Question

我有一个docker文件：

FROM rocker/verse:latest
RUN apt-get update 
RUN R -e "install.packages('TraMineR', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('ggthemes', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('ggplot2', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('Rcpp'            , repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('data.table', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('randomForest', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('pROC'            , repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('stringr', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('ggplot2', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('ggthemes', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('TraMineR', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('bipartite', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('tm'            , repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('dummies', repos = 'http://cran.us.r-project.org')"
RUN R -e "install.packages('xgboost', repos = 'http://cran.us.r-project.org')"

RUN R -e "install.packages('SnowballC', repos = 'http://cran.us.r-project.org')"

我构建它，然后运行它并获得一个容器。在此容器中，我运行一个R文件并尝试保存一个对象：

NdelivIDexcessif<-15 ; 
save(NdelivIDexcessif, file="sauvegardeTest.rda")

这不会产生任何输出，因为我期望在当前目录上创建一个“ sauvegardeTest.rda”。

我想念什么？

Answer 1

可能是几种可能的事情之一，（在我看来）头两个是：

Docker在容器停止时默认会破坏环境（例如，对文件系统的更改）。这可以提高安全性和代码清洁度，但它要求容器完成后，如果必须具有文件级持久性，则必须显式设置它。

没有任何内容，找不到文件。

root@myhost:/tmp/ltest# ll
total 76
drwxr-xr-x  2 root root  4096 Sep 26 19:08 ./
drwxrwxrwt 35 root root 69632 Sep 26 19:08 ../


root@myhost:/tmp/ltest# docker run \
  --rm -it rocker/tidyverse:3.3.3 \
  R -e "save(mtcars, file='mt.rda')"

R version 3.3.3 (2017-03-06) -- "Another Canoe"
Copyright (C) 2017 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> save(mtcars, file='mt.rda')
>
>

root@myhost:/tmp/ltest# ll
total 76
drwxr-xr-x  2 root root  4096 Sep 26 19:08 ./
drwxrwxrwt 35 root root 69632 Sep 26 19:08 ../

但是，如果您明确设置卷或挂载点（https://docs.docker.com/storage/volumes/#choose-the--v-or---mount-flag），则可以实现持久性。

root@myhost:/tmp/ltest# docker run \
  -v /tmp/ltest:/tmp/rtest/ \
  --rm -it rocker/tidyverse:3.3.3 \
  R -e "save(mtcars, file='/tmp/rtest/mt.rda')"

R version 3.3.3 (2017-03-06) -- "Another Canoe"
Copyright (C) 2017 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> save(mtcars, file='/tmp/rtest/mt.rda')
>
>

root@franz:/tmp/ltest# ls -l
total 4
-rw-r--r-- 1 root root 1234 Sep 26 19:04 mt.rda

如果您已经通过某种机制安装它，请确保在save命令中设置路径，或者通过预先设置R进程的工作目录来设置路径：

docker run \
  -v /tmp/rtest:/tmp/rtest/ \
  -w /tmp/rtest/ --rm -it \
  rocker/tidyverse:3.3.3 R -e "save(mtcars, file='mt.rda')"
docker run \
  -v /tmp/rtest:/tmp/rtest/ \
  --rm -ti \
  rocker/tidyverse:3.3.3 R -e "save(mtcars, file='/tmp/rtest/mt.rda')"

请注意，目录在容器外部和内部的位置是唯一的；尽管您可以使它们相同，但是并不需要这样做。在此示例中，容器外部的 real 目录为/tmp/ltest/，内部目录的名称为/tmp/rtest/。

Docker + R：为什么“保存”方法不起作用？

1 个答案: