support the new docker build --pull option

doc/changelog.md

@@ -6,6 +6,7 @@
   - Migrate from joda-time to java.time ([#1025](https://github.com/fabric8io/docker-maven-plugin/issues/1025))
     The handling of Y changes when the week straddle the New year ([Stack Overflow](https://stackoverflow.com/questions/26431882/difference-between-year-of-era-and-week-based-year))
   - Fix JSON error when parsin tafs (#1354)
+  - Support to autoPull in build configuration (#626)
   - Add `skipPush` option to build image configuration ([#1243](https://github.com/fabric8io/docker-maven-plugin/issues/1243))
   - docker.container.<alias>.ip property is no longer set ([#1242](https://github.com/fabric8io/docker-maven-plugin/issues/1242))
   - Support `squash` in build options to squash newly built layers into a single layer ([#785](https://github.com/fabric8io/docker-maven-plugin/issues/785)) 

src/main/asciidoc/inc/build/_configuration.adoc

@@ -71,6 +71,9 @@ endif::[]
 
 A provided `<from>` takes precedence over the name given here. This tag is useful for extensions of this plugin like the https://maven.fabric8.io[fabric8-maven-plugin] which can evaluate the additional information given here.
 
+| *autoPull*
+| Whether we need to pull a newer version of image.
+
 | <<build-healthcheck, *healthCheck*>>
 | Definition of a health check as described in <<build-healthcheck, Healthcheck>>
 
@@ -139,6 +142,7 @@ remote API.
 <build>
   <from>java:8u40</from>
   <maintainer>[email protected]</maintainer>
+  <autoPull>true</autoPull>
   <tags>
     <tag>latest</tag>
     <tag>${project.version}</tag>

src/main/java/io/fabric8/maven/docker/BuildMojo.java

@@ -13,6 +13,7 @@
 import io.fabric8.maven.docker.access.DockerAccessException;
 import io.fabric8.maven.docker.config.BuildImageConfiguration;
 import io.fabric8.maven.docker.config.ImageConfiguration;
+import io.fabric8.maven.docker.config.ImagePullPolicy;
 import io.fabric8.maven.docker.service.BuildService;
 import io.fabric8.maven.docker.service.ImagePullManager;
 import io.fabric8.maven.docker.service.ServiceHub;
@@ -74,7 +75,7 @@ protected void buildAndTag(ServiceHub hub, ImageConfiguration imageConfig)
         EnvUtil.storeTimestamp(getBuildTimestampFile(), getBuildTimestamp());
 
         BuildService.BuildContext buildContext = getBuildContext();
-        ImagePullManager pullManager = getImagePullManager(determinePullPolicy(imageConfig.getBuildConfiguration()), autoPull);
+        ImagePullManager pullManager = getImagePullManager(determinePullPolicy(imageConfig.getBuildConfiguration()), determineAutoPull(imageConfig.getBuildConfiguration()));
         BuildService buildService = hub.getBuildService();
 
         File buildArchiveFile = buildService.buildArchive(imageConfig, buildContext, resolveBuildArchiveParameter());
@@ -117,6 +118,10 @@ private String determinePullPolicy(BuildImageConfiguration buildConfig) {
         return buildConfig != null && buildConfig.getImagePullPolicy() != null ? buildConfig.getImagePullPolicy() : imagePullPolicy;
     }
 
+    private String determineAutoPull(BuildImageConfiguration buildConfig) {
+        return buildConfig != null && buildConfig.getAutoPull() != null ? buildConfig.getAutoPull() : autoPull;
+    }
+
     /**
      * Helper method to process an ImageConfiguration.
      *

src/main/java/io/fabric8/maven/docker/access/BuildOptions.java

@@ -27,21 +27,37 @@
  */
 public class BuildOptions {
 
-    private Map<String, String> options;
+    private final Map<String, String> options;
 
     public BuildOptions() {
-        this(new HashMap<String, String>());
+        this(new HashMap<>());
     }
 
     public BuildOptions(Map<String, String> options) {
-        this.options = options != null ? new HashMap<>(options) : new HashMap<String, String>();
+        this.options = options != null ? new HashMap<>(options) : new HashMap<>();
     }
 
     public BuildOptions addOption(String key, String value) {
         options.put(key,value);
         return this;
     }
 
+    public BuildOptions autoPull(String autoPull) {
+        if (autoPull != null) {
+            switch (autoPull.toLowerCase()) {
+                case "always":
+                case "true" :
+                case "ifnotpresent":
+                    options.put("pull", Boolean.TRUE.toString());
+                    break;
+                case "false":
+                case "never":
+                    options.put("pull", Boolean.FALSE.toString());
+            }
+        }
+        return this;
+    }
+
     public BuildOptions dockerfile(String name) {
         if (name != null) {
             options.put("dockerfile", name);

src/main/java/io/fabric8/maven/docker/config/BuildImageConfiguration.java

@@ -18,6 +18,9 @@ public class BuildImageConfiguration implements Serializable {
     public static final String DEFAULT_FILTER = "${*}";
     public static final String DEFAULT_CLEANUP = "try";
 
+    @Parameter
+    private String autoPull;
+
     /**
      * Directory is used as build context.
      * If not specified, dockerfile's parent directory is used as build context.
@@ -185,6 +188,10 @@ public boolean isDockerFileMode() {
         return dockerFileFile != null;
     }
 
+    public String getAutoPull() {
+        return autoPull;
+    }
+
     public String getLoadNamePattern() {
         return loadNamePattern;
     }
@@ -422,6 +429,11 @@ public Builder(BuildImageConfiguration that) {
             }
         }
 
+        public Builder autoPull(String autoPull) {
+            config.autoPull = autoPull;
+            return this;
+        }
+
         public Builder contextDir(String dir) {
             config.contextDir = dir;
             return this;

src/main/java/io/fabric8/maven/docker/service/BuildService.java

@@ -12,6 +12,7 @@
 import java.util.Properties;
 import java.util.regex.PatternSyntaxException;
 
+import io.fabric8.maven.docker.config.ImagePullPolicy;
 import org.apache.maven.plugin.MojoExecutionException;
 import com.google.common.collect.ImmutableMap;
 import com.google.gson.JsonObject;
@@ -172,6 +173,7 @@ protected void buildImage(ImageConfiguration imageConfig, MojoParameters params,
         // auto is now supported by docker, consider switching?
         BuildOptions opts =
                 new BuildOptions(buildConfig.getBuildOptions())
+                        .autoPull(calculateAutoPullFromImagePullPolicy(buildConfig.getImagePullPolicy()))
                         .dockerfile(getDockerfileName(buildConfig))
                         .forceRemove(cleanupMode.isRemove())
                         .noCache(noCache)
@@ -442,6 +444,13 @@ private boolean isEmpty(String str) {
         return str == null || str.isEmpty();
     }
 
+    static String calculateAutoPullFromImagePullPolicy(String imagePullPolicy) {
+        if (imagePullPolicy != null) {
+            return Boolean.toString(!imagePullPolicy.equals(ImagePullPolicy.Never.name()));
+        }
+        return Boolean.FALSE.toString();
+    }
+
 
     // ===========================================
 

src/test/java/io/fabric8/maven/docker/access/BuildConfigTest.java

@@ -24,6 +24,8 @@
 import io.fabric8.maven.docker.util.JsonFactory;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
 
 /**
  * @author roland
@@ -73,6 +75,15 @@ public void dockerfile() {
         assertEquals(0, opts.getOptions().size());
     }
 
+    @Test
+    public void autoPull() {
+        BuildOptions opts = new BuildOptions().autoPull("true");
+        assertEquals("true", opts.getOptions().get("pull"));
+
+        opts = new BuildOptions().autoPull(null);
+        assertFalse(opts.getOptions().containsKey("pull"));
+    }
+
     @Test
     public void buildArgs() {
         Map<String,String> args = Collections.singletonMap("arg1","blub");
@@ -96,23 +107,23 @@ public void override() {
 
     @Test
     public void cacheFrom() {
-        BuildOptions opts = new BuildOptions().cacheFrom(Arrays.asList("foo/bar:latest"));
+        BuildOptions opts = new BuildOptions().cacheFrom(Collections.singletonList("foo/bar:latest"));
         assertEquals("[\"foo/bar:latest\"]", opts.getOptions().get("cachefrom"));
 
         opts.cacheFrom(Arrays.asList("foo/bar:latest", "foo/baz:1.0"));
         assertEquals("[\"foo/bar:latest\",\"foo/baz:1.0\"]", opts.getOptions().get("cachefrom"));
 
-        opts.cacheFrom(Arrays.asList());
-        assertEquals(null, opts.getOptions().get("cachefrom"));
+        opts.cacheFrom(Collections.emptyList());
+        assertNull(opts.getOptions().get("cachefrom"));
 
         opts.cacheFrom(null);
-        assertEquals(null, opts.getOptions().get("cachefrom"));
+        assertNull(opts.getOptions().get("cachefrom"));
     }
 
     @Test
     public void network() {
         BuildOptions opts = new BuildOptions().network(null);
-        assertEquals(null, opts.getOptions().get("networkmode"));
+        assertNull(opts.getOptions().get("networkmode"));
 
         opts.network("host");
         assertEquals("host", opts.getOptions().get("networkmode"));