Port to psycopg3

[j-bennet]

Description

Port pgcli to psycopg3. Work in progress.

Checklist

• I've added this contribution to the changelog.rst.
• I've added my name to the AUTHORS file (or it's already there).

• I installed pre-commit hooks (pip install pre-commit && pre-commit install), and ran black on my code.
• Please squash merge this pull request (uncheck if you'd like us to merge as multiple commits)

[j-bennet]

@dvarrazzo Can you advise about register_json_typecasters here?

pgcli/pgcli/pgexecute.py

Line 105 in 366c01b

def register_json_typecasters(conn, loads_fn):

Do we still need this, and what would be the equivalent in psycopg if yes?

[dvarrazzo]

@dvarrazzo Can you advise about register_json_typecasters here?

@j-bennet I seem to remember that you only use that function to actually disable json loading, by calling register_json_typecasters(conn, lambda x: x), so that people would see the json data instead of the repr of the python objects. If that's the case, I suggest you to register the text loader for it as you do in register_typecasters() with other types:

def register_typecasters(connection):
    ...
    connection.adapters.register_loader("json", psycopg.types.string.TextLoader)
    connection.adapters.register_loader("jsonb", psycopg.types.string.TextLoader)

and to drop register_json_typecaster() altogether.

A function similar to the psycopg2 one is available as psycopg.types.json.set_json_loads (see Json adaptation for details), but I don't think it covers your use case. That function is meant to customise loads(); you need to disable it.

The exception checking in the old code is not necessary. It was necessary in the past to look for the oid of json/jsonb types, when they were still Postgres extensions. Now that they are in core, their oids are fixed and well known, so psycopg doesn't need to run queries which might fail. Even if you run pgcli with an old Postgres version, the function calls in register_typecaster() wouldn't fail.

[lgtm-com]

This pull request introduces 2 alerts and fixes 3 when merging 36b890a into 372da81 - view on LGTM.com

new alerts:

• 2 for Unused import

fixed alerts:

• 2 for Module is imported with 'import' and 'import from'
• 1 for Module is imported more than once

[lgtm-com]

This pull request introduces 2 alerts and fixes 3 when merging 3217134 into 372da81 - view on LGTM.com

new alerts:

• 2 for Unused import

fixed alerts:

• 2 for Module is imported with 'import' and 'import from'
• 1 for Module is imported more than once

[codecov-commenter]

Codecov Report

Merging #1324 (b581b75) into main (6884c29) will decrease coverage by 5.02%.
The diff coverage is 34.42%.

@@            Coverage Diff             @@
##             main    #1324      +/-   ##
==========================================
- Coverage   84.15%   79.13%   -5.03%     
==========================================
  Files          21       23       +2     
  Lines        2720     2880     +160     
==========================================
- Hits         2289     2279      -10     
- Misses        431      601     +170     

Impacted Files	Coverage Δ
pgcli/pgtoolbar.py	31.57% <0.00%> (+0.15%)	⬆️
pgcli/pyev.py	15.38% <15.38%> (ø)
pgcli/explain_output_formatter.py	46.15% <46.15%> (ø)
pgcli/key_bindings.py	52.94% <50.00%> (-0.19%)	⬇️
pgcli/pgexecute.py	82.52% <83.92%> (+2.15%)	⬆️
pgcli/main.py	78.15% <89.47%> (-0.39%)	⬇️
pgcli/__init__.py	100.00% <100.00%> (ø)
pgcli/packages/prioritization.py	96.96% <0.00%> (-3.04%)	⬇️
... and 3 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 372da81...b581b75. Read the comment docs.

[lgtm-com]

This pull request introduces 2 alerts and fixes 3 when merging 51459a5 into 372da81 - view on LGTM.com

new alerts:

• 2 for Unused import

fixed alerts:

• 2 for Module is imported with 'import' and 'import from'
• 1 for Module is imported more than once

[lgtm-com]

This pull request introduces 2 alerts and fixes 3 when merging a6188c4 into 372da81 - view on LGTM.com

new alerts:

• 2 for Unused import

fixed alerts:

• 2 for Module is imported with 'import' and 'import from'
• 1 for Module is imported more than once

[lgtm-com]

This pull request introduces 2 alerts and fixes 3 when merging e2584f3 into 372da81 - view on LGTM.com

new alerts:

• 2 for Unused import

fixed alerts:

• 2 for Module is imported with 'import' and 'import from'
• 1 for Module is imported more than once

[lgtm-com]

This pull request fixes 3 alerts when merging edd3b49 into 372da81 - view on LGTM.com

fixed alerts:

• 2 for Module is imported with 'import' and 'import from'
• 1 for Module is imported more than once

[lgtm-com]

This pull request fixes 3 alerts when merging b581b75 into 372da81 - view on LGTM.com

fixed alerts:

• 2 for Module is imported with 'import' and 'import from'
• 1 for Module is imported more than once

[lgtm-com]

This pull request fixes 3 alerts when merging 840c6aa into 372da81 - view on LGTM.com

fixed alerts:

• 2 for Module is imported with 'import' and 'import from'
• 1 for Module is imported more than once

[lgtm-com]

This pull request fixes 3 alerts when merging 2c82435 into 372da81 - view on LGTM.com

fixed alerts:

• 2 for Module is imported with 'import' and 'import from'
• 1 for Module is imported more than once