io.trino.client.uri.AbstractConnectionProperty Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of trino-client Show documentation
Trino - Client
There is a newer version: 468
/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package io.trino.client.uri;

import com.google.common.reflect.TypeToken;

import java.io.File;
import java.nio.file.Paths;
import java.util.Optional;
import java.util.Properties;
import java.util.function.Function;
import java.util.function.Predicate;
import java.util.stream.Stream;

import static com.google.common.base.Preconditions.checkArgument;
import static java.lang.String.format;
import static java.util.Locale.ENGLISH;
import static java.util.Objects.requireNonNull;
import static java.util.function.Function.identity;

abstract class AbstractConnectionProperty
        implements ConnectionProperty
{
    private final PropertyName propertyName;
    private final String key;
    private final Optional defaultValue;
    private final Predicate isRequired;
    private final Validator validator;
    private final Converter converter;
    private final String[] choices;

    protected AbstractConnectionProperty(
            PropertyName propertyName,
            Optional defaultValue,
            Predicate isRequired,
            Validator validator,
            Converter converter)
    {
        this.propertyName = requireNonNull(propertyName, "key is null");
        this.key = propertyName.toString();
        this.defaultValue = requireNonNull(defaultValue, "defaultValue is null");
        this.isRequired = requireNonNull(isRequired, "isRequired is null");
        this.validator = requireNonNull(validator, "validator is null");
        this.converter = requireNonNull(converter, "converter is null");

        Class type = new TypeToken(getClass()) {}.getRawType();
        if (type == Boolean.class) {
            choices = new String[] {"true", "false"};
        }
        else if (Enum.class.isAssignableFrom(type)) {
            choices = Stream.of(type.getEnumConstants())
                    .map(Object::toString)
                    .toArray(String[]::new);
        }
        else {
            choices = null;
        }
    }

    protected AbstractConnectionProperty(
            PropertyName key,
            Predicate required,
            Validator allowed,
            Converter converter)
    {
        this(key, Optional.empty(), required, allowed, converter);
    }

    @Override
    public PropertyName getPropertyName()
    {
        return propertyName;
    }

    @Override
    public boolean isRequired(Properties properties)
    {
        return isRequired.test(properties);
    }

    @Override
    public Optional getValue(Properties properties)
    {
        Object value = properties.get(key);
        if (value == null) {
            if (isRequired(properties) && !defaultValue.isPresent()) {
                throw new RuntimeException(format("Connection property %s is required", key));
            }
            return defaultValue;
        }

        try {
            return Optional.of(decodeValue((V) value));
        }
        catch (RuntimeException e) {
            if (isEmpty(value)) {
                throw new RuntimeException(format("Connection property %s value is empty", key), e);
            }
            throw new RuntimeException(format("Connection property %s value is invalid: %s", key, value), e);
        }
    }

    @Override
    public V encodeValue(T value)
    {
        return converter.encode(value);
    }

    @Override
    public T decodeValue(V value)
    {
        return converter.decode(value);
    }

    @Override
    public String[] getChoices()
    {
        return choices;
    }

    @Override
    public Optional validate(Properties properties)
    {
        if (properties.containsKey(key)) {
            Optional message = validator.validate(properties);
            if (message.isPresent()) {
                return message.map(RuntimeException::new);
            }
        }

        try {
            getValue(properties);
        }
        catch (RuntimeException e) {
            return Optional.of(e);
        }

        return Optional.empty();
    }

    private boolean isEmpty(Object value)
    {
        if (value == null) {
            return true;
        }
        if (value instanceof String) {
            return ((String) value).isEmpty();
        }
        return false;
    }

    protected static final Predicate NOT_REQUIRED = properties -> false;

    protected static final Validator ALLOWED = properties -> Optional.empty();

    interface Converter
    {
        T decode(V value);

        V encode(T value);
    }

    protected static  Converter converter(Function decoder, Function encoder)
    {
        return new Converter()
        {
            @Override
            public T decode(V value)
            {
                return decoder.apply(value);
            }

            @Override
            public V encode(T value)
            {
                return encoder.apply(value);
            }
        };
    }

    protected static final Converter STRING_CONVERTER = converter(identity(), identity());

    protected static final Converter NON_EMPTY_STRING_CONVERTER = new Converter()
    {
        @Override
        public String decode(String value)
        {
            checkArgument(!value.isEmpty(), "value is empty");
            return value;
        }

        @Override
        public String encode(String value)
        {
            return value;
        }
    };

    protected static final Converter FILE_CONVERTER = new Converter()
    {
        @Override
        public File decode(String value)
        {
            return Paths.get(value).toFile();
        }

        @Override
        public String encode(File value)
        {
            return value.getPath();
        }
    };

    protected static final Converter BOOLEAN_CONVERTER = new Converter()
    {
        @Override
        public Boolean decode(String value)
        {
            switch (value.toLowerCase(ENGLISH)) {
                case "true":
                    return true;
                case "false":
                    return false;
            }

            throw new IllegalArgumentException("value must be 'true' or 'false'");
        }

        @Override
        public String encode(Boolean value)
        {
            return value.toString();
        }
    };

    protected interface Validator
    {
        /**
         * @param value Value to validate
         * @return An error message if the value is invalid or empty otherwise
         */
        Optional validate(T value);

        default Validator and(Validator other)
        {
            requireNonNull(other, "other is null");
            // return the first non-empty optional
            return t -> {
                Optional result = validate(t);
                if (result.isPresent()) {
                    return result;
                }
                return other.validate(t);
            };
        }
    }

    protected static  Validator validator(Predicate predicate, String errorMessage)
    {
        requireNonNull(predicate, "predicate is null");
        requireNonNull(errorMessage, "errorMessage is null");
        return value -> {
            if (predicate.test(value)) {
                return Optional.empty();
            }
            return Optional.of(errorMessage);
        };
    }
}