encode string with base 64 returns empty or null in shell script

Question

I am trying to prepare url, in which email address will be base64 encoded. However when I encode the email with base64 it returns emptry string, without base64 encode this works fine, what am I missing here?

here is shell script without base64 encode

#!/bin/bash

link='unsubscribe'
testVar="$link/""[email protected]"
echo "www.somedomain.com/$testVar/email/"

Output:

www.somedomain.com/unsubscribe/me@domain/email/

I am trying to encode email with base64 like this:

#!/bin/bash

link='unsubscribe'
testVar="$link/""[email protected]"|base64
echo "www.somedomain.com/$testVar/email/"

Output

www.somedomain.com/unsubscribe//email/

Notice the email did not get encoded, returned empty value

what I am missing here?

Inian · Accepted Answer · 2017-05-15 11:01:16Z

3

You are not passing the string contained in the variable test to base64 command, use Command substitution $(..) syntax to pass the string without newline to the command, using printf

#!/usr/bin/bash

link='unsubscribe'
test=$(printf "%s" "$link/""[email protected]" | base64)
echo "www.somedomain.com/${test}/email/"

produces an output as

www.somedomain.com/dW5zdWJzY3JpYmUvbWVAZG9tYWluLmNvbQ==/email/

Not relevant to your actual question, but I think as a general coding guideline, you should not name variables as test, as this can be easily confused with the test operator in bash. Would be good if you can add more context to what purpose the variable is used for, may be testVar, testStr or testRef.

edited May 15, 2017 at 11:01

answered May 15, 2017 at 10:34

Inian

87k15 gold badges166 silver badges183 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

123 Over a year ago

or just echo "www.somedomain.com/$(base64 <<< "$link/[email protected]")/email/" would be sufficient.

Inian Over a year ago

@123: If am not wrong, here-string, creates a new-line after the string, just like echo, try hexdump -c <<< "Hello World". Compare it with just hexdump -c < <( printf "%s" "Hello World" ). Hence your command might produce a different md5 string including the \n

123 Over a year ago

Whoops, yeah your right, the point of the comment was that you could use command sub directly in the echo.

Rahul Over a year ago

@Inian yes agreed to your comment related to naming variables properly, for asking question purpose I submitted the pseudo code, even then naming should have been proper, agreed :) thanks for your help, made edits in my question

Collectives™ on Stack Overflow

encode string with base 64 returns empty or null in shell script

1 Answer 1

4 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

4 Comments

Your Answer

Sign up or log in

Post as a guest

Related