# -*- coding: utf-8 -*- """Top-level display functions for displaying object in different formats. Authors: * Brian Granger """ #----------------------------------------------------------------------------- # Copyright (C) 2013 The IPython Development Team # # Distributed under the terms of the BSD License. The full license is in # the file COPYING, distributed as part of this software. #----------------------------------------------------------------------------- #----------------------------------------------------------------------------- # Imports #----------------------------------------------------------------------------- from __future__ import print_function import os import struct from IPython.utils.py3compat import (string_types, cast_bytes_py2, cast_unicode, unicode_type) from .displaypub import publish_display_data #----------------------------------------------------------------------------- # utility functions #----------------------------------------------------------------------------- def _safe_exists(path): """Check path, but don't let exceptions raise""" try: return os.path.exists(path) except Exception: return False def _merge(d1, d2): """Like update, but merges sub-dicts instead of clobbering at the top level. Updates d1 in-place """ if not isinstance(d2, dict) or not isinstance(d1, dict): return d2 for key, value in d2.items(): d1[key] = _merge(d1.get(key), value) return d1 def _display_mimetype(mimetype, objs, raw=False, metadata=None): """internal implementation of all display_foo methods Parameters ---------- mimetype : str The mimetype to be published (e.g. 'image/png') objs : tuple of objects The Python objects to display, or if raw=True raw text data to display. raw : bool Are the data objects raw data or Python objects that need to be formatted before display? [default: False] metadata : dict (optional) Metadata to be associated with the specific mimetype output. """ if metadata: metadata = {mimetype: metadata} if raw: # turn list of pngdata into list of { 'image/png': pngdata } objs = [ {mimetype: obj} for obj in objs ] display(*objs, raw=raw, metadata=metadata, include=[mimetype]) #----------------------------------------------------------------------------- # Main functions #----------------------------------------------------------------------------- def display(*objs, **kwargs): """Display a Python object in all frontends. By default all representations will be computed and sent to the frontends. Frontends can decide which representation is used and how. Parameters ---------- objs : tuple of objects The Python objects to display. raw : bool, optional Are the objects to be displayed already mimetype-keyed dicts of raw display data, or Python objects that need to be formatted before display? [default: False] include : list or tuple, optional A list of format type strings (MIME types) to include in the format data dict. If this is set *only* the format types included in this list will be computed. exclude : list or tuple, optional A list of format type strings (MIME types) to exclude in the format data dict. If this is set all format types will be computed, except for those included in this argument. metadata : dict, optional A dictionary of metadata to associate with the output. mime-type keys in this dictionary will be associated with the individual representation formats, if they exist. """ raw = kwargs.get('raw', False) include = kwargs.get('include') exclude = kwargs.get('exclude') metadata = kwargs.get('metadata') from IPython.core.interactiveshell import InteractiveShell if not raw: format = InteractiveShell.instance().display_formatter.format for obj in objs: # If _ipython_display_ is defined, use that to display this object. If # it returns NotImplemented, use the _repr_ logic (default). if not hasattr(obj, '_ipython_display_') or obj._ipython_display_(**kwargs) is NotImplemented: if raw: publish_display_data('display', obj, metadata) else: format_dict, md_dict = format(obj, include=include, exclude=exclude) if metadata: # kwarg-specified metadata gets precedence _merge(md_dict, metadata) publish_display_data('display', format_dict, md_dict) def display_pretty(*objs, **kwargs): """Display the pretty (default) representation of an object. Parameters ---------- objs : tuple of objects The Python objects to display, or if raw=True raw text data to display. raw : bool Are the data objects raw data or Python objects that need to be formatted before display? [default: False] metadata : dict (optional) Metadata to be associated with the specific mimetype output. """ _display_mimetype('text/plain', objs, **kwargs) def display_html(*objs, **kwargs): """Display the HTML representation of an object. Parameters ---------- objs : tuple of objects The Python objects to display, or if raw=True raw HTML data to display. raw : bool Are the data objects raw data or Python objects that need to be formatted before display? [default: False] metadata : dict (optional) Metadata to be associated with the specific mimetype output. """ _display_mimetype('text/html', objs, **kwargs) def display_svg(*objs, **kwargs): """Display the SVG representation of an object. Parameters ---------- objs : tuple of objects The Python objects to display, or if raw=True raw svg data to display. raw : bool Are the data objects raw data or Python objects that need to be formatted before display? [default: False] metadata : dict (optional) Metadata to be associated with the specific mimetype output. """ _display_mimetype('image/svg+xml', objs, **kwargs) def display_png(*objs, **kwargs): """Display the PNG representation of an object. Parameters ---------- objs : tuple of objects The Python objects to display, or if raw=True raw png data to display. raw : bool Are the data objects raw data or Python objects that need to be formatted before display? [default: False] metadata : dict (optional) Metadata to be associated with the specific mimetype output. """ _display_mimetype('image/png', objs, **kwargs) def display_jpeg(*objs, **kwargs): """Display the JPEG representation of an object. Parameters ---------- objs : tuple of objects The Python objects to display, or if raw=True raw JPEG data to display. raw : bool Are the data objects raw data or Python objects that need to be formatted before display? [default: False] metadata : dict (optional) Metadata to be associated with the specific mimetype output. """ _display_mimetype('image/jpeg', objs, **kwargs) def display_latex(*objs, **kwargs): """Display the LaTeX representation of an object. Parameters ---------- objs : tuple of objects The Python objects to display, or if raw=True raw latex data to display. raw : bool Are the data objects raw data or Python objects that need to be formatted before display? [default: False] metadata : dict (optional) Metadata to be associated with the specific mimetype output. """ _display_mimetype('text/latex', objs, **kwargs) def display_json(*objs, **kwargs): """Display the JSON representation of an object. Note that not many frontends support displaying JSON. Parameters ---------- objs : tuple of objects The Python objects to display, or if raw=True raw json data to display. raw : bool Are the data objects raw data or Python objects that need to be formatted before display? [default: False] metadata : dict (optional) Metadata to be associated with the specific mimetype output. """ _display_mimetype('application/json', objs, **kwargs) def display_javascript(*objs, **kwargs): """Display the Javascript representation of an object. Parameters ---------- objs : tuple of objects The Python objects to display, or if raw=True raw javascript data to display. raw : bool Are the data objects raw data or Python objects that need to be formatted before display? [default: False] metadata : dict (optional) Metadata to be associated with the specific mimetype output. """ _display_mimetype('application/javascript', objs, **kwargs) #----------------------------------------------------------------------------- # Smart classes #----------------------------------------------------------------------------- class DisplayObject(object): """An object that wraps data to be displayed.""" _read_flags = 'r' def __init__(self, data=None, url=None, filename=None): """Create a display object given raw data. When this object is returned by an expression or passed to the display function, it will result in the data being displayed in the frontend. The MIME type of the data should match the subclasses used, so the Png subclass should be used for 'image/png' data. If the data is a URL, the data will first be downloaded and then displayed. If Parameters ---------- data : unicode, str or bytes The raw data or a URL or file to load the data from url : unicode A URL to download the data from. filename : unicode Path to a local file to load the data from. """ if data is not None and isinstance(data, string_types): if data.startswith('http') and url is None: url = data filename = None data = None elif _safe_exists(data) and filename is None: url = None filename = data data = None self.data = data self.url = url self.filename = None if filename is None else unicode_type(filename) self.reload() self._check_data() def _check_data(self): """Override in subclasses if there's something to check.""" pass def reload(self): """Reload the raw data from file or URL.""" if self.filename is not None: with open(self.filename, self._read_flags) as f: self.data = f.read() elif self.url is not None: try: try: from urllib.request import urlopen # Py3 except ImportError: from urllib2 import urlopen response = urlopen(self.url) self.data = response.read() # extract encoding from header, if there is one: encoding = None for sub in response.headers['content-type'].split(';'): sub = sub.strip() if sub.startswith('charset'): encoding = sub.split('=')[-1].strip() break # decode data, if an encoding was specified if encoding: self.data = self.data.decode(encoding, 'replace') except: self.data = None class TextDisplayObject(DisplayObject): """Validate that display data is text""" def _check_data(self): if self.data is not None and not isinstance(self.data, string_types): raise TypeError("%s expects text, not %r" % (self.__class__.__name__, self.data)) class Pretty(TextDisplayObject): def _repr_pretty_(self): return self.data class HTML(TextDisplayObject): def _repr_html_(self): return self.data def __html__(self): """ This method exists to inform other HTML-using modules (e.g. Markupsafe, htmltag, etc) that this object is HTML and does not need things like special characters (<>&) escaped. """ return self._repr_html_() class Math(TextDisplayObject): def _repr_latex_(self): s = self.data.strip('$') return "$$%s$$" % s class Latex(TextDisplayObject): def _repr_latex_(self): return self.data class SVG(DisplayObject): # wrap data in a property, which extracts the tag, discarding # document headers _data = None @property def data(self): return self._data @data.setter def data(self, svg): if svg is None: self._data = None return # parse into dom object from xml.dom import minidom svg = cast_bytes_py2(svg) x = minidom.parseString(svg) # get svg tag (should be 1) found_svg = x.getElementsByTagName('svg') if found_svg: svg = found_svg[0].toxml() else: # fallback on the input, trust the user # but this is probably an error. pass svg = cast_unicode(svg) self._data = svg def _repr_svg_(self): return self.data class JSON(TextDisplayObject): def _repr_json_(self): return self.data css_t = """$("head").append($("").attr({ rel: "stylesheet", type: "text/css", href: "%s" })); """ lib_t1 = """$.getScript("%s", function () { """ lib_t2 = """}); """ class Javascript(TextDisplayObject): def __init__(self, data=None, url=None, filename=None, lib=None, css=None): """Create a Javascript display object given raw data. When this object is returned by an expression or passed to the display function, it will result in the data being displayed in the frontend. If the data is a URL, the data will first be downloaded and then displayed. In the Notebook, the containing element will be available as `element`, and jQuery will be available. The output area starts hidden, so if the js appends content to `element` that should be visible, then it must call `container.show()` to unhide the area. Parameters ---------- data : unicode, str or bytes The Javascript source code or a URL to download it from. url : unicode A URL to download the data from. filename : unicode Path to a local file to load the data from. lib : list or str A sequence of Javascript library URLs to load asynchronously before running the source code. The full URLs of the libraries should be given. A single Javascript library URL can also be given as a string. css: : list or str A sequence of css files to load before running the source code. The full URLs of the css files should be given. A single css URL can also be given as a string. """ if isinstance(lib, string_types): lib = [lib] elif lib is None: lib = [] if isinstance(css, string_types): css = [css] elif css is None: css = [] if not isinstance(lib, (list,tuple)): raise TypeError('expected sequence, got: %r' % lib) if not isinstance(css, (list,tuple)): raise TypeError('expected sequence, got: %r' % css) self.lib = lib self.css = css super(Javascript, self).__init__(data=data, url=url, filename=filename) def _repr_javascript_(self): r = '' for c in self.css: r += css_t % c for l in self.lib: r += lib_t1 % l r += self.data r += lib_t2*len(self.lib) return r # constants for identifying png/jpeg data _PNG = b'\x89PNG\r\n\x1a\n' _JPEG = b'\xff\xd8' def _pngxy(data): """read the (width, height) from a PNG header""" ihdr = data.index(b'IHDR') # next 8 bytes are width/height w4h4 = data[ihdr+4:ihdr+12] return struct.unpack('>ii', w4h4) def _jpegxy(data): """read the (width, height) from a JPEG header""" # adapted from http://www.64lines.com/jpeg-width-height idx = 4 while True: block_size = struct.unpack('>H', data[idx:idx+2])[0] idx = idx + block_size if data[idx:idx+2] == b'\xFF\xC0': # found Start of Frame iSOF = idx break else: # read another block idx += 2 h, w = struct.unpack('>HH', data[iSOF+5:iSOF+9]) return w, h class Image(DisplayObject): _read_flags = 'rb' _FMT_JPEG = u'jpeg' _FMT_PNG = u'png' _ACCEPTABLE_EMBEDDINGS = [_FMT_JPEG, _FMT_PNG] def __init__(self, data=None, url=None, filename=None, format=u'png', embed=None, width=None, height=None, retina=False): """Create a PNG/JPEG image object given raw data. When this object is returned by an input cell or passed to the display function, it will result in the image being displayed in the frontend. Parameters ---------- data : unicode, str or bytes The raw image data or a URL or filename to load the data from. This always results in embedded image data. url : unicode A URL to download the data from. If you specify `url=`, the image data will not be embedded unless you also specify `embed=True`. filename : unicode Path to a local file to load the data from. Images from a file are always embedded. format : unicode The format of the image data (png/jpeg/jpg). If a filename or URL is given for format will be inferred from the filename extension. embed : bool Should the image data be embedded using a data URI (True) or be loaded using an tag. Set this to True if you want the image to be viewable later with no internet connection in the notebook. Default is `True`, unless the keyword argument `url` is set, then default value is `False`. Note that QtConsole is not able to display images if `embed` is set to `False` width : int Width to which to constrain the image in html height : int Height to which to constrain the image in html retina : bool Automatically set the width and height to half of the measured width and height. This only works for embedded images because it reads the width/height from image data. For non-embedded images, you can just set the desired display width and height directly. Examples -------- # embedded image data, works in qtconsole and notebook # when passed positionally, the first arg can be any of raw image data, # a URL, or a filename from which to load image data. # The result is always embedding image data for inline images. Image('http://www.google.fr/images/srpr/logo3w.png') Image('/path/to/image.jpg') Image(b'RAW_PNG_DATA...') # Specifying Image(url=...) does not embed the image data, # it only generates `` tag with a link to the source. # This will not work in the qtconsole or offline. Image(url='http://www.google.fr/images/srpr/logo3w.png') """ if filename is not None: ext = self._find_ext(filename) elif url is not None: ext = self._find_ext(url) elif data is None: raise ValueError("No image data found. Expecting filename, url, or data.") elif isinstance(data, string_types) and ( data.startswith('http') or _safe_exists(data) ): ext = self._find_ext(data) else: ext = None if ext is not None: format = ext.lower() if ext == u'jpg' or ext == u'jpeg': format = self._FMT_JPEG if ext == u'png': format = self._FMT_PNG elif isinstance(data, bytes) and format == 'png': # infer image type from image data header, # only if format might not have been specified. if data[:2] == _JPEG: format = 'jpeg' self.format = unicode_type(format).lower() self.embed = embed if embed is not None else (url is None) if self.embed and self.format not in self._ACCEPTABLE_EMBEDDINGS: raise ValueError("Cannot embed the '%s' image format" % (self.format)) self.width = width self.height = height self.retina = retina super(Image, self).__init__(data=data, url=url, filename=filename) if retina: self._retina_shape() def _retina_shape(self): """load pixel-doubled width and height from image data""" if not self.embed: return if self.format == 'png': w, h = _pngxy(self.data) elif self.format == 'jpeg': w, h = _jpegxy(self.data) else: # retina only supports png return self.width = w // 2 self.height = h // 2 def reload(self): """Reload the raw data from file or URL.""" if self.embed: super(Image,self).reload() if self.retina: self._retina_shape() def _repr_html_(self): if not self.embed: width = height = '' if self.width: width = ' width="%d"' % self.width if self.height: height = ' height="%d"' % self.height return u'' % (self.url, width, height) def _data_and_metadata(self): """shortcut for returning metadata with shape information, if defined""" md = {} if self.width: md['width'] = self.width if self.height: md['height'] = self.height if md: return self.data, md else: return self.data def _repr_png_(self): if self.embed and self.format == u'png': return self._data_and_metadata() def _repr_jpeg_(self): if self.embed and (self.format == u'jpeg' or self.format == u'jpg'): return self._data_and_metadata() def _find_ext(self, s): return unicode_type(s.split('.')[-1].lower()) def clear_output(wait=False): """Clear the output of the current cell receiving output. Parameters ---------- wait : bool [default: false] Wait to clear the output until new output is available to replace it.""" from IPython.core.interactiveshell import InteractiveShell if InteractiveShell.initialized(): InteractiveShell.instance().display_pub.clear_output(wait) else: from IPython.utils import io print('\033[2K\r', file=io.stdout, end='') io.stdout.flush() print('\033[2K\r', file=io.stderr, end='') io.stderr.flush()