Nebula Exchange SST 2.x Hands-on Guide

这篇文章带大家以最小方式,快速趟一下 Nebula Exchange 中 SST 写入方式的步骤。

之前我在 Nebula Data Import Options 之中介绍过,Nebula Exchange 是一个 Nebula Graph 社区开源的 Spark Applicaiton,它专门用来支持批量或者流式地把数据导入 Nebula Graph Database 之中。

Nebula Exchange 支持多种多样的数据源(从 Apache Parquet, ORC, JSON, CSV, HBase, Hive MaxCompute 到 Neo4j, MySQL, ClickHouse, 再有 Kafka, Pulsar,更多的数据源也在不断增加之中)。

nebula-exchange-digram

如上图所示,在 Exchange 内部,从除了不同 Reader 可以读取不同数据源之外,在数据经过 Processor 处理之后通过 Writer写入(sink) Nebula Graph 图数据库的时候,除了走正常的 ServerBaseWriter 的写入流程之外,它还可以绕过整个写入流程,利用 Spark 的计算能力并行生成底层 RocksDB 的 SST 文件,从而实现超高性能的数据导入,这个 SST 文件导入的场景就是本文带大家上手熟悉的部分。

详细信息请参阅:Nebula Graph 手册:什么是 Nebula Exchange

Nebula Graph 官方博客也有更多 Nebula Exchange 的实践文章

为了最小化使用 Nebula Exchange 的 SST 功能,我们需要:

  • 搭建一个 Nebula Graph 集群,创建导入数据的 Schema,我们选择使用 Docker-Compose 方式、利用 Nebula-Up 快速部署,并简单修改其网络,以方便同样容器化的 Exchange 程序对其访问。
  • 搭建容器化的 Spark 运行环境
  • 搭建容器化的 HDFS

借助于 Nebula-Up 我们可以在 Linux 环境下一键部署一套 Nebula Graph 集群:

bash

curl -fsSL nebula-up.siwei.io/install.sh | bash

nebula-up

待部署成功之后,我们需要对环境做一些修改,这里我做的修改其实就是两点:

  1. 只保留一个 metaD 服务
  2. 起用 Docker 的外部网络

详细修改的部分参考附录一

应用 docker-compose 的修改:

bash

cd ~/.nebula-up/nebula-docker-compose
vim docker-compose.yaml # 参考附录一
docker network create nebula-net # 需要创建外部网络
docker-compose up -d --remove-orphans

之后,我们来创建要测试的图空间,并创建图的 Schema,为此,我们可以利用 nebula-console ,同样,Nebula-Up 里自带了容器化的 nebula-console。

  • 进入 Nebula-Console 所在的容器

bash

~/.nebula-up/console.sh
/ #
  • 在 console 容器里发起链接到图数据库,其中 192.168.x.y 是我所在的 Linux VM 的第一个网卡地址,请换成您的

text

/ # nebula-console -addr 192.168.x.y -port 9669 -user root -p password
[INFO] connection pool is initialized successfully

Welcome to Nebula Graph!
  • 创建图空间(我们起名字叫 sst ),以及 schema

sql

create space sst(partition_num=5,replica_factor=1,vid_type=fixed_string(32));
:sleep 20
use sst
create tag player(name string, age int);

示例输出

sql

(root@nebula) [(none)]> create space sst(partition_num=5,replica_factor=1,vid_type=fixed_string(32));
Execution succeeded (time spent 1468/1918 us)

(root@nebula) [(none)]> :sleep 20

(root@nebula) [(none)]> use sst
Execution succeeded (time spent 1253/1566 us)

Wed, 18 Aug 2021 08:18:13 UTC

(root@nebula) [sst]> create tag player(name string, age int);
Execution succeeded (time spent 1312/1735 us)

Wed, 18 Aug 2021 08:18:23 UTC

利用 big data europe 做的工作,这个过程非常容易。

值得注意的是:

  • 现在的 Nebula Exchange 对 Spark 的版本有要求,在现在的 2021 年 8 月,我是用了 spark-2.4.5-hadoop-2.7 的版本。
  • 为了方便,我让 Spark 运行在 Nebula Graph 相同的机器上,并且指定了运行在同一个 Docker 网络下

bash

docker run --name spark-master --network nebula-net \
    -h spark-master -e ENABLE_INIT_DAEMON=false -d \
    bde2020/spark-master:2.4.5-hadoop2.7

然后,我们就可以进入到环境中了:

bash

docker exec -it spark-master bash

进到 Spark 容器中之后,可以像这样安装 maven:

bash

export MAVEN_VERSION=3.5.4
export MAVEN_HOME=/usr/lib/mvn
export PATH=$MAVEN_HOME/bin:$PATH

wget http://archive.apache.org/dist/maven/maven-3/$MAVEN_VERSION/binaries/apache-maven-$MAVEN_VERSION-bin.tar.gz && \
  tar -zxvf apache-maven-$MAVEN_VERSION-bin.tar.gz && \
  rm apache-maven-$MAVEN_VERSION-bin.tar.gz && \
  mv apache-maven-$MAVEN_VERSION /usr/lib/mvn

还可以这样在容器里下载 nebula-exchange 的 jar 包:

bash

cd ~
wget https://repo1.maven.org/maven2/com/vesoft/nebula-exchange/2.1.0/nebula-exchange-2.1.0.jar

同样借助 big-data-euroupe 的工作,这非常简单,不过我们要做一点修改,让它的 docker-compose.yml 文件里使用 nebula-net 这个之前创建的 Docker 网络。

详细修改的部分参考附录二

bash

git clone https://github.com/big-data-europe/docker-hadoop.git
cd docker-hadoop
vim docker-compose.yml
docker-compose up -d

这个配置主要填入的信息就是 Nebula Graph 集群本身和将要写入数据的 Space Name,以及数据源相关的配置(这里我们用 csv 作为例子),最后再配置输出(sink)为 sst

  • Nebula Graph
    • GraphD 地址
    • MetaD 地址
    • credential
    • Space Name
  • 数据源
    • source: csv
      • path
      • fields etc.
    • ink: sst

详细的配置参考附录二

注意,这里 metaD 的地址可以这样获取,可以看到 0.0.0.0:49377->9559 表示 49377 是外部的地址。

bash

$ docker ps | grep meta
887740c15750   vesoft/nebula-metad:v2.0.0                               "./bin/nebula-metad …"   6 hours ago    Up 6 hours (healthy)    9560/tcp, 0.0.0.0:49377->9559/tcp, :::49377->9559/tcp, 0.0.0.0:49376->19559/tcp, :::49376->19559/tcp, 0.0.0.0:49375->19560/tcp, :::49375->19560/tcp                  nebula-docker-compose_metad0_1

bash

docker cp exchange-sst.conf spark-master:/root/
docker cp player.csv spark-master:/root/

其中 player.csv 的例子:

csv

1100,Tim Duncan,42
1101,Tony Parker,36
1102,LaMarcus Aldridge,33
1103,Rudy Gay,32
1104,Marco Belinelli,32
1105,Danny Green,31
1106,Kyle Anderson,25
1107,Aron Baynes,32
1108,Boris Diaw,36
1109,Tiago Splitter,34
1110,Cory Joseph,27
1111,David West,38

进入 spark-master 容器,提交执行 exchange 应用。

bash

docker exec -it spark-master bash
cd /root/
/spark/bin/spark-submit --master local \
    --class com.vesoft.nebula.exchange.Exchange nebula-exchange-2.1.0.jar\
    -c exchange-sst.conf

检查执行结果:

spark-submit 输出:

bash

21/08/17 03:37:43 INFO TaskSetManager: Finished task 31.0 in stage 2.0 (TID 33) in 1093 ms on localhost (executor driver) (32/32)
21/08/17 03:37:43 INFO TaskSchedulerImpl: Removed TaskSet 2.0, whose tasks have all completed, from pool
21/08/17 03:37:43 INFO DAGScheduler: ResultStage 2 (foreachPartition at VerticesProcessor.scala:179) finished in 22.336 s
21/08/17 03:37:43 INFO DAGScheduler: Job 1 finished: foreachPartition at VerticesProcessor.scala:179, took 22.500639 s
21/08/17 03:37:43 INFO Exchange$: SST-Import: failure.player: 0
21/08/17 03:37:43 WARN Exchange$: Edge is not defined
21/08/17 03:37:43 INFO SparkUI: Stopped Spark web UI at http://spark-master:4040
21/08/17 03:37:43 INFO MapOutputTrackerMasterEndpoint: MapOutputTrackerMasterEndpoint stopped!

验证 HDFS 上生成的 SST 文件:

bash

docker exec -it namenode /bin/bash

root@2db58903fb53:/# hdfs dfs -ls /sst
Found 10 items
drwxr-xr-x   - root supergroup          0 2021-08-17 03:37 /sst/1
drwxr-xr-x   - root supergroup          0 2021-08-17 03:37 /sst/10
drwxr-xr-x   - root supergroup          0 2021-08-17 03:37 /sst/2
drwxr-xr-x   - root supergroup          0 2021-08-17 03:37 /sst/3
drwxr-xr-x   - root supergroup          0 2021-08-17 03:37 /sst/4
drwxr-xr-x   - root supergroup          0 2021-08-17 03:37 /sst/5
drwxr-xr-x   - root supergroup          0 2021-08-17 03:37 /sst/6
drwxr-xr-x   - root supergroup          0 2021-08-17 03:37 /sst/7
drwxr-xr-x   - root supergroup          0 2021-08-17 03:37 /sst/8
drwxr-xr-x   - root supergroup          0 2021-08-17 03:37 /sst/9

这里的操作实际上都是参考文档:SST 导入,得来。其中就是从 console 之中执行了两步操作:

  • Download
  • Ingest

其中 Download 实际上是触发 Nebula Graph 从服务端发起 HDFS Client 的 download,获取 HDFS 上的 SST 文件,然后放到 storageD 能访问的本地路径下,这里,需要我们在服务端部署 HDFS 的依赖。因为我们是最小实践,我就偷懒手动做了这个 Download 的操作。

这里边手动下载我们就要知道 Nebula Graph 服务端下载的路径,实际上是 /data/storage/nebula/<space_id>/download/,这里的 Space ID 需要手动获取一下:

这个例子里,我们的 Space Name 是 sst,而 Space ID 是 49

sql

(root@nebula) [sst]> DESC space sst
+----+-------+------------------+----------------+---------+------------+--------------------+-------------+-----------+
| ID | Name  | Partition Number | Replica Factor | Charset | Collate    | Vid Type           | Atomic Edge | Group     |
+----+-------+------------------+----------------+---------+------------+--------------------+-------------+-----------+
| 49 | "sst" | 10               | 1              | "utf8"  | "utf8_bin" | "FIXED_STRING(32)" | "false"     | "default" |
+----+-------+------------------+----------------+---------+------------+--------------------+-------------+-----------+

于是,下边的操作就是手动把 SST 文件从 HDFS 之中 get 下来,再拷贝到 storageD 之中。

bash

docker exec -it namenode /bin/bash

$ hdfs dfs -get /sst /sst
exit
docker cp namenode:/sst .
docker exec -it nebula-docker-compose_storaged0_1 mkdir -p /data/storage/nebula/49/download/
docker exec -it nebula-docker-compose_storaged1_1 mkdir -p /data/storage/nebula/49/download/
docker exec -it nebula-docker-compose_storaged2_1 mkdir -p /data/storage/nebula/49/download/
docker cp sst nebula-docker-compose_storaged0_1:/data/storage/nebula/49/download/
docker cp sst nebula-docker-compose_storaged1_1:/data/storage/nebula/49/download/
docker cp sst nebula-docker-compose_storaged2_1:/data/storage/nebula/49/download/
  • 进入 Nebula-Console 所在的容器

bash

~/.nebula-up/console.sh
/ #
  • 在 console 容器里发起链接到图数据库,其中 192.168.x.y 是我所在的 Linux VM 的第一个网卡地址,请换成您的

text

/ # nebula-console -addr 192.168.x.y -port 9669 -user root -p password
[INFO] connection pool is initialized successfully

Welcome to Nebula Graph!
  • 执行 INGEST 开始让 StorageD 读取 SST 文件

bash

(root@nebula) [(none)]> use sst
(root@nebula) [sst]> INGEST;

我们可以用如下方法实时查看 Nebula Graph 服务端的日志

bash

tail -f ~/.nebula-up/nebula-docker-compose/logs/*/*

成功的 INGEST 日志:

bash

I0817 08:03:28.611877   169 EventListner.h:96] Ingest external SST file: column family default, the external file path /data/storage/nebula/49/download/8/8-6.sst, the internal file path /data/storage/nebula/49/data/000023.sst, the properties of the table: # data blocks=1; # entries=1; # deletions=0; # merge operands=0; # range deletions=0; raw key size=48; raw average key size=48.000000; raw value size=40; raw average value size=40.000000; data block size=75; index block size (user-key? 0, delta-value? 0)=66; filter block size=0; (estimated) table size=141; filter policy name=N/A; prefix extractor name=nullptr; column family ID=N/A; column family name=N/A; comparator name=leveldb.BytewiseComparator; merge operator name=nullptr; property collectors names=[]; SST file compression algo=Snappy; SST file compression options=window_bits=-14; level=32767; strategy=0; max_dict_bytes=0; zstd_max_train_bytes=0; enabled=0; ; creation time=0; time stamp of earliest key=0; file creation time=0;
E0817 08:03:28.611912   169 StorageHttpIngestHandler.cpp:63] SSTFile ingest successfully

题图版权:Pietro Jeng

docker-compose.yaml

diff

diff --git a/docker-compose.yaml b/docker-compose.yaml
index 48854de..cfeaedb 100644
--- a/docker-compose.yaml
+++ b/docker-compose.yaml
@@ -6,11 +6,13 @@ services:
       USER: root
       TZ:   "${TZ}"
     command:
-      - --meta_server_addrs=metad0:9559,metad1:9559,metad2:9559
+      - --meta_server_addrs=metad0:9559
       - --local_ip=metad0
       - --ws_ip=metad0
       - --port=9559
       - --ws_http_port=19559
+      - --ws_storage_http_port=19779
       - --data_path=/data/meta
       - --log_dir=/logs
       - --v=0
@@ -34,81 +36,14 @@ services:
     cap_add:
       - SYS_PTRACE

-  metad1:
-    image: vesoft/nebula-metad:v2.0.0
-    environment:
-      USER: root
-      TZ:   "${TZ}"
-    command:
-      - --meta_server_addrs=metad0:9559,metad1:9559,metad2:9559
-      - --local_ip=metad1
-      - --ws_ip=metad1
-      - --port=9559
-      - --ws_http_port=19559
-      - --data_path=/data/meta
-      - --log_dir=/logs
-      - --v=0
-      - --minloglevel=0
-    healthcheck:
-      test: ["CMD", "curl", "-sf", "http://metad1:19559/status"]
-      interval: 30s
-      timeout: 10s
-      retries: 3
-      start_period: 20s
-    ports:
-      - 9559
-      - 19559
-      - 19560
-    volumes:
-      - ./data/meta1:/data/meta
-      - ./logs/meta1:/logs
-    networks:
-      - nebula-net
-    restart: on-failure
-    cap_add:
-      - SYS_PTRACE
-
-  metad2:
-    image: vesoft/nebula-metad:v2.0.0
-    environment:
-      USER: root
-      TZ:   "${TZ}"
-    command:
-      - --meta_server_addrs=metad0:9559,metad1:9559,metad2:9559
-      - --local_ip=metad2
-      - --ws_ip=metad2
-      - --port=9559
-      - --ws_http_port=19559
-      - --data_path=/data/meta
-      - --log_dir=/logs
-      - --v=0
-      - --minloglevel=0
-    healthcheck:
-      test: ["CMD", "curl", "-sf", "http://metad2:19559/status"]
-      interval: 30s
-      timeout: 10s
-      retries: 3
-      start_period: 20s
-    ports:
-      - 9559
-      - 19559
-      - 19560
-    volumes:
-      - ./data/meta2:/data/meta
-      - ./logs/meta2:/logs
-    networks:
-      - nebula-net
-    restart: on-failure
-    cap_add:
-      - SYS_PTRACE
-
   storaged0:
     image: vesoft/nebula-storaged:v2.0.0
     environment:
       USER: root
       TZ:   "${TZ}"
     command:
-      - --meta_server_addrs=metad0:9559,metad1:9559,metad2:9559
+      - --meta_server_addrs=metad0:9559
       - --local_ip=storaged0
       - --ws_ip=storaged0
       - --port=9779
@@ -119,8 +54,8 @@ services:
       - --minloglevel=0
     depends_on:
       - metad0
-      - metad1
-      - metad2
     healthcheck:
       test: ["CMD", "curl", "-sf", "http://storaged0:19779/status"]
       interval: 30s
@@ -146,7 +81,7 @@ services:
       USER: root
       TZ:   "${TZ}"
     command:
-      - --meta_server_addrs=metad0:9559,metad1:9559,metad2:9559
+      - --meta_server_addrs=metad0:9559
       - --local_ip=storaged1
       - --ws_ip=storaged1
       - --port=9779
@@ -157,8 +92,8 @@ services:
       - --minloglevel=0
     depends_on:
       - metad0
-      - metad1
-      - metad2
     healthcheck:
       test: ["CMD", "curl", "-sf", "http://storaged1:19779/status"]
       interval: 30s
@@ -184,7 +119,7 @@ services:
       USER: root
       TZ:   "${TZ}"
     command:
-      - --meta_server_addrs=metad0:9559,metad1:9559,metad2:9559
+      - --meta_server_addrs=metad0:9559
       - --local_ip=storaged2
       - --ws_ip=storaged2
       - --port=9779
@@ -195,8 +130,8 @@ services:
       - --minloglevel=0
     depends_on:
       - metad0
-      - metad1
-      - metad2
     healthcheck:
       test: ["CMD", "curl", "-sf", "http://storaged2:19779/status"]
       interval: 30s
@@ -222,17 +157,19 @@ services:
       USER: root
       TZ:   "${TZ}"
     command:
-      - --meta_server_addrs=metad0:9559,metad1:9559,metad2:9559
+      - --meta_server_addrs=metad0:9559
       - --port=9669
       - --ws_ip=graphd
       - --ws_http_port=19669
+      - --ws_meta_http_port=19559
       - --log_dir=/logs
       - --v=0
       - --minloglevel=0
     depends_on:
       - metad0
-      - metad1
-      - metad2
     healthcheck:
       test: ["CMD", "curl", "-sf", "http://graphd:19669/status"]
       interval: 30s
@@ -257,17 +194,19 @@ services:
       USER: root
       TZ:   "${TZ}"
     command:
-      - --meta_server_addrs=metad0:9559,metad1:9559,metad2:9559
+      - --meta_server_addrs=metad0:9559
       - --port=9669
       - --ws_ip=graphd1
       - --ws_http_port=19669
+      - --ws_meta_http_port=19559
       - --log_dir=/logs
       - --v=0
       - --minloglevel=0
     depends_on:
       - metad0
-      - metad1
-      - metad2
     healthcheck:
       test: ["CMD", "curl", "-sf", "http://graphd1:19669/status"]
       interval: 30s
@@ -292,17 +231,21 @@ services:
       USER: root
       TZ:   "${TZ}"
     command:
-      - --meta_server_addrs=metad0:9559,metad1:9559,metad2:9559
+      - --meta_server_addrs=metad0:9559
       - --port=9669
       - --ws_ip=graphd2
       - --ws_http_port=19669
+      - --ws_meta_http_port=19559
       - --log_dir=/logs
       - --v=0
       - --minloglevel=0
+      - --storage_client_timeout_ms=60000
+      - --local_config=true
     depends_on:
       - metad0
-      - metad1
-      - metad2
     healthcheck:
       test: ["CMD", "curl", "-sf", "http://graphd2:19669/status"]
       interval: 30s
@@ -323,3 +266,4 @@ services:

 networks:
   nebula-net:
+    external: true

https://github.com/big-data-europe/docker-hadoopdocker-compose.yml

diff

diff --git a/docker-compose.yml b/docker-compose.yml
index ed40dc6..66ff1f4 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -14,6 +14,8 @@ services:
       - CLUSTER_NAME=test
     env_file:
       - ./hadoop.env
+    networks:
+      - nebula-net

   datanode:
     image: bde2020/hadoop-datanode:2.0.0-hadoop3.2.1-java8
@@ -25,6 +27,8 @@ services:
       SERVICE_PRECONDITION: "namenode:9870"
     env_file:
       - ./hadoop.env
+    networks:
+      - nebula-net

   resourcemanager:
     image: bde2020/hadoop-resourcemanager:2.0.0-hadoop3.2.1-java8
@@ -34,6 +38,8 @@ services:
       SERVICE_PRECONDITION: "namenode:9000 namenode:9870 datanode:9864"
     env_file:
       - ./hadoop.env
+    networks:
+      - nebula-net

   nodemanager1:
     image: bde2020/hadoop-nodemanager:2.0.0-hadoop3.2.1-java8
@@ -43,6 +49,8 @@ services:
       SERVICE_PRECONDITION: "namenode:9000 namenode:9870 datanode:9864 resourcemanager:8088"
     env_file:
       - ./hadoop.env
+    networks:
+      - nebula-net

   historyserver:
     image: bde2020/hadoop-historyserver:2.0.0-hadoop3.2.1-java8
@@ -54,8 +62,14 @@ services:
       - hadoop_historyserver:/hadoop/yarn/timeline
     env_file:
       - ./hadoop.env
+    networks:
+      - nebula-net

 volumes:
   hadoop_namenode:
   hadoop_datanode:
   hadoop_historyserver:
+
+networks:
+  nebula-net:
+    external: true

nebula-exchange-sst.conf

toml

{
  # Spark relation config
  spark: {
    app: {
      name: Nebula Exchange 2.1
    }

    master:local

    driver: {
      cores: 1
      maxResultSize: 1G
    }

    executor: {
        memory:1G
    }

    cores:{
      max: 16
    }
  }

  # Nebula Graph relation config
  nebula: {
    address:{
      graph:["192.168.8.128:9669"]
      meta:["192.168.8.128:49377"]
    }
    user: root
    pswd: nebula
    space: sst

    # parameters for SST import, not required
    path:{
        local:"/tmp"
        remote:"/sst"
        hdfs.namenode: "hdfs://192.168.8.128:9000"
    }

    # nebula client connection parameters
    connection {
      # socket connect & execute timeout, unit: millisecond
      timeout: 30000
    }

    error: {
      # max number of failures, if the number of failures is bigger than max, then exit the application.
      max: 32
      # failed import job will be recorded in output path
      output: /tmp/errors
    }

    # use google's RateLimiter to limit the requests send to NebulaGraph
    rate: {
      # the stable throughput of RateLimiter
      limit: 1024
      # Acquires a permit from RateLimiter, unit: MILLISECONDS
      # if it can't be obtained within the specified timeout, then give up the request.
      timeout: 1000
    }
  }

  # Processing tags
  # There are tag config examples for different dataSources.
  tags: [

    # HDFS csv
    # Import mode is sst, just change type.sink to client if you want to use client import mode.
    {
      name: player
      type: {
        source: csv
        sink: sst
      }
      path: "file:///root/player.csv"
      # if your csv file has no header, then use _c0,_c1,_c2,.. to indicate fields
      fields: [_c1, _c2]
      nebula.fields: [name, age]
      vertex: {
        field:_c0
      }
      separator: ","
      header: false
      batch: 256
      partition: 32
    }

  ]
}

相关内容