spark streaming调用http get存储数据

环境:spark 1.6, 存储是一个http get的服务

在build.sbt中添加”org.apache.httpcomponents” % “httpclient” % “4.5.2”  ,记得第一个分隔符是%,而不是%%。

经过多次尝试,最终代码如下:

agg_wd_business.foreach(d => {
val httpParams = new BasicHttpParams()

HttpConnectionParams.setConnectionTimeout(httpParams, 50)
HttpConnectionParams.setSoTimeout(httpParams, 50)
val client = new DefaultHttpClient(httpParams)
val request = new HttpGet(“http://xxx.xxx.xxx.xxx:9010/rt?” + URLEncoder.encode(d, “UTF-8”))
request.addHeader(“Connection”, “close”)
try{
val response = client.execute(request)
val handler = new BasicResponseHandler()
handler.handleResponse(response).trim.toString
}catch{
case ex: SocketTimeoutException => None
case ex: Exception => None
}
})

发送一个http get请求,设置超时,设置为短连接,并不保证请求一定成功。由于生成的数据有30万左右,得调用http get这么次,而nginx搭配的服务并不能快速地响应。

好记忆不如烂笔头

之前解决问题的时候忘了做笔记,后来遇到相同的问题的时候,不记得之前有个解决方案。年纪大了好多东西都得记得做,有时候忘了这忘了呢,以后做这种技术的话最好还是自己做一下笔记,用wordpress

ScalaPB生成scala的protobuf文件

环境: sbt, scala 2.10.4

 

1.

vi project/scalapb.sbt

addSbtPlugin(“com.thesamet” % “sbt-protoc” % “0.99.1”)

libraryDependencies += “com.trueaccord.scalapb” %% “compilerplugin” % “0.5.43”

 

2.

vi build.sbt

PB.targets in Compile := Seq(
scalapb.gen() -> (sourceManaged in Compile).value
)

// If you need scalapb/scalapb.proto or anything from google/protobuf/*.proto
//ScalaPB looks for protocol buffer files in src/main/protobuf, but this can be customized. Running the compile command in sbt will both generate Scala sources from your protos and compile them.

libraryDependencies += “com.trueaccord.scalapb” %% “scalapb-runtime” % com.trueaccord.scalapb.compiler.Version.scalapbVersion % “protobuf”

 

3.
mkdir src/main/protobuf

vi src/main/protobuf/hello.proto

syntax = “proto3”;
package example;

message HelloRequest {
string name = 1;
}

sbt assembly
生成的scala文件放在 target/scala-2.10/src_managed/main/example/hello/HelloRequest.scala

4.

使用如下
import hello._

val h = HelloRequest().withName(“hq”)
val hba = h.toByteArray
println(hba) //serialize
println(HelloRequest.parseFrom(hba).name) //unserialize

spark streaming读取kafka上的protobuf格式的数据

1. 通过proto文件生成java文件夹

vi test1.proto

syntax = “proto2”;
package example;

message Hello{
required string name = 1;
required int32 id = 2;
}

生成Test1.java
protoc –java_out=pbdir test1.proto

 

2. 将Test1.java拷贝到src/main/java/example目录下

 

3. 通过spark streaming读取kafka上的pb数据
import Test1._

createKafkaStream(ssc, pb_topic, kafkaParams1).map(r => r._2).map(r => {val p = Hello.parseFrom(r.getBytes); p.getId + “\\t” + p.getName})

sbt.ResolveException: unresolved dependency: org.apache.httpcomponents#httpclient_2.10;4.5.2: not found

在build.sbt中添加”org.apache.httpcomponents” %% “httpclient” % “4.5.2”

编译的时候出现报错:

sbt.ResolveException: unresolved dependency: org.apache.httpcomponents#httpclient_2.10;4.5.2: not found

[error] (*:update) sbt.ResolveException: unresolved dependency: org.apache.httpcomponents#httpclient_2.10;4.5.2: not found

 

在stackoverflow找到一个解决方法

Change the first %% to a single %. The double character version is for fetching cross-built libraries, and yours isn’t.

去掉一个%,修改如下:

“org.apache.httpcomponents” % “httpclient” % “4.5.2”