Next week we will be making a major new release of SkyView. This is primarily a structural release where we have centralized the organization of SkyView‘s files. Previously the operational SkyView services used code scattered through a number of directories: CGI, jar, scripts, documents…. Now all of these are collected under a single directory and relative references are used. A number of scripts and documents that were used in the operational system were brought fully within our code management system. So it will be easy to have multiple, independent versions of SkyView available simultaneously. SkyView releases will be delivered into directories named after the version used, e.g., this new release is designated
v3.0.0. [Version 1 of SkyView was our original IDL-based system, Version 2 refers to the existing organization of the Java-based code. Typically the middle number in the version increments when new functionality is released, while the third number is updated when we add surveys or make minor bug fixes or updates.] The
current directory will be linked to whatever is the current operational release. Typically users will only ever reference this
current directory but when a new release is made users will still be able to run the old release by explicitly specifying the version in the SkyView URL they invoke (or they can get a specific version of SkyView-in-a-Jar by downloading the jar from the appropriate directory).
While there will be new URL addresses for most pages, all the old addresses for data requests will be linked to the new locations so existing scripts should not be affected.
There are a few changes: The code for reading survey data has been changed so that if the survey data is 4-byte floating point, it need not be converted to 8-byte floating point. This allows use of much larger input files without exceeding memory constraints. It should also speed things up a bit. We’ve also added in some support for hierarchical imaging where we store an image a multiple resolutions. Both of these changes are in preparation for supporting a set of surveys in the GOOOS regions where some of the source data is very high resolution HST data.
We’ve also added one new small survey, the VLA Stripe 82 survey, a VLA survey of a region where the SDSS coverage is especially deep.
You can try out the new version right away. Next week we’ll begin redirecting the standard URLs here. Some of the old code that we have distributed to access SkyView programmatically does not handle redirect requests so the
pskcall URL it invokes uses a server side redirect that is transparent to the client. Other URLs will redirected using HTTP 301 permanent redirects that any modern clients should handle.
Please let us know if you have any concerns or if you run into any problems.