Fix extraction from youtube.

[youtubedl] / README.txt

diff --git a/README.txt b/README.txt
index 24959f03234926da60136026cc16348bfbdb812a..6ba6d68caf747152f10a67810815e53ab85b3b2e 100644 (file)
--- a/README.txt
+++ b/README.txt
@@ -20,7 +20,7 @@ youtube-dl - download videos from youtube.com or other video platforms
 INSTALLATION
 
 
 INSTALLATION
 
 

-To install it right away for all UNIX users (Linux, OS X, etc.), type:
+To install it right away for all UNIX users (Linux, macOS, etc.), type:

 
     sudo curl -L https://yt-dl.org/downloads/latest/youtube-dl -o /usr/local/bin/youtube-dl
     sudo chmod a+rx /usr/local/bin/youtube-dl
 
     sudo curl -L https://yt-dl.org/downloads/latest/youtube-dl -o /usr/local/bin/youtube-dl
     sudo chmod a+rx /usr/local/bin/youtube-dl


@@ -41,7 +41,7 @@ You can also use pip:
 This command will update youtube-dl if you have already installed it.
 See the pypi page for more information.
 
 This command will update youtube-dl if you have already installed it.
 See the pypi page for more information.
 

-OS X users can install youtube-dl with Homebrew:
+macOS users can install youtube-dl with Homebrew:

 
     brew install youtube-dl
 
 
     brew install youtube-dl
 


@@ -116,8 +116,8 @@ OPTIONS
 Network Options:
 
     --proxy URL                      Use the specified HTTP/HTTPS/SOCKS proxy.
 Network Options:
 
     --proxy URL                      Use the specified HTTP/HTTPS/SOCKS proxy.

-                                     To enable experimental SOCKS proxy, specify
-                                     a proper scheme. For example
+                                     To enable SOCKS proxy, specify a proper
+                                     scheme. For example

                                      socks5://127.0.0.1:1080/. Pass in an empty
                                      string (--proxy "") for direct connection
     --socket-timeout SECONDS         Time to wait before giving up, in seconds
                                      socks5://127.0.0.1:1080/. Pass in an empty
                                      string (--proxy "") for direct connection
     --socket-timeout SECONDS         Time to wait before giving up, in seconds


@@ -131,16 +131,18 @@ Geo Restriction:
     --geo-verification-proxy URL     Use this proxy to verify the IP address for
                                      some geo-restricted sites. The default
                                      proxy specified by --proxy (or none, if the
     --geo-verification-proxy URL     Use this proxy to verify the IP address for
                                      some geo-restricted sites. The default
                                      proxy specified by --proxy (or none, if the

-                                     options is not present) is used for the
+                                     option is not present) is used for the

                                      actual downloading.
     --geo-bypass                     Bypass geographic restriction via faking
                                      actual downloading.
     --geo-bypass                     Bypass geographic restriction via faking

-                                     X-Forwarded-For HTTP header (experimental)
+                                     X-Forwarded-For HTTP header

     --no-geo-bypass                  Do not bypass geographic restriction via
                                      faking X-Forwarded-For HTTP header
     --no-geo-bypass                  Do not bypass geographic restriction via
                                      faking X-Forwarded-For HTTP header

-                                     (experimental)

     --geo-bypass-country CODE        Force bypass geographic restriction with
                                      explicitly provided two-letter ISO 3166-2
     --geo-bypass-country CODE        Force bypass geographic restriction with
                                      explicitly provided two-letter ISO 3166-2

-                                     country code (experimental)
+                                     country code
+    --geo-bypass-ip-block IP_BLOCK   Force bypass geographic restriction with
+                                     explicitly provided IP block in CIDR
+                                     notation

 
 
 Video Selection:
 
 
 Video Selection:


@@ -235,7 +237,7 @@ Download Options:
     --playlist-reverse               Download playlist videos in reverse order
     --playlist-random                Download playlist videos in random order
     --xattr-set-filesize             Set file xattribute ytdl.filesize with
     --playlist-reverse               Download playlist videos in reverse order
     --playlist-random                Download playlist videos in random order
     --xattr-set-filesize             Set file xattribute ytdl.filesize with

-                                     expected file size (experimental)
+                                     expected file size

     --hls-prefer-native              Use the native HLS downloader instead of
                                      ffmpeg
     --hls-prefer-ffmpeg              Use ffmpeg instead of the native HLS
     --hls-prefer-native              Use the native HLS downloader instead of
                                      ffmpeg
     --hls-prefer-ffmpeg              Use ffmpeg instead of the native HLS


@@ -254,7 +256,9 @@ Download Options:
 Filesystem Options:
 
     -a, --batch-file FILE            File containing URLs to download ('-' for
 Filesystem Options:
 
     -a, --batch-file FILE            File containing URLs to download ('-' for

-                                     stdin)
+                                     stdin), one URL per line. Lines starting
+                                     with '#', ';' or ']' are considered as
+                                     comments and ignored.

     --id                             Use only video ID in file name
     -o, --output TEMPLATE            Output filename template, see the "OUTPUT
                                      TEMPLATE" for all the info
     --id                             Use only video ID in file name
     -o, --output TEMPLATE            Output filename template, see the "OUTPUT
                                      TEMPLATE" for all the info


@@ -470,9 +474,9 @@ Post-processing Options:
                                      default; fix file if we can, warn
                                      otherwise)
     --prefer-avconv                  Prefer avconv over ffmpeg for running the
                                      default; fix file if we can, warn
                                      otherwise)
     --prefer-avconv                  Prefer avconv over ffmpeg for running the

-                                     postprocessors (default)
-    --prefer-ffmpeg                  Prefer ffmpeg over avconv for running the

                                      postprocessors
                                      postprocessors

+    --prefer-ffmpeg                  Prefer ffmpeg over avconv for running the
+                                     postprocessors (default)

     --ffmpeg-location PATH           Location of the ffmpeg/avconv binary;
                                      either the path to the binary or its
                                      containing directory.
     --ffmpeg-location PATH           Location of the ffmpeg/avconv binary;
                                      either the path to the binary or its
                                      containing directory.


@@ -489,7 +493,7 @@ CONFIGURATION
 
 
 You can configure youtube-dl by placing any supported command line
 
 
 You can configure youtube-dl by placing any supported command line

-option to a configuration file. On Linux and OS X, the system wide
+option to a configuration file. On Linux and macOS, the system wide

 configuration file is located at /etc/youtube-dl.conf and the user wide
 configuration file at ~/.config/youtube-dl/config. On Windows, the user
 wide configuration file locations are %APPDATA%\youtube-dl\config.txt or
 configuration file is located at /etc/youtube-dl.conf and the user wide
 configuration file at ~/.config/youtube-dl/config. On Windows, the user
 wide configuration file locations are %APPDATA%\youtube-dl\config.txt or


@@ -572,8 +576,8 @@ However, it may contain special sequences that will be replaced when
 downloading each video. The special sequences may be formatted according
 to python string formatting operations. For example, %(NAME)s or
 %(NAME)05d. To clarify, that is a percent symbol followed by a name in
 downloading each video. The special sequences may be formatted according
 to python string formatting operations. For example, %(NAME)s or
 %(NAME)05d. To clarify, that is a percent symbol followed by a name in

-parentheses, followed by a formatting operations. Allowed names along
-with sequence type are:
+parentheses, followed by formatting operations. Allowed names along with
+sequence type are:

 
 -   id (string): Video identifier
 -   title (string): Video title
 
 -   id (string): Video identifier
 -   title (string): Video title


@@ -590,6 +594,8 @@ with sequence type are:
     available
 -   upload_date (string): Video upload date (YYYYMMDD)
 -   uploader_id (string): Nickname or id of the video uploader
     available
 -   upload_date (string): Video upload date (YYYYMMDD)
 -   uploader_id (string): Nickname or id of the video uploader

+-   channel (string): Full name of the channel the video is uploaded on
+-   channel_id (string): Id of the channel

 -   location (string): Physical location where the video was filmed
 -   duration (numeric): Length of the video in seconds
 -   view_count (numeric): How many users have watched the video on the
 -   location (string): Physical location where the video was filmed
 -   duration (numeric): Length of the video in seconds
 -   view_count (numeric): How many users have watched the video on the


@@ -1143,7 +1149,7 @@ Use the --cookies option, for example
 
 In order to extract cookies from browser use any conforming browser
 extension for exporting cookies. For example, cookies.txt (for Chrome)
 
 In order to extract cookies from browser use any conforming browser
 extension for exporting cookies. For example, cookies.txt (for Chrome)

-or Export Cookies (for Firefox).
+or cookies.txt (for Firefox).

 
 Note that the cookies file must be in Mozilla/Netscape format and the
 first line of the cookies file must be either # HTTP Cookie File or
 
 Note that the cookies file must be in Mozilla/Netscape format and the
 first line of the cookies file must be either # HTTP Cookie File or


@@ -1351,12 +1357,12 @@ yourextractor):
 1.  Fork this repository
 2.  Check out the source code with:
 
 1.  Fork this repository
 2.  Check out the source code with:
 

-        git clone git@github.com:YOUR_GITHUB_USERNAME/youtube-dl.git
+         git clone git@github.com:YOUR_GITHUB_USERNAME/youtube-dl.git

 
 3.  Start a new git branch with
 
 
 3.  Start a new git branch with
 

-        cd youtube-dl
-        git checkout -b yourextractor
+         cd youtube-dl
+         git checkout -b yourextractor

 
 4.  Start with this simple template and save it to
     youtube_dl/extractor/yourextractor.py:
 
 4.  Start with this simple template and save it to
     youtube_dl/extractor/yourextractor.py:


@@ -1413,10 +1419,13 @@ yourextractor):
     methods and a detailed description of what your extractor should and
     may return. Add tests and code for as many as you want.
 8.  Make sure your code follows youtube-dl coding conventions and check
     methods and a detailed description of what your extractor should and
     may return. Add tests and code for as many as you want.
 8.  Make sure your code follows youtube-dl coding conventions and check

-    the code with flake8. Also make sure your code works under all
-    Python versions claimed supported by youtube-dl, namely 2.6, 2.7,
-    and 3.2+.
-9.  When the tests pass, add the new files and commit them and push the
+    the code with flake8:
+
+         $ flake8 youtube_dl/extractor/yourextractor.py
+
+9.  Make sure your code works under all Python versions claimed
+    supported by youtube-dl, namely 2.6, 2.7, and 3.2+.
+10. When the tests pass, add the new files and commit them and push the

     result, like this:
 
         $ git add youtube_dl/extractor/extractors.py
     result, like this:
 
         $ git add youtube_dl/extractor/extractors.py


@@ -1424,7 +1433,7 @@ yourextractor):
         $ git commit -m '[yourextractor] Add new extractor'
         $ git push origin yourextractor
 
         $ git commit -m '[yourextractor] Add new extractor'
         $ git push origin yourextractor
 

-10. Finally, create a pull request. We'll then review and merge it.
+11. Finally, create a pull request. We'll then review and merge it.

 
 In any case, thank you very much for your contributions!
 
 
 In any case, thank you very much for your contributions!
 


@@ -1553,9 +1562,31 @@ fallback scenario:
 This code will try to extract from meta first and if it fails it will
 try extracting og:title from a webpage.
 
 This code will try to extract from meta first and if it fails it will
 try extracting og:title from a webpage.
 

-Make regular expressions flexible
+Regular expressions
+
+Don't capture groups you don't use
+
+Capturing group must be an indication that it's used somewhere in the
+code. Any group that is not used must be non capturing.
+
+Example
+
+Don't capture id attribute name here since you can't use it for anything
+anyway.
+
+Correct:
+
+    r'(?:id|ID)=(?P<id>\d+)'
+
+Incorrect:
+
+    r'(id|ID)=(?P<id>\d+)'

 
 

-When using regular expressions try to write them fuzzy and flexible.
+Make regular expressions relaxed and flexible
+
+When using regular expressions try to write them fuzzy, relaxed and
+flexible, skipping insignificant parts that are more likely to change,
+allowing both single and double quotes for quoted values and so on.

 
 Example
 
 
 Example
 


@@ -1583,11 +1614,48 @@ The code definitely should not look like:
         r'<span style="position: absolute; left: 910px; width: 90px; float: right; z-index: 9999;" class="title">(.*?)</span>',
         webpage, 'title', group='title')
 
         r'<span style="position: absolute; left: 910px; width: 90px; float: right; z-index: 9999;" class="title">(.*?)</span>',
         webpage, 'title', group='title')
 

+Long lines policy
+
+There is a soft limit to keep lines of code under 80 characters long.
+This means it should be respected if possible and if it does not make
+readability and code maintenance worse.
+
+For example, you should NEVER split long string literals like URLs or
+some other often copied entities over multiple lines to fit this limit:
+
+Correct:
+
+    'https://www.youtube.com/watch?v=FqZTN594JQw&list=PLMYEtVRpaqY00V9W81Cwmzp6N6vZqfUKD4'
+
+Incorrect:
+
+    'https://www.youtube.com/watch?v=FqZTN594JQw&list='
+    'PLMYEtVRpaqY00V9W81Cwmzp6N6vZqfUKD4'
+

 Use safe conversion functions
 
 Use safe conversion functions
 

-Wrap all extracted numeric data into safe functions from utils:
-int_or_none, float_or_none. Use them for string to number conversions as
-well.
+Wrap all extracted numeric data into safe functions from
+youtube_dl/utils.py: int_or_none, float_or_none. Use them for string to
+number conversions as well.
+
+Use url_or_none for safe URL processing.
+
+Use try_get for safe metadata extraction from parsed JSON.
+
+Explore youtube_dl/utils.py for more useful convenience functions.
+
+More examples
+
+Safely extract optional description from parsed JSON
+
+    description = try_get(response, lambda x: x['result']['video'][0]['summary'], compat_str)
+
+Safely extract more optional metadata
+
+    video = try_get(response, lambda x: x['result']['video'][0], dict) or {}
+    description = video.get('summary')
+    duration = float_or_none(video.get('durationMs'), scale=1000)
+    view_count = int_or_none(video.get('views'))