Prerequisites

Read the tutorial [Tutorial for Running Examples][Examples and Tutorials#Tutorial for Running Examples]
Ensure you have read and understand the section on [how to make an example stand alone][Examples and Tutorials#Make the Example Stand Alone]
Ensure you have read the note at the end of that section regarding modification of the body common control to the following:

```cf3 body common control {

inputs => {
   "libraries/cfengine_stdlib.cf",
}; } ```

Note: This change is not necessary for supporting each of the examples in this tutorial. It will be included only in those examples that require it.

List Files

Note: The following workflow assumes the directory /home/user already exists. If it does not either create the directory or adjust the example to a path of your choosing.

Create a file /var/cfengine/masterfiles/file_test.cf that includes the following text:

```cf3

bundle agent list_file {

vars: “ls” slist => lsdir(“/home/user”,”test_plain.txt”,”true”);

reports: “ls: $(ls)”;

} ```
Run the following command to remove any existing test file at the location we wish to use for testing this example:

console rm /home/user/test_plain.txt
Test to ensure there is no file /home/user/test_plain.txt, using the following command (the expected result is that there should be no file listed at the location /home/user/test_plain.txt):

console ls /home/user/test_plain.txt
Run the following command to instruct CFEngine to see if the file exists (the expected result is that no report will be generated (because the file does not exist):

console /var/cfengine/bin/cf-agent --no-lock --file /var/cfengine/masterfiles/file_test.cf --bundlesequence list_file
Create a file for testing the example, using the following command:

console touch /home/user/test_plain.txt
Run the following command to instruct CFEngine to search for the file (the expected result is that a report will be generated, because the file exists):

console /var/cfengine/bin/cf-agent --no-lock --file /var/cfengine/masterfiles/file_test.cf --bundlesequence list_file
Double check the file exists, using the following command (the expected result is that there will be a file listed at the location /home/user/test_plain.txt):

console ls /home/user/test_plain.txt
Run the following command to remove the file:

console rm /home/user/test_plain.txt

Create a File

```cf3

bundle agent testbundle {

files: “/home/user/test_plain.txt” perms => system, create => “true”; }

bundle agent list_file {

vars: “ls” slist => lsdir(“/home/user”,”test_plain.txt”,”true”);

reports: “ls: $(ls)”;

}

bundle agent list_file_2 {

vars: “ls” slist => lsdir(“/home/user”,”test_plain.txt”,”true”);

reports: “ls: $(ls)”;

}

body perms system { mode => “0640”; } ```

ls /home/user/test_plain.txt

/var/cfengine/bin/cf-agent –no-lock –file ./file_test.cf –bundlesequence list_file,testbundle,list_file_2

/var/cfengine/bin/cf-agent –no-lock –file ./file_test.cf –bundlesequence list_file,list_file_2

ls /home/user/test_plain.txt

rm /home/user/test_plain.txt

Delete a File

```cf3 body common control {

inputs => {
   "libraries/cfengine_stdlib.cf",
}; }

bundle agent testbundle {

files: “/home/user/test_plain.txt” perms => system, create => “true”; }

bundle agent test_delete {

files: “/home/user/test_plain.txt” delete => tidy; }

bundle agent list_file {

vars: “ls” slist => lsdir(“/home/user”,”test_plain.txt”,”true”);

reports: “ls: $(ls)”;

}

bundle agent list_file_2 {

vars: “ls” slist => lsdir(“/home/user”,”test_plain.txt”,”true”);

reports: “ls: $(ls)”;

}

body perms system { mode => “0640”; } ```

rm /home/user/test_plain.txt

ls /home/user/test_plain.txt

/var/cfengine/bin/cf-agent –no-lock –file ./file_test.cf –bundlesequence list_file,testbundle,list_file_2

/var/cfengine/bin/cf-agent –no-lock –file ./file_test.cf –bundlesequence list_file,list_file_2

/var/cfengine/bin/cf-agent –no-lock –file ./file_test.cf –bundlesequence list_file,test_delete,list_file_2

ls /home/user/test_plain.txt

rm /home/user/test_plain.txt

(last command will throw an error because the file doesn’t exist!)

Modify a File

rm /home/user/test_plain.txt

ls /home/user/test_plain.txt

/var/cfengine/bin/cf-agent –no-lock –file ./file_test.cf –bundlesequence list_file,testbundle,list_file_2

/var/cfengine/bin/cf-agent –no-lock –file ./file_test.cf –bundlesequence list_file,list_file_2

```cf3 body common control {

inputs => {
   "libraries/cfengine_stdlib.cf",
}; }

bundle agent testbundle {

files: “/home/user/test_plain.txt” perms => system, create => “true”; }

bundle agent test_delete {

files: “/home/user/test_plain.txt” delete => tidy; }

bundle agent list_file {

vars: “ls” slist => lsdir(“/home/user”,”test_plain.txt”,”true”);

reports: “ls: $(ls)”;

}

bundle agent list_file_2 {

vars: “ls” slist => lsdir(“/home/user”,”test_plain.txt”,”true”);

reports: “ls: $(ls)”;

}

Finds the file, if exists calls bundle to edit line

bundle agent outer_bundle_1 { files:

   "/home/user/test_plain.txt"
   create    => "false",
   edit_line => inner_bundle_1; }

Finds the file, if exists calls bundle to edit line

bundle agent outer_bundle_2 { files:

   "/home/user/test_plain.txt"
   create    => "false",
   edit_line => inner_bundle_2; }

Inserts lines

bundle edit_line inner_bundle_1 { vars:

"msg" string => "Helloz to World!";

insert_lines: “$(msg)”;

}

Replaces lines

bundle edit_line inner_bundle_2 { replace_patterns:

“Helloz to World!” replace_with => hello_world;

}

body replace_with hello_world { replace_value => “Hello World”; occurrences => “all”; }

body perms system { mode => “0640”; } ```

/var/cfengine/bin/cf-agent –no-lock –file ./file_test.cf –bundlesequence list_file,test_delete,list_file_2

ls /home/user/test_plain.txt

rm /home/user/test_plain.txt

Copy a File and Edit its Text

```cf3

body common control {

inputs => {
   "libraries/cfengine_stdlib.cf",
}; }

bundle agent testbundle {

files: “/home/ichien/test_plain.txt” perms => system, create => “true”;

reports: “test_plain.txt has been created”; }

bundle agent test_delete {

files: “/home/ichien/test_plain.txt” delete => tidy; }

bundle agent do_files_exist

{ vars:

  "mylist" slist => { "/home/ichien/test_plain.txt", "/home/ichien/test_plain_2.txt" };

classes:

  "exists" expression => filesexist("@(mylist)");

reports:

exists::

  "test_plain.txt and test_plain_2.txt files exist";

!exists::

  "test_plain.txt and test_plain_2.txt files do not exist"; }

bundle agent do_files_exist_2

{ vars:

  "mylist" slist => { "/home/ichien/test_plain.txt", "/home/ichien/test_plain_2.txt" };

classes:

  "exists" expression => filesexist("@(mylist)");

reports:

exists::

  "test_plain.txt and test_plain_2.txt files both exist";

!exists::

  "test_plain.txt and test_plain_2.txt files do not exist"; }

bundle agent list_file_1 {

vars: “ls1” slist => lsdir(“/home/ichien”,”test_plain.txt”,”true”); “ls2” slist => lsdir(“/home/ichien”,”test_plain_2.txt”,”true”);

  "file_content_1" string => readfile( "/home/ichien/test_plain.txt" , "33" );
  "file_content_2" string => readfile( "/home/ichien/test_plain_2.txt" , "33" );   reports:
  #"ls1: $(ls1)";
  #"ls2: $(ls2)";

  "Contents of /home/ichien/test_plain.txt = $(file_content_1)";
  "Contents of /home/ichien/test_plain_2.txt = $(file_content_2)"; }

bundle agent list_file_2 {

vars: “ls1” slist => lsdir(“/home/ichien”,”test_plain.txt”,”true”); “ls2” slist => lsdir(“/home/ichien”,”test_plain2.txt”,”true”); “file_content1” string => readfile( “/home/ichien/test_plain.txt” , “33” ); “file_content2” string => readfile( “/home/ichien/test_plain2.txt” , “33” );

reports: #”ls1: $(ls1)”; #”ls2: $(ls2)”; “Contents of /home/ichien/test_plain.txt = $(file_content1)”; “Contents of /home/ichien/test_plain2.txt = $(file_content_2)”;

}

bundle agent outer_bundle_1 { files:

   "/home/ichien/test_plain.txt"
   create    => "false",
   edit_line => inner_bundle_1; }

Copies file

bundle agent copy_a_file { files:

  "/home/ichien/test_plain_2.txt"
  copy_from => local_cp("/home/ichien/test_plain.txt");

reports: “test_plain.txt has been copied to test_plain_2.txt”; }

bundle agent outer_bundle_2 { files:

   "/home/ichien/test_plain_2.txt"
   create    => "false",
   edit_line => inner_bundle_2; }

bundle edit_line inner_bundle_1 { vars:

"msg" string => "Helloz to World!";

insert_lines: “$(msg)”;

reports: “inserted $(msg) into test_plain.txt”;

}

bundle edit_line inner_bundle_2 { replace_patterns:

“Helloz to World!” replace_with => hello_world;

reports: “Text in test_plain_2.txt has been replaced”;

}

body replace_with hello_world { replace_value => “Hello World”; occurrences => “all”; }

body perms system { mode => “0640”; }

```

console /var/cfengine/bin/cf-agent --no-lock --file ./file_test.cf --bundlesequence test_delete,do_files_exist,testbundle,outer_bundle_1,copy_a_file,do_files_exist_2,list_file_1,outer_bundle_2,list_file_2