I am trying to replate a pattern (that contains many specials chars) with a simple string that I have in a file called "file". I''m using sed to get it done. The command runs without any exception but the target file remains the same...

I'm trying to replace this:

<%=ENV["SECRET_KEY_BASE"]%>

with this (the content in the file):

88ce3e2c0fa0b667567dc370f8c62019ee88f1628ee1586651d7ea4a0faf18d0dbccaeb3f21c46109d2087ff31f07cf3734ce7a38f64f5a92cdf91dcb3494d1f** ... in a file called **secrets.yml

That's the commands I've tried but doesn't seem to work:

sed -i 's/<%=ENV["SECRET_KEY_BASE"]%>/$(cat file)/g' config/secrets.yml

also tried with variables this way, but nothing changed:

var1="<%=ENV["SECRET_KEY_BASE"]%>" && var2="`cat file`" && sed -i 's/$var1/$var2/g' config/secrets.yml

Does anyone have an idea what i'm missing here?

CodePudding user response：

There are two issues I see with what you have currently:

1. 's/<%=ENV["SECRET_KEY_BASE"]%>/$(cat file)/g' is using single quotes which will prevent interpretation of the command to cat the file
2. You need to escape a few things in the comparison string like: <%=ENV\[\"SECRET_KEY_BASE\"\]%>

Putting those things together, this is working for me:

sed -i "s/<%=ENV\[\"SECRET_KEY_BASE\"\]%>/$(cat file)/g" secrets.yml

CodePudding user response：

Certain special characters must be escaped when using sed. In this case it's the square brackets and the double quotes in the string to be replaced.

sed -i "s|<%=ENV\[\"SECRET_KEY_BASE\"\]%>|88ce3e2c0fa0b667567dc370f8c62019ee88f1628ee1586651d7ea4a0faf18d0dbccaeb3f21c46109d2087ff31f07cf3734ce7a38f64f5a92cdf91dcb3494d1f|g" secrets.yml