Description of cfn-lint development environment and build steps

[matsev]

cfn-lint version:
cfn-lint 0.20.1

Description of issue.

In the Contributing via Pull Requests paragraph, it is stated that

3. Ensure local tests pass.

However, neither in the CONTRIBUTING.md nor in the README.md document is it described how one can setup the cfn-lint development environment and execute these tests.

[fatbasstard]

Yeah, you're completely right, the development setup is not really described.
We'll make sure this is (better) documented.

Do you need any help or got a specific question right now @matsev ?

[matsev]

@fatbasstard My intention was to setup the build environment and play with it to get a better understanding of the linter and CloudFormation, however I got stuck before I started. I have only some Python experience and last time I tried I spent a lot of time struggling with installing runtime versions, dependency management (pip, anaconda, virtualenv) and so on before I could do anything useful. I suggest that you add a few lines about required runtime, tools (if any, preferably with a link to each homepage respectively), environment config etc to your documentation.

[PatMyron]

Biggest thing that helped me was realizing local repositories can be installed using:
pip3 install -e .

These commands check which Python and cfn-lint version you're currently using:

which cfn-lint | xargs cat
pip3 show cfn-lint

(the officially released version can be forcibly reinstalled)

[PatMyron]

common PRs

new region
new availability zones
new lambda runtimes parsed from botocore
new instance types parsed from pricing
new aws-sam-translator
new Python version
~weekly maintenance script / release
Visual Studio Code extension ~weekly maintenance script / release

rough estimate of maintenance per rule

CLI parameters added to cfnlint.core.run_cli(), data/CfnLintCli/config/schema.json, + another argparse.ArgumentParser.add_argument()

script to generate test snapshots

commonly maintained structured property information

AdditionalSpecs/RdsProperties.json written by scripts/update_specs_from_pricing.py
AdditionalSpecs/Policies.json written by cfn-lint --update-iam-policies

At least one of these properties must be specified:

cfn-lint/src/cfnlint/data/AdditionalSpecs/AtLeastOne.json

Lines 20 to 25 in b788cc9

	"AWS::EC2::Instance": [
	[
	"ImageId",
	"LaunchTemplate"
	]
	],

Only one of these properties may be specified:

cfn-lint/src/cfnlint/data/AdditionalSpecs/OnlyOne.json

Lines 79 to 84 in b788cc9

	"AWS::CloudWatch::Alarm": [
	[
	"MetricName",
	"Metrics"
	]
	],

If this property (SnapshotIdentifier) is specified, these properties must be excluded:

cfn-lint/src/cfnlint/data/AdditionalSpecs/Exclusive.json

Lines 102 to 107 in b788cc9

	"AWS::RDS::DBCluster": {
	"SnapshotIdentifier": [
	"MasterUsername",
	"MasterUserPassword"
	]
	},

If this property (VpcId) is specified, these properties must be included:

cfn-lint/src/cfnlint/data/AdditionalSpecs/Inclusive.json

Lines 48 to 52 in b788cc9

	"AWS::OpsWorks::Stack": {
	"VpcId": [
	"DefaultSubnetId"
	]
	}

---

ExtendedSpecs/$REGION/05_pricing_property_values.json written by scripts/update_specs_from_pricing.py
ExtendedSpecs/$REGION/06_ssm_service_removal.json written by scripts/update_specs_services_from_ssm.py
ExtendedSpecs/$REGION/07_ssm_service_addition.json written by scripts/update_specs_services_from_ssm.py

Allowed values from botocore (preferred):

cfn-lint/src/cfnlint/data/ExtendedSpecs/all/03_value_types/aws_glue.json

Lines 2 to 8 in 1f39305

	{
	"op": "add",
	"path": "/ValueTypes/AWS::Glue::Connection.ConnectionInput.ConnectionType",
	"value": {
	"botocore": "glue/2017-03-31/ConnectionType"
	}
	},

Allowed values (hardcoded):

cfn-lint/src/cfnlint/data/ExtendedSpecs/all/03_value_types/aws_codebuild.json

Lines 2 to 11 in 6cce922

	{
	"op": "add",
	"path": "/ValueTypes/AWS::CodeBuild::Project.Artifacts.Packaging",
	"value": {
	"AllowedValues": [
	"NONE",
	"ZIP"
	]
	}
	},

Allowed patterns:

cfn-lint/src/cfnlint/data/ExtendedSpecs/all/03_value_types.json

Lines 33 to 36 in a46773c

	"CidrIp": {
	"AllowedPattern": "x.x.x.x/y",
	"AllowedPatternRegex": "^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])(/([0-9]|[1-2][0-9]|3[0-2]))$"
	},

Number size constraints:

cfn-lint/src/cfnlint/data/ExtendedSpecs/all/03_value_types/aws_sqs.json

Lines 17 to 24 in df8d065

	{
	"op": "add",
	"path": "/ValueTypes/AWS::SQS::Queue.MaximumMessageSize",
	"value": {
	"NumberMax": 262144,
	"NumberMin": 1024
	}
	},

String size constraints:

cfn-lint/src/cfnlint/data/ExtendedSpecs/all/03_value_types/aws_logs.json

Lines 2 to 9 in 67fc5bb

	{
	"op": "add",
	"path": "/ValueTypes/AWS::Logs::LogGroup.LogGroupName",
	"value": {
	"StringMax": 512,
	"StringMin": 1
	}
	},

List size constraints:

cfn-lint/src/cfnlint/data/ExtendedSpecs/all/03_value_types/aws_iam.json

Lines 71 to 78 in 6cce922

	{
	"op": "add",
	"path": "/ValueTypes/AWS::IAM::Group.Names",
	"value": {
	"ListMax": 10,
	"ListMin": 0
	}
	},

Json size constraints

---

There should be no functional difference, but 03_value_types and 04_property_values are more organized than 03_value_types.json and 04_property_values.json, so they should be preferred locations for new constraints

---

After editing src/cfnlint/data/ExtendedSpecs, the necessary CloudSpecs changes should be auto-generatable by running:

cfn-python-lint $ pip3 install -e .
cfn-python-lint $ cfn-lint --update-specs # https://github.com/aws-cloudformation/cfn-python-lint/pull/1383#issuecomment-629891506

[miparnisari]

In the Contributing via Pull Requests paragraph, it is stated that "Ensure local tests pass."
However, neither in the CONTRIBUTING.md nor in the README.md document is it described how one can setup the cfn-lint development environment and execute these tests.

This is now documented here: https://github.com/aws-cloudformation/cfn-python-lint/blob/master/CONTRIBUTING.md#development-environment

Resolving :)