bash - 从Dockerfile调用脚本时如何防止 `#!/bin/bash: not found`错误

Question

我有以下Dockerfile:

FROM debian:stretch-backports

MAINTAINER c33s

ARG DEBIAN_FRONTEND=noninteractive
COPY provision-base.sh /root/provision-base.sh
RUN chmod +x /root/provision-base.sh && /root/provision-base.sh

为什么我在运行时遇到以下错误:

...snip...
/root/provision-base.sh: 1: /root/provision-base.sh: #!/bin/bash: not found
...snip...

文件存在RUN ls /root/provision-base.sh显示它

RUN which bash也显示bash已安装

该脚本开始运行，并在出现

错误后继续

构建成功

dockerhub上的构建日志:https://hub.docker.com/r/c33s/debian/builds/bd6g8cqr2rtys9a2gguehcw/(构建日志的片段也位于pastebin https://pastebin.com/6x1UK53H上)

Answer 1

我现在怀疑问题出在脚本的内部文件格式中。

通过网络浏览器下载时可能发生了。至少这是在Mac OS上通过Chrome下载/debian/provision-base.sh后得到的:

$ file *
provision-base.sh: Bourne-Again shell script text executable, UTF-8 Unicode (with BOM) text
script-with-good-format.sh:   Bourne-Again shell script text executable, ASCII

然后在构建Dockerfile时发生同样的错误。

可以这样删除BOM，这应该可以解决问题:

awk '{if(NR==1)sub(/^\xef\xbb\xbf/,"");print}' provision-base.sh > provision-base.sh