chore(docs): Improve local installation guide

[hongquan]

Fixes #

Short description of what this resolves:

This PR is to improve installation guide for development.

After this PR, another improvement in settings system should be added to make our software adapt better with different Postgres connection methods for various circumstance. For example:

• For local development: Favor "ident" method (just need same username, no need password).
• For prod where PostgreSQL stays in the same machine as backend: Favor "ident" method.
• For container-based deployment: Follow database URL (because PostgreSQL run in other container), where password may not even needed, if we configure Postgres container to "trust" web app container.

Changes proposed in this pull request:

• Short command to install dependency softwares.
• Favor virtualenvwrapper for creating virtual environment (explanation is included).
• Favor "ident" connection method for PostgreSQL in development.

Checklist

• I have read the Contribution & Best practices Guide and my PR follows them.
• My branch is up-to-date with the Upstream development branch.
• The unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

• All the functions created/modified in this PR contain relevant docstrings.

[codecov]

Codecov Report

Merging #7320 into development will increase coverage by 0.05%.
The diff coverage is n/a.

@@               Coverage Diff               @@
##           development    #7320      +/-   ##
===============================================
+ Coverage        64.12%   64.18%   +0.05%     
===============================================
  Files              259      259              
  Lines            13086    13126      +40     
===============================================
+ Hits              8392     8425      +33     
- Misses            4694     4701       +7     

Impacted Files	Coverage Δ
app/api/admin_sales/utils.py	27.77% <0.00%> (-12.23%)	⬇️
app/api/helpers/query.py	54.54% <0.00%> (-1.98%)	⬇️
app/api/helpers/scheduled_jobs.py	59.18% <0.00%> (-0.82%)	⬇️
app/api/helpers/files.py	72.22% <0.00%> (-0.28%)	⬇️
app/api/helpers/notification.py	78.31% <0.00%> (-0.26%)	⬇️
app/api/events.py	37.31% <0.00%> (-0.19%)	⬇️
manage.py	0.00% <0.00%> (ø)
app/api/tax.py	52.45% <0.00%> (ø)
app/api/auth.py	23.82% <0.00%> (ø)
app/instance.py	87.77% <0.00%> (ø)
... and 56 more

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[iamareebjamal]

I think we should keep the dependencies explicitly listed here to avoid indirection and it's easier to track updates as well

[hongquan]

But this deb-packages.txt will help deploy process, it allows deploy script to automatically install new dependency if it is added.

[hongquan]

I've just added a note to README, to let developer know that the list of dependencies are in that file.

[iamareebjamal]

Since we use docker alpine to build the image, it doesn't help us in deployment particularly. Where else is it being used to install the dependencies?

[hongquan]

@iamareebjamal If you write down:

sudo apt install libpq-dev
brew install python@3

as before this PR, does it help you build Alpine Docker container?

The old README doesn't help you build Alpine Docker container, why do you use Alpine as excuse to refuse this change?

[iamareebjamal]

But this deb-packages.txt will help deploy process, it allows deploy script to automatically install new dependency if it is added.

I was commenting about this. Since we use alpine builds, debian dependencies don't help us in deployment process. Never said that the current docs help us in deployment process. Since, a separate file does not help us in the deployment process, why do we need to add an extra file and an indirection. Any change should have a net positive impact in the maintenance and developer experience.

[hongquan]

@iamareebjamal

debian dependencies don't help us in deployment process

This PR doesn't interfere the deployment process. It is addressing the "local installation guide". Before this PR, the documentation is guiding beginner to setup development environment on Ubuntu/Debian, and this PR still focus on it.
If you want to improve deployment process, let's do it in separate PR.

[hongquan]

add an extra file and an indirection

That extra file is to help developer install dependencies in one command, and also, if the dependencies list grows over time, it just make that file grow instead of this document. If you concern about list of packages staying in separate file, why don't you concern the requirements.txt, which is also a separate file to list dependencies?

[iamareebjamal]

The repo is not cloned at this point. People will copy paste the command and be greeted with an error

[hongquan]

Then I move this command down to after "cloning".

[hongquan]

This part is already after "cloning".

[iamareebjamal]

Other that the pull rebase command, other changes LGTM