httpie-cli/tests/utils.py

# coding=utf-8
"""Utilities for HTTPie test suite."""
import os
import sys
import time
import json
import tempfile
from pathlib import Path
from typing import Optional

from httpie import ExitStatus
from httpie.config import Config
from httpie.context import Environment
from httpie.core import main


TESTS_ROOT = os.path.abspath(os.path.dirname(__file__))
CRLF = '\r\n'
COLOR = '\x1b['
HTTP_OK = '200 OK'
HTTP_OK_COLOR = (
    'HTTP\x1b[39m\x1b[38;5;245m/\x1b[39m\x1b'
    '[38;5;37m1.1\x1b[39m\x1b[38;5;245m \x1b[39m\x1b[38;5;37m200'
    '\x1b[39m\x1b[38;5;245m \x1b[39m\x1b[38;5;136mOK'
)


def mk_config_dir() -> Path:
    dirname = tempfile.mkdtemp(prefix='httpie_config_')
    return Path(dirname)


def add_auth(url, auth):
    proto, rest = url.split('://', 1)
    return proto + '://' + auth + '@' + rest


class MockEnvironment(Environment):
    """Environment subclass with reasonable defaults for testing."""
    colors = 0
    stdin_isatty = True,
    stdout_isatty = True
    is_windows = False

    def __init__(self, create_temp_config_dir=True, **kwargs):
        if 'stdout' not in kwargs:
            kwargs['stdout'] = tempfile.TemporaryFile(
                mode='w+b',
                prefix='httpie_stdout'
            )
        if 'stderr' not in kwargs:
            kwargs['stderr'] = tempfile.TemporaryFile(
                mode='w+t',
                prefix='httpie_stderr'
            )
        super().__init__(**kwargs)
        self._create_temp_config_dir = create_temp_config_dir
        self._delete_config_dir = False
        self._temp_dir = Path(tempfile.gettempdir())

    @property
    def config(self) -> Config:
        if (self._create_temp_config_dir
                and self._temp_dir not in self.config_dir.parents):
            self.config_dir = mk_config_dir()
            self._delete_config_dir = True
        return super().config

    def cleanup(self):
        self.stdout.close()
        self.stderr.close()
        if self._delete_config_dir:
            assert self._temp_dir in self.config_dir.parents
            from shutil import rmtree
            rmtree(self.config_dir)

    def __del__(self):
        try:
            self.cleanup()
        except Exception:
            pass


class BaseCLIResponse:
    """
    Represents the result of simulated `$ http' invocation  via `http()`.

    Holds and provides access to:

        - stdout output: print(self)
        - stderr output: print(self.stderr)
        - exit_status output: print(self.exit_status)

    """
    stderr: str = None
    json: dict = None
    exit_status: ExitStatus = None


class BytesCLIResponse(bytes, BaseCLIResponse):
    """
    Used as a fallback when a StrCLIResponse cannot be used.

    E.g. when the output contains binary data or when it is colorized.

    `.json` will always be None.

    """


class StrCLIResponse(str, BaseCLIResponse):

    @property
    def json(self) -> Optional[dict]:
        """
        Return deserialized JSON body, if one included in the output
        and is parsable.

        """
        if not hasattr(self, '_json'):
            self._json = None
            # De-serialize JSON body if possible.
            if COLOR in self:
                # Colorized output cannot be parsed.
                pass
            elif self.strip().startswith('{'):
                # Looks like JSON body.
                self._json = json.loads(self)
            elif (self.count('Content-Type:') == 1
                    and 'application/json' in self):
                # Looks like a whole JSON HTTP message,
                # try to extract its body.
                try:
                    j = self.strip()[self.strip().rindex('\r\n\r\n'):]
                except ValueError:
                    pass
                else:
                    try:
                        # noinspection PyAttributeOutsideInit
                        self._json = json.loads(j)
                    except ValueError:
                        pass
        return self._json


class ExitStatusError(Exception):
    pass


def http(*args, program_name='http', **kwargs):
    # noinspection PyUnresolvedReferences
    """
    Run HTTPie and capture stderr/out and exit status.

    Invoke `httpie.core.main()` with `args` and `kwargs`,
    and return a `CLIResponse` subclass instance.

    The return value is either a `StrCLIResponse`, or `BytesCLIResponse`
    if unable to decode the output.

    The response has the following attributes:

        `stdout` is represented by the instance itself (print r)
        `stderr`: text written to stderr
        `exit_status`: the exit status
        `json`: decoded JSON (if possible) or `None`

    Exceptions are propagated.

    If you pass ``tolerate_error_exit_status=True``, then error exit statuses
    won't result into an exception.

    Example:

    $ http --auth=user:password GET httpbin.org/basic-auth/user/password

        >>> httpbin = getfixture('httpbin')
        >>> r = http('-a', 'user:pw', httpbin.url + '/basic-auth/user/pw')
        >>> type(r) == StrCLIResponse
        True
        >>> r.exit_status
        <ExitStatus.SUCCESS: 0>
        >>> r.stderr
        ''
        >>> 'HTTP/1.1 200 OK' in r
        True
        >>> r.json == {'authenticated': True, 'user': 'user'}
        True

    """
    tolerate_error_exit_status = kwargs.pop('tolerate_error_exit_status', False)
    env = kwargs.get('env')
    if not env:
        env = kwargs['env'] = MockEnvironment()

    stdout = env.stdout
    stderr = env.stderr

    args = list(args)
    args_with_config_defaults = args + env.config.default_options
    add_to_args = []
    if '--debug' not in args_with_config_defaults:
        if not tolerate_error_exit_status and '--traceback' not in args_with_config_defaults:
            add_to_args.append('--traceback')
        if not any('--timeout' in arg for arg in args_with_config_defaults):
            add_to_args.append('--timeout=3')

    complete_args = [program_name, *add_to_args, *args]

    def dump_stderr():
        stderr.seek(0)
        sys.stderr.write(stderr.read())

    try:
        try:
            exit_status = main(args=complete_args, **kwargs)
            if '--download' in args:
                # Let the progress reporter thread finish.
                time.sleep(.5)
        except SystemExit:
            if tolerate_error_exit_status:
                exit_status = ExitStatus.ERROR
            else:
                dump_stderr()
                raise
        except Exception:
            stderr.seek(0)
            sys.stderr.write(stderr.read())
            raise
        else:
            if not tolerate_error_exit_status and exit_status != ExitStatus.SUCCESS:
                dump_stderr()
                raise ExitStatusError(
                    'httpie.core.main() unexpectedly returned'
                    f' a non-zero exit status: {exit_status}'
                )

        stdout.seek(0)
        stderr.seek(0)
        output = stdout.read()
        try:
            output = output.decode('utf8')
        except UnicodeDecodeError:
            r = BytesCLIResponse(output)
        else:
            r = StrCLIResponse(output)
        r.stderr = stderr.read()
        r.exit_status = exit_status

        if r.exit_status != ExitStatus.SUCCESS:
            sys.stderr.write(r.stderr)

        return r

    finally:
        stdout.close()
        stderr.close()
        env.cleanup()