Allow more flexible Duration binding

Extend `BinderConversionService` to support `Duration` parsing of
the more readable `10s` form (equivalent to 10 seconds). Standard
ISO-8601 parsing also remains as an option.

Fixes gh-11078

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/properties/bind/convert/BinderConversionService.java

@@ -107,6 +107,7 @@ public class BinderConversionService implements ConversionService {
 		service.addConverter(new StringToInetAddressConverter());
 		service.addConverter(new InetAddressToStringConverter());
 		service.addConverter(new PropertyEditorConverter());
+		service.addConverter(new StringToDurationConverter());
 		DateFormatterRegistrar registrar = new DateFormatterRegistrar();
 		DateFormatter formatter = new DateFormatter();
 		formatter.setIso(DateTimeFormat.ISO.DATE_TIME);

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/properties/bind/convert/StringToDurationConverter.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright 2012-2017 the original author or authors.
+ *
+ * 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 org.springframework.boot.context.properties.bind.convert;
+
+import java.time.Duration;
+import java.time.temporal.ChronoUnit;
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.util.Assert;
+
+/**
+ * {@link Converter} for {@link String} to {@link Duration}. Support
+ * {@link Duration#parse(CharSequence)} as well a more readable {@code 10s} form.
+ *
+ * @author Phillip Webb
+ */
+class StringToDurationConverter implements Converter<String, Duration> {
+
+	private static Pattern ISO8601 = Pattern.compile("^[\\+\\-]?P.*$");
+
+	private static Pattern SIMPLE = Pattern.compile("^([\\+\\-]?\\d+)([a-zA-Z]{1,2})$");
+
+	private static final Map<String, ChronoUnit> UNITS;
+
+	static {
+		Map<String, ChronoUnit> units = new LinkedHashMap<>();
+		units.put("ns", ChronoUnit.NANOS);
+		units.put("ms", ChronoUnit.MILLIS);
+		units.put("s", ChronoUnit.SECONDS);
+		units.put("m", ChronoUnit.MINUTES);
+		units.put("h", ChronoUnit.HOURS);
+		units.put("d", ChronoUnit.DAYS);
+		UNITS = Collections.unmodifiableMap(units);
+	}
+
+	@Override
+	public Duration convert(String source) {
+		try {
+			if (ISO8601.matcher(source).matches()) {
+				return Duration.parse(source);
+			}
+			Matcher matcher = SIMPLE.matcher(source);
+			Assert.state(matcher.matches(), "'" + source + "' is not a valid duration");
+			long amount = Long.parseLong(matcher.group(1));
+			ChronoUnit unit = getUnit(matcher.group(2));
+			return Duration.of(amount, unit);
+		}
+		catch (Exception ex) {
+			throw new IllegalStateException("'" + source + "' is not a valid duration",
+					ex);
+		}
+	}
+
+	private ChronoUnit getUnit(String value) {
+		ChronoUnit unit = UNITS.get(value.toLowerCase());
+		Assert.state(unit != null, "Unknown unit '" + value + "'");
+		return unit;
+	}
+
+}

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/convert/BinderConversionServiceTests.java

@@ -18,6 +18,7 @@ package org.springframework.boot.context.properties.bind.convert;
 
 import java.io.InputStream;
 import java.net.InetAddress;
+import java.time.Duration;
 
 import org.junit.Before;
 import org.junit.Test;
@@ -153,6 +154,13 @@ public class BinderConversionServiceTests {
 		assertThat(converted).isEqualTo(InputStream.class);
 	}
 
+	@Test
+	public void conversionServiceShouldSupportStringToDuration() throws Exception {
+		this.service = new BinderConversionService(null);
+		Duration converted = this.service.convert("10s", Duration.class);
+		assertThat(converted).isEqualTo(Duration.ofSeconds(10));
+	}
+
 	enum TestEnum {
 
 		ONE, TWO

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/convert/StringToDurationConverterTests.java

@@ -0,0 +1,111 @@
+/*
+ * Copyright 2012-2017 the original author or authors.
+ *
+ * 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 org.springframework.boot.context.properties.bind.convert;
+
+import java.time.Duration;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link StringToDurationConverter}.
+ *
+ * @author Phillip Webb
+ */
+public class StringToDurationConverterTests {
+
+	@Rule
+	public ExpectedException thrown = ExpectedException.none();
+
+	private StringToDurationConverter converter = new StringToDurationConverter();
+
+	@Test
+	public void convertWhenIso8601ShouldReturnDuration() throws Exception {
+		assertThat(convert("PT20.345S")).isEqualTo(Duration.parse("PT20.345S"));
+		assertThat(convert("PT15M")).isEqualTo(Duration.parse("PT15M"));
+		assertThat(convert("+PT15M")).isEqualTo(Duration.parse("PT15M"));
+		assertThat(convert("PT10H")).isEqualTo(Duration.parse("PT10H"));
+		assertThat(convert("P2D")).isEqualTo(Duration.parse("P2D"));
+		assertThat(convert("P2DT3H4M")).isEqualTo(Duration.parse("P2DT3H4M"));
+		assertThat(convert("P2DT3H4M")).isEqualTo(Duration.parse("P2DT3H4M"));
+		assertThat(convert("-PT6H3M")).isEqualTo(Duration.parse("-PT6H3M"));
+		assertThat(convert("-PT-6H+3M")).isEqualTo(Duration.parse("-PT-6H+3M"));
+	}
+
+	@Test
+	public void convertWhenSimpleNanosShouldReturnDuration() {
+		assertThat(convert("10ns")).isEqualTo(Duration.ofNanos(10));
+		assertThat(convert("10NS")).isEqualTo(Duration.ofNanos(10));
+		assertThat(convert("+10ns")).isEqualTo(Duration.ofNanos(10));
+		assertThat(convert("-10ns")).isEqualTo(Duration.ofNanos(-10));
+	}
+
+	@Test
+	public void convertWhenSimpleMillisShouldReturnDuration() {
+		assertThat(convert("10ms")).isEqualTo(Duration.ofMillis(10));
+		assertThat(convert("10MS")).isEqualTo(Duration.ofMillis(10));
+		assertThat(convert("+10ms")).isEqualTo(Duration.ofMillis(10));
+		assertThat(convert("-10ms")).isEqualTo(Duration.ofMillis(-10));
+	}
+
+	@Test
+	public void convertWhenSimpleSecondsShouldReturnDuration() {
+		assertThat(convert("10s")).isEqualTo(Duration.ofSeconds(10));
+		assertThat(convert("10S")).isEqualTo(Duration.ofSeconds(10));
+		assertThat(convert("+10s")).isEqualTo(Duration.ofSeconds(10));
+		assertThat(convert("-10s")).isEqualTo(Duration.ofSeconds(-10));
+	}
+
+	@Test
+	public void convertWhenSimpleMinutesShouldReturnDuration() {
+		assertThat(convert("10m")).isEqualTo(Duration.ofMinutes(10));
+		assertThat(convert("10M")).isEqualTo(Duration.ofMinutes(10));
+		assertThat(convert("+10m")).isEqualTo(Duration.ofMinutes(10));
+		assertThat(convert("-10m")).isEqualTo(Duration.ofMinutes(-10));
+	}
+
+	@Test
+	public void convertWhenSimpleHoursShouldReturnDuration() {
+		assertThat(convert("10h")).isEqualTo(Duration.ofHours(10));
+		assertThat(convert("10H")).isEqualTo(Duration.ofHours(10));
+		assertThat(convert("+10h")).isEqualTo(Duration.ofHours(10));
+		assertThat(convert("-10h")).isEqualTo(Duration.ofHours(-10));
+	}
+
+	@Test
+	public void convertWhenSimpleDaysShouldReturnDuration() {
+		assertThat(convert("10d")).isEqualTo(Duration.ofDays(10));
+		assertThat(convert("10D")).isEqualTo(Duration.ofDays(10));
+		assertThat(convert("+10d")).isEqualTo(Duration.ofDays(10));
+		assertThat(convert("-10d")).isEqualTo(Duration.ofDays(-10));
+	}
+
+	@Test
+	public void convertWhenBadFormatShouldThrowException() throws Exception {
+		this.thrown.expect(IllegalStateException.class);
+		this.thrown.expectMessage("'10foo' is not a valid duration");
+		convert("10foo");
+	}
+
+	private Duration convert(String source) {
+		return this.converter.convert(source);
+	}
+
+}