Pre Build Script

roel

Hi,

I want to run a python script before i build and run my project. I noticed i can create my own run.sh inside the project directory. I can call the python script from there, but how do i then build and run the project as would normally happen when clicking on the build and run button.

Thanks!

giuliomoro

The IDE calls make -C /root/Bela all PROJECT=ProjectName to build the project, followed by make -C /root/Bela runide PROJECT=ProjectName CL="..." to run it, where "..." are the command line options built from the project settings in the IDE. The Makefile looks for a file RUN_FILE?=$(PROJECT_DIR)/run.sh. If it finds it, it doesn't build anything and it just executes the file.

From your own run.sh file you can call make RUN_FILE=/non/existing/path PROJECT=ProjectName run CL="...". This will override RUN_FILE so that it points to a non-existing path, then make will not find it and therefore build and run the project as if run.sh was not there.

roel

Thanks! I got it working. Not sure if this is the best way to do it since i had to write a small script to parse the IDE settings from the settings.json file to command line parameters for make.

Is there a better way to do that? This is my run.sh

echo  "Building project from custom build script"
python create_config.py
echo "Succesfully run pre-build script"

CL=$(python parse_cl_args.py)
echo "$CL"
make -C /root/Bela RUN_FILE=/non/exisiting/path PROJECT=AudioPlayer run CL="$CL"

giuliomoro

roel python create_config.py

Another alternative is to add a custom target to the Makefile and make that a prerequisite of the all target. For this purpose, you could create a CustomMakefileTop.in (which is automatically included by the Makefile). In that file, you'd put:

all: prebuild

prebuild:
	@echo prebuild target for project $(PROJECT)
	python create_config.py

though this would apply to all projects on the board.

giuliomoro

That's the sort of thing you need to do it "properly" (please share parse_cl_args.py). I tend to be more low-tech: I just run the program once via the IDE, then look in journalctl -fu bela_ide for what actually gets run and copy that and hardcode it in my script.

roel

Ok cool, good to know. Here is the python script for parsing the cl args:

import json
import re

with open("settings.json") as f:
    settings = json.load(f)

clargs = settings.get("CLArgs", {})
cmd_parts = []

for key, value in clargs.iteritems(): 
    if not value:
        continue
    
    # Doesn't seem like a valid argument
    if key == "audioExpander":
        continue
	
    # Channel gains need a comma, rest don't
    m = re.match(r"(-[HI])(\d+),?$", key)
    if not m:
	key = key.replace(",", "")
    
    # Add extra space for long arguments
    m = re.match(r"^--", key)
    space = ""
    if m:
        space = " "
        
    cmd_parts.append(key + space + str(value))

print(" ".join(cmd_parts))

giuliomoro

Even more fun, I don't think we are doing a lot of escaping/sanitisation of the content of the User Command Line Arguments textbox: you could inject some bash in there. For instance, instead of typing --help in there, you could type

`echo --help`

then running the program you will get its help printout.

In your case, you could add in User Command Line Arguments:

`cd projects/MYPROJECT && python create_config.py`

Don't rely on this "feature" to stay there forever ;-).