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+I Need My Report
+================
+
+**Junior**
+
+  Good morning!
+
+  You look very busy, what's the matter?
+
+**Senior**
+
+  I am finishing the capacity planning report.  Let me just
+  mail it... Done!
+
+  Today I am going to teach you how to do this report so we can split
+  the workload.
+
+**Junior**
+
+  Oh. That sounds... fun.  Ok, tell me about this report.
+
+**Senior**
+
+  Here at ACME Inc. we take capacity planning seriously.  It is
+  important that our employees always have the best resources to
+  accomplish their job.
+
+  We prepare a report with some statistics about the load of our
+  servers.  This way we know when we have to buy another one.
+  
+**Junior**
+
+  I see this company scales just like Google.
+
+**Senior**
+
+  We have a procedure:
+
+  1. SSH into the machine.
+  2. Execute the following commands copying its output for later fill in
+     the report:
+
+     - ``hostname`` and ``date``:  To include in the report.
+     - ``free -m``:  To know if we have to buy more RAM.
+     - ``uptime``:  To see the load of the system.
+     - ``df -h``:  Just in case we need another hard disk.
+
+  3. Copy all this in a mail and send it to *Susan*, the operations
+     manager.
+
+**Junior**
+
+  And why *Susan* don't enter the server herself to see all of this?
+
+**Senior**
+
+  She doesn't have time for this. She is a manager, she is very busy!
+
+**Junior**
+
+  Well, I guess we can make a Kapow! endpoint to let her see all this
+  information from the browser.  This way she doesn't need to waste any
+  time asking us.
+
+  I started to write it already:
+
+  .. code-block:: console
+
+     kapow route add /capacityreport -c 'hostname | kapow set /response/body; date | kapow set /response/body; free -m | kapow set /response/body; uptime | kapow set /response/body; df -h | kapow set /response/body'
+
+**Senior**
+
+  That is preposterous!
+
+  First of all that code is not readable.  And the output would be
+  something like.
+
+  .. code-block:: text
+
+     corporate-server
+     Tue 26 Nov 2019 01:03:44 PM CET
+                   total        used        free      shared  buff/cache   available
+     Mem:          31967        2286       23473         729        6207       28505
+     Swap:             0           0           0
+      13:03:44 up  5:57,  1 user,  load average: 0.76, 0.63, 0.45
+     Filesystem          Size  Used Avail Use% Mounted on
+     dev                  16G     0   16G   0% /dev
+     run                  16G  1.7M   16G   1% /run
+
+  Which is also very difficult to read!
+
+  What *Susan* is used to see is more like:
+
+  .. code-block:: text
+
+     Hostname:
+     ... the output of `hostname` ...
+     ================================================================================
+     Date:
+     ... the output of `date` ...
+     ================================================================================
+     Memory:
+     ... the output of `free -m` ...
+     ================================================================================
+     ... and so on ... 
+
+**Junior**
+
+  All right, what about this?
+
+  .. code-block:: console
+
+     kapow route add /capacityreport -c 'hostname | kapow set /response/body; echo ================================================================================ | kapow set /response/body; ...'
+
+**Senior**
+
+  That fix the issue for *Susan* but make it worst for us.
+
+  What about a HEREDOC to help us make the code more readable.
+
+**Junior**
+
+  A *HEREwhat*?
+
+**Senior**
+
+  A HEREDOC or **here document** is the method Unix shells use to
+  express multi-line literals.
+
+  They look like this:
+
+  .. code-block:: console
+
+     $ cat <<HERE
+        you can put
+        more than one line
+        here
+       HERE
+  
+  The shell will put the data between the first ``HERE`` and the second
+  ``HERE`` as the ``stdin`` of the ``cat`` process.
+
+**Junior**
+
+  If I want to use this with Kapow! I have to make it read the script
+  from ``stdin``.  To do this I know that I have to put a ``-`` at the
+  end.
+
+  Let me try:
+
+  .. code-block:: bash
+
+     kapow route add /capacityreport - <<-HERE
+         hostname | kapow set /response/body
+         echo ================================================================================ | kapow set /response/body
+         date | kapow set /response/body
+         echo ================================================================================ | kapow set /response/body
+         free -m | kapow set /response/body
+         echo ================================================================================ | kapow set /response/body
+         uptime | kapow set /response/body
+         echo ================================================================================ | kapow set /response/body
+         df -h | kapow set /response/body
+         echo ================================================================================ | kapow set /response/body
+     HERE
+
+**Senior**
+
+  That would work. Nevertheless I am not satisfied.
+
+  What about all the repeated ``kapow set /response/body`` statements?
+  Could we do any better?
+
+**Junior**
+
+  Maybe we can redirect all to a file and use the file as the input of
+  ``kapow set /response/body``.
+
+**Senior**
+
+  There is a better way. You can make use of another neat ``bash``
+  feature: **group commands**.
+
+  Group commands allows you to execute several commands treating the
+  group as one single command.
+
+  You can use this way:
+
+  .. code-block:: bash
+
+     { command1; command2; } | command3
+
+**Junior**
+
+  What about this:
+
+  .. code-block:: bash
+
+     kapow route add /capacityreport - <<-HERE
+         {
+         hostname
+         echo ================================================================================
+         date
+         echo ================================================================================
+         free -m
+         echo ================================================================================
+         uptime
+         echo ================================================================================
+         df -h
+         echo ================================================================================
+         } | kapow set /response/body
+     HERE
+
+**Senior**
+
+  I am not worried about maintaining that script. Good job!
+
+**Junior**
+
+  You know me. Whatever it takes to avoid writing reports ;)