Marvin does not work well with the system Python in OSX.
Please, make sure you are using a supported Python installation before
following these instructions. Good installations include
homebrew. After installing one of these distribution,
make sure you are actually using it by running
which python and
which pip. These
commands should print a path to the Python and pip executables within your virtual environment.
To install Marvin, use:
pip install sdss-marvin
If you are using an Anaconda distribution of Python, you may use the following available
here. Once downloaded, set up the virtual environment with:
conda env create -f marvin_2.6.0.yml
To create a clean, isolated, conda virtual environment from scratch, and install marvin into it, do the following:
conda create -n marvin python=3.8 ipython conda activate marvin pip install sdss-marvin
To develop for marvin, follow these instructions:
git clone https://github.com/sdss/marvin cd marvin pip install -e .
Use this installation for development and testing, i.e. if you wish to fix bugs or add new features. This will checkout the repository, install marvin into your python path using pip’s editable mode. Afterwards, you can start developing for Marvin, without having to re-install it every time your code changes.
Access and Authentication¶
By default Marvin is set up to run in
public access mode, with the latest SDSS public data
release, e.g. DR15. You can check your access from within an
In your terminal, run:
Within your ipython session, type:
from marvin import config config.access
config.access of public means you are set up for public access only. In this mode,
you only have access to publically available data. A
config.access of collab indicates you
are set up for SDSS collaboration proprietary data access.
SDSS Collaboration Access¶
For SDSS collaboration members, authentication is required to access proprietary collaboration
data, and Marvin must have
config.access set to collab. See more here.
To set up authentication for Marvin, you must perform the following:
Set up your netrc¶
.netrc authentication to access data content on many domains. To set this up, create
and edit a file in your home called
.netrc and copy these lines inside:
machine api.sdss.org login <username> password <password> machine data.sdss.org login <username> password <password>
<password> with your login credentials. The default SDSS
username and password is also acceptable for anonymous access.
chmod 600 ~/.netrc to make the file only accessible to the user.
API Token Authentication¶
Marvin requires token authentication to grant access and use of its API. Marvin uses the
standard JSON Web Tokens for token authentication. To
receive a valid token, you must login with your valid SDSS
credentials, via the
.netrc. With your
netrc access in place, you will receive a valid
API token. Tokens remain valid for 300 days.:
# login to receive a token config.login() # see token config.token
You will need a token every time you start a new python session. To change this, follow the steps in Automatically Logging In.
Automatically Logging In¶
As the default mode of marvin is public, you will need to authenticate and change to
collab access inside every new
iPython session. To simplify this process, marvin can
be configured to automatically perform the access and authentication checks. To configure marvin,
you must set up a custom marvin configuration file. Inside a
~/.marvin/marvin.yml file, set the following lines:
check_access: True use_token: [token]
You can replace [token] with your authenticated API JSON token (without any string quotes). Upon import of marvin, Marvin will check for valid credentials and automatically set up your collaboration access.
Marvin requires a certain environment structure to access and (optionally) download data. By default,
marvin will look for data files in a directory structure that mirrors the
Science Archive Server. Data downloaded via marvin will
also be stored according to that structure. The root of this directory structure is
defined by the environment variable
$SAS_BASE_DIR. For example, if
to use the
drpall file for DR15, it will try to find it in
The Marvin environment structure is as follows:
====================== ============================================== ====== Environment Variable Default Path Access ====================== ============================================== ====== SAS_BASE_DIR $HOME/sas MANGA_SPECTRO_REDUX $SAS_BASE_DIR/dr15/manga/spectro/redux DR15 MANGA_SPECTRO_ANALYSIS $SAS_BASE_DIR/dr15/manga/spectro/analysis DR15 MANGA_SPECTRO_REDUX $SAS_BASE_DIR/mangawork/manga/spectro/redux collab MANGA_SPECTRO_ANALYSIS $SAS_BASE_DIR/mangawork/manga/spectro/analysis collab ====================== ============================================== ======
Marvin will check for these environment variables in your local system. If the above environment variables are
not already defined, Marvin will use the specifed default paths. Otherwise Marvin will adopt your custom paths.
If you wish to define custom paths, you can update the environment variable paths in your
.cshrc file. As a general advice, if you are
not using other products that require setting those environment variables, you should only
$SAS_BASE_DIR (or not define it and let Marvin configure itself).
Dependencies on SDSS software¶
Marvin depends on three pieces of SDSS-wide software:
marvin_brain: contains some core functionality, such as the API call framework, the basic web server, etc.
tree: defines the structure of the Science Archive Sever, relative paths to data products, etc.
sdss_access: tools for efficiently accessing data files, rsyncing data, etc.
For convenience, Marvin includes these products as external libraries, and you should not need
to worry about them. However, if any of these libraries, except the tree product,
are already installed in your system (i.e., you have defined
$SDSS_ACCESS_DIR), Marvin will use the system wide products instead of its own versions. This is
useful for development but note that it can lead to confusion about what version Marvin is using.
Install and Runtime Issues¶
We can use your help to expand this section. If you have encountered an issue or have questions that should be addressed here, please submit an issue.
Uwsgi package installation failure¶
For Python versions 3.8 and above, the
uwsgi package fails to compile during standard
installation. Alternatively, before installing Marvin, you can install the
uwsgi package using
conda install -c conda-forge uwsgi
Afterwards installaton, marvin should install successfully.
Pip Failure with Python-Memcache¶
If pip fails while installing
python-memcached, make sure that you have the latest version of
setuptools by running
pip install -U setuptools. Then, try running
pip install sdss-marvin again.
How do I update marvin?¶
To upgrade an existing Marvin installation, run:
pip install -U sdss-marvin
pip will update any underlying package on which marvin depends. If you want to
prevent that you can upgrade marvin with
pip install -U --no-deps sdss-marvin. This could,
however, make marvin not work correctly. Instead, you can try
pip install -U --upgrade-strategy only-if-needed sdss-marvin,
which will upgrade a dependency only if needed.
If your Marvin installation fails at any point during the pip install process with permissions problems,
sudo pip install sdss-marvin. Note that an Anaconda or Homebrew distribution will not require
permissions when pip installing things, so if you are receiving permissions errors, you may want to check that
you are not using the Mac OSX system version of Python.
If you receive a permissions error regarding
pip attempting to install a package in a different directory other
than the Anaconda one, e.g.
/lib/python3.6, try following the solution indicated in Marvin Issue 373
How to test that marvin has been installed correctly¶
Marvin is designed to get you started with minimal configuration on your part. However, this means that Marvin may import correctly but may not have all features immediately available. Here are a few commands you can try that will inform you if there are problems with your installation.
From a terminal window, type:
This will perform a variety of checks with Marvin and output the results to the terminal. We may ask you for this output when diagnosing any installation issues. After installing marvin, start a python/ipython session and run:
import marvin print(marvin.config.urlmap)
If you get a dictionary filled with url routes, marvin is connecting correctly to the API server at
Utah and you can use the remote features. If you get
None, you may want to
check the steps in Set up your netrc. If you get an error message such as
BrainError: Requests Timeout Error: HTTPSConnectionPool(host='api.sdss.org', port=443): Read timed out. Your request took longer than 5 minutes and timed out. Please try again or simplify your request.
this means the servers at Utah have timed out and may possibly be down. Simply wait and try again later.
Marvin Remote Access Problems¶
If the above
urlmap test crashes, or you attempt to use a Marvin Tool remotely, and you see this error:
AttributeError: 'Extensions' object has no attribute 'get_extension_for_class'
This is an issue with the Urllib and Requests python package. See this Issue for an ongoing discussion if this problem has been solved.
Lots of Warnings Upon import¶
If you see lots of warnings upon import of marvin, from
/_bootstrap.py and referencing
numpy.ufunc size changed,
may indicate binary incompatibility, such as
import marvin /anaconda3/envs/marvin_public/lib/python3.6/importlib/_bootstrap.py:219: RuntimeWarning: numpy.ufunc size changed, may indicate binary incompatibility. Expected 192 from C header, got 216 from PyObject return f(*args, **kwds) /anaconda3/envs/marvin_public/lib/python3.6/importlib/_bootstrap.py:219: RuntimeWarning: numpy.ufunc size changed, may indicate binary incompatibility. Expected 192 from C header, got 216 from PyObject return f(*args, **kwds)
this arises when a Python package that uses Cython is compiled against a different version of numpy than is actually installed. See this article for more information. The consensus is that these warnings are fairly harmless and benign.
Matplotlib backend problems¶
Some users have reported that after installing marvin they get an error such as:
Python is not installed as a framework. The Mac OS X backend will not be able to function correctly if Python is not installed as a framework.
This problem is caused by matplotlib not being able to use the MacOS backend if you are using
Anaconda. You need to switch your matplolib backend to
TkAgg. Follow these instructions to fix
the problem. If you do want to use the MacOS backend, consider installing Python using
Web Browser Oddities¶
If the MPL dropdown list in the top menu bar is blank, or other elements appear to disappear, this is an indication your browser cache is creating conflicts. The solution is to clear your browser cache, close and restart your browser from scratch. You can also clear your browser cookies.
As a reminder, we recommend these browsers for the best Marvin web experience:
Google Chrome 53+ or higher
Mozilla Firefox 50+ or higher
Safari 10+ or Safari Technology Preview
If you plan to work with Marvin interactively, from the Python terminal, we recommend you use
IPython, which provides many nice features such as autocompletion,
between history, color coding, etc. It’s also especially useful if you plan to use Matplotlib,
as IPython comes with default interactive plotting. If you installed Python via the Anaconda or Miniconda
distributions, then you already have IPython installed. Just run
ipython in your terminal. If you
need to install it, do
pip install jupyter.
Marvin on Windows¶
Marvin was originally designed to work on Mac or Linux operating systems. However it is possible at the moment to get Marvin working on Windows machines. The following guidelines have been tested on a Windows 10 machine running Python 3.6.
Install a Python version for Windows. Make sure to check the box to include Python in your environment variable Paths. If you are using Anaconda to install Python, make sure to check both the “Add Anaconda to my PATH environment variable” and “Register Anaconda as my default Python 3.6”
Marvin expects a HOME directory. Add this snippet of code before any of use of Marvin.
import os os.environ['HOME'] = '/path/you/want/as/marvin/home/directory' os.environ['SAS_BASE_DIR'] = os.path.join(os.getenv("HOME"), 'sas')
- To add a permanent
HOMEpath, follow these instructions.
open File Explorer, right click “This PC” on the left scroll bar and click Properties
on the left, click ‘Advanced System Settings’. You need Admin Privileges to do this.
on the bottom, there should be an ‘Environment Variables’ box. Below the User Variables column, click New.
add a new HOME environment variable that points to /path/you/want/as/marvin/home/directory.
.netrcfile and place it the directory you designated as
HOME. You will need to modify the permissons of this file to match the expected
chmod 600permissions for Mac/Linux users. When creating the file, you can name it as anything but can rename it to
.netrcfrom the command prompt.
With this, you should be able to run Marvin in windows. You can test it with
import marvin. Currently, Marvin cannot download files due to issues with forward slashes in
sdss-access but this will be fixed soon. We will continue to update these guidelines as we make further progress on a Windows-Marvin installation.