High Cyclomatic complexity score

[abraverm]

Running radon on Linchpin code show bad complexity scores:

➜ radon cc linchpin/ -nc -s
linchpin/__init__.py
    M 460:4 LinchpinAPI.do_action - E (38)
    M 805:4 LinchpinAPI.get_run_data - C (18)
    M 392:4 LinchpinAPI.get_pf_data_from_rundb - C (17)
    M 239:4 LinchpinAPI.lp_journal - C (14)
    M 936:4 LinchpinAPI._invoke_playbooks - C (13)
linchpin/InventoryFilters/JSONInventoryFormatter.py
    M 48:4 JSONInventoryFormatter.add_ips_to_groups - C (11)
linchpin/cli/__init__.py
    M 247:4 LinchpinCli._write_distilled_context - D (24)
    M 128:4 LinchpinCli._write_to_inventory - C (16)
    M 526:4 LinchpinCli._execute_action - C (14)
linchpin/shell/__init__.py
    F 436:0 journal - D (29)
    F 26:0 _handle_results - C (13)
    F 229:0 up - C (12)
    F 321:0 destroy - C (11)
linchpin/provision/library/async_status_custom.py
    F 58:0 main - C (11)
linchpin/provision/library/bkr_server.py
    M 47:4 BkrFactory.provision - D (29)
linchpin/provision/library/rundb.py
    F 85:0 main - D (23)
linchpin/provision/roles/ovirt/files/inventory.py
    M 53:4 Inventory.config_value_helper - C (13)
linchpin/provision/roles/openstack/files/inventory.py
    C 8:0 Inventory - C (13)
    M 11:4 Inventory.get_host_data - C (13)
linchpin/validator/__init__.py
    M 64:4 Validator.validate_pretty - C (17)
    M 321:4 Validator._convert_topology - C (13)
linchpin/validator/anyofvalidator.py
    M 10:4 AnyofValidator._validate_anyof - C (11)
linchpin/fetch/fetch.py
    M 62:4 Fetch.copy_dir - C (18)

Complexity Number	Meaning
1-10	Structured and well written code, High Testability Cost and Effort is less
10-20	Complex Code Medium, Testability Cost and effort is Medium
20-40	Very complex Code Low, Testability Cost and Effort are high
over 40	Not at all testable, Very high Cost and Effort

reference:
https://www.guru99.com/cyclomatic-complexity.html
https://en.wikipedia.org/wiki/Cyclomatic_complexity
https://github.com/rubik/radon/

Breaking down by levels:

E

linchpin/init.py
M 460:4 LinchpinAPI.do_action - E

D

linchpin/cli/init.py
M 247:4 LinchpinCli._write_distilled_context - D
linchpin/shell/init.py
F 436:0 journal - D
linchpin/provision/library/bkr_server.py
M 47:4 BkrFactory.provision - D
linchpin/provision/library/rundb.py
F 85:0 main - D

C

linchpin/init.py
M 805:4 LinchpinAPI.get_run_data - C
M 392:4 LinchpinAPI.get_pf_data_from_rundb - C
M 239:4 LinchpinAPI.lp_journal - C
M 936:4 LinchpinAPI._invoke_playbooks - C
linchpin/InventoryFilters/JSONInventoryFormatter.py
M 48:4 JSONInventoryFormatter.add_ips_to_groups - C
linchpin/cli/init.py
M 128:4 LinchpinCli._write_to_inventory - C
M 526:4 LinchpinCli._execute_action - C
linchpin/shell/init.py
F 26:0 _handle_results - C
F 229:0 up - C
F 321:0 destroy - C
linchpin/provision/library/async_status_custom.py
F 58:0 main - C
linchpin/provision/roles/ovirt/files/inventory.py
M 53:4 Inventory.config_value_helper - C
linchpin/provision/roles/openstack/files/inventory.py
C 8:0 Inventory - C
M 11:4 Inventory.get_host_data - C
linchpin/validator/init.py
M 64:4 Validator.validate_pretty - C
M 321:4 Validator._convert_topology - C
linchpin/validator/anyofvalidator.py
M 10:4 AnyofValidator._validate_anyof - C
linchpin/fetch/fetch.py
M 62:4 Fetch.copy_dir - C

[14rcole]

Fixing this will probably require a few PRs. The first priority is probably to break up do_action() into multiple functions

Also, as you reduce the complexity, can you put together a guide of how to write "good" functions/code? I know some projects are pretty strict about limiting the amount of indentation or lines in a function but I don't know too much about best practices

[Dannyb48]

Cool tool! Curious if you include a -a to the above command, whats' the overall score? Carbon ended up with a C.

[abraverm]

23 blocks (classes, functions, methods) analyzed.
Average complexity: C (17.0)

@14rcole, I can look for reference but what I like about this tool is that it will give absolute feedback (not an opinion).

[samvarankashyap]

@14rcole Add issues on reducing complexity.