Implied type error when generating OpenAPI tests

[tarsiswt]

I'm having some trouble trying to use tcases-api-test to generate some tests for the Pix API (a brazillian payment system). The OpenAPI specification is at https://github.com/bacen/pix-api/releases/download/2.6.3/spec.yaml.

When running tcases 3.8.4 via command line wih

tcases-api-test spec.yaml

I get the following exception in the console

org.cornutum.tcases.openapi.OpenApiException: Error processing API Pix, /cob/{txid}, PATCH, requestBody, application/json, allOf, infoAdicionais
        at org.cornutum.tcases.openapi.OpenApiContext.whenFailure(OpenApiContext.java:24)
        at org.cornutum.tcases.openapi.OpenApiContext.whenFailure(OpenApiContext.java:13)
        at org.cornutum.tcases.openapi.ExecutionContext.resultFor(ExecutionContext.java:34)
        at org.cornutum.tcases.openapi.ConditionReporter.resultFor(ConditionReporter.java:70)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.lambda$null$12(SchemaAnalyzer.java:138)
        at java.base/java.util.Iterator.forEachRemaining(Iterator.java:133)
        at java.base/java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1845)
        at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:762)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.lambda$resolveProperties$13(SchemaAnalyzer.java:138)
        at java.base/java.util.Optional.ifPresent(Optional.java:178)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.resolveProperties(SchemaAnalyzer.java:136)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.resolve(SchemaAnalyzer.java:87)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.lambda$null$4(SchemaAnalyzer.java:104)
        at org.cornutum.tcases.openapi.ExecutionContext.resultFor(ExecutionContext.java:30)
        at org.cornutum.tcases.openapi.ConditionReporter.resultFor(ConditionReporter.java:70)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.lambda$resolveMembers$5(SchemaAnalyzer.java:104)
        at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
        at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)
        at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
        at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
        at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921)
        at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
        at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.resolveMembers(SchemaAnalyzer.java:105)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.lambda$resolve$2(SchemaAnalyzer.java:82)
        at java.base/java.util.Optional.ifPresent(Optional.java:178)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.resolve(SchemaAnalyzer.java:82)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.analyze(SchemaAnalyzer.java:57)
        at org.cornutum.tcases.openapi.InputModeller.analyzeSchema(InputModeller.java:3824)
        at org.cornutum.tcases.openapi.InputModeller.lambda$null$30(InputModeller.java:544)
        at org.cornutum.tcases.openapi.ExecutionContext.resultFor(ExecutionContext.java:30)
        at org.cornutum.tcases.openapi.ConditionReporter.resultFor(ConditionReporter.java:70)
        at org.cornutum.tcases.openapi.InputModeller.lambda$mediaTypeContentVars$31(InputModeller.java:537)
        at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
        at java.base/java.util.Iterator.forEachRemaining(Iterator.java:133)
        at java.base/java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1845)
        at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
        at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
        at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
        at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
        at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
        at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)
        at org.cornutum.tcases.VarSetBuilder.members(VarSetBuilder.java:150)
        at org.cornutum.tcases.openapi.InputModeller.lambda$null$21(InputModeller.java:466)
        at java.base/java.util.Optional.map(Optional.java:260)
        at org.cornutum.tcases.openapi.InputModeller.lambda$requestBodyVarDef$22(InputModeller.java:457)
        at org.cornutum.tcases.openapi.ExecutionContext.resultFor(ExecutionContext.java:30)
        at org.cornutum.tcases.openapi.ConditionReporter.resultFor(ConditionReporter.java:70)
        at org.cornutum.tcases.openapi.InputModeller.requestBodyVarDef(InputModeller.java:453)
        at org.cornutum.tcases.openapi.InputModeller.opRequestVars(InputModeller.java:267)
        at org.cornutum.tcases.openapi.InputModeller.lambda$opRequestDef$6(InputModeller.java:252)
        at org.cornutum.tcases.openapi.ExecutionContext.resultFor(ExecutionContext.java:30)
        at org.cornutum.tcases.openapi.ConditionReporter.resultFor(ConditionReporter.java:70)
        at org.cornutum.tcases.openapi.InputModeller.opRequestDef(InputModeller.java:242)
        at org.cornutum.tcases.openapi.InputModeller.lambda$pathRequestDefs$4(InputModeller.java:206)
        at org.cornutum.tcases.openapi.ExecutionContext.resultFor(ExecutionContext.java:30)
        at org.cornutum.tcases.openapi.ConditionReporter.resultFor(ConditionReporter.java:70)
        at org.cornutum.tcases.openapi.InputModeller.pathRequestDefs(InputModeller.java:196)
        at org.cornutum.tcases.openapi.InputModeller.lambda$null$0(InputModeller.java:144)
        at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:273)
        at java.base/java.util.Iterator.forEachRemaining(Iterator.java:133)
        at java.base/java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1845)
        at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
        at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
        at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
        at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
        at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
        at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)
        at org.cornutum.tcases.SystemInputDefBuilder.functions(SystemInputDefBuilder.java:119)
        at org.cornutum.tcases.openapi.InputModeller.lambda$requestSchemasModel$1(InputModeller.java:144)
        at org.cornutum.tcases.openapi.ExecutionContext.resultFor(ExecutionContext.java:30)
        at org.cornutum.tcases.openapi.ConditionReporter.resultFor(ConditionReporter.java:70)
        at org.cornutum.tcases.openapi.InputModeller.requestSchemasModel(InputModeller.java:137)
        at org.cornutum.tcases.openapi.InputModeller.requestInputModel(InputModeller.java:115)
        at org.cornutum.tcases.openapi.RequestInputModeller.getRequestInputModel(RequestInputModeller.java:43)
        at org.cornutum.tcases.openapi.TcasesOpenApi.getRequestInputModel(TcasesOpenApi.java:44)
        at org.cornutum.tcases.openapi.io.TcasesOpenApiIO.getRequestInputModel(TcasesOpenApiIO.java:98)
        at org.cornutum.tcases.openapi.ApiTestCommand.run(ApiTestCommand.java:1771)
        at org.cornutum.tcases.openapi.ApiTestCommand.main(ApiTestCommand.java:1732)
Caused by: java.lang.IllegalStateException: Schema declares type=array but has implied type=number
        at org.cornutum.tcases.openapi.SchemaUtils.resolveSchemaType(SchemaUtils.java:242)
        at org.cornutum.tcases.openapi.OpenApiUtils.resolveSchema(OpenApiUtils.java:135)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.resolve(SchemaAnalyzer.java:72)
        at org.cornutum.tcases.openapi.SchemaAnalyzer.lambda$null$11(SchemaAnalyzer.java:138)
        at org.cornutum.tcases.openapi.ExecutionContext.resultFor(ExecutionContext.java:30)
        ... 76 more

and the tcases-api-test.log file has the following logs

08:33:37.936 INFO  o.c.t.openapi.ApiTestCommand - Tcases 3.8.4 (2022-10-20)
08:33:37.939 INFO  o.c.t.openapi.ApiTestCommand - Reading API definition from spec.yaml
08:33:38.386 ERROR o.c.tcases.openapi.InputModeller - API Pix,/cob/{txid},GET,security,OAuth2: Security type=oauth2 is not supported in this version. Generated tests will not provide this type of authentication.
08:33:38.406 WARN  o.c.tcases.openapi.InputModeller - API Pix,/cob/{txid},GET,txid: Empty string values not allowed for non-nullable parameter -- using minLength=1.
08:33:38.439 WARN  o.c.tcases.openapi.InputModeller - API Pix,/cob/{txid},GET,txid: minLength=1 is below the minimum allowed for pattern matches -- using minLength=26 instead.
08:33:38.490 ERROR o.c.tcases.openapi.InputModeller - API Pix,/cob/{txid},PUT,requestBody,application/json,devedor,nome: minLength=201 is greater than maxLength=200. Adjusting minLength to maxLength.
08:33:38.493 ERROR o.c.tcases.openapi.InputModeller - API Pix,/cob/{txid},PUT,requestBody,application/json,devedor,nome: minLength=201 is greater than maxLength=200. Adjusting minLength to maxLength.
08:33:38.577 ERROR o.c.tcases.openapi.InputModeller - API Pix,/cob/{txid},PUT,security,OAuth2: Security type=oauth2 is not supported in this version. Generated tests will not provide this type of authentication.
08:33:38.578 WARN  o.c.tcases.openapi.InputModeller - API Pix,/cob/{txid},PUT,txid: minLength=1 is below the minimum allowed for pattern matches -- using minLength=26 instead.

Judging by the content of the error messages it looks like tcases computed the implied type of the infoAdicionais to be number. Could this be happening because the CobRevisada schema uses a combinatino of allOf and $ref?

    CobRevisada:
      # ...
      allOf:
      # ...
        - $ref: "#/components/schemas/CobBase"

Can you help me understand why that is and what I could do to make such specification amenable to tcases?

[kerrykimbrough]

Your guess was close to the answer. The problem occurs in the schema for CoBase. The infoAdicionais property is defined to be type array but also specifies the maximum keyword, which implies a type of number or integer. See below.

Perhaps this was intended to be maxItems: 50?

...
 4647          infoAdicionais:
 4648            type: array
 4649            title: Informações adicionais
 4650            description: >-
 4651              Cada respectiva informação adicional contida na lista (nome e valor)
 4652              deve ser apresentada ao pagador.
 4653            maximum: 50
 4654            items:
 4655              type: object
...

[tarsiswt]

That's exactly right. Thank you so much!

[kerrykimbrough]

This discussion has been helpful because it has demonstrated that the message for this error is not as clear as it should be. The next release, which is coming soon, will improve this. The new message will look like this:

Error processing API Pix, /cob/{txid}, PATCH, requestBody, application/json, allOf, infoAdicionais
...
Caused by: ...Schema declares type=array but defines property=maximum which implies type=number