Source code for sewerrat.start_sewerrat

from typing import Optional, Tuple
import requests
import os
import time
from . import _utils as ut


test_api_process = None
test_api_port = None




def start_sewerrat(db: Optional[str] = None, port: Optional[int] = None, wait: float = 1, version: str = "1.1.0", overwrite: bool = False) -> Tuple[bool, int]:
    """
    Start a test SewerRat service.

    Args:
        db: 
            Path to a SQLite database. If None, one is automatically created.

        port:
            An available port. If None, one is automatically chosen.

        wait:
            Number of seconds to wait for the service to initialize before use.

        version:
            Version of the service to run.

        overwrite:
            Whether to overwrite the existing Gobbler binary.

    Returns:
        A tuple indicating whether a new test service was created (or an
        existing instance was re-used) and its URL. If a service is already
        running, this function is a no-op and the configuration details of the
        existing service will be returned.
    """
    global test_api_port

    if test_api_process is not None:
        return False, "http://0.0.0.0:" + str(test_api_port)

    exe = _acquire_sewerrat_binary(version, overwrite)
    _initialize_sewerrat_process(exe, db, port)

    time.sleep(1) # give it some time to spin up.
    return True, "http://0.0.0.0:" + str(test_api_port)



def _acquire_sewerrat_binary(version: str, overwrite: bool):
    import platform
    sysname = platform.system()
    if sysname == "Darwin":
        OS = "darwin"
    elif sysname == "Linux":
        OS = "linux"
    else:
        raise ValueError("unsupported operating system '" + sysname + "'")

    sysmachine = platform.machine()
    if sysmachine == "arm64":
        arch = "arm64"
    elif sysmachine == "x86_64":
        arch = "amd64"
    else:
        raise ValueError("unsupported architecture '" + sysmachine + "'")

    import appdirs
    cache = appdirs.user_data_dir("SewerRat", "aaron")
    desired = "SewerRat-" + OS + "-" + arch
    exe = os.path.join(cache, desired + "-" + version)

    if not os.path.exists(exe) or overwrite:
        url = "https://github.com/ArtifactDB/SewerRat/releases/download/" + version + "/" + desired

        import shutil
        os.makedirs(cache, exist_ok=True)
        tmp = exe + ".tmp"
        ut.download_file(url, tmp)
        os.chmod(tmp, 0o755)

        # Using a write-and-rename paradigm to provide some atomicity. Note
        # that renaming doesn't work across different filesystems so in that
        # case we just fall back to copying.
        try:
            shutil.move(tmp, exe)
        except:
            shutil.copy(tmp, exe)

    return exe
   

def _initialize_sewerrat_process(exe: str, db: Optional[str], port: Optional[int]):
    if port is None:
        import socket
        with socket.socket(socket.AF_INET) as s:
            s.bind(('0.0.0.0', 0))
            port = s.getsockname()[1]

    if db is None:
        import tempfile
        host = tempfile.mkdtemp()
        db = os.path.join(host, "index.sqlite3")

    global test_api_port
    global test_api_process
    test_api_port = port

    import subprocess
    test_api_process = subprocess.Popen([ exe, "-db", db, "-port", str(port) ], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)

    import atexit
    atexit.register(stop_sewerrat)
    return




def stop_sewerrat():
    """
    Stop the SewerRat test service started by :py:func:`~.start_sewerrat`. If
    no test service was running, this function is a no-op.
    """
    global test_api_process
    global test_api_port

    if test_api_process is not None:
        test_api_process.terminate()
        test_api_process = None
        test_api_port = None
    return