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Deserialization fails when schema.type attribute does not exist

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Stale
Tech stack
java
Domain
backend

Research direction

Reproduce the failure with ObjectMapper.readValue("{}", JsonSchema.class) and inspect JsonSchema's type handling alongside AnySchema. Add a regression test for an empty schema that expects AnySchema, then run the existing Maven test suite and confirm schemas with an explicit type still deserialize correctly.

Written by the indexing model from the issue text.

Description

Affects: 2.8.2
Issue

When trying to deserialize a JSON schema without attribute type, an exception is raised.
Relates to PR 110

Spec pointer

If the property is not defined or is not in this list, then any
type of value is acceptable.

I'd expect an empty JSON schema to be deserialized as AnySchema.

How to reproduce
POM file
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>fr.quilicicf.test</groupId>
    <artifactId>jackson-module-jsonSchema</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>com.fasterxml.jackson.module</groupId>
            <artifactId>jackson-module-jsonSchema</artifactId>
            <version>2.8.2</version>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
    </dependencies>
</project>
Java file
package fr.quilicicf.test;

import org.junit.Assert;
import org.junit.Test;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.module.jsonSchema.JsonSchema;
import com.fasterxml.jackson.module.jsonSchema.types.AnySchema;

public class JsonSchemaDeserialization {

    @Test
    public void test() throws Exception {
        JsonSchema jsonSchema = new ObjectMapper().readValue("{}", JsonSchema.class);
        Assert.assertTrue(jsonSchema instanceof AnySchema);
    }
}
Trace
com.fasterxml.jackson.databind.JsonMappingException: Unexpected token (END_OBJECT), expected FIELD_NAME: missing property 'type' that is to contain type id  (for class com.fasterxml.jackson.module.jsonSchema.JsonSchema)
 at [Source: {}; line: 1, column: 2]
    at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:261)
    at com.fasterxml.jackson.databind.DeserializationContext.wrongTokenException(DeserializationContext.java:1340)
    at com.fasterxml.jackson.databind.DeserializationContext.reportWrongTokenException(DeserializationContext.java:1196)
    at com.fasterxml.jackson.databind.jsontype.impl.AsPropertyTypeDeserializer._deserializeTypedUsingDefaultImpl(AsPropertyTypeDeserializer.java:157)
    at com.fasterxml.jackson.databind.jsontype.impl.AsPropertyTypeDeserializer.deserializeTypedFromObject(AsPropertyTypeDeserializer.java:105)
    at com.fasterxml.jackson.databind.deser.AbstractDeserializer.deserializeWithType(AbstractDeserializer.java:142)
    at com.fasterxml.jackson.databind.deser.impl.TypeWrappedDeserializer.deserialize(TypeWrappedDeserializer.java:63)
    at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:3789)
    at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2833)
    at fr.quilicicf.test.JsonSchemaDeserialization.test(JsonSchemaDeserialization.java:23)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Dominant language
Java
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Forks
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