Source code for pywps.inout.basic

# Copyright 2018 Open Source Geospatial Foundation and others    #
# licensed under MIT, Please consult LICENSE.txt for details     #

from pywps._compat import text_type, StringIO
import os
import shutil
import requests
import tempfile
import logging
import pywps.configuration as config
from pywps.inout.literaltypes import (LITERAL_DATA_TYPES, convert,
                                      make_allowedvalues, is_anyvalue,
from pywps import OGCUNIT
from pywps.validator.mode import MODE
from pywps.validator.base import emptyvalidator
from pywps.validator import get_validator
from pywps.validator.literalvalidator import (validate_value,
from pywps.exceptions import NoApplicableCode, InvalidParameterValue, FileSizeExceeded, \
from pywps._compat import PY2, urlparse
import base64
from collections import namedtuple
from copy import deepcopy
from io import BytesIO

SOURCE_TYPE = _SOURCE_TYPE(0, 1, 2, 3, 4)

LOGGER = logging.getLogger("PYWPS")

def _is_textfile(filename):
        # use python-magic if available
        import magic
        is_text = 'text/' in magic.from_file(filename, mime=True)
    except ImportError:
        # read the first part of the file to check for a binary indicator.
        # This method won't detect all binary files.
        blocksize = 512
        fh = open(filename, 'rb')
        is_text = b'\x00' not in
    return is_text

def extend_instance(obj, cls):
    """Apply mixins to a class instance after creation."""
    base_cls = obj.__class__
    base_cls_name = obj.__class__.__name__
    obj.__class__ = type(base_cls_name, (cls, base_cls), {})

class UOM(object):
    :param uom: unit of measure

    def __init__(self, uom=''):
        self.uom = uom

    def json(self):
        return {"reference": OGCUNIT[self.uom],
                "uom": self.uom}

    def __eq__(self, other):
        return self.uom == other.uom

[docs]class IOHandler(object): """Base IO handling class subclassed by specialized versions: FileHandler, UrlHandler, DataHandler, etc. If the specialized handling class is not known when the object is created, instantiate the object with IOHandler. The first time the `file`, `url` or `data` attribute is set, the associated subclass will be automatically registered. Once set, the specialized subclass cannot be switched. :param workdir: working directory, to save temporal file objects in. :param mode: ``MODE`` validation mode. `file` : str Filename on the local disk. `url` : str Link to an online resource. `stream` : FileIO A readable object. `data` : object A native python object (integer, string, float, etc) `base64` : str A base 64 encoding of the data. >>> # setting up >>> import os >>> from io import RawIOBase >>> from io import FileIO >>> >>> ioh_file = IOHandler(workdir=tmp) >>> assert isinstance(ioh_file, IOHandler) >>> >>> # Create test file input >>> fileobj = open(os.path.join(tmp, 'myfile.txt'), 'w') >>> fileobj.write('ASDF ASFADSF ASF ASF ASDF ASFASF') >>> fileobj.close() >>> >>> # testing file object on input >>> ioh_file.file = >>> assert isinstance(ioh_file, FileHandler >>> assert ioh_file.file == >>> assert isinstance(, RawIOBase) >>> # skipped assert isinstance(ioh_file.memory_object, POSH) >>> >>> # testing stream object on input >>> ioh_stream = IOHandler(workdir=tmp) >>> assert ioh_stream.workdir == tmp >>> = FileIO(,'r') >>> assert isinstance(ioh_stream, StreamHandler) >>> assert open(ioh_stream.file).read() == >>> assert isinstance(, RawIOBase) """ prop = None def __init__(self, workdir=None, mode=MODE.NONE): # Internal defaults for class and subclass properties. self._workdir = None self._reset_cache() # Set public defaults self.workdir = workdir self.valid_mode = mode # TODO: Clarify intent self.as_reference = False self.inpt = {} self.uuid = None # request identifier self.data_set = False # This creates dummy property setters and getters for `file`, `data`, `url`, `stream` that # 1. register the subclass methods according to the given property # 2. replace the property setter by the subclass property setter # 3. set the property self._create_fset_properties() def _reset_cache(self): """Sets all internal objects to None.""" self._file = None self._data = None self._post_data = None self._stream = None self._url = None self.data_set = False def _check_valid(self): """Validate this input using given validator """ validate = self.validator _valid = validate(self, self.valid_mode) if not _valid: self.data_set = False raise InvalidParameterValue('Input data not valid using ' 'mode {}'.format(self.valid_mode)) self.data_set = True @property def workdir(self): return self._workdir @workdir.setter def workdir(self, path): """Set working temporary directory for files to be stored in.""" if path is not None: if not os.path.exists(path): os.makedirs(path) self._workdir = path @property def validator(self): """Return the function suitable for validation This method should be overridden by class children :return: validating function """ return emptyvalidator @property def source_type(self): """Return the source type.""" # For backward compatibility only. source_type checks could be replaced by `isinstance`. return getattr(SOURCE_TYPE, self.prop.upper()) def _set_default_value(self, value=None, value_type=None): """Set default value based on input data type.""" value = value or getattr(self, '_default') value_type = value_type or getattr(self, '_default_type') if value: if value_type == SOURCE_TYPE.DATA: = value elif value_type == SOURCE_TYPE.MEMORY: raise NotImplementedError elif value_type == SOURCE_TYPE.FILE: self.file = value elif value_type == SOURCE_TYPE.STREAM: = value elif value_type == SOURCE_TYPE.URL: self.url = value def _build_file_name(self, href=''): """Return a file name for the local system.""" url_path = urlparse(href).path or '' file_name = os.path.basename(url_path).strip() or 'input' (prefix, suffix) = os.path.splitext(file_name) suffix = suffix or self.extension if prefix and suffix: file_name = prefix + suffix input_file_name = os.path.join(self.workdir, file_name) # build tempfile in case of duplicates if os.path.exists(input_file_name): input_file_name = tempfile.mkstemp( suffix=suffix, prefix=prefix + '_', dir=self.workdir)[1] return input_file_name @property def extension(self): """Return the file extension for the data format, if set.""" if getattr(self, 'data_format', None): return self.data_format.extension else: return '' def clone(self): """Create copy of yourself """ return deepcopy(self) @staticmethod def _create_fset_properties(): """Create properties that when set for the first time, will determine the instance's handler class. Example ------- >>> h = IOHandler() >>> isinstance(h, DataHandler) False >>> = 1 # Mixes the DataHandler class to IOHandler. h inherits DataHandler methods. >>> isinstance(h, DataHandler) True Note that trying to set another attribute (e.g. `h.file = 'a.txt'`) will raise an AttributeError. """ for cls in (FileHandler, DataHandler, StreamHandler, UrlHandler): def fset(s, value, kls=cls): """Assign the handler class and set the value to the attribute. This function will only be called once. The next `fset` will use the subclass' property. """ # Add cls methods to this instance. extend_instance(s, kls) # Set the attribute value through the associated cls property. setattr(s, kls.prop, value) setattr(IOHandler, cls.prop, property(fget=lambda x: None, fset=fset))
class FileHandler(IOHandler): prop = 'file' @property def file(self): """Return filename.""" return self._file @file.setter def file(self, value): """Set file name""" self._reset_cache() self._file = os.path.abspath(value) self._check_valid() @property def data(self): """Read file and return content.""" if self._data is None: with open(self.file, mode=self._openmode()) as fh: self._data = return self._data @property def base64(self): """Return base64 encoding of data.""" data = if not isinstance(, bytes) else return base64.b64encode(data) @property def stream(self): """Return stream object.""" from io import FileIO if getattr(self, '_stream', None) and not self._stream.closed: self._stream.close() self._stream = FileIO(self.file, mode='r', closefd=True) return self._stream @property def mem(self): """Return memory object.""" raise NotImplementedError @property def url(self): """Return url to file.""" import pathlib return pathlib.PurePosixPath(self.file).as_uri() def _openmode(self, data=None): openmode = 'r' if not PY2: # in Python 3 we need to open binary files in binary mode. checked = False if hasattr(self, 'data_format'): if self.data_format.encoding == 'base64': # binary, when the data is to be encoded to base64 openmode += 'b' checked = True elif 'text/' in self.data_format.mime_type: # not binary, when mime_type is 'text/' checked = True # when we can't guess it from the mime_type, we need to check the file. # mimetypes like application/xml and application/json are text files too. if not checked and not _is_textfile(self.file): openmode += 'b' return openmode class DataHandler(FileHandler): prop = 'data' def _openmode(self, data=None): openmode = 'w' if not PY2 and isinstance(data, bytes): # on Python 3 open the file in binary mode if the source is # bytes, which happens when the data was base64-decoded openmode += 'b' return openmode @property def data(self): """Return data.""" return getattr(self, '_data', None) @data.setter def data(self, value): self._reset_cache() self._data = value self._check_valid() @property def file(self): """Return file name storing the data. Requesting the file attributes writes the data to a temporary file on disk. """ if self._file is None: self._file = self._build_file_name() with open(self._file, self._openmode( as fh: fh.write( return self._file @property def stream(self): """Return a stream representation of the data.""" if not PY2 and isinstance(, bytes): return BytesIO( else: return StringIO(text_type( class StreamHandler(DataHandler): prop = 'stream' @property def stream(self): """Return the stream.""" return self._stream @stream.setter def stream(self, value): """Set the stream.""" self._reset_cache() self._stream = value self._check_valid() @property def data(self): """Return the data from the stream.""" if self._data is None: self._data = return self._data class UrlHandler(FileHandler): prop = 'url' @property def url(self): """Return the URL.""" return self._url @url.setter def url(self, value): """Set the URL value.""" self._reset_cache() self._url = value self._check_valid() @property def file(self): if self._file is not None: return self._file self._file = self._build_file_name(href=self.url) max_byte_size = self.max_input_size() # Create request try: reference_file = self._openurl(self.url, self.post_data) data_size = reference_file.headers.get('Content-Length', 0) except Exception as e: raise NoApplicableCode('File reference error: {}'.format(e)) error_message = 'File size for input "{}" exceeded. Maximum allowed: {} megabytes'.format( self.inpt.get('identifier', '?'), max_byte_size) if int(data_size) > int(max_byte_size): raise FileSizeExceeded(error_message) try: with open(self._file, 'wb') as f: data_size = 0 for chunk in reference_file.iter_content(chunk_size=1024): data_size += len(chunk) if int(data_size) > int(max_byte_size): raise FileSizeExceeded(error_message) f.write(chunk) except Exception as e: raise NoApplicableCode(e) return self._file @property def post_data(self): return self._post_data @post_data.setter def post_data(self, value): self._post_data = value @staticmethod def _openurl(href, data=None): """Open given href. """ LOGGER.debug('Fetching URL {}'.format(href)) if data is not None: req =, data=data, stream=True) else: req = requests.get(url=href, stream=True) return req @staticmethod def max_input_size(): """Calculates maximal size for input file based on configuration and units. :return: maximum file size in bytes """ ms = config.get_config_value('server', 'maxsingleinputsize') return config.get_size_mb(ms) * 1024**2 class SimpleHandler(DataHandler): """Data handler for Literal In- and Outputs >>> class Int_type(object): ... @staticmethod ... def convert(value): return int(value) >>> >>> class MyValidator(object): ... @staticmethod ... def validate(inpt): return 0 < < 3 >>> >>> inpt = SimpleHandler(data_type = Int_type) >>> inpt.validator = MyValidator >>> >>> = 1 >>> inpt.validator.validate(inpt) True >>> = 5 >>> inpt.validator.validate(inpt) False """ def __init__(self, workdir=None, data_type=None, mode=MODE.NONE): DataHandler.__init__(self, workdir=workdir, mode=mode) if data_type not in LITERAL_DATA_TYPES: raise ValueError('data_type {} not in {}'.format(data_type, LITERAL_DATA_TYPES)) self.data_type = data_type def data(self, value): """Set data value. Inputs are converted into target format. """ if self.data_type and value is not None: value = convert(self.data_type, value), value) class BasicIO: """Basic Input/Output class """ def __init__(self, identifier, title=None, abstract=None, keywords=None, min_occurs=1, max_occurs=1, metadata=[]): self.identifier = identifier self.title = title self.abstract = abstract self.keywords = keywords self.min_occurs = int(min_occurs) self.max_occurs = int(max_occurs) self.metadata = metadata class BasicLiteral: """Basic literal Input/Output class """ def __init__(self, data_type="integer", uoms=None): assert data_type in LITERAL_DATA_TYPES self.data_type = data_type # list of uoms self.uoms = [] # current uom self._uom = None # add all uoms (upcasting to UOM) if uoms is not None: for uom in uoms: if not isinstance(uom, UOM): uom = UOM(uom) self.uoms.append(uom) if self.uoms: # default/current uom self.uom = self.uoms[0] @property def uom(self): return self._uom @uom.setter def uom(self, uom): if uom is not None: self._uom = uom class BasicComplex(object): """Basic complex input/output class """ def __init__(self, data_format=None, supported_formats=None): self._data_format = data_format self._supported_formats = () if supported_formats: self.supported_formats = supported_formats if data_format: self.data_format = data_format elif self.supported_formats: # not an empty list, set the default/current format to the first self.data_format = supported_formats[0] def get_format(self, mime_type): """ :param mime_type: given mimetype :return: Format """ for frmt in self.supported_formats: if frmt.mime_type == mime_type: return frmt else: return None @property def validator(self): """Return the proper validator for given data_format """ return self.data_format.validate @property def supported_formats(self): return self._supported_formats @supported_formats.setter def supported_formats(self, supported_formats): """Setter of supported formats """ def set_format_validator(supported_format): if not supported_format.validate or \ supported_format.validate == emptyvalidator: supported_format.validate =\ get_validator(supported_format.mime_type) return supported_format self._supported_formats = tuple(map(set_format_validator, supported_formats)) @property def data_format(self): return self._data_format @data_format.setter def data_format(self, data_format): """self data_format setter """ if self._is_supported(data_format): self._data_format = data_format if not data_format.validate or data_format.validate == emptyvalidator: data_format.validate = get_validator(data_format.mime_type) else: raise InvalidParameterValue("Requested format {}, {}, {} not supported".format( data_format.mime_type, data_format.encoding, data_format.schema), 'mimeType') def _is_supported(self, data_format): if self.supported_formats: for frmt in self.supported_formats: if frmt.same_as(data_format): return True return False class BasicBoundingBox(object): """Basic BoundingBox input/output class """ def __init__(self, crss=None, dimensions=2): self.crss = crss or ['epsg:4326'] = self.crss[0] self.dimensions = dimensions self.ll = [] self.ur = [] class LiteralInput(BasicIO, BasicLiteral, SimpleHandler): """LiteralInput input abstract class """ def __init__(self, identifier, title=None, abstract=None, keywords=None, data_type="integer", workdir=None, allowed_values=None, uoms=None, mode=MODE.NONE, min_occurs=1, max_occurs=1, metadata=[], default=None, default_type=SOURCE_TYPE.DATA): BasicIO.__init__(self, identifier, title, abstract, keywords, min_occurs, max_occurs, metadata) BasicLiteral.__init__(self, data_type, uoms) SimpleHandler.__init__(self, workdir, data_type, mode=mode) if default_type != SOURCE_TYPE.DATA: raise InvalidParameterValue("Source types other than data are not supported.") self.any_value = False self.values_reference = None self.allowed_values = [] if allowed_values: if not isinstance(allowed_values, (tuple, list)): allowed_values = [allowed_values] self.any_value = any(is_anyvalue(a) for a in allowed_values) for value in allowed_values: if is_values_reference(value): self.values_reference = value break self.allowed_values = make_allowedvalues(allowed_values) self._default = default self._default_type = default_type if default is not None: = default @property def validator(self): """Get validator for any value as well as allowed_values :rtype: function """ if self.any_value: return validate_anyvalue elif self.values_reference: return validate_values_reference elif self.allowed_values: return validate_allowed_values else: return validate_value class LiteralOutput(BasicIO, BasicLiteral, SimpleHandler): """Basic LiteralOutput class """ def __init__(self, identifier, title=None, abstract=None, keywords=None, data_type=None, workdir=None, uoms=None, validate=None, mode=MODE.NONE): BasicIO.__init__(self, identifier, title, abstract, keywords) BasicLiteral.__init__(self, data_type, uoms) SimpleHandler.__init__(self, workdir=None, data_type=data_type, mode=mode) self._storage = None @property def storage(self): return self._storage @storage.setter def storage(self, storage): self._storage = storage @property def validator(self): """Get validator for any value as well as allowed_values """ return validate_anyvalue class BBoxInput(BasicIO, BasicBoundingBox, DataHandler): """Basic Bounding box input abstract class """ def __init__(self, identifier, title=None, abstract=None, keywords=[], crss=None, dimensions=None, workdir=None, mode=MODE.SIMPLE, min_occurs=1, max_occurs=1, metadata=[], default=None, default_type=SOURCE_TYPE.DATA): BasicIO.__init__(self, identifier, title, abstract, keywords, min_occurs, max_occurs, metadata) BasicBoundingBox.__init__(self, crss, dimensions) DataHandler.__init__(self, workdir=workdir, mode=mode) if default_type != SOURCE_TYPE.DATA: raise InvalidParameterValue("Source types other than data are not supported.") self._default = default self._default_type = default_type self._set_default_value(default, default_type) class BBoxOutput(BasicIO, BasicBoundingBox, DataHandler): """Basic BoundingBox output class """ def __init__(self, identifier, title=None, abstract=None, keywords=None, crss=None, dimensions=None, workdir=None, mode=MODE.NONE): BasicIO.__init__(self, identifier, title, abstract, keywords) BasicBoundingBox.__init__(self, crss, dimensions) DataHandler.__init__(self, workdir=workdir, mode=mode) self._storage = None @property def storage(self): return self._storage @storage.setter def storage(self, storage): self._storage = storage class ComplexInput(BasicIO, BasicComplex, IOHandler): """Complex input abstract class >>> ci = ComplexInput() >>> ci.validator = 1 >>> ci.validator 1 """ def __init__(self, identifier, title=None, abstract=None, keywords=None, workdir=None, data_format=None, supported_formats=None, mode=MODE.NONE, min_occurs=1, max_occurs=1, metadata=[], default=None, default_type=SOURCE_TYPE.DATA): BasicIO.__init__(self, identifier, title, abstract, keywords, min_occurs, max_occurs, metadata) IOHandler.__init__(self, workdir=workdir, mode=mode) BasicComplex.__init__(self, data_format, supported_formats) self._default = default self._default_type = default_type def file_handler(self, inpt): """<wps:Reference /> handler. Used when href is a file url.""" extend_instance(self, FileHandler) # check if file url is allowed self._validate_file_input(href=inpt.get('href')) # save the file reference input in workdir tmp_file = self._build_file_name(href=inpt.get('href')) try: inpt_file = urlparse(inpt.get('href')).path inpt_file = os.path.abspath(inpt_file) os.symlink(inpt_file, tmp_file) LOGGER.debug("Linked input file {} to {}.".format(inpt_file, tmp_file)) except Exception: # TODO: handle os.symlink on windows # raise NoApplicableCode("Could not link file reference: {}".format(e)) LOGGER.warn("Could not link file reference") shutil.copy2(inpt_file, tmp_file) return tmp_file def url_handler(self, inpt): # That could possibly go into the data property... if inpt.get('method') == 'POST': if 'body' in inpt: self.post_data = inpt.get('body') elif 'bodyreference' in inpt: self.post_data = requests.get(url=inpt.get('bodyreference')).text else: raise AttributeError("Missing post data content.") return inpt.get('href') def process(self, inpt): """Subclass with the appropriate handler given the data input.""" href = inpt.get('href', None) self.inpt = inpt if href: if urlparse(href).scheme == 'file': self.file = self.file_handler(inpt) else: # No file download occurs here. The file content will # only be retrieved when the file property is accessed. self.url = self.url_handler(inpt) else: = inpt.get('data') @staticmethod def _validate_file_input(href): href = href or '' parsed_url = urlparse(href) if parsed_url.scheme != 'file': raise FileURLNotSupported('Invalid URL scheme') file_path = parsed_url.path if not file_path: raise FileURLNotSupported('Invalid URL path') file_path = os.path.abspath(file_path) # build allowed paths list inputpaths = config.get_config_value('server', 'allowedinputpaths') allowed_paths = [os.path.abspath(p.strip()) for p in inputpaths.split(':') if p.strip()] for allowed_path in allowed_paths: if file_path.startswith(allowed_path): LOGGER.debug("Accepted file url as input.") return raise FileURLNotSupported() class ComplexOutput(BasicIO, BasicComplex, IOHandler): """Complex output abstract class >>> # temporary configuration >>> import ConfigParser >>> from import * >>> config = ConfigParser.RawConfigParser() >>> config.add_section('FileStorage') >>> config.set('FileStorage', 'target', './') >>> config.add_section('server') >>> config.set('server', 'outputurl', 'http://foo/bar/filestorage') >>> >>> # create temporary file >>> tiff_file = open('file.tiff', 'w') >>> tiff_file.write("AA") >>> tiff_file.close() >>> >>> co = ComplexOutput() >>> co.file ='file.tiff' >>> fs = FileStorage(config) >>> = fs >>> >>> url = co.url # get url, data are stored >>> >>> # get data - nothing is stored 'AA' """ def __init__(self, identifier, title=None, abstract=None, keywords=None, workdir=None, data_format=None, supported_formats=None, mode=MODE.NONE): BasicIO.__init__(self, identifier, title, abstract, keywords) IOHandler.__init__(self, workdir=workdir, mode=mode) BasicComplex.__init__(self, data_format, supported_formats) self._storage = None @property def storage(self): return self._storage @storage.setter def storage(self, storage): # don't set storage twice if self._storage is None: self._storage = storage # TODO: refactor ? def get_url(self): """Return URL pointing to data """ (outtype, storage, url) = return url if __name__ == "__main__": import doctest from pywps.wpsserver import temp_dir with temp_dir() as tmp: os.chdir(tmp) doctest.testmod()