Consider ComposedSchema in DefaultCodegen#fromRequestBody(..)

[jmini]

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Description of the PR

This is a fix for #192.

In DefaultCodegen#fromRequestBody(..) the composed-schema case was going through the default else case.

openapi-generator/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java

Lines 4247 to 4271 in 231202d

	} else {
	CodegenProperty codegenProperty = fromProperty("property", schema);
	if (schema.getAdditionalProperties() != null) {// http body is map
	LOGGER.error("Map should be supported. Please report to openapi-generator github repo about the issue.");
	} else if (codegenProperty != null) {
	LOGGER.warn("The following schema has undefined (null) baseType. " +
	"It could be due to form parameter defined in OpenAPI v2 spec with incorrect consumes. " +
	"A correct 'consumes' for form parameters should be " +
	"'application/x-www-form-urlencoded' or 'multipart/form-data'");
	LOGGER.warn("schema: " + schema);
	LOGGER.warn("Defaulting baseType to UNKNOWN_BASE_TYPE");
	codegenProperty.baseType = "UNKNOWN_BASE_TYPE";
	codegenParameter.baseName = codegenProperty.baseType;
	codegenParameter.baseType = codegenProperty.baseType;
	codegenParameter.dataType = codegenProperty.dataType;
	codegenParameter.description = codegenProperty.description;
	codegenParameter.paramName = toParamName(codegenProperty.baseType);
	if (codegenProperty.complexType != null) {
	imports.add(codegenProperty.complexType);
	}
	}
	setParameterBooleanFlagWithCodegenProperty(codegenParameter, codegenProperty);
	}

In my opinion, the composed-schema is more like the object case. This is why I have added || ModelUtils.isComposedSchema(schema) to the else condition here:

openapi-generator/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java

Lines 4229 to 4247 in 231202d

	} else if (ModelUtils.isObjectSchema(schema)) {
	CodegenModel codegenModel = null;
	if (StringUtils.isNotBlank(name)) {
	schema.setName(name);
	codegenModel = fromModel(name, schema, schemas);
	}
	if (codegenModel != null && !codegenModel.emptyVars) {
	if (StringUtils.isEmpty(bodyParameterName)) {
	codegenParameter.baseName = codegenModel.classname;
	} else {
	codegenParameter.baseName = bodyParameterName;
	}
	codegenParameter.paramName = toParamName(codegenParameter.baseName);
	codegenParameter.baseType = codegenModel.classname;
	codegenParameter.dataType = getTypeDeclaration(codegenModel.classname);
	codegenParameter.description = codegenModel.description;
	imports.add(codegenParameter.baseType);
	} else {

A unit test with the spec provided in #192 is added to the change to demonstrate the effect of the change.

[jmini]

Technical Committee for DefaultCodegen is the core Team Members:
@wing328 (2015/07)
@jimschubert (2016/05)
@cbornet (2016/05)
@jaz-ah (2016/05)
@ackintosh (2018/02)
@JFCote (2018/03)
@jmini (2018/04)

[JFCote]

Looks good to me. I will test it with my big spec and let you know.

[JFCote]

@jmini Like I said in the issue itself, the changes work in my spec. So If you want, I can merge this right now.
@wing328 Is this ok with you?

[jmini]

I am also in favor of this change (of course I proposed it), and I think 2 core team members are enough to validate the change.

[wing328]

I'm very busy these days and didn't have a chance to test it yet. I trust the change made by @jmini is of top quality and the review from you guys are sufficient. I'll take a look later and let you guys know if I've any questions.