AdminClient: add getServerInfo API

adminapi/src/main/java/io/minio/admin/MinioAdminClient.java

@@ -31,6 +31,7 @@
 import io.minio.Signer;
 import io.minio.Time;
 import io.minio.admin.messages.DataUsageInfo;
+import io.minio.admin.messages.InfoMessage;
 import io.minio.credentials.Credentials;
 import io.minio.credentials.Provider;
 import io.minio.credentials.StaticProvider;
@@ -79,7 +80,8 @@ private enum Command {
     DATA_USAGE_INFO("datausageinfo"),
     ADD_UPDATE_REMOVE_GROUP("update-group-members"),
     GROUP_INFO("group"),
-    LIST_GROUPS("groups");
+    LIST_GROUPS("groups"),
+    INFO("info");
     private final String value;
 
     private Command(String value) {
@@ -597,6 +599,21 @@ public DataUsageInfo getDataUsageInfo()
     }
   }
 
+  /**
+   * Obtains admin info for the Minio server.
+   *
+   * @return admin info for the Minio server.
+   * @throws NoSuchAlgorithmException thrown to indicate missing of MD5 or SHA-256 digest library.
+   * @throws InvalidKeyException thrown to indicate missing of HMAC SHA-256 library.
+   * @throws IOException thrown to indicate I/O error on MinIO REST operation.
+   */
+  public InfoMessage getServerInfo()
+      throws IOException, NoSuchAlgorithmException, InvalidKeyException {
+    try (Response response = execute(Method.GET, Command.INFO, null, null)) {
+      return OBJECT_MAPPER.readValue(response.body().charStream(), InfoMessage.class);
+    }
+  }
+
   /**
    * Sets HTTP connect, write and read timeouts. A value of 0 means no timeout, otherwise values
    * must be between 1 and Integer.MAX_VALUE when converted to milliseconds.

adminapi/src/main/java/io/minio/admin/clusterinfo/Backend.java

@@ -0,0 +1,83 @@
+/*
+ * MinIO Java SDK for Amazon S3 Compatible Cloud Storage,
+ * (C) 2022 MinIO, Inc.
+ *
+ * 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.minio.admin.clusterinfo;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import java.util.Collections;
+import java.util.LinkedList;
+import java.util.List;
+
+/**
+ * ErasureBackend contains specific erasure storage information
+ *
+ * @see <a href=
+ *     "https://github.com/minio/madmin-go/blob/main/info-commands.go#L359">info-commands.go</a>
+ */
+@JsonIgnoreProperties(ignoreUnknown = true)
+public class Backend {
+  @JsonProperty("backendType")
+  private String backendType;
+
+  @JsonProperty("onlineDisks")
+  private Integer onlineDisks;
+
+  @JsonProperty("offlineDisks")
+  private Integer offlineDisks;
+
+  @JsonProperty("standardSCParity")
+  private Integer standardSCParity;
+
+  @JsonProperty("rrSCParity")
+  private Integer rrSCParity;
+
+  @JsonProperty("totalSets")
+  private List<Integer> totalSets;
+
+  @JsonProperty("totalDrivesPerSet")
+  private List<Integer> totalDrivesPerSet;
+
+  public String backendType() {
+    return backendType;
+  }
+
+  public Integer onlineDisks() {
+    return onlineDisks;
+  }
+
+  public Integer offlineDisks() {
+    return offlineDisks;
+  }
+
+  public Integer standardSCParity() {
+    return standardSCParity;
+  }
+
+  public Integer rrSCParity() {
+    return rrSCParity;
+  }
+
+  public List<Integer> totalSets() {
+    return Collections.unmodifiableList(totalSets == null ? new LinkedList<>() : totalSets);
+  }
+
+  public List<Integer> totalDrivesPerSet() {
+    return Collections.unmodifiableList(
+        totalDrivesPerSet == null ? new LinkedList<>() : totalDrivesPerSet);
+  }
+}

adminapi/src/main/java/io/minio/admin/clusterinfo/Buckets.java

@@ -0,0 +1,44 @@
+/*
+ * MinIO Java SDK for Amazon S3 Compatible Cloud Storage,
+ * (C) 2022 MinIO, Inc.
+ *
+ * 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.minio.admin.clusterinfo;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+/**
+ * Buckets contains the number of buckets
+ *
+ * @see <a href=
+ *     "https://github.com/minio/madmin-go/blob/main/info-commands.go#L286">info-commands.go</a>
+ */
+@JsonIgnoreProperties(ignoreUnknown = true)
+public class Buckets {
+  @JsonProperty("count")
+  private Integer count;
+
+  @JsonProperty("error")
+  private String error;
+
+  public Integer count() {
+    return count;
+  }
+
+  public String error() {
+    return error;
+  }
+}

adminapi/src/main/java/io/minio/admin/clusterinfo/Disk.java

@@ -0,0 +1,206 @@
+/*
+ * MinIO Java SDK for Amazon S3 Compatible Cloud Storage,
+ * (C) 2022 MinIO, Inc.
+ *
+ * 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.minio.admin.clusterinfo;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import java.math.BigDecimal;
+
+/**
+ * Disk holds Disk information
+ *
+ * @see <a href=
+ *     "https://github.com/minio/madmin-go/blob/main/info-commands.go#L404">info-commands.go</a>
+ */
+@JsonIgnoreProperties(ignoreUnknown = true)
+public class Disk {
+  @JsonProperty("endpoint")
+  private String endpoint;
+
+  @JsonProperty("rootDisk")
+  private boolean rootDisk;
+
+  @JsonProperty("path")
+  private String path;
+
+  @JsonProperty("healing")
+  private boolean healing;
+
+  @JsonProperty("scanning")
+  private boolean scanning;
+
+  @JsonProperty("state")
+  private String state;
+
+  @JsonProperty("uuid")
+  private String uuid;
+
+  @JsonProperty("major")
+  private BigDecimal major;
+
+  @JsonProperty("minor")
+  private BigDecimal minor;
+
+  @JsonProperty("model")
+  private String model;
+
+  @JsonProperty("totalspace")
+  private BigDecimal totalspace;
+
+  @JsonProperty("usedspace")
+  private BigDecimal usedspace;
+
+  @JsonProperty("availspace")
+  private BigDecimal availspace;
+
+  @JsonProperty("readthroughput")
+  private BigDecimal readthroughput;
+
+  @JsonProperty("writethroughput")
+  private BigDecimal writethroughput;
+
+  @JsonProperty("readlatency")
+  private BigDecimal readlatency;
+
+  @JsonProperty("writelatency")
+  private BigDecimal writelatency;
+
+  @JsonProperty("utilization")
+  private BigDecimal utilization;
+
+  @JsonProperty("metrics")
+  private DiskMetrics metrics;
+
+  @JsonProperty("heal_info")
+  private HealingDisk healInfo;
+
+  @JsonProperty("used_inodes")
+  private BigDecimal usedInodes;
+
+  @JsonProperty("free_inodes")
+  private BigDecimal freeInodes;
+
+  @JsonProperty("pool_index")
+  private Integer poolIndex;
+
+  @JsonProperty("set_index")
+  private Integer setIndex;
+
+  @JsonProperty("disk_index")
+  private Integer diskIndex;
+
+  public String endpoint() {
+    return endpoint;
+  }
+
+  public boolean isRootDisk() {
+    return rootDisk;
+  }
+
+  public String path() {
+    return path;
+  }
+
+  public boolean isHealing() {
+    return healing;
+  }
+
+  public boolean isScanning() {
+    return scanning;
+  }
+
+  public String state() {
+    return state;
+  }
+
+  public String uuid() {
+    return uuid;
+  }
+
+  public BigDecimal major() {
+    return major;
+  }
+
+  public BigDecimal minor() {
+    return minor;
+  }
+
+  public String model() {
+    return model;
+  }
+
+  public BigDecimal totalspace() {
+    return totalspace;
+  }
+
+  public BigDecimal usedspace() {
+    return usedspace;
+  }
+
+  public BigDecimal availspace() {
+    return availspace;
+  }
+
+  public BigDecimal readthroughput() {
+    return readthroughput;
+  }
+
+  public BigDecimal writethroughput() {
+    return writethroughput;
+  }
+
+  public BigDecimal readlatency() {
+    return readlatency;
+  }
+
+  public BigDecimal writelatency() {
+    return writelatency;
+  }
+
+  public BigDecimal utilization() {
+    return utilization;
+  }
+
+  public DiskMetrics metrics() {
+    return metrics;
+  }
+
+  public HealingDisk healInfo() {
+    return healInfo;
+  }
+
+  public BigDecimal usedInodes() {
+    return usedInodes;
+  }
+
+  public BigDecimal freeInodes() {
+    return freeInodes;
+  }
+
+  public Integer poolIndex() {
+    return poolIndex;
+  }
+
+  public Integer setIndex() {
+    return setIndex;
+  }
+
+  public Integer diskIndex() {
+    return diskIndex;
+  }
+}