Shim is a super-basic SciDB client that exposes limited SciDB functionality through a simple HTTP API. It's based on the mongoose web server.

The program must run on the system that a SciDB coordinator runs on. It does not need to run as the same user that SciDB runs under, but the users do need to be in the same group.

Note: libscidbclient.so must be in shim's library path. This may entail setting LD_LIBRARY_PATH=/opt/scidb//lib before running shim. You don't have to worry about that if you install and run shim as a service.

Note: Shim queries are limited to at most 1,000,000 characters.

See the wwwroot/api.html document for the API documentation, or compile and start shim running and point a browser to http://localhost:8080/api.html. You can also preview the api.html page directly from github at:

Paradigm4/shim/master/wwwroot/api.html

The wwwroot directory also includes an example simple javascript client.

##Installation from binary packages This is the fastest/easiest way to install this service. The author (Bryan Lewis) provides a few pre-built binary packages for SciDB 13.3 on Ubuntu 12.04 here: http://illposed.net/shim_13.3_amd64.deb

# Install with:
sudo gdebi shim_13.3_amd64.deb

# Uninstall with:
apt-get remove shim

and for SciDB 13.3 on RHEL/Centos 6.3 here: http://illposed.net/shim-13.3-1.x86_64.rpm

# Install with:
rpm -i shim-13.3-1.x86_64.rpm
# shim depends on libgomp. If installation fails, install libgomp and try again:
yum install libgomp

# Uninstall with:
yum remove shim

I will continue to make binary packages available when new versions of SciDB are released.

##Compile and Install from Source Note that because shim is a SciDB client it needs the boost, log4cpp and log4cxx development libraries installed to compile. We illustrate installation of Ubuntu build dependencies below:

sudo apt-get install liblog4cpp5-dev liblog4cxx10-dev libboost-dev rubygems
gem install fpm

Once the build dependencies are install, build shim with:

make
sudo make install

# Or, if SCIDB is not in the PATH, can set a Make variable SCIDB that points
# to the SCIDB home directory, for example for version 13.3:

make SCIDB=/opt/scidb/13.3
sudo make SCIDB=/opt/scidb/13.3 install

Optionally install as a service

You can install shim as a system service so that it just runs all the time with:

sudo make SCIDB=/opt/scidb/13.3 service

If you install shim as a service and want to change its default options, for example the default HTTP port or port to talk to SciDB on, you'll need to edit the /etc/init.d/shimsvc file. See the discussion of command line parameters below.

Optionally build deb or rpm packages

You can build the service version of shim into packages for Ubuntu 12.04 or RHEL/CentOS 6 with

make deb-pkg
make rpm-pkg

respectively. Building packages requires that certain extra packaging programs are available, including rpmbuild for RHEL/CentOS and the Ruby-based fpm packaging utility on all systems.

Usage

shim [-h] [-f] [-p <http port>] [-r <document root>] [-s <scidb port>]

where, -f means run in the foreground (defaults to background), -h means help.

If you installed the service version, then you can control when shim is running with the usual mechanism, for example:

/etc/init.d/shimsvc stop
/etc/init.d/shimsvc start

Uninstall

We explicitly define our SCIDB home directory for Make in the example below:

sudo make SCIDB=/opt/scidb/13.3 uninstall

Log files

Shim prints messages to the system log. The syslog file location varies, but can usually be found in /var/log/syslog or /var/log/messages.