openapi-generator fix: null exception error with addImport(composed, refSchema, m, modelName).

Closes https://github.com/OpenAPITools/openapi-generator/issues/13588

Hi team.

The following error occurred while generating a k6 scenario from oas using openapi-generator-cli version 6.2.0.

Exception in thread "main" java.lang.RuntimeException: Could not process model 'CommonSiteLink'.Please make sure that your schema is correct!
        at org.openapitools.codegen.DefaultGenerator.generateModels(DefaultGenerator.java:518)
        at org.openapitools.codegen.DefaultGenerator.generate(DefaultGenerator.java:912)
        at org.openapitools.codegen.cmd.Generate.execute(Generate.java:465)
        at org.openapitools.codegen.cmd.OpenApiGeneratorCommand.run(OpenApiGeneratorCommand.java:32)
        at org.openapitools.codegen.OpenAPIGenerator.main(OpenAPIGenerator.java:66)
Caused by: java.lang.NullPointerException: Cannot invoke "io.swagger.v3.oas.models.media.Schema.getDiscriminator()" because "childSchema" is null
        at org.openapitools.codegen.DefaultCodegen.addImport(DefaultCodegen.java:5497)
        at org.openapitools.codegen.DefaultCodegen.updateModelForComposedSchema(DefaultCodegen.java:2633)
        at org.openapitools.codegen.DefaultCodegen.fromModel(DefaultCodegen.java:2963)
        at org.openapitools.codegen.DefaultGenerator.processModels(DefaultGenerator.java:1291)
        at org.openapitools.codegen.DefaultGenerator.generateModels(DefaultGenerator.java:513)
        ... 4 more

This error is occurred if allDefinitions is null or allDefinitions.get(ref) returned null.

Therefore i added null check of the childSchema to the if statement.

This error was generated by https://github.com/OpenAPITools/openapi-generator/pull/12798.

The release that incorporates this PR appears to be 6.1.0, so versions above 6.1.0 may have the above error.

Signed-off-by: mugioka [email protected]

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./bin/utils/export_docs_generators.sh
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Oct 04 '22 09:10 mugioka

thanks for the fix. let me review later today.

Oct 05 '22 13:10 wing328

@mugioka can you please share a spec to reproduce the issue?

Oct 06 '22 16:10 wing328

@wing328 sorry for delay. I will share the specs to reproduce this issue later today.

Oct 11 '22 05:10 mugioka

Although still being verified, this PR may not be necessary since the root cause is incorrect parsing of paths referenced by $ref.

Oct 12 '22 07:10 mugioka

npx @redocly/cli bundle openapi.yaml successfully parse the correct $ref, but openapi-generator-cli generate -i openapi.yaml -g k6 --skip-validate-spec -o ./test failed to parse the correct $ref.

Oct 12 '22 07:10 mugioka

but openapi-generator-cli generate -i openapi.yaml -g k6 --skip-validate-spec -o ./test-v failed to parse the correct $ref.

can you please open an issue with details for tracking? I will try to take a look later.

Oct 16 '22 08:10 wing328

closing it as there's no update. please open a new one if needed. thanks.

Dec 21 '22 06:12 wing328