我想使用 ZBar来自 Heroku 上的 Python .在常规的 Ubuntu 14.04 服务器上，我可以运行
sudo apt-get install python-qrtools
-- 或者 --
sudo apt-get install zbar-tools
sudo apt-get install libzbar-dev
sudo apt-get install python-zbar
在第一个或最后三个之后，我可以从 Python 执行 import zbar。所以使用 heroku-buildpack-apt (结合 heroku-buildpack-multi )我尝试了两种选择。在这两种情况下，它似乎都正确安装了所有内容(请参阅下面的安装日志)，但在 python 命令行上尝试它总是会产生:
>>> import zbar
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named zbar
看到 Heroku 日志(下方)将 Linux 发行版列为 Ubuntu Trusty (=14.04)，我不明白为什么它在我自己的 14.04 安装上运行，但在 Heroku 上不起作用。
有谁知道为什么这不起作用以及我如何在 Heroku 上安装所需的软件包？欢迎所有提示!
尝试安装 python-qrtools 时的 Heroku 安装日志:
remote: =====> Downloading Buildpack: https://github.com/ddollar/heroku-buildpack-apt
remote: =====> Detected Framework: Apt
remote: -----> Updating apt caches
remote: Ign http://archive.ubuntu.com trusty InRelease
remote: Ign http://archive.ubuntu.com trusty-security InRelease
remote: Ign http://archive.ubuntu.com trusty-updates InRelease
remote: Hit http://archive.ubuntu.com trusty Release.gpg
remote: Hit http://archive.ubuntu.com trusty-security Release.gpg
remote: Hit http://archive.ubuntu.com trusty-updates Release.gpg
remote: Hit http://archive.ubuntu.com trusty Release
remote: Hit http://archive.ubuntu.com trusty-security Release
remote: Hit http://archive.ubuntu.com trusty-updates Release
remote: Hit http://archive.ubuntu.com trusty/main amd64 Packages
remote: Hit http://archive.ubuntu.com trusty/universe amd64 Packages
remote: Hit http://archive.ubuntu.com trusty/main Translation-en
remote: Hit http://archive.ubuntu.com trusty/universe Translation-en
remote: Hit http://archive.ubuntu.com trusty-security/main amd64 Packages
remote: Hit http://archive.ubuntu.com trusty-security/main Translation-en
remote: Hit http://archive.ubuntu.com trusty-updates/main amd64 Packages
remote: Hit http://archive.ubuntu.com trusty-updates/main Translation-en
remote: Ign http://archive.ubuntu.com trusty/main Translation-en_US
remote: Ign http://archive.ubuntu.com trusty/universe Translation-en_US
remote: Reading package lists...
remote: -----> Fetching .debs for python-qrtools
remote: Reading package lists...
remote: Building dependency tree...
remote: The following extra packages will be installed:
remote: libqrencode3 libv4l-0 libv4lconvert0 libwebp5 libwebpmux1 libzbar0
remote: python-imaging python-pil python-zbar qrencode
remote: Suggested packages:
remote: python-pil-doc python-pil-dbg
remote: The following NEW packages will be installed:
remote: libqrencode3 libv4l-0 libv4lconvert0 libwebp5 libwebpmux1 libzbar0
remote: python-imaging python-pil python-qrtools python-zbar qrencode
remote: 0 upgraded, 11 newly installed, 0 to remove and 81 not upgraded.
remote: Need to get 0 B/721 kB of archives.
remote: After this operation, 2,724 kB of additional disk space will be used.
remote: Download complete and in download only mode
remote: -----> Installing libqrencode3_3.4.2-1_amd64.deb
remote: -----> Installing libv4l-0_1.0.1-1_amd64.deb
remote: -----> Installing libv4lconvert0_1.0.1-1_amd64.deb
remote: -----> Installing libwebp5_0.4.0-4_amd64.deb
remote: -----> Installing libwebpmux1_0.4.0-4_amd64.deb
remote: -----> Installing libzbar0_0.10+doc-9build1_amd64.deb
remote: -----> Installing python-imaging_2.3.0-1ubuntu3_all.deb
remote: -----> Installing python-pil_2.3.0-1ubuntu3_amd64.deb
remote: -----> Installing python-qrtools_1.4~bzr16-1ubuntu1_all.deb
remote: -----> Installing python-zbar_0.10+doc-9build1_amd64.deb
remote: -----> Installing qrencode_3.4.2-1_amd64.deb
remote: -----> Writing profile script
remote: =====> Downloading Buildpack: https://github.com/heroku/heroku-buildpack-python.git
remote: =====> Detected Framework: Python
remote: -----> Installing dependencies with pip
remote: Cleaning up...
remote:
remote: Using release configuration from last framework (Python).
remote: -----> Discovering process types
remote: Procfile declares types -> web
remote:
remote: -----> Compressing... done, 39.4MB
remote: -----> Launching... done, v22
remote: https://mysterious-man-1234.herokuapp.com/ deployed to Heroku
remote:
remote: Verifying deploy... done.
尝试安装 zbar-tools、libzbar-dev 和 python-zbar 时的 Heroku 安装日志:
remote: =====> Downloading Buildpack: https://github.com/ddollar/heroku-buildpack-apt
remote: =====> Detected Framework: Apt
remote: -----> Updating apt caches
remote: Ign http://archive.ubuntu.com trusty InRelease
remote: Ign http://archive.ubuntu.com trusty-security InRelease
remote: Ign http://archive.ubuntu.com trusty-updates InRelease
remote: Hit http://archive.ubuntu.com trusty Release.gpg
remote: Get:1 http://archive.ubuntu.com trusty-security Release.gpg [933 B]
remote: Get:2 http://archive.ubuntu.com trusty-updates Release.gpg [933 B]
remote: Hit http://archive.ubuntu.com trusty Release
remote: Get:3 http://archive.ubuntu.com trusty-security Release [62.0 kB]
remote: Get:4 http://archive.ubuntu.com trusty-updates Release [62.0 kB]
remote: Hit http://archive.ubuntu.com trusty/main amd64 Packages
remote: Hit http://archive.ubuntu.com trusty/universe amd64 Packages
remote: Hit http://archive.ubuntu.com trusty/main Translation-en
remote: Hit http://archive.ubuntu.com trusty/universe Translation-en
remote: Get:5 http://archive.ubuntu.com trusty-security/main amd64 Packages [181 kB]
remote: Hit http://archive.ubuntu.com trusty-security/main Translation-en
remote: Get:6 http://archive.ubuntu.com trusty-updates/main amd64 Packages [384 kB]
remote: Hit http://archive.ubuntu.com trusty-updates/main Translation-en
remote: Ign http://archive.ubuntu.com trusty/main Translation-en_US
remote: Ign http://archive.ubuntu.com trusty/universe Translation-en_US
remote: Fetched 691 kB in 3s (219 kB/s)
remote: Reading package lists...
remote: -----> Fetching .debs for zbar-tools
remote: Reading package lists...
remote: Building dependency tree...
remote: The following extra packages will be installed:
remote: libv4l-0 libv4lconvert0 libzbar0
remote: The following NEW packages will be installed:
remote: libv4l-0 libv4lconvert0 libzbar0 zbar-tools
remote: 0 upgraded, 4 newly installed, 0 to remove and 81 not upgraded.
remote: Need to get 0 B/231 kB of archives.
remote: After this operation, 861 kB of additional disk space will be used.
remote: Download complete and in download only mode
remote: -----> Fetching .debs for libzbar-dev
remote: Reading package lists...
remote: Building dependency tree...
remote: The following extra packages will be installed:
remote: libmagick++-dev libmagick++5 libv4l-0 libv4lconvert0 libzbar0
remote: The following NEW packages will be installed:
remote: libmagick++-dev libmagick++5 libv4l-0 libv4lconvert0 libzbar-dev libzbar0
remote: 0 upgraded, 6 newly installed, 0 to remove and 81 not upgraded.
remote: Need to get 0 B/563 kB of archives.
remote: After this operation, 2,980 kB of additional disk space will be used.
remote: Download complete and in download only mode
remote: -----> Fetching .debs for python-zbar
remote: Reading package lists...
remote: Building dependency tree...
remote: The following extra packages will be installed:
remote: libv4l-0 libv4lconvert0 libzbar0
remote: The following NEW packages will be installed:
remote: libv4l-0 libv4lconvert0 libzbar0 python-zbar
remote: 0 upgraded, 4 newly installed, 0 to remove and 81 not upgraded.
remote: Need to get 0 B/225 kB of archives.
remote: After this operation, 873 kB of additional disk space will be used.
remote: Download complete and in download only mode
remote: -----> Installing libmagick++5_8%3a6.7.7.10-6ubuntu3_amd64.deb
remote: -----> Installing libmagick++-dev_8%3a6.7.7.10-6ubuntu3_amd64.deb
remote: -----> Installing libqrencode3_3.4.2-1_amd64.deb
remote: -----> Installing libv4l-0_1.0.1-1_amd64.deb
remote: -----> Installing libv4lconvert0_1.0.1-1_amd64.deb
remote: -----> Installing libwebp5_0.4.0-4_amd64.deb
remote: -----> Installing libwebpmux1_0.4.0-4_amd64.deb
remote: -----> Installing libzbar0_0.10+doc-9build1_amd64.deb
remote: -----> Installing libzbar-dev_0.10+doc-9build1_amd64.deb
remote: -----> Installing python-imaging_2.3.0-1ubuntu3_all.deb
remote: -----> Installing python-pil_2.3.0-1ubuntu3_amd64.deb
remote: -----> Installing python-qrtools_1.4~bzr16-1ubuntu1_all.deb
remote: -----> Installing python-zbar_0.10+doc-9build1_amd64.deb
remote: -----> Installing qrencode_3.4.2-1_amd64.deb
remote: -----> Installing zbar-tools_0.10+doc-9build1_amd64.deb
remote: -----> Writing profile script
remote: Using release configuration from last framework (Apt).
remote: -----> Discovering process types
remote: Procfile declares types -> web
remote:
remote: -----> Compressing... done, 39.8MB
remote: -----> Launching... done, v24
remote: https://mystery-man-1234.herokuapp.com/ deployed to Heroku
remote:
remote: Verifying deploy... done.
最佳答案
在@PadraicCunningham 的惊人帮助下，我设法找到了解决方案。问题原来是heroku-buildpack-apt在新创建的文件夹 /app/.apt/ 中安装东西，该文件夹不在 PYTHONPATH 中。
所以我将相关文件夹添加到 heroku 上的 PYTHONPATH 中，如下所示:
heroku config:add PYTHONPATH=/app/.apt/usr/lib/python2.7/dist-packages/
这解决了问题。再次非常感谢 PadraicCunningham 帮助我找到了这个问题!
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