3.x Series — IPython 5.3.0 documentation

# 3.x Series

## IPython 3.2.3

Fixes compatibility with Python 3.4.4.

## IPython 3.2.2

Address vulnerabilities when files have maliciously crafted filenames (CVE-2015-6938), or vulnerability when opening text files with malicious binary content (CVE pending).

Users are strongly encouraged to upgrade immediately. There are also a few small unicode and nbconvert-related fixes.

## IPython 3.2.1

IPython 3.2.1 is a small bugfix release, primarily for cross-site security fixes in the notebook. Users are strongly encouraged to upgrade immediately. There are also a few small unicode and nbconvert-related fixes.

See Issues closed in the 3.x development cycle for details.

## IPython 3.2

IPython 3.2 contains important security fixes. Users are strongly encouraged to upgrade immediately.

Highlights:

- Address cross-site scripting vulnerabilities CVE-2015-4706, CVE-2015-4707
- A security improvement that set the secure attribute to login cookie to prevent them to be sent over http
- Revert the face color of matplotlib axes in the inline backend to not be transparent.
- Enable mathjax safe mode by default
- Fix XSS vulnerability in JSON error messages
- Various widget-related fixes

See Issues closed in the 3.x development cycle for details.

## IPython 3.1

Released April 3, 2015

The first 3.x bugfix release, with 33 contributors and 344 commits. This primarily includes bugfixes to notebook layout and focus problems.

Highlights:

- Various focus jumping and scrolling fixes in the notebook.
- Various message ordering and widget fixes in the notebook.
- Images in markdown and output are confined to the notebook width. An `.unconfined` CSS class is added to disable this behavior per-image. The resize handle on output images is removed.
- Improved ordering of tooltip content for Python functions, putting the signature at the top.
- Fix UnicodeErrors when displaying some objects with unicode reprs on Python 2.
- Set the kernel’s working directory to the notebook directory when running `nbconvert --execute`, so that behavior matches the live notebook.
- Allow setting custom SSL options for the tornado server with `NotebookApp.ssl_options`, and protect against POODLE with default settings by disabling SSLv3.
- Fix memory leak in the IPython.parallel Controller on Python 3.

See Issues closed in the 3.x development cycle for details.

## Release 3.0

Released February 27, 2015

This is a really big release. Over 150 contributors, and almost 6000 commits in a bit under a year. Support for languages other than Python is greatly improved, notebook UI has been significantly redesigned, and a lot of improvement has happened in the experimental interactive widgets. The message protocol and document format have both been updated, while maintaining better compatibility with previous versions than prior updates. The notebook webapp now enables editing of any text file, and even a web-based terminal (on Unix platforms).

3.x will be the last monolithic release of IPython, as the next release cycle will see the growing project split into its Python-specific and language-agnostic components. Language-agnostic projects (notebook, qtconsole, etc.) will move under the umbrella of the new Project Jupyter name, while Python-specific projects (interactive Python shell, Python kernel, IPython.parallel) will remain under IPython, and be split into a few smaller packages. To reflect this, IPython is in a bit of a transition state. The logo on the notebook is now the Jupyter logo. When installing kernels system-wide, they go in a `jupyter` directory. We are going to do our best to ease this transition for users and developers.

Big changes are ahead.

### Using different kernels

You can now choose a kernel for a notebook within the user interface, rather than starting up a separate notebook server for each kernel you want to use. The syntax highlighting adapts to match the language you’re working in.

Information about the kernel is stored in the notebook file, so when you open a notebook, it will automatically start the correct kernel.

It is also easier to use the Qt console and the terminal console with other kernels, using the –kernel flag:

    ipython qtconsole --kernel bash
    ipython console --kernel bash

    # To list available kernels
    ipython kernelspec list

Kernel authors should see kernelspecs for how to register their kernels with IPython so that these mechanisms work.

### Typing unicode identifiers

Complex expressions can be much cleaner when written with a wider choice of characters. Python 3 allows unicode identifiers, and IPython 3 makes it easier to type those, using a feature from Julia. Type a backslash followed by a LaTeX style short name, such as `\alpha`. Press tab, and it will turn into α.

### Widget migration guide

The widget framework has a lot of backwards incompatible changes. For information about migrating widget notebooks and custom widgets to 3.0 refer to the widget migration guide.

### Other new features

- `TextWidget` and `TextareaWidget` objects now include a `placeholder` attribute, for displaying placeholder text before the user has typed anything.

- The `%load` magic can now find the source for objects in the user namespace. To enable searching the namespace, use the `-n` option.

      In [1]: %load -n my_module.some_function

- `DirectView` objects have a new `use_cloudpickle()` method, which works like `view.use_dill()`, but causes the `cloudpickle` module from PiCloud’s cloud library to be used rather than dill or the builtin pickle module.

- Added a .ipynb exporter to nbconvert. It can be used by passing `--to notebook` as a commandline argument to nbconvert.

- New nbconvert preprocessor called `ClearOutputPreprocessor`. This clears the output from IPython notebooks.

- New preprocessor for nbconvert that executes all the code cells in a notebook. To run a notebook and save its output in a new notebook:

      ipython nbconvert InputNotebook --ExecutePreprocessor.enabled=True --to notebook --output Executed

- Consecutive stream (stdout/stderr) output is merged into a single output in the notebook document. Previously, all output messages were preserved as separate output fields in the JSON. Now, the same merge is applied to the stored output as the displayed output, improving document load time for notebooks with many small outputs.

- `NotebookApp.webapp_settings` is deprecated and replaced with the more informatively named `NotebookApp.tornado_settings`.

- Using `%timeit` prints warnings if there is atleast a 4x difference in timings between the slowest and fastest runs, since this might meant that the multiple runs are not independent of one another.

- It’s now possible to provide mechanisms to integrate IPython with other event loops, in addition to the ones we already support. This lets you run GUI code in IPython with an interactive prompt, and to embed the IPython kernel in GUI applications. See Integrating with GUI event loops for details. As part of this, the direct `enable_*` and `disable_*` functions for various GUIs in `IPython.lib.inputhook` have been deprecated in favour of `enable_gui()` and `disable_gui()`.

- A `ScrollManager` was added to the notebook. The `ScrollManager` controls how the notebook document is scrolled using keyboard. Users can inherit from the `ScrollManager` or `TargetScrollManager` to customize how their notebook scrolls. The default `ScrollManager` is the `SlideScrollManager`, which tries to scroll to the nearest slide or sub-slide cell.

- The function `interact_manual()` has been added which behaves similarly to `interact()`, but adds a button to explicitly run the interacted-with function, rather than doing it automatically for every change of the parameter widgets. This should be useful for long-running functions.

- The `%cython` magic is now part of the Cython module. Use `%load_ext Cython` with a version of Cython >= 0.21 to have access to the magic now.

- The Notebook application now offers integrated terminals on Unix platforms, intended for when it is used on a remote server. To enable these, install the `terminado` Python package.

- The Notebook application can now edit any plain text files, via a full-page CodeMirror instance.

- Setting the default highlighting language for nbconvert with the config option `NbConvertBase.default_language` is deprecated. Nbconvert now respects metadata stored in the kernel spec.

- IPython can now be configured systemwide, with files in `/etc/ipython` or `/usr/local/etc/ipython` on Unix systems, or `%PROGRAMDATA%\ipython` on Windows.

- Added support for configurable user-supplied Jinja HTML templates for the notebook. Paths to directories containing template files can be specified via `NotebookApp.extra_template_paths`. User-supplied template directories searched first by the notebook, making it possible to replace existing templates with your own files.

  For example, to replace the notebook’s built-in `error.html` with your own, create a directory like `/home/my_templates` and put your override template at `/home/my_templates/error.html`. To start the notebook with your custom error page enabled, you would run:

      ipython notebook '--extra_template_paths=["/home/my_templates/"]'

  It’s also possible to override a template while also inheriting from that template, by prepending `templates/` to the `{% extends %}` target of your child template. This is useful when you only want to override a specific block of a template. For example, to add additional CSS to the built-in `error.html`, you might create an override that looks like:

      {% extends "templates/error.html" %}

      {% block stylesheet %}
      {{super()}}
      <style type="text/css">
        /* My Awesome CSS */
      </style>
      {% endblock %}

- Added a widget persistence API. This allows you to persist your notebooks interactive widgets. Two levels of control are provided: 1. Higher level- `WidgetManager.set_state_callbacks` allows you to register callbacks for loading and saving widget state. The callbacks you register are automatically called when necessary. 2. Lower level- the `WidgetManager` Javascript class now has `get_state` and `set_state` methods that allow you to get and set the state of the widget runtime.

  Example code for persisting your widget state to session data:

      %%javascript
      require(['widgets/js/manager'], function(manager) {
          manager.WidgetManager.set_state_callbacks(function() { // Load
              return JSON.parse(sessionStorage.widgets_state || '{}');
          }, function(state) { // Save
              sessionStorage.widgets_state = JSON.stringify(state);
          });
      });

- Enhanced support for `%env` magic. As before, `%env` with no arguments displays all environment variables and values. Additionally, `%env` can be used to get or set individual environment variables. To display an individual value, use the `%env var` syntax. To set a value, use `env var val` or `env var=val`. Python value expansion using `$` works as usual.

### Backwards incompatible changes

- The message protocol has been updated from version 4 to version 5. Adapters are included, so IPython frontends can still talk to kernels that implement protocol version 4.

- The notebook format has been updated from version 3 to version 4. Read-only support for v4 notebooks has been backported to IPython 2.4. Notable changes:

  - heading cells are removed in favor or markdown headings
  - notebook outputs and output messages are more consistent with each other
  - use `IPython.nbformat.read()` and `write()` to read and write notebook files instead of the deprecated `IPython.nbformat.current` APIs.

  You can downgrade a notebook to v3 via `nbconvert`:

      ipython nbconvert --to notebook --nbformat 3 <notebook>

  which will create `notebook.v3.ipynb`, a copy of the notebook in v3 format.

- `IPython.core.oinspect.getsource()` call specification has changed:

  - `oname` keyword argument has been added for property source formatting
  - `is_binary` keyword argument has been dropped, passing `True` had previously short-circuited the function to return `None` unconditionally

- Removed the octavemagic extension: it is now available as `oct2py.ipython`.

- Creating PDFs with LaTeX no longer uses a post processor. Use `nbconvert --to pdf` instead of `nbconvert --to latex --post pdf`.

- Used https://github.com/jdfreder/bootstrap2to3 to migrate the Notebook to Bootstrap 3.

  Additional changes:

  - Set `.tab-content .row` `0px;` left and right margin (bootstrap default is `-15px;`)
  - Removed `height: @btn_mini_height;` from `.list_header>div, .list_item>div` in `tree.less`
  - Set `#header` div `margin-bottom: 0px;`
  - Set `#menus` to `float: left;`
  - Set `#maintoolbar .navbar-text` to `float: none;`
  - Added no-padding convenience class.
  - Set border of #maintoolbar to 0px

- Accessing the `container` DOM object when displaying javascript has been deprecated in IPython 2.0 in favor of accessing `element`. Starting with IPython 3.0 trying to access `container` will raise an error in browser javascript console.

- `IPython.utils.py3compat.open` was removed: `io.open()` provides all the same functionality.

- The NotebookManager and `/api/notebooks` service has been replaced by a more generic ContentsManager and `/api/contents` service, which supports all kinds of files.

- The Dashboard now lists all files, not just notebooks and directories.

- The `--script` hook for saving notebooks to Python scripts is removed, use `ipython nbconvert --to python notebook` instead.

- The `rmagic` extension is deprecated, as it is now part of rpy2. See `rpy2.ipython.rmagic`.

- `start_kernel()` and `format_kernel_cmd()` no longer accept a `executable` parameter. Use the kernelspec machinery instead.

- The widget classes have been renamed from `*Widget` to `*`. The old names are still functional, but are deprecated. i.e. `IntSliderWidget` has been renamed to `IntSlider`.

- The ContainerWidget was renamed to Box and no longer defaults as a flexible box in the web browser. A new FlexBox widget was added, which allows you to use the flexible box model.

- The notebook now uses a single websocket at `/kernels/<kernel-id>/channels` instead of separate `/kernels/<kernel-id>/{shell|iopub|stdin}` channels. Messages on each channel are identified by a `channel` key in the message dict, for both send and recv.

#### Content Security Policy

The Content Security Policy is a web standard for adding a layer of security to detect and mitigate certain classes of attacks, including Cross Site Scripting (XSS) and data injection attacks. This was introduced into the notebook to ensure that the IPython Notebook and its APIs (by default) can only be embedded in an iframe on the same origin.

Override `headers['Content-Security-Policy']` within your notebook configuration to extend for alternate domains and security settings.:

    c.NotebookApp.tornado_settings = {
        'headers': {
            'Content-Security-Policy': "frame-ancestors 'self'"
        }
    }

Example policies:

    Content-Security-Policy: default-src 'self' https://*.jupyter.org

Matches embeddings on any subdomain of jupyter.org, so long as they are served over SSL.

There is a report-uri endpoint available for logging CSP violations, located at `/api/security/csp-report`. To use it, set `report-uri` as part of the CSP:

    c.NotebookApp.tornado_settings = {
        'headers': {
            'Content-Security-Policy': "frame-ancestors 'self'; report-uri /api/security/csp-report"
        }
    }

It simply provides the CSP report as a warning in IPython’s logs. The default CSP sets this report-uri relative to the `base_url` (not shown above).

For a more thorough and accurate guide on Content Security Policies, check out MDN’s Using Content Security Policy for more examples.