Use System Property Proxy Settings for Netty and Amazon CRT HTTP Clients

http-clients/aws-crt-client/src/main/java/software/amazon/awssdk/http/crt/ProxyConfiguration.java

@@ -18,6 +18,7 @@
 import java.util.Objects;
 import software.amazon.awssdk.annotations.SdkPreviewApi;
 import software.amazon.awssdk.annotations.SdkPublicApi;
+import software.amazon.awssdk.utils.ProxySystemSetting;
 import software.amazon.awssdk.utils.builder.CopyableBuilder;
 import software.amazon.awssdk.utils.builder.ToCopyableBuilder;
 
@@ -39,11 +40,13 @@ public final class ProxyConfiguration implements ToCopyableBuilder<ProxyConfigur
 
     private final String username;
     private final String password;
+    private final Boolean useSystemPropertyValues;
 
     private ProxyConfiguration(BuilderImpl builder) {
+        this.useSystemPropertyValues = builder.useSystemPropertyValues;
         this.scheme = builder.scheme;
-        this.host = builder.host;
-        this.port = builder.port;
+        this.host = resolveHost(builder.host);
+        this.port = resolvePort(builder.port);
         this.username = builder.username;
         this.password = builder.password;
     }
@@ -56,31 +59,35 @@ public String scheme() {
     }
 
     /**
-     * @return The proxy host.
+     * @return The proxy host from the configuration if set, or from the "http.proxyHost" system property if
+     * {@link Builder#useSystemPropertyValues(Boolean)} is set to true
      */
     public String host() {
         return host;
     }
 
     /**
-     * @return The proxy port.
+     * @return The proxy port from the configuration if set, or from the "http.proxyPort" system property if
+     * {@link Builder#useSystemPropertyValues(Boolean)} is set to true
      */
     public int port() {
         return port;
     }
 
     /**
-     * @return Basic authentication username
-     */
+     * @return The proxy username from the configuration if set, or from the "http.proxyUser" system property if
+     * {@link Builder#useSystemPropertyValues(Boolean)} is set to true
+     * */
     public String username() {
-        return username;
+        return resolveValue(username, ProxySystemSetting.PROXY_USERNAME);
     }
 
     /**
-     * @return Basic authentication password
-     */
+     * @return The proxy password from the configuration if set, or from the "http.proxyPassword" system property if
+     * {@link Builder#useSystemPropertyValues(Boolean)} is set to true
+     * */
     public String password() {
-        return password;
+        return resolveValue(password, ProxySystemSetting.PROXY_PASSWORD);
     }
 
     @Override
@@ -182,19 +189,49 @@ public interface Builder extends CopyableBuilder<Builder, ProxyConfiguration> {
          * @return This object for method chaining.
          */
         Builder password(String password);
+
+        /**
+         * The option whether to use system property values from {@link ProxySystemSetting} if any of the config options
+         * are missing. The value is set to "true" by default which means SDK will automatically use system property values if
+         * options are not provided during building the {@link ProxyConfiguration} object. To disable this behaviour, set this
+         * value to false.
+         *
+         * @param useSystemPropertyValues The option whether to use system property values
+         * @return This object for method chaining.
+         */
+        Builder useSystemPropertyValues(Boolean useSystemPropertyValues);
+    }
+
+    private String resolveHost(String host) {
+        return resolveValue(host, ProxySystemSetting.PROXY_HOST);
+    }
+
+    private int resolvePort(int port) {
+        return port == 0 && Boolean.TRUE.equals(useSystemPropertyValues) ?
+               ProxySystemSetting.PROXY_PORT.getStringValue().map(Integer::parseInt).orElse(0) : port;
+    }
+
+    /**
+     * Uses the configuration options, system setting property and returns the final value of the given member.
+     */
+    private String resolveValue(String value, ProxySystemSetting systemSetting) {
+        return value == null && Boolean.TRUE.equals(useSystemPropertyValues) ?
+               systemSetting.getStringValue().orElse(null) : value;
     }
 
     private static final class BuilderImpl implements Builder {
         private String scheme;
         private String host;
-        private int port;
+        private int port = 0;
         private String username;
         private String password;
+        private Boolean useSystemPropertyValues = Boolean.TRUE;
 
         private BuilderImpl() {
         }
 
         private BuilderImpl(ProxyConfiguration proxyConfiguration) {
+            this.useSystemPropertyValues = proxyConfiguration.useSystemPropertyValues;
             this.scheme = proxyConfiguration.scheme;
             this.host = proxyConfiguration.host;
             this.port = proxyConfiguration.port;
@@ -232,6 +269,16 @@ public Builder password(String password) {
             return this;
         }
 
+        @Override
+        public Builder useSystemPropertyValues(Boolean useSystemPropertyValues) {
+            this.useSystemPropertyValues = useSystemPropertyValues;
+            return this;
+        }
+
+        public void setUseSystemPropertyValues(Boolean useSystemPropertyValues) {
+            useSystemPropertyValues(useSystemPropertyValues);
+        }
+
         @Override
         public ProxyConfiguration build() {
             return new ProxyConfiguration(this);

http-clients/aws-crt-client/src/test/java/software/amazon/awssdk/http/crt/ProxyConfigurationTest.java

@@ -20,19 +20,93 @@
 import java.lang.reflect.Method;
 import java.util.Random;
 import java.util.stream.Stream;
+import org.junit.AfterClass;
+import org.junit.Before;
 import org.junit.Test;
 
 /**
  * Tests for {@link ProxyConfiguration}.
  */
 public class ProxyConfigurationTest {
     private static final Random RNG = new Random();
+    private static final String TEST_HOST = "foo.com";
+    private static final int TEST_PORT = 7777;
+    private static final String TEST_USER = "testuser";
+    private static final String TEST_PASSWORD = "123";
+
+    @Before
+    public void setup() {
+        clearProxyProperties();
+    }
+
+    @AfterClass
+    public static void cleanup() {
+        clearProxyProperties();
+    }
 
     @Test
     public void build_setsAllProperties() {
         verifyAllPropertiesSet(allPropertiesSetConfig());
     }
 
+    @Test
+    public void build_systemPropertyDefault() {
+        setProxyProperties();
+        ProxyConfiguration config = ProxyConfiguration.builder().build();
+
+        assertThat(config.host()).isEqualTo(TEST_HOST);
+        assertThat(config.port()).isEqualTo(TEST_PORT);
+        assertThat(config.username()).isEqualTo(TEST_USER);
+        assertThat(config.password()).isEqualTo(TEST_PASSWORD);
+        assertThat(config.scheme()).isNull();
+    }
+
+    @Test
+    public void build_systemPropertyEnabled() {
+        setProxyProperties();
+        ProxyConfiguration config = ProxyConfiguration.builder().useSystemPropertyValues(Boolean.TRUE).build();
+
+        assertThat(config.host()).isEqualTo(TEST_HOST);
+        assertThat(config.port()).isEqualTo(TEST_PORT);
+        assertThat(config.username()).isEqualTo(TEST_USER);
+        assertThat(config.password()).isEqualTo(TEST_PASSWORD);
+        assertThat(config.scheme()).isNull();
+    }
+
+    @Test
+    public void build_systemPropertyDisabled() {
+        setProxyProperties();
+        ProxyConfiguration config = ProxyConfiguration.builder()
+                                                      .host("localhost")
+                                                      .port(8888)
+                                                      .username("username")
+                                                      .password("password")
+                                                      .useSystemPropertyValues(Boolean.FALSE).build();
+
+        assertThat(config.host()).isEqualTo("localhost");
+        assertThat(config.port()).isEqualTo(8888);
+        assertThat(config.username()).isEqualTo("username");
+        assertThat(config.password()).isEqualTo("password");
+        assertThat(config.scheme()).isNull();
+    }
+
+    @Test
+    public void build_systemPropertyOverride() {
+        setProxyProperties();
+        ProxyConfiguration config = ProxyConfiguration.builder()
+                                                      .host("localhost")
+                                                      .port(8888)
+                                                      .username("username")
+                                                      .password("password")
+                                                      .build();
+
+        assertThat(config.host()).isEqualTo("localhost");
+        assertThat(config.port()).isEqualTo(8888);
+        assertThat(config.username()).isEqualTo("username");
+        assertThat(config.password()).isEqualTo("password");
+        assertThat(config.scheme()).isNull();
+    }
+
     @Test
     public void toBuilder_roundTrip_producesExactCopy() {
         ProxyConfiguration original = allPropertiesSetConfig();
@@ -76,6 +150,8 @@ private void setRandomValue(Object o, Method setter) throws InvocationTargetExce
             setter.invoke(o, randomString());
         } else if (int.class.equals(paramClass)) {
             setter.invoke(o, RNG.nextInt());
+        } else if (Boolean.class.equals(paramClass)) {
+            setter.invoke(o, RNG.nextBoolean());
         } else {
             throw new RuntimeException("Don't know how create random value for type " + paramClass);
         }
@@ -108,4 +184,18 @@ private String randomString() {
 
         return sb.toString();
     }
+
+    private void setProxyProperties() {
+        System.setProperty("http.proxyHost", TEST_HOST);
+        System.setProperty("http.proxyPort", Integer.toString(TEST_PORT));
+        System.setProperty("http.proxyUser", TEST_USER);
+        System.setProperty("http.proxyPassword", TEST_PASSWORD);
+    }
+
+    private static void clearProxyProperties() {
+        System.clearProperty("http.proxyHost");
+        System.clearProperty("http.proxyPort");
+        System.clearProperty("http.proxyUser");
+        System.clearProperty("http.proxyPassword");
+    }
 }