antlr4_tool_runner.py

import argparse
import os
import sys
import re
import subprocess
from shutil import which
from pathlib import Path
from urllib.request import urlopen
from urllib import error
import json

import jdk  # requires install-jdk package

mvn_repo: str
homedir: Path


def initialize_paths():
    global mvn_repo, homedir
    homedir = Path.home()
    mvn_repo = os.path.join(homedir, '.m2', 'repository', 'org', 'antlr', 'antlr4')


def latest_version():
    try:
        with urlopen(f"https://search.maven.org/solrsearch/select?q=a:antlr4-master+g:org.antlr",
                     timeout=10) as response:
            s = response.read().decode("UTF-8")
            searchResult = json.loads(s)['response']
            # searchResult = s.json()['response']
            antlr_info = searchResult['docs'][0]
            # print(json.dump(searchResult))
            latest = antlr_info['latestVersion']
            return latest
    except (error.URLError, error.HTTPError, TimeoutError):
        print("Could not get latest version number, attempting to fall back to latest downloaded version...")
        version_dirs = list(filter(lambda directory: re.match(r"[0-9]+\.[0-9]+\.[0-9]+", directory), os.listdir(mvn_repo)))
        version_dirs.sort(reverse=True)
        if len(version_dirs) == 0:
            raise FileNotFoundError("Could not find a previously downloaded antlr4 jar")
        else:
            latest_version_dir = version_dirs.pop()
            print(f"Found version '{latest_version_dir}', this version may be out of date")
            return latest_version_dir


def antlr4_jar(version):
    jar = os.path.join(mvn_repo, version, f'antlr4-{version}-complete.jar')
    if not os.path.exists(jar):
        return download_antlr4(jar, version)
    return jar


def download_antlr4(jar, version):
    s = None
    try:
        with urlopen(f"https://repo1.maven.org/maven2/org/antlr/antlr4/{version}/antlr4-{version}-complete.jar",
                     timeout=60) as response:
            print(f"Downloading antlr4-{version}-complete.jar")
            os.makedirs(os.path.join(mvn_repo, version), exist_ok=True)
            s = response.read()
    except (error.URLError, error.HTTPError, TimeoutError):
        print(f"Could not find antlr4-{version}-complete.jar at maven.org")

    if s is None:
        return None
    with open(jar, "wb") as f:
        f.write(s)
    return jar


def find_bin_dir(install_dir):
    for root, dirs, files in os.walk(install_dir):
        if root.endswith("bin"):
            return root
    return None


def install_jre(java_version='11'):
    USER_DIR = os.path.expanduser("~")
    JRE_DIR = os.path.join(USER_DIR, ".jre")
    if os.path.exists(JRE_DIR):
        for f in os.listdir(JRE_DIR):
            if f.startswith(f"jdk-{java_version}"):
                install_dir = os.path.join(JRE_DIR, f)
                bindir = find_bin_dir(install_dir)
                java = os.path.join(bindir, 'java')
                return java

    r = input(f"ANTLR tool needs Java to run; install Java JRE 11 yes/no (default yes)? ")
    if r.strip().lower() not in {'yes', 'y', ''}:
        exit(1)
    install_dir = jdk.install(java_version, jre=True)
    print(f"Installed Java in {install_dir}; remove that dir to uninstall")
    bindir = find_bin_dir(install_dir)
    if bindir is None:
        print(f"Can't find bin/java in {install_dir}; installation failed")
        return None
    java = os.path.join(bindir, 'java')
    return java


def install_jre_and_antlr(version):
    jar = antlr4_jar(version)
    java = which("java")
    if java is None:
        java = install_jre()
    if jar is None or java is None:
        exit(1)
    CHECK_JRE_VERSION = False
    if CHECK_JRE_VERSION:
        p = subprocess.Popen([java, '--version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        out, err = p.communicate()
        out = out.decode("UTF-8").split('\n')[0]
        print(f"Running {out}")
    return jar, java


def process_args():
    parser = argparse.ArgumentParser(
        add_help=False, usage="%(prog)s [-v VERSION] [%(prog)s options]"
    )
    # Note, that the space after `-v` is needed, so we don't pick up other arguments beginning with `v`, like `-visitor`
    parser.add_argument("-v ", dest="version", default=None)
    args, unparsed_args = parser.parse_known_args()

    return unparsed_args, (
            args.version or os.environ.get("ANTLR4_TOOLS_ANTLR_VERSION") or latest_version()
    )


def run_cli(entrypoint):
    initialize_paths()
    args, version = process_args()
    jar, java = install_jre_and_antlr(version)

    cp = subprocess.run([java, '-cp', jar, entrypoint] + args)
    sys.exit(cp.returncode)


def tool():
    """Entry point to run antlr4 tool itself"""
    run_cli('org.antlr.v4.Tool')


def interp():
    """Entry point to run antlr4 profiling using grammar and input file"""
    run_cli('org.antlr.v4.gui.Interpreter')


if __name__ == '__main__':
    interp()