add dynamic config commands

config.toml

@@ -30,3 +30,7 @@ font = "./res/curie.bdf"
 text_filters = [ "lowercase" ]
 text_offset = [45, 4]
 text_fill = [255, 255, 255] # your template image must have alpha channel to use alpha
+
+[[image]]
+output = "out/iloveseason.gif"
+command = [ "python", "./res/iloveseason.py" ]

readme.md

@@ -12,7 +12,7 @@ such as nginx or caddy.
 1. install requirements: `pip install -r requirements.txt`
 2. run: `python main/src.py [-c config-file] [-L]`.
 
-## docker
+### docker
 
 a [dockerfile](./Dockerfile) and [compose file](./compose.yaml) have been provided.
 keep in mind the commands will run in the docker container, too.
@@ -37,6 +37,36 @@ RUN apt-get update && apt-get install blahblahblah
 CMD [ "python", "-u", "./src/main.py", "-c", "/config.toml" ]
 ```
 
+## writing commands
+
+### basic
+
+basic commands return just text.
+the text can end in 0 or 1 newlines but not multiple,
+else it will be interpreted as a dynamic config command.
+
+### dynamic config commands
+
+any config can be dynamically set by preceeding the text to be printed
+with TOML config:
+
+```
+template = "pat/to/templat.gif"
+font = "fonts/custom_font.bdf"
+text_offset = [20, 4]
+hello world
+```
+
+if you do not want to print any text,
+simply leave an extra blank/empty line
+(the text ends in two newlines)
+or a space character:
+
+```
+template = "pat/to/templat.gif"
+
+```
+
 ## config
 
 the provided [example config file](./config.toml) lists all the options that can be used.

res/iloveseason.py

@@ -0,0 +1,42 @@
+#!/usr/bin/env python3
+#
+# Akbar Rahman <hi@alv.cx>
+#
+
+import sys
+from datetime import datetime as dt
+
+
+def get_args():
+    """ Get command line arguments """
+
+    import argparse
+    parser = argparse.ArgumentParser()
+    return parser.parse_args()
+
+
+def main(args):
+    """ Entry point for script """
+    now = dt.now()
+
+    template = ""
+    if now.month in [3, 4, 5]:
+        template = './res/spring.gif'
+    if now.month in [6, 7, 8]:
+        template = './res/summer.gif'
+    if now.month in [9, 10, 11]:
+        template = './res/autumn.gif'
+    if now.month in [12, 1, 2]:
+        template = './res/winter.gif'
+
+    print(f'template = "{template}"')
+    print()
+
+    return 0
+
+
+if __name__ == '__main__':
+    try:
+        sys.exit(main(get_args()))
+    except KeyboardInterrupt:
+        sys.exit(0)

src/main.py

@@ -3,6 +3,7 @@
 # Akbar Rahman <hi@alv.cx>
 #
 
+import json
 import sys
 import subprocess
 import time
@@ -22,22 +23,36 @@ def get_args():
 
 
 def generate(config):
-    if config.get('template'):
-        img = Image.open(config['template'])
-    else:
-        img = Image.new(mode="RGBA", size = config['size'])
-
-    draw = ImageDraw.Draw(img)
-    with open(config['font'], "rb") as fp:
-        font = BdfFontFile.BdfFontFile(fp).to_imagefont()
-
     process = subprocess.run(config['command'], stdout=subprocess.PIPE, shell=False)
     if process.returncode != config.get('return_code', 0):
         # process did not run succesfully.
         # do not risk displaying that to user
         return
+    cmd_output = process.stdout.decode('utf-8').split('\n')
+    print(f"{cmd_output=}")
+    dynamic_config = {}
+    if len(cmd_output) > 2:
+        dynamic_config = tomllib.loads('\n'.join(cmd_output[:-2]))
+        text = cmd_output[-2]
+    else:
+        text = cmd_output[0]
+
+    print(f"{dynamic_config=}")
+    for key, val in dynamic_config.items():
+        config[key] = val
+
+    if config.get('template'):
+        img = Image.open(config['template'])
+    else:
+        img = Image.new(mode="RGBA", size = config['size'])
+
+    print(f"{text=}")
+
+    if text:
+        draw = ImageDraw.Draw(img)
+        with open(config['font'], "rb") as fp:
+            font = BdfFontFile.BdfFontFile(fp).to_imagefont()
 
-    text = process.stdout.decode('utf-8').split('\n')[0]
         for filter in config.get('text_filters', []):
             if filter == "lowercase":
                 text = text.lower()