卷曲下载到HDFS [英] Curl download to HDFS

问题描述

我有以下代码:

curl -o fileName.csv url | xargs hdfs dfs -moveFromLocal $1 /somePath/

当我执行此代码时，curl将来自请求的值放入fileName.csv中，文件将移至HDFS.我想知道是否可以，将curl输出保留在内存中，发送到管道，然后将值写入HDFS?

When i execute this code, curl put the values from request inside fileName.csv, the file are moved to HDFS. I wanna know if i can, mantain the curl output in memory, send to pipe and just write the values inside HDFS?

类似的东西(有效):

curl url | xargs hdfs dfs -put $1 /somePath

推荐答案

hdfs dfs -put命令可以接受stdin的文件输入，使用熟悉的习惯用法指定-表示stdin:

The hdfs dfs -put command can accept file input from stdin, using the familiar idiom of specifying - to mean stdin:

> curl -sS https://www.google.com/robots.txt | hdfs dfs -put - /robots.txt
> hdfs dfs -ls /robots.txt
-rw-r--r--   3 cnauroth supergroup       6880 2017-07-06 09:07 /robots.txt

另一种选择是使用外壳程序进程替换以允许处理curl(或实际上您选择的任何命令)的标准输出，好像它是另一个命令的文件输入一样:

Another option is to use shell process substitution to allow treating the stdout of curl (or really any command you choose) as if it were a file input to another command:

> hdfs dfs -put <(curl -sS https://www.google.com/robots.txt) /robots.txt
> hdfs dfs -ls /robots.txt
-rw-r--r--   3 cnauroth supergroup       6880 2017-07-05 15:07 /robots.txt

这篇关于卷曲下载到HDFS的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！