Usage¶
Basic Usage¶
Once installed you can use the vncdotool command to send key-presses. Alphanumerics are straightforward just specify the character. For other keys longer names are used:
> vncdo key a
> vncdo key 5
> vncdo key .
> vncdo key enter
> vncdo key shift-a
> vncdo key ctrl-C
> vncdo key ctrl-alt-del
To type longer strings when entering data or commands you can use the type c command, which does not support special characters:
> vncdo type "hello world"
You can control the mouse pointer with move and click commands. NOTE, you should almost always issue a move before a click, as in:
> vncdo move 100 100 click 1
The following would seem to be equivalent but would actually click at (0, 0). This occurs due to how click events are encoded by VNC, meaning you need to initialise the position of the mouse.:
> vncdo move 100 100
> vncdo click 1
If you have the Python Imaging Library (Pillow) installed you can also make screen captures of the session:
> vncdo capture screenshot.png
With Pillow installed, you can wait for the screen to match a known image:
> vncdo expect somescreen.png 0
Putting it all together you can specify multiple actions on a single command line. You could automate a login with the following:
> vncdo type username key enter expect password_prompt.png
> vncdo type password move 100 150 click 1 expect welcome_screen.png
Sometimes you only care about a portion of the screen, in which case you can use rcapture and rexpect. For instance, if your login window appears at x=100, y=200 and is 400 pixels wide by 250 high you could do:
> vncdo rcapture region.png 100 200 400 250
> vncdo rexpect region.png 100 200 0
Exit Status¶
vncdo exits 0 when every action completed. Failures are grouped by cause, so a script can tell a server that is down from one that rejected the password:
> vncdo -s $HOST -p $PASSWORD type hello
> case $? in
> 0) echo "done" ;;
> 3) echo "wrong password" ;;
> 1?) echo "cannot reach $HOST" ;;
> *) echo "failed" ;;
> esac
Code |
Meaning |
|---|---|
0 |
all actions completed |
1 |
unexpected error |
2 |
bad command line or unknown action |
3 |
authentication failed, usually a wrong password |
10 |
could not connect: refused, unreachable, or name lookup failed |
11 |
connection closed before the actions finished |
20 |
server spoke something we could not understand |
30 |
an action failed, such as writing a capture to an unwritable path |
40 |
|
Single digits are for things you told us: the command line and the credentials. Failures out on the wire are grouped in tens by cause, so new codes can be added to a group later. Match on the group when you only care about the category.
Running Scripts¶
For more complex automation you can read commands from stdin or a file. The file format is simply a collection of actions:
> echo "type hello" | vncdo -
Or if you had a file called login.vdo with the following content:
# select the name text box, enter your name and submit
move 100 100 click 1 type "my name" key tab key enter
# grab the result
capture screenshot.png
You could run it with the following command:
> vncdo login.vdo
Creating Scripts¶
While you can create scripts by hand it can often be a time consuming process. To make the process easier vncdotool provides a log mode that allows a user to record a VNC session to a script which is playable by vncdo. vnclog act as a man-in-the-middle to record the VNC commands you issue with a client. So you will have your vnclog connect to your server and your viewer connect to vnclog
vncviewer —> vnclog —> vncserver
For best results be sure to set your vncviewer client to use the RAW encoding. Others encoding may work but are not fully supported at this time.
The quickest way to get started is to run:
> vnclog --viewer vncviewer keylog.vdo
For more control you can launch the viewer separately but be sure to connect to the correct ports:
> vnclog keylog.vdo
> vncviewer localhost:2 # do something and then exit viewer
> vncdo keylog.vdo
By running with –file-per-client vnclog will create a new file for every client connection and record each clients activity. This can be useful for quickly recording a number of testcases.:
> vnclog --file-per-client --listen 6000 /tmp
> vncviewer localhost::6000
# do some stuff then exit and start new session
> vncviewer localhost::6000
# do some other stuff
> ls /tmp/*.vdo
vnclog keeps accepting connections until you stop it. Use --one-shot
to record a single session and exit:
> vnclog --one-shot --listen 6000 keylog.vdo