HBase：REST服务器

REST

REST代表状态转移，它于2000年在Roy Fielding的博士论文中引入，他是HTTP规范的主要作者之一。

REST本身超出了本文档的范围，但通常，REST允许通过与URL本身绑定的API进行客户端-服务器交互。本节讨论如何配置和运行HBase附带的REST服务器，该服务器将HBase表，行，单元和元数据作为URL指定的资源公开。

启动和停止REST服务器

包含的REST服务器可以作为守护程序运行，该守护程序启动嵌入式Jetty servlet容器并将servlet部署到其中。使用以下命令之一在前台或后台启动REST服务器。端口是可选的，默认为8080。

# Foreground
$ bin/hbase rest start -p <port>

# Background, logging to a file in $HBASE_LOGS_DIR
$ bin/hbase-daemon.sh start rest -p <port>

要停止REST服务器，请在前台运行时使用Ctrl-C，如果在后台运行则使用以下命令。

$ bin/hbase-daemon.sh stop rest

配置REST服务器和客户端

有关为SSL配置REST服务器和客户端以及为REST服务器配置doAs模拟的信息，请参阅配置Thrift网关以代表客户端进行身份验证以及Securing Apache HBase章节的其他部分。

使用REST端点

以下示例使用占位符服务器http://example.com:8000，并且可以使用curl或wget命令运行以下命令。您可以通过不为纯文本添加头信息来请求纯文本(默认)，XML或JSON输出，或者为XML添加头信息“Accept：text / xml”，为JSON添加“Accept：application / json”或为协议缓冲区添加“Accept: application/x-protobuf”。

除非指定，否则使用GET请求进行查询，PUT或POST请求进行创建或修改，DELETE用于删除。

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/version/cluster"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/status/cluster"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/namespaces/"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/namespaces/special_ns"

curl -vi -X POST \
  -H "Accept: text/xml" \
  "example.com:8000/namespaces/special_ns"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/namespaces/special_ns/tables"

curl -vi -X PUT \
  -H "Accept: text/xml" \
  "http://example.com:8000/namespaces/special_ns

curl -vi -X DELETE \
  -H "Accept: text/xml" \
  "example.com:8000/namespaces/special_ns"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/users/schema"

curl -vi -X POST \
  -H "Accept: text/xml" \
  -H "Content-Type: text/xml" \
  -d '<?xml version="1.0" encoding="UTF-8"?><TableSchema name="users"><ColumnSchema name="cf" KEEP_DELETED_CELLS="true" /></TableSchema>' \
  "http://example.com:8000/users/schema"

curl -vi -X PUT \
  -H "Accept: text/xml" \
  -H "Content-Type: text/xml" \
  -d '<?xml version="1.0" encoding="UTF-8"?><TableSchema name="users"><ColumnSchema name="cf" /></TableSchema>' \
  "http://example.com:8000/users/schema"

curl -vi -X DELETE \
  -H "Accept: text/xml" \
  "http://example.com:8000/users/schema"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/users/regions

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/users/row1"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/users/row1/cf:a/1458586888395"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/users/row1/cf:a"

curl -vi -X GET \
  -H "Accept: text/xml" \
   "http://example.com:8000/users/row1/cf:a/"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/users/row1/cf:a?v=2"

curl -vi -X PUT \
  -H "Accept: text/xml" \
  -H "Content-Type: text/xml" \
  -d '<Scanner batch="1"/>' \
  "http://example.com:8000/users/scanner/"

curl -vi -X PUT \
  -H "Accept: text/xml" \
  -H "Content-Type:text/xml" \
  -d @filter.txt \
  "http://example.com:8000/users/scanner/"

curl -vi -X GET \
  -H "Accept: text/xml" \
  "http://example.com:8000/users/scanner/145869072824375522207"

curl -vi -X DELETE \
  -H "Accept: text/xml" \
  "http://example.com:8000/users/scanner/145869072824375522207"

curl -vi -X PUT \
  -H "Accept: text/xml" \
  -H "Content-Type: text/xml" \
  -d '<?xml version="1.0" encoding="UTF-8" standalone="yes"?><CellSet><Row key="cm93NQo="><Cell column="Y2Y6ZQo=">dmFsdWU1Cg==</Cell></Row></CellSet>' \
  "http://example.com:8000/users/fakerow"

curl -vi -X PUT \
  -H "Accept: text/json" \
  -H "Content-Type: text/json" \
  -d '{"Row":[{"key":"cm93NQo=", "Cell": [{"column":"Y2Y6ZQo=", "$":"dmFsdWU1Cg=="}]}]}'' \
  "example.com:8000/users/fakerow"

REST XML架构

<schema xmlns="http://www.w3.org/2001/XMLSchema" xmlns:tns="RESTSchema">

  <element name="Version" type="tns:Version"></element>

  <complexType name="Version">
    <attribute name="REST" type="string"></attribute>
    <attribute name="JVM" type="string"></attribute>
    <attribute name="OS" type="string"></attribute>
    <attribute name="Server" type="string"></attribute>
    <attribute name="Jersey" type="string"></attribute>
  </complexType>

  <element name="TableList" type="tns:TableList"></element>

  <complexType name="TableList">
    <sequence>
      <element name="table" type="tns:Table" maxOccurs="unbounded" minOccurs="1"></element>
    </sequence>
  </complexType>

  <complexType name="Table">
    <sequence>
      <element name="name" type="string"></element>
    </sequence>
  </complexType>

  <element name="TableInfo" type="tns:TableInfo"></element>

  <complexType name="TableInfo">
    <sequence>
      <element name="region" type="tns:TableRegion" maxOccurs="unbounded" minOccurs="1"></element>
    </sequence>
    <attribute name="name" type="string"></attribute>
  </complexType>

  <complexType name="TableRegion">
    <attribute name="name" type="string"></attribute>
    <attribute name="id" type="int"></attribute>
    <attribute name="startKey" type="base64Binary"></attribute>
    <attribute name="endKey" type="base64Binary"></attribute>
    <attribute name="location" type="string"></attribute>
  </complexType>

  <element name="TableSchema" type="tns:TableSchema"></element>

  <complexType name="TableSchema">
    <sequence>
      <element name="column" type="tns:ColumnSchema" maxOccurs="unbounded" minOccurs="1"></element>
    </sequence>
    <attribute name="name" type="string"></attribute>
    <anyAttribute></anyAttribute>
  </complexType>

  <complexType name="ColumnSchema">
    <attribute name="name" type="string"></attribute>
    <anyAttribute></anyAttribute>
  </complexType>

  <element name="CellSet" type="tns:CellSet"></element>

  <complexType name="CellSet">
    <sequence>
      <element name="row" type="tns:Row" maxOccurs="unbounded" minOccurs="1"></element>
    </sequence>
  </complexType>

  <element name="Row" type="tns:Row"></element>

  <complexType name="Row">
    <sequence>
      <element name="key" type="base64Binary"></element>
      <element name="cell" type="tns:Cell" maxOccurs="unbounded" minOccurs="1"></element>
    </sequence>
  </complexType>

  <element name="Cell" type="tns:Cell"></element>

  <complexType name="Cell">
    <sequence>
      <element name="value" maxOccurs="1" minOccurs="1">
        <simpleType><restriction base="base64Binary">
        </simpleType>
      </element>
    </sequence>
    <attribute name="column" type="base64Binary" />
    <attribute name="timestamp" type="int" />
  </complexType>

  <element name="Scanner" type="tns:Scanner"></element>

  <complexType name="Scanner">
    <sequence>
      <element name="column" type="base64Binary" minOccurs="0" maxOccurs="unbounded"></element>
    </sequence>
    <sequence>
      <element name="filter" type="string" minOccurs="0" maxOccurs="1"></element>
    </sequence>
    <attribute name="startRow" type="base64Binary"></attribute>
    <attribute name="endRow" type="base64Binary"></attribute>
    <attribute name="batch" type="int"></attribute>
    <attribute name="startTime" type="int"></attribute>
    <attribute name="endTime" type="int"></attribute>
  </complexType>

  <element name="StorageClusterVersion" type="tns:StorageClusterVersion" />

  <complexType name="StorageClusterVersion">
    <attribute name="version" type="string"></attribute>
  </complexType>

  <element name="StorageClusterStatus"
    type="tns:StorageClusterStatus">
  </element>

  <complexType name="StorageClusterStatus">
    <sequence>
      <element name="liveNode" type="tns:Node"
        maxOccurs="unbounded" minOccurs="0">
      </element>
      <element name="deadNode" type="string" maxOccurs="unbounded"
        minOccurs="0">
      </element>
    </sequence>
    <attribute name="regions" type="int"></attribute>
    <attribute name="requests" type="int"></attribute>
    <attribute name="averageLoad" type="float"></attribute>
  </complexType>

  <complexType name="Node">
    <sequence>
      <element name="region" type="tns:Region"
   maxOccurs="unbounded" minOccurs="0">
      </element>
    </sequence>
    <attribute name="name" type="string"></attribute>
    <attribute name="startCode" type="int"></attribute>
    <attribute name="requests" type="int"></attribute>
    <attribute name="heapSizeMB" type="int"></attribute>
    <attribute name="maxHeapSizeMB" type="int"></attribute>
  </complexType>

  <complexType name="Region">
    <attribute name="name" type="base64Binary"></attribute>
    <attribute name="stores" type="int"></attribute>
    <attribute name="storefiles" type="int"></attribute>
    <attribute name="storefileSizeMB" type="int"></attribute>
    <attribute name="memstoreSizeMB" type="int"></attribute>
    <attribute name="storefileIndexSizeMB" type="int"></attribute>
  </complexType>

</schema>

REST Protobufs架构

message Version {
  optional string restVersion = 1;
  optional string jvmVersion = 2;
  optional string osVersion = 3;
  optional string serverVersion = 4;
  optional string jerseyVersion = 5;
}

message StorageClusterStatus {
  message Region {
    required bytes name = 1;
    optional int32 stores = 2;
    optional int32 storefiles = 3;
    optional int32 storefileSizeMB = 4;
    optional int32 memstoreSizeMB = 5;
    optional int32 storefileIndexSizeMB = 6;
  }
  message Node {
    required string name = 1;    // name:port
    optional int64 startCode = 2;
    optional int32 requests = 3;
    optional int32 heapSizeMB = 4;
    optional int32 maxHeapSizeMB = 5;
    repeated Region regions = 6;
  }
  // node status
  repeated Node liveNodes = 1;
  repeated string deadNodes = 2;
  // summary statistics
  optional int32 regions = 3;
  optional int32 requests = 4;
  optional double averageLoad = 5;
}

message TableList {
  repeated string name = 1;
}

message TableInfo {
  required string name = 1;
  message Region {
    required string name = 1;
    optional bytes startKey = 2;
    optional bytes endKey = 3;
    optional int64 id = 4;
    optional string location = 5;
  }
  repeated Region regions = 2;
}

message TableSchema {
  optional string name = 1;
  message Attribute {
    required string name = 1;
    required string value = 2;
  }
  repeated Attribute attrs = 2;
  repeated ColumnSchema columns = 3;
  // optional helpful encodings of commonly used attributes
  optional bool inMemory = 4;
  optional bool readOnly = 5;
}

message ColumnSchema {
  optional string name = 1;
  message Attribute {
    required string name = 1;
    required string value = 2;
  }
  repeated Attribute attrs = 2;
  // optional helpful encodings of commonly used attributes
  optional int32 ttl = 3;
  optional int32 maxVersions = 4;
  optional string compression = 5;
}

message Cell {
  optional bytes row = 1;       // unused if Cell is in a CellSet
  optional bytes column = 2;
  optional int64 timestamp = 3;
  optional bytes data = 4;
}

message CellSet {
  message Row {
    required bytes key = 1;
    repeated Cell values = 2;
  }
  repeated Row rows = 1;
}

message Scanner {
  optional bytes startRow = 1;
  optional bytes endRow = 2;
  repeated bytes columns = 3;
  optional int32 batch = 4;
  optional int64 startTime = 5;
  optional int64 endTime = 6;
}