feat(avro-schema): logical type support

[joscha]

This implements logical type support for:

• timestamp
• date

for the OpenAPI built-in string formats:

• date-time
• date

The change is backwards compatible by allowing to opt-in to the behaviour via a new property useLogicalTypes.
Avro's support for timestamp fields includes the definition which timescale they are represented in (milliseconds, microseconds or nanoseconds). This can be controlled via a new property logicalTypeTimeQuantifier.

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[joscha]

would be great to format this better; if there is a way to use whitespace in the template and then make it collapse in the result, please let me know.

[wing328]

are you looking for something like following?

https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/resources/Javascript/libraries/javascript/api.mustache#L3
https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/resources/Javascript/libraries/javascript/api.mustache#L118

[joscha]

no, that's changing the template operator, right? I basically wish I could change the string in this template to:

Suggested change

	{{#useLogicalTypes}}{{#isDate}}{ "type": "int", "logicalType": "date" }{{/isDate}}{{#isDateTime}}{ "type": "long", "logicalType": "timestamp-{{{logicalTypeTimeQuantifier}}}" }{{/isDateTime}}{{^isDate}}{{^isDateTime}}"{{{dataType}}}"{{/isDateTime}}{{/isDate}}{{/useLogicalTypes}}{{^useLogicalTypes}}"{{{dataType}}}"{{/useLogicalTypes}}
	{{#useLogicalTypes}}
	{{#isDate}}
	{
	"type": "int",
	"logicalType": "date"
	}
	{{/isDate}}
	{{#isDateTime}}
	{
	"type": "long",
	"logicalType": "timestamp-{{{logicalTypeTimeQuantifier}}}"
	}
	{{/isDateTime}}
	{{^isDate}}
	{{^isDateTime}}
	"{{{dataType}}}"
	{{/isDateTime}}
	{{/isDate}}
	{{/useLogicalTypes}}
	{{^useLogicalTypes}}
	"{{{dataType}}}"
	{{/useLogicalTypes}}

and still have well-spaced output in the resulting schema. Something like a {{#collapseWhitespace}}...{{/collapseWhitespace}} operator that takes anything in its body and reduces all \w+ to

[wing328]

nope. i don't think mustache comes with anything to do that

looks like avsc file are just JSON file so users can use a linter to auto format the auto-generated output as they do with other generators