[#19921] Add RFC 3339 compatible Jackson module for java.time types

Author: beikov

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

@@ -678,6 +678,8 @@ public void processOpts() {
                 additionalProperties.remove(SERIALIZATION_LIBRARY_GSON);
                 additionalProperties.remove(SERIALIZATION_LIBRARY_JSONB);
                 supportingFiles.add(new SupportingFile("RFC3339DateFormat.mustache", invokerFolder, "RFC3339DateFormat.java"));
+                supportingFiles.add(new SupportingFile("RFC3339InstantDeserializer.mustache", invokerFolder, "RFC3339InstantDeserializer.java"));
+                supportingFiles.add(new SupportingFile("RFC3339JavaTimeModule.mustache", invokerFolder, "RFC3339JavaTimeModule.java"));
                 break;
             case SERIALIZATION_LIBRARY_GSON:
                 additionalProperties.put(SERIALIZATION_LIBRARY_GSON, "true");

modules/openapi-generator/src/main/resources/Java/RFC3339InstantDeserializer.mustache

@@ -0,0 +1,74 @@
+{{>licenseInfo}}
+package {{invokerPackage}};
+
+import java.io.IOException;
+import java.time.Instant;
+import java.time.OffsetDateTime;
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+import java.time.temporal.Temporal;
+import java.time.temporal.TemporalAccessor;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.datatype.jsr310.deser.InstantDeserializer;
+
+{{>generatedAnnotation}}
+public class RFC3339InstantDeserializer<T extends Temporal> extends InstantDeserializer<T> {
+
+    public static final RFC3339InstantDeserializer<Instant> INSTANT = new RFC3339InstantDeserializer<>(
+        Instant.class, DateTimeFormatter.ISO_INSTANT,
+        Instant::from,
+        a -> Instant.ofEpochMilli( a.value ),
+        a -> Instant.ofEpochSecond( a.integer, a.fraction ),
+        null,
+        true // yes, replace zero offset with Z
+    );
+
+    public static final RFC3339InstantDeserializer<OffsetDateTime> OFFSET_DATE_TIME = new RFC3339InstantDeserializer<>(
+        OffsetDateTime.class, DateTimeFormatter.ISO_OFFSET_DATE_TIME,
+        OffsetDateTime::from,
+        a -> OffsetDateTime.ofInstant( Instant.ofEpochMilli( a.value ), a.zoneId ),
+        a -> OffsetDateTime.ofInstant( Instant.ofEpochSecond( a.integer, a.fraction ), a.zoneId ),
+        (d, z) -> ( d.isEqual( OffsetDateTime.MIN ) || d.isEqual( OffsetDateTime.MAX ) ?
+        d :
+        d.withOffsetSameInstant( z.getRules().getOffset( d.toLocalDateTime() ) ) ),
+        true // yes, replace zero offset with Z
+    );
+
+    public static final RFC3339InstantDeserializer<ZonedDateTime> ZONED_DATE_TIME = new RFC3339InstantDeserializer<>(
+        ZonedDateTime.class, DateTimeFormatter.ISO_ZONED_DATE_TIME,
+        ZonedDateTime::from,
+        a -> ZonedDateTime.ofInstant( Instant.ofEpochMilli( a.value ), a.zoneId ),
+        a -> ZonedDateTime.ofInstant( Instant.ofEpochSecond( a.integer, a.fraction ), a.zoneId ),
+        ZonedDateTime::withZoneSameInstant,
+        false // keep zero offset and Z separate since zones explicitly supported
+    );
+
+    protected RFC3339InstantDeserializer(
+            Class<T> supportedType,
+            DateTimeFormatter formatter,
+            Function<TemporalAccessor, T> parsedToValue,
+            Function<FromIntegerArguments, T> fromMilliseconds,
+            Function<FromDecimalArguments, T> fromNanoseconds,
+            BiFunction<T, ZoneId, T> adjust,
+            boolean replaceZeroOffsetAsZ) {
+        super(
+                supportedType,
+                formatter,
+                parsedToValue,
+                fromMilliseconds,
+                fromNanoseconds,
+                adjust,
+                replaceZeroOffsetAsZ
+        );
+    }
+
+    @Override
+    protected T _fromString(JsonParser p, DeserializationContext ctxt, String string0) throws IOException {
+        return super._fromString(p, ctxt, string0.replace( ' ', 'T' ));
+    }
+}

modules/openapi-generator/src/main/resources/Java/RFC3339JavaTimeModule.mustache

@@ -0,0 +1,20 @@
+{{>licenseInfo}}
+package {{invokerPackage}};
+
+import java.time.Instant;
+import java.time.OffsetDateTime;
+import java.time.ZonedDateTime;
+
+import com.fasterxml.jackson.databind.module.SimpleModule;
+
+{{>generatedAnnotation}}
+public class RFC3339JavaTimeModule extends SimpleModule {
+
+    public RFC3339JavaTimeModule() {
+        super("RFC3339JavaTimeModule");
+
+        addDeserializer(Instant.class, RFC3339InstantDeserializer.INSTANT);
+        addDeserializer(OffsetDateTime.class, RFC3339InstantDeserializer.OFFSET_DATE_TIME);
+        addDeserializer(ZonedDateTime.class, RFC3339InstantDeserializer.ZONED_DATE_TIME);
+    }
+}

modules/openapi-generator/src/main/resources/Java/libraries/apache-httpclient/ApiClient.mustache

@@ -149,6 +149,7 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
     {{#openApiNullable}}
     objectMapper.registerModule(new JsonNullableModule());
     {{/openApiNullable}}
+    objectMapper.registerModule(new RFC3339JavaTimeModule());
     objectMapper.setDateFormat(ApiClient.buildDefaultDateFormat());
 
     dateFormat = ApiClient.buildDefaultDateFormat();

modules/openapi-generator/src/main/resources/Java/libraries/feign/ApiClient.mustache

@@ -187,6 +187,7 @@ public class ApiClient {
     {{/joda}}
     objectMapper.registerModule(new JavaTimeModule());
     {{#openApiNullable}}
+    objectMapper.registerModule(new RFC3339JavaTimeModule());
     JsonNullableModule jnm = new JsonNullableModule();
     objectMapper.registerModule(jnm);
     {{/openApiNullable}}

modules/openapi-generator/src/main/resources/Java/libraries/jersey2/JSON.mustache

@@ -45,6 +45,7 @@ public class JSON implements ContextResolver<ObjectMapper> {
             {{#openApiNullable}}
             .addModule(new JsonNullableModule())
             {{/openApiNullable}}
+            .addModule(new RFC3339JavaTimeModule())
             .build();
   }
 

modules/openapi-generator/src/main/resources/Java/libraries/jersey3/JSON.mustache

@@ -45,6 +45,7 @@ public class JSON implements ContextResolver<ObjectMapper> {
             {{#openApiNullable}}
             .addModule(new JsonNullableModule())
             {{/openApiNullable}}
+            .addModule(new RFC3339JavaTimeModule())
             .build();
   }
 

modules/openapi-generator/src/main/resources/Java/libraries/native/ApiClient.mustache

@@ -196,6 +196,7 @@ public class ApiClient {
     {{#openApiNullable}}
     mapper.registerModule(new JsonNullableModule());
     {{/openApiNullable}}
+    mapper.registerModule(new RFC3339JavaTimeModule());
     return mapper;
   }
 

modules/openapi-generator/src/test/java/org/openapitools/codegen/java/JavaClientCodegenTest.java

@@ -519,7 +519,7 @@ public void testSupportedSecuritySchemesJersey() {
 
         List<File> files = new DefaultGenerator().opts(configurator.toClientOptInput()).generate();
 
-        assertThat(files).hasSize(32);
+        assertThat(files).hasSize(34);
         validateJavaSourceFiles(files);
         assertThat(output.resolve("src/main/java/xyz/abcdef/api/DefaultApi.java")).content().contains(
             "public class DefaultApi", 
@@ -586,7 +586,7 @@ public void testSupportedSecuritySchemesJersey() {
 
         List<File> files = new DefaultGenerator().opts(configurator.toClientOptInput()).generate();
 
-        assertThat(files).hasSize(35);
+        assertThat(files).hasSize(37);
 
         validateJavaSourceFiles(files);
         assertThat(output.resolve("src/main/java/xyz/abcdef/api/PingApi.java")).content().contains(
@@ -1389,7 +1389,7 @@ public void testRestTemplateWithFreeFormInQueryParameters() {
         List<File> files = new DefaultGenerator().opts(configurator.toClientOptInput()).generate();
 
         validateJavaSourceFiles(files);
-        assertThat(files).hasSize(35);
+        assertThat(files).hasSize(37);
         TestUtils.assertFileContains(output.resolve("src/main/java/xyz/abcdef/ApiClient.java"),
             "public static String urlEncode(String s) { return URLEncoder.encode(s,"
                 + " UTF_8).replaceAll(\"\\\\+\", \"%20\"); }"
@@ -1411,7 +1411,7 @@ public void testRestTemplateWithFreeFormInQueryParameters() {
         List<File> files = new DefaultGenerator().opts(configurator.toClientOptInput()).generate();
 
         validateJavaSourceFiles(files);
-        assertThat(files).hasSize(38);
+        assertThat(files).hasSize(40);
         assertThat(output.resolve("src/main/java/xyz/abcdef/api/DefaultApi.java")).content()
             .contains(
                 "localVarQueryParams.addAll(ApiClient.parameterToPairs(\"since\", queryObject.getSince()));",

modules/openapi-generator/src/test/java/org/openapitools/codegen/java/apachehttpclient/ApacheHttpClientCodegenTest.java

@@ -56,7 +56,7 @@ public void testApacheHttpClientExplodedQueryParamObject() throws IOException {
         DefaultGenerator generator = new DefaultGenerator();
         List<File> files = generator.opts(clientOptInput).generate();
 
-        Assert.assertEquals(files.size(), 42);
+        Assert.assertEquals(files.size(), 44);
         validateJavaSourceFiles(files);
 
         TestUtils.assertFileContains(Paths.get(output + "/src/main/java/xyz/abcdef/api/DefaultApi.java"),