Implemente Device parser

KostyaSha · KostyaSha · commit a3880edd5156 · 2016-06-07T22:35:35.000+03:00
Signed-off-by: Kanstantsin Shautsou &lt;kanstantsin.sha@gmail.com&gt;
diff --git a/src/main/java/com/github/dockerjava/api/model/Device.java b/src/main/java/com/github/dockerjava/api/model/Device.java
@@ -1,6 +1,8 @@
 package com.github.dockerjava.api.model;
 
 import static com.google.common.base.Preconditions.checkNotNull;
+import static org.apache.commons.lang.BooleanUtils.isNotTrue;
+import static org.apache.commons.lang.StringUtils.isEmpty;
 
 import org.apache.commons.lang.builder.EqualsBuilder;
 import org.apache.commons.lang.builder.HashCodeBuilder;
@@ -9,6 +11,10 @@
 import com.fasterxml.jackson.annotation.JsonInclude.Include;
 import com.fasterxml.jackson.annotation.JsonProperty;
 
+import javax.annotation.Nonnull;
+import java.util.HashMap;
+import java.util.Map;
+
 @JsonInclude(Include.NON_NULL)
 public class Device {
 
@@ -45,6 +51,66 @@ public String getPathOnHost() {
         return pathOnHost;
     }
 
+    @Nonnull
+    public static Device parse(@Nonnull String deviceStr) {
+        String src = "";
+        String dst = "";
+        String permissions = "rwm";
+        final String[] arr = deviceStr.split(":");
+        switch (arr.length) {
+            case 3: {
+                permissions = arr[2];
+            }
+            case 2: {
+                if (validDeviceMode(arr[1])) {
+                    permissions = arr[1];
+                } else {
+                    dst = arr[1];
+                }
+            }
+            case 1: {
+                src = arr[0];
+                break;
+            }
+            default: {
+                throw new IllegalArgumentException("invalid device specification: " + deviceStr);
+            }
+        }
+
+        if (isEmpty(dst)) {
+            dst = src;
+        }
+
+        return new Device(permissions, dst, src);
+    }
+
+    /**
+     * ValidDeviceMode checks if the mode for device is valid or not.
+     * Valid mode is a composition of r (read), w (write), and m (mknod).
+     *
+     * @link https://github.com/docker/docker/blob/6b4a46f28266031ce1a1315f17fb69113a06efe1/runconfig/opts/parse.go#L796
+     */
+    private static boolean validDeviceMode(String deviceMode) {
+        Map<String, Boolean> validModes = new HashMap<>(3);
+        validModes.put("r", true);
+        validModes.put("w", true);
+        validModes.put("m", true);
+
+        if (isEmpty(deviceMode)) {
+            return false;
+        }
+
+        for (char ch : deviceMode.toCharArray()) {
+            final String mode = String.valueOf(ch);
+            if (isNotTrue(validModes.get(mode))) {
+                return false; // wrong mode
+            }
+            validModes.put(mode, false);
+        }
+
+        return true;
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (obj instanceof Device) {
diff --git a/src/test/java/com/github/dockerjava/api/model/DeviceTest.java b/src/test/java/com/github/dockerjava/api/model/DeviceTest.java
@@ -0,0 +1,27 @@
+package com.github.dockerjava.api.model;
+
+import org.testng.annotations.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+
+/**
+ * @author Kanstantsin Shautsou
+ */
+public class DeviceTest {
+    @Test
+    public void testParse() throws Exception {
+        assertThat(Device.parse("/dev/sda:/dev/xvdc:r"),
+                equalTo(new Device("r", "/dev/xvdc", "/dev/sda")));
+
+        assertThat(Device.parse("/dev/snd:rw"),
+                equalTo(new Device("rw", "/dev/snd", "/dev/snd")));
+
+        assertThat(Device.parse("/dev/snd:/something"),
+                equalTo(new Device("rwm", "/something", "/dev/snd")));
+
+        assertThat(Device.parse("/dev/snd:/something:rw"),
+                equalTo(new Device("rw", "/something", "/dev/snd")));
+
+    }
+}
