --no-install-recommends

In debian based images its a good practice to add --no-install-recommends to avoid download extra-packages. If some of these packages are really necessary they should be explicitly as a depend

RUN apt-get update \
    && apt-get install -y --no-install-recommends aspell aspell-en \
    && rm -rf /var/lib/apt/lists/*

3. Pin pip versions using pip freeze

Its a good practice to pin the exact version used for each package and its dependences and put on a requirements.txt.

This forces the docker image build to aways produce the same result.

Today on python:3.8-slim the command pip install pyspelling && pip freeze creates the following list:

backrefs==4.3
beautifulsoup4==4.9.1
bracex==2.0
html5lib==1.0.1
lxml==4.5.1
Markdown==3.2.2
pyspelling==2.6
PyYAML==5.3.1
six==1.15.0
soupsieve==2.0.1
wcmatch==6.0.1
webencodings==0.5.1

[edumco]

About Docker alpine

1) You can have multiple Dockerfiles

Dockerfile
Dockerfile.python37
Dockerfile.python37-alpine11
Dockerfile.python38-alpine11

2) In alpine we don't need to update

Just use the --no-cache and the apk will be found download and installed without touching the cache.

Ex: apk add --no-cache package

3) Temporary package installation

Sometimes we just gonna use a package during build or installation (gcc) so there are 2 approachs:

• Create a multistage build: Great but more complex

• Install, use and uninstall on the same RUN: good for a single package

Ex: RUN apt install unzip && unzip myfile.zip && apt uninstall unzip

4) Building wheel for lxml takes a huge amount of time.

This doeesn't feel right. i believe it could be some bad config in lxml setup.py.

5) Alpine is so good at making small images. Dont give up!

github-action-spellcheck:alpine 106MB
github-action-spellcheck:latest 211MB

[jonasbn]

Hi @edumco

Thanks for the elaborate feedback. I have compiled your comments to this list:

• Mention Docker image in README
• Investigate observed spellcheck.yml issue
• Add possible tutorial for getting started
• Make boilerplate example without wordlist.txt
• Investigate observed wordlist.txt issue
• Evaluate wordlist detection enhancement, moved to Evaluate wordlist detection enhancement #16
• Investigate possible issue with error count PySpelling, moved to Investigate possible issue with error count PySpelling #15
• Investigate possibility to suppress HTML output from PySpelling, moved to Investigate possibility of suppressing HTML tags in output #14
• Simplify Debian build using: --no-install-recommends
• Investigate need for aspell-en Debian package
• Extend Docker build with Python requirements from pip freeze
• Evaluate option for using Alpine based Python image, moved to Investigate migration to Alpine over Debian #13

[jonasbn]

Improvements and issues, which will be addressed separately have been migrated to separate issues. Documentation has been updated and things have been slimmed down.

Many areas could do with further improvements:

• Documentation
• Tutorials
• And of course additional features