.. _configuring-pywb:

Configuring the Web Archive
===========================

pywb offers an extensible YAML based configuration format via a main ``config.yaml`` at the root of each web archive.

.. _framed_vs_frameless:

Framed vs Frameless Replay
--------------------------

pywb supports several modes for serving archived web content.

With **framed replay**, the archived content is loaded into an iframe, and a top frame UI provides info and metadata.
In this mode, the top frame url is for example, ``http://my-archive.example.com/<coll name>/http://example.com/`` while
the actual content is served at ``http://my-archive.example.com/<coll name>/mp_/http://example.com/``


With **frameless replay**, the archived content is loaded directly, and a banner UI is injected into the page.

In this mode, the content is served directly at ``http://my-archive.example.com/<coll name>/http://example.com/``

For security reasons, we recommend running pywb in framed mode, because a malicious site
`could tamper with the banner <http://labs.rhizome.org/presentations/security.html#/13>`_

However, for certain situations, frameless replay made be appropriate.

To disable framed replay add:

``framed_replay: false`` to your config.yaml


Note: pywb also supports HTTP/S **proxy mode** which requires additional setup. See :ref:`https-proxy` for more details.


Directory Structure
-------------------

The pywb system is designed to automatically access and manage web archive collections that follow a defined directory structure.
The directory structure can be fully customized and "special" collections can be defined outside the structure as well.

The default directory structure for a web archive is as follows::


    +-- config.yaml (optional)
    |
    +-- templates (optional)
    |
    +-- static (optional)
    |
    +-- collections
        |
        +-- <coll name>
            |
            +-- archives
            |     |
            |     +-- (WARC or ARC files here)
            |
            +-- indexes
            |     |
            |     +-- (CDXJ index files here)
            | 
            +-- templates
            |     |
            |     +-- (optional html templates here)
            |
            +-- static
                  |
                  +-- (optional custom static assets here)
              

If running with default settings, the ``config.yaml`` can be omitted.

It is possible to config these directory paths in the config.yaml
The following are some of the implicit default settings which can be customized::

  collections_root: collections
  archive_paths: archive
  index_paths: indexes

(For a complete list of defaults, see the ``pywb/default_config.yaml`` file for reference)

Index Paths
^^^^^^^^^^^

The ``index_paths`` key defines the subdirectory for index files (usually CDXJ) and determine the contents of each archive collection.

The index files usually contain a pointer to a WARC file, but not the absolute path.

Archive Paths
^^^^^^^^^^^^^

The ``archive_paths`` key indicates how pywb will resolve WARC files listed in the index.

For example, it is possible to configure multiple archive paths::

  archive_paths:
    - archive
    - http://remote-bakup.example.com/collections/

When resolving a ``example.warc.gz``, pywb will then check (in order):

 * First, ``collections/<coll name>/example.warc.gz``
 * Then, ``http://remote-backup.example.com/collections/<coll name>/example.warc.gz`` (if first lookup unsuccessful)


UI Customizations
-----------------

pywb supports UI customizations, either for an entire archive,
or per-collection.

Static Files
^^^^^^^^^^^^

The replay server will automatically support static files placed under the following directories:

* Files under the root ``static`` directory can be accessed via ``http://my-archive.example.com/static/<filename>``

* Files under the per-collection ``./collections/<coll name>/static`` directory can be accessed via ``http://my-archive.example.com/static/_/<coll name>/<filename>``

Templates
^^^^^^^^^

pywb users Jinja2 templates to render HTML to render the HTML for all aspects of the application.
A version placed in the ``templates`` directory, either in the root or per collection, will override that template.

To copy the default pywb template to the template directory run:

``wb-manager template --add search_html``

The following templates are available:

 * ``home.html`` -- Home Page Template, used for ``http://my-archive.example.com/``

 * ``search.html`` -- Collection Template, used for each collection page ``http://my-archive.example.com/<coll name>/``

 * ``query.html`` -- Capture Query Page for a given url, used for ``http://my-archive.example.com/<coll name/*/<url>``

Error Pages:

 * ``not_found.html`` -- Page to show when a url is not found in the archive

 * ``error.html`` -- Generic Error Page for any error (except not found)

Replay and Banner templates:

 * ``frame_insert.html`` -- Top-frame for framed replay mode (not used with frameless mode)

 * ``head_insert.html`` -- Rewriting code injected into ``<head>`` of each replayed page. 
   This template includes the banner template and itself should generally not need to be modified.

 * ``banner.html`` -- The banner used for frameless replay. Can be set to blank to disable the banner.


Custom Outer Replay Frame
^^^^^^^^^^^^^^^^^^^^^^^^^

The top-frame used for framed replay can be replaced or augmented
by modifiying the ``frame_insert.html``.

To start with modifiying the default outer page, you can add it to the current
templates directory by running ``wb-manager template --add frame_insert_html``

To initialize the replay, the outer page should include ``wb_frame.js``,
create an ``<iframe>`` element and pass the id (or element itself) to the ``ContentFrame`` constructor:

.. code-block:: html

  <script src='{{ host_prefix }}/{{ static_path }}/wb_frame.js'> </script>
  <script>
  var cframe = new ContentFrame({"url": "{{ url }}" + window.location.hash,
                                 "prefix": "{{ wb_prefix }}",
                                 "request_ts": "{{ wb_url.timestamp }}",
                                 "iframe": "#replay_iframe"});
  </script>


The outer frame can receive notifications of changes to the replay via ``postMessage``

For example, to detect when the content frame changed and log the new url and timestamp,
use the following script to the outer frame html:

.. code-block:: javascript

  window.addEventListener("message", function(event) {
    if (event.data.wb_type == "load" || event.data.wb_type == "replace-url") {
      console.log("New Url: " + event.data.url);
      console.log("New Timestamp: " + event.data.ts);
    }
  });

The ``load`` message is sent when a new page is first loaded, while ``replace-url`` is used
for url changes caused by content frame History navigation.


Custom Defined Collections
--------------------------

While pywb can detect automatically collections following the above directory structure,
it may be useful to declare custom collections explicitly.

In addition, several "special" collection definitions are possible.

All custom defined collections are placed under the ``collections`` key in ``config.yaml``


.. _live-web:

Live Web Collection
^^^^^^^^^^^^^^^^^^^

The live web collection proxies all data to the live web, and can be defined as follows::

  collections:
    live: $live

This configures the ``/live/`` route to point to the live web.

(As a shortcut, ``wayback --live`` adds this collection via cli w/o modifiying the config.yaml)

This collection can be useful for testing, or even more powerful, when combined with recording.


.. _auto-all:

Auto "All" Aggregate Collection
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

The aggregate all collections automatically aggregates data from all collections in the ``collections`` directory::

  collections:
    all: $all

Accessing ``/all/<url>`` will cause an aggregate lookup within the collections directory.

Note: It is not (yet) possible to exclude collections from the auto-all collection, although "special" collections are not included.

Collection Provenance
"""""""""""""""""""""

When using the auto-all collection, it is possible to determine the original collection of each resource by looking at the ``Link`` header metadata
if :ref:`memento-api` is enabled. The header will include the extra ``collection`` field, specifying the collection::

  Link: <http://example.com/>; rel="original", <http://localhost:8080/all/mp_/http://example.com/>; rel="timegate", <http://localhost:8080/all/timemap/link/http://example.com/>; rel="timemap"; type="application/link-format", <http://localhost:8080/all/20170920185327mp_/http://example.com/>; rel="memento"; datetime="Wed, 20 Sep 2017 18:20:19 GMT"; collection="coll-1"


For example, if two collections ``coll-1`` and ``coll-2`` contain ``http://example.com/``, loading the timemap for
``/all/timemap/link/http://example.com/`` might look like as follows::

  <http://localhost:8080/all/timemap/link/http://example.com/>; rel="self"; type="application/link-format"; from="Wed, 20 Sep 2017 03:53:27 GMT",
  <http://localhost:8080/all/mp_/http://example.com/>; rel="timegate",
  <http://example.com/>; rel="original",
  <http://example.com/>; rel="memento"; datetime="Wed, 20 Sep 2017 03:53:27 GMT"; collection="coll-1",
  <http://example.com/>; rel="memento"; datetime="Wed, 20 Sep 2017 04:53:27 GMT"; collection="coll-2",

Identifiying the Collections
""""""""""""""""""""""""""""

When using the "all" collection, it is possible to determine the actual collection of each url by looking at the ``Link`` header metadata,
which in addition to memento relations, include the extra ``collection=`` field, specifying the collection::

  Link: <http://example.com/>; rel="original", <http://localhost:8080/all/mp_/http://example.com/>; rel="timegate", <http://localhost:8080/all/timemap/link/http://example.com/>; rel="timemap"; type="application/link-format", <http://localhost:8080/all/20170920185327mp_/http://example.com/>; rel="memento"; datetime="Wed, 20 Sep 2017 18:20:19 GMT"; collection="coll-1"


For example, if two collections ``coll-1`` and ``coll-2`` contain ``http://example.com/``, loading the timemap for
``/all/timemap/link/http://example.com/`` might look like as follows::

  <http://localhost:8080/all/timemap/link/http://example.com/>; rel="self"; type="application/link-format"; from="Wed, 20 Sep 2017 03:53:27 GMT",
  <http://localhost:8080/all/mp_/http://example.com/>; rel="timegate",
  <http://example.com/>; rel="original",
  <http://example.com/>; rel="memento"; datetime="Wed, 20 Sep 2017 03:53:27 GMT"; collection="coll-1",
  <http://example.com/>; rel="memento"; datetime="Wed, 20 Sep 2017 04:53:27 GMT"; collection="coll-2",


Generic Collection Definitions
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

The collection definition syntax allows for explicitly setting the index, archive paths
and all other templates, per collection, for example::

  collections:
    custom:
       index: ./path/to/indexes
       resource: ./some/other/path/to/archive/
       query_html: ./path/to/templates/query.html


If possible, it is recommended to use the default directory structure to avoid per-collection configuration.
However, this configuration allows for using pywb with existing collections that have unique path requirements.


Remote Memento Collection
^^^^^^^^^^^^^^^^^^^^^^^^^

It's also possible to define remote archives as easily as location collections.
For example, the following defines a collection ``/ia/`` which accesses
Internet Archive's Wayback Machine as a single collection::

  collections:
    ia: memento+https://web.archive.org/web/

Many additional options, including memento "aggregation", fallback chains are possible
using the Warcserver configuration syntax. See :ref:`warcserver-config` for more info.


Root Collection
^^^^^^^^^^^^^^^

It is also possible to define a "root" collection, for example, accessible at ``http://my-archive.example.com/<url>``
Such a collection must be defined explicitly using the ``$root`` as collection name::

  collections:
    $root:
       index: ./path/to/indexes
       resource: ./path/to/archive/

Note: When a root collection is set, no other collections are currently accessible, they are ignored.

.. _recording-mode:

Recording Mode
--------------

Recording mode enables pywb to support recording into any automatically managed collection, using
the ``/<coll>/record/<url>`` path. Accessing this path will result in pywb writing new WARCs directly into 
the collection ``<coll>``.

To enable recording from the live web, simply run ``wayback --record``.

To further customize recording mode, add the ``recorder`` block to the root of ``config.yaml``.

The command-line option is equivalent to adding ``recorder: live``.

The full set of configurable options (with their default settings) is as follows::

  recorder:
     source_coll: live
     rollover_size: 100000000
     rollover_idle_secs: 600
     filename_template: my-warc-{timestamp}-{hostname}-{random}.warc.gz


The required ``source_coll`` setting specifies the source collection from which to load content that will be recorded.
Most likely this will be the :ref:`live-web` collection, which should also be defined. 
However, it could be any other collection, allowing for "extraction" from other collections or remote web archives.
Both the request and response are recorded into the WARC file, and most standard HTTP verbs should be recordable.

The other options are optional and may be omitted. The ``rollover_size`` and ``rollover_idle_secs`` specified
the maximum size and maximum idle time, respectively, after which a new WARC file is created.
For example, a new WARC will be created if more than 100MB are recorded, or after 600 seconds have elapsed between
subsequent requests. This allows the WARC size to be more manageable and prevents files from being left open for long periods of time.

The ``filename-template`` specifies the naming convention for WARC files, and allows a timestamp, current hostname, and
random string to be inserted into the filename.

For example, if recording with the above config into a collection called ``my-coll``, the user would access:

``http://my-archive.example.com/my-coll/record/http://example.com/``, which would load ``http://example.com/`` from the live web
and write the request and response to a WARC named something like:

``./collections/my-coll/archive/my-warc-20170102030000000000-archive.example.com-QRTGER.warc.gz``

If running with auto indexing, the WARC will also get automatically indexd and available for replay after the index interval.

As a shortcut, ``recorder: live`` can also be used to specify only the ``source_coll`` option.


Auto-Indexing Mode
------------------

If auto-indexing is enabled, pywb will update the indexes stored in the ``indexes`` directory whenever files are added or modified in the
``archive`` directory. Auto-indexing can be enabled via the ``autoindex`` option set to the check interval in seconds::

  autoindex: 30

This specifies that the ``archive`` directories should be every 30 seconds. Auto-indexing is useful when WARCs are being
appened to or added to the ``archive`` by an extneral operation.

If a user is manually adding a new WARC to the collection, ``wb-manager add <coll> <path/to/warc>`` is recommended,
as this will add the WARC and perform a one-time reindex the collection, without the need for auto-indexing.

Note: Auto-indexing also does not support deletion of removal of WARCs from the ``archive`` directory.

This is not a common operation for web archives, a WARC must be manually removed from the 
``collections/<coll>/archive/`` directory and then collection index can be regenreated from the remaining WARCs
by running ``wb-manager reindex <coll>``

The auto-indexing mode can also be enabled via commandline by running ``wayback -a`` or ``wayback -a --auto-interval 30`` to also set the interval.

(If running pywb with uWSGI in multi-process mode, the auto-indexing is only run in a single worker to avoid race conditions and duplicate indexing)


.. _https-proxy:

HTTP/S Proxy Mode
-----------------

In addition to "url rewritinng prefix mode" (the default), pywb can also act as a full-fledged HTTP and HTTPS proxy, allowing
any browser or client supporting HTTP and HTTPS proxy to access web archives through the proxy.

Proxy mode can provide access to a single collection at time, eg. instead of accessing ``http://localhost:8080/my-coll/2017/http://example.com/``,
the user enters ``http://example.com/`` and is served content from the ``my-coll`` collection.
As a result, the collection and timestamp must be specified separately.

Configuring HTTP Proxy
^^^^^^^^^^^^^^^^^^^^^^

At this time, pywb requires the collection to be configured at setup time (though collection switching will be added soon).

The collection can be specified by running: ``wayback --proxy my-coll`` or by adding to the config::

  proxy:
    coll: my-coll
    
For HTTP proxy access, this is all that is needed to use the proxy. If pywb is running on port 8080 on localhost, the following curl command should provide proxy access: ``curl -x "localhost:8080"  http://example.com/``


Proxy Recording
^^^^^^^^^^^^^^^

The proxy can additional be set to recording mode, equivalent to access the ``/<my-coll>/record/`` path,
by adding ``recording: true``, as follows::

  proxy:
    coll: my-coll
    recording: true

By default, proxy recording will use the ``live`` collection if not otherwise configured.

See :ref:`recording-mode` for full set of configurable recording options.


HTTPS Proxy and pywb Certificate Authority
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

For HTTPS proxy access, pywb provides its own Certificate Authority and dynamically generates certificates for each host and signes the responses
with these certificates. By design, this allows pywb to act as "man-in-the-middle" servring archived copies of a given site.

However, the pywb certificate authority (CA) will need to be accepted by the browser. The CA cert can be downloaded from pywb directly
using the specical download paths. Recommended set up for using the proxy is as follows:

1. Configure the browser proxy settings host port, for example ``localhost`` and ``8080`` (if running locally)

2. Download the CA:

   * For most browsers, use the PEM format: ``http://wsgiprox/download/pem``

   * For windows, use the PKCS12 format: ``http://wsgiprox/download/p12``

3. You may need to agree to "Trust this CA" to identify websites.

The pywb CA file is automatically generated if it does not exist, and may be added to the key store directly.

Additional proxy options ``ca_name`` and ``ca_file_cache`` allow configuring the location and name of the CA file.

The following are all the available proxy options (only ``coll`` is required)::

  proxy:
    coll: my-coll
    ca_name: pywb HTTPS Proxy CA
    ca_file_cache: ./proxy-certs/pywb-ca.pem
    recording: false

The HTTP/S functionality is provided by the separate :mod:`wsgiprox` utility which provides HTTP/S proxy
for any WSGI application.

See the `wsgiprox README <https://github.com/webrecorder/wsgiprox/blob/master/README.rst>`_ for additional details on how it works.

For more information on custom certificate authority (CA) installation, the `mitmproxy certificate page <http://docs.mitmproxy.org/en/stable/certinstall.html>`_ provides a good overview for installing a custom CA on different platforms.


Compatibility: Redirects, Memento, Flash video overrides
--------------------------------------------------------

Exact Timestamp Redirects
^^^^^^^^^^^^^^^^^^^^^^^^^

By default, pywb does not redirect urls to the 'canonical' respresntation of a url with the exact timestamp.

For example, when requesting ``/my-coll/2017js_/http://example.com/example.js`` but the actual timestamp of the resource is ``2017010203000400``,

there is not a redirect to ``/my-coll/2017010203000400js_/http://example.com/example.js``. Instead, this 'canonical' url is returned in

the ``Content-Location`` value. This behavior is recommended for performance reasons as it avoids an extra roundtrip to the server for a redirect.

However, if the classic redirect behavior is desired, it can be enable by adding::

  redirect_to_exact: true

to the config. This will force any url to be redirected to the exact url, and is consistent with previous behavior and other wayback machine implementations,
at expense of additional network traffic.


Memento Protocol
^^^^^^^^^^^^^^^^

:ref:`memento-api` support is enabled by default, and works with no-timestamp-redirect and classic redirect behaviors.

However, Memento API support can be disabled by adding::

  enable_memento: false


Flash Video Override
^^^^^^^^^^^^^^^^^^^^

A custom system to override Flash video with a custom download via ``youtube-dl`` and replay with a custom player was enabled in previous versions of pywb.
However, this system was not widely used and is in need of maintainance. The system is of less need now that most video is HTML5 based.
For these reasons, this system, previosuly enabled by including the script ``/static/vidrw.js``, is disabled by default.

To enable previous behavior, add to config::

  enable_flash_video_rewrite: true

The system may be revamped in the future and enabled by default, but for now, it is provided for compatibility reasons.