- Resources
- provisioners
- File Provisioner
File Provisioner
The file
provisioner copies files or directories from the machine
running OpenTF to the newly created resource. The file
provisioner
supports both ssh
and winrm
type connections.
Use provisioners as a last resort. There are better alternatives for most situations. Refer to Declaring Provisioners for more details.
Example usage
resource "aws_instance" "web" {
# ...
# Copies the myapp.conf file to /etc/myapp.conf
provisioner "file" {
source = "conf/myapp.conf"
destination = "/etc/myapp.conf"
}
# Copies the string in content into /tmp/file.log
provisioner "file" {
content = "ami used: ${self.ami}"
destination = "/tmp/file.log"
}
# Copies the configs.d folder to /etc/configs.d
provisioner "file" {
source = "conf/configs.d"
destination = "/etc"
}
# Copies all files and folders in apps/app1 to D:/IIS/webapp1
provisioner "file" {
source = "apps/app1/"
destination = "D:/IIS/webapp1"
}
}
When the file
provisioner communicates with a Windows system over SSH, you must configure OpenSSH to run the commands with cmd.exe
and not PowerShell. PowerShell causes file parsing errors because it is incompatible with both Unix shells and the Windows command interpreter.
Argument Reference
The following arguments are supported:
source
- The source file or directory. Specify it either relative to the current working directory or as an absolute path. This argument cannot be combined withcontent
.content
- The direct content to copy on the destination. If destination is a file, the content will be written on that file. In case of a directory, a file namedtf-file-content
is created inside that directory. We recommend using a file as the destination when usingcontent
. This argument cannot be combined withsource
.destination
- (Required) The destination path to write to on the remote system. See Destination Paths below for more information.
Destination Paths
The path you provide in the destination
argument will be evaluated by the
remote system, rather than by OpenTF itself. Therefore the valid values
for that argument can vary depending on the operating system and remote access
software running on the target.
When connecting over SSH, the file
provisioner passes the given destination
path verbatim to the scp
program on the remote host. By default, OpenSSH's
scp
implementation runs in the remote user's home directory and so you can
specify a relative path to upload into that home directory, or an absolute
path to upload to some other location. The remote scp
process will run with
the access level of the user specified in the connection
block, and so
permissions may prevent writing directly to locations outside of the home
directory.
Because WinRM has no corresponding file transfer protocol, for WinRM
connections the file
provisioner uses a more complex process:
- Generate a temporary filename in the directory given in the remote system's
TEMP
environment variable, using a pseudorandom UUID for uniqueness. - Use sequential generated
echo
commands over WinRM to gradually append base64-encoded chunks of the source file to the chosen temporary file. - Use an uploaded PowerShell script to read the temporary file, base64-decode, and write the raw result into the destination file.
In the WinRM case, the destination path is therefore interpreted by PowerShell
and so you must take care not to use any meta-characters that PowerShell might
interpret. In particular, avoid including any untrusted external input in
your destination
argument when using WinRM, because it can serve as a vector
for arbitrary PowerShell code execution on the remote system.
Modern Windows systems support running an OpenSSH server, so we strongly recommend choosing SSH over WinRM whereever possible, and using WinRM only as a last resort when working with obsolete Windows versions.
Directory Uploads
The file
provisioner can upload a complete directory to the remote machine.
When uploading a directory, there are some additional considerations.
When using the ssh
connection type the destination directory must already
exist. If you need to create it, use a remote-exec provisioner just prior to
the file provisioner in order to create the directory
When using the winrm
connection type the destination directory will be
created for you if it doesn't already exist.
The existence of a trailing slash on the source path will determine whether the directory name will be embedded within the destination, or whether the destination will be created. For example:
If the source is
/foo
(no trailing slash), and the destination is/tmp
, then the contents of/foo
on the local machine will be uploaded to/tmp/foo
on the remote machine. Thefoo
directory on the remote machine will be created by OpenTF.If the source, however, is
/foo/
(a trailing slash is present), and the destination is/tmp
, then the contents of/foo
will be uploaded directly into/tmp
.