Support for OffsetDateTime

Needed this so wrote my own (pasted below). I also was unable to use this library because graphql-java doesn’t allow clients to change the scalar name (I wanted a Java LocalDate to be called just Date as a scalar in graphql).

This more closely matches the behavior I expect https://www.npmjs.com/package/graphql-iso-date to have wrt its Date and DateTime scalars.

    // example: 2007-12-03T10:15:30+01:00
    // example: 2007-12-03T10:15:30Z
    public static final GraphQLScalarType OFFSET_DATE_TIME_TYPE = new GraphQLScalarType("Timestamp",
            "A Java OffsetDateTime",
            new Coercing<OffsetDateTime, String>() {
                private OffsetDateTime convertImpl(Object input) {
                    if (input instanceof String) {
                        try {
                            return OffsetDateTime.parse((String) input, DateTimeFormatter.ISO_OFFSET_DATE_TIME);
                        } catch (DateTimeParseException ignored) {
                            return null;
                        }
                    }
                    return null;
                }

                @Override
                public String serialize(Object input) {
                    if (input instanceof OffsetDateTime) {
                        return DateTimeFormatter.ISO_OFFSET_DATE_TIME.format((OffsetDateTime) input);
                    } else {
                        OffsetDateTime result = convertImpl(input);
                        if (result == null) {
                            throw new CoercingSerializeException(
                                    "Invalid value '" + input + "' for Timestamp (a Java OffsetDateTime)");
                        }
                        return DateTimeFormatter.ISO_OFFSET_DATE_TIME.format(result);
                    }
                }

                @Override
                public OffsetDateTime parseValue(Object input) {
                    OffsetDateTime result = convertImpl(input);
                    if (result == null) {
                        throw new CoercingParseValueException(
                                "Invalid value '" + input + "' for Timestamp (a Java OffsetDateTime)");
                    }
                    return result;
                }

                @Override
                public OffsetDateTime parseLiteral(Object input) {
                    if (!(input instanceof StringValue)) {
                        return null;
                    }
                    String value = ((StringValue) input).getValue();
                    OffsetDateTime result = convertImpl(value);
                    return result;
                }
            });

    // example: 2012-01-05
    public static final GraphQLScalarType LOCAL_DATE_TYPE = new GraphQLScalarType("Date", "A Java LocalDate",
            new Coercing<LocalDate, String>() {
                private LocalDate convertImpl(Object input) {
                    if (input instanceof String) {
                        try {
                            return LocalDate.parse((String) input, DateTimeFormatter.ISO_LOCAL_DATE);
                        } catch (DateTimeParseException ignored) {
                            return null;
                        }
                    }
                    return null;
                }

                @Override
                public String serialize(Object input) {
                    if (input instanceof LocalDate) {
                        return DateTimeFormatter.ISO_LOCAL_DATE.format((LocalDate) input);
                    } else {
                        LocalDate result = convertImpl(input);
                        if (result == null) {
                            throw new CoercingSerializeException(
                                    "Invalid value '" + input + "' for Date (a Java LocalDate)");
                        }
                        return DateTimeFormatter.ISO_LOCAL_DATE.format(result);
                    }
                }

                @Override
                public LocalDate parseValue(Object input) {
                    LocalDate result = convertImpl(input);
                    if (result == null) {
                        throw new CoercingParseValueException(
                                "Invalid value '" + input + "' for Date (a Java LocalDate)");
                    }
                    return result;
                }

                @Override
                public LocalDate parseLiteral(Object input) {
                    if (!(input instanceof StringValue)) {
                        return null;
                    }
                    String value = ((StringValue) input).getValue();
                    LocalDate result = convertImpl(value);
                    return result;
                }
            });

[donbeave]

(I wanted a Java LocalDate to be called just Date as a scalar in graphql).

Can not, because some people want to use as Date and some want to use as LocalDate.

I’ll add OffsetDateTime as a new scalar also.

[donbeave]

Released: https://bintray.com/donbeave/maven/graphql-java-datetime/1.5.0