Saving the screenshots

resources/archive/shot_saver.py

This module provides a high-level interface for saving screenshots asynchronously in the form of the ShotSaver class.

Class arguments

• pool_size (int, optional): Maximum number of simultaneously saved screenshots. 10 by default.
• callback (callable[str, str], optional): Callback function that is called after the screenshots are saved. The guid of the task to save and the current status of the task are passed to this function.

Class public attributes

• timeout_sec (int): Screenshot waiting time, sec. 10 by default.
• buffer_ts(int): Waiting time for creating a screenshot with figures. 0 by default.
• max_tries (int): Number of attempts to save a screenshot. 2 by default.
• callback (callable[str, str]): Same as the callback argument.
• pool_size (int): Same as the pool_size argument.
• screenshots_folder (str): Screenshots folder by default, if no other is specified when calling the method. Server screenshot folder by default.

Class methods

• save - Saves a screenshot to a file. Returns task's guid and a path, where the screenshot will be saved.
  Method's arguments:
  
  • channel_full_guid (str): Channel guid in a form of ChannelGuid_ServerGuid .
  • dt (datetime.datetime, optional): Date and time of a screenshot saving. Current date and time by default.
  • figures (bool, optional): If True - saves a screenshot with figures. False by default.
  • file_name (str, optional): Screenshot name. By default, it is generated according to the template  {channel.name} (%Y.%m.%d %H-%M-%S.%f).jpg
    In the screenshot name, date and time formatting is supported (available arguments are at https://strftime.org/) as well as channel and server objects.
  • file_path (str, optional): Full name for screenshot saving. By default, screenshot will be saved in the directory, defined in screenshots_folder attribute.
  • callback (callable[str, str], optional): Callback function that is called after screenshots are saved. The guid of the task to save and the current status of the task are passed to this function. If not defined - callback of class is used.
  • task_guid (str, optional): Task's guid. host.random_guid() function define it by default.
• get - Returns image in callback, bytes
  Method arguments:
  • channel_full_guid (str): Channel guid in a form of ChannelGuid_ServerGuid .
  • dt (datetime.datetime, optional): Date and time of a screenshot saving. Current date and time by default.
  • figures (bool, optional): If True - saves a screenshot with figures. False by default.
  • callback (callable[str, str]): Callback function that is called after screenshots are saved. The guid of the task to save and the current status of the task are passed to this function. If not defined - callback of class is used. Raises EnvironmentError if callback of class is also not defined.

Possible states of screenshot saving are contained in the status object:

• status.saving - Screenshot is being saved.
• status.error - Error of screenshot saving.
• status.success - Screenshot is successfully saved.
• status.in_queue - Screenshot is added to a saving queue.

Code examples

Simple example

Saving the current screenshot from the channel with a standard name to the screenshots folder.

from shot_saver import ShotSaver

CHANNEL_GUID = "uR76TlcA_O4Yazs8u"  # Must be replaced with the guid of your channel

ss = ShotSaver()

ss.save(CHANNEL_GUID)

Changing the folder of screenshots saving

If you want all screenshots of this script to be saved in a separate folder, you can change it globally for the entire class.

from shot_saver import ShotSaver

CHANNEL_GUID = "uR76TlcA_O4Yazs8u"  # Must be replaced with the guid of your channel 

ss = ShotSaver()
ss.screenshots_folder = r"D:\DSSL\shots"

ss.save(CHANNEL_GUID)

Or assign directly when saving a screenshot

from shot_saver import ShotSaver

CHANNEL_GUID = "uR76TlcA_O4Yazs8u"  # Must be replaced with the guid of your channel 

ss = ShotSaver()

ss.save(CHANNEL_GUID, file_path=r"D:\DSSL\shots")

Screenshot request for a specific date / time

We can also change the name of the screenshot, and / or add the date / time for which we want to save the screenshot.
For example, let's save a screenshot for the current date, and change the time to 00:00:00 .

import datetime
from shot_saver import ShotSaver

CHANNEL_GUID = "uR76TlcA_O4Yazs8u"  # Must be replaced with the guid of your channel 

ss = ShotSaver()

dt = datetime.datetime.combine(
    datetime.datetime.now().date(),  # Current date
    datetime.time()  # Время 00:00:00
)
ss.save(CHANNEL_GUID, dt=dt, file_name="midnight_shot.jpg")

Tracking of the screenshot saving status

Upon successful saving, the resulting image is opened.
We use the tasks variable to store the current tasks and the paths for the screenshot saves for each task.

import os
import host
from shot_saver import ShotSaver, status

CHANNEL_GUID = "uR76TlcA_O4Yazs8u"

ss = ShotSaver()

tasks = {}


def callback(guid, state):
    host.message("[%s] %s" % (guid, state))  # Displaying the current task status
    if state == status.success:
        # Opening the image if the screenshot was successfully saved 
        fpath = tasks.pop(guid)
        os.startfile(fpath)
    elif state == status.error:
        # Removing the task from the list if an error occurs 
        fpath = tasks.pop(guid)
        host.message("Can't save shot: %s" % fpath)


task_guid, file_path = ss.save(CHANNEL_GUID, callback=callback)
tasks[task_guid] = file_path

Getting an image in bytes

For example, to display in a window host.question

import base64
import host
from shot_saver import ShotSaver

CHANNEL_GUID = "uR76TlcA_O4Yazs8u"

ss = ShotSaver()

__image_html = """<img src="data:image/png;base64,{img}" width="800">"""


def show_image(image_bytes):
    host.question(
        __image_html.format(img=base64.b64encode(image_bytes)),
        "OK", lambda: 0
    )


ss.get(CHANNEL_GUID, callback=show_image)