Thredds Data Server

The THREDDS Data Server (TDS) runs within a Tomcat server, providing these data services:

• An integrated OPeNDAP data server that can serve any data that the NetCDF-Java 2.2 library is able to read.
• An HTTP file server for bulk file transfer.
• A prototype OGC Web Coverage Server (WCS) for gridded data.
• Data services for Unidata's Internet Data Distribution (IDD) data, including:
  • showing the inventory for Forecast Model Run Collections
  • creating subsets of gridded data in netCDF CF-1 format

A THREDDS data server always has a THREDDS Catalog that describes what datasets are available, called the THREDDS data server catalog. These are typically divided into nested catalogs, with the top-level catalog at the root of the tree.

In addition, these catalog services can be used on any catalog.

• show THREDDS catalogs as HTML.
• validate existing catalogs.
• convert a version 0.6 catalog to version 1.0
• subset a catalog with a given dataset as the top dataset.

And these miscellaneous services can also be used:

• Common Data Model Coordinate System Validation

System Requirements

The THREDDS Data Server is written in 100% Java. It requires Java 1.4.2 or above and Tomcat 5.0 or above. We recommend Java 5 and Tomcat 5.5. See Getting Started for details.

Document Links

Read the following, more or less in order, as a Tutorial for configuring and running the TDS:

1. Getting Started
2. Automatic Catalog Generation using datasetScan
3. Aggregation: Using NcML in the TDS
4. Enhanced Catalogs
5. Remote Management
6. Security
7. Performance
8. TDS Configuration Reference
9. Tomcat FAQ
10. Using the THREDDS Data Server with the IDD
11. Web Coverage Server
12. NetCDF Server (Draft Spec)

You can find the build version of this server here.

The current TDS catalog schema

Catalog Services

Each of these services allow you to specify the target catalog with a query parameter:

 catalog=http://server/etc/mycatalog.xml 

If this parameter is left off, the THREDDS top-level server catalog will be used.

The available catalog services:

1. Show any catalog in HTML:

   http://hostname:8080/thredds/catalogServices?catalog=http://server/etc/mycatalog.xml
   

   A form to do the same: http://servername:port/thredds/showHtmlForm.html

2. Validate any catalog:

   http://servername:port/thredds/catalogServices?cmd=validate&catalog=http://server/etc/mycatalog.xml

   A form to do the same: http://servername:port/thredds/validateForm.html

3. Convert a catalog from version 0.6 to version 1.0

   http://servername:port/thredds/catalogServices?cmd=convert&catalog=http://server/etc/mycatalog.xml
   

   A form to do the same: http://servername:port/thredds/convertForm.html

4. Subset a catalog:

   http://hostname:8080/thredds/catalogServices?cmd=subset&catalog=mycatalog.xml&dataset=id

   Here, you must specify a dataset with the given id. A catalog will be constructed containing just that dataset and any of its nested datasets. Inherited services and properties will be included as needed.

   To subset and display in HTML in one step:

   http://hostname:8080/thredds/catalog.html?cmd=subset&catalog=mycatalog.xml&dataset=id

Alternative way to show a catalog in HTML

  http://hostname:8080/thredds/catalogServices?catalog=http://hostname:8080/thredds/dir1/dir2/mycatalog.xml

is the same as

  http://hostname:8080/thredds/dir1/dir2/mycatalog.html

A URL ending in "/"

  http://hostname:8080/thredds/dir1/dir2/

will be converted to:

  http://hostname:8080/thredds /dir1/dir2/catalog.html

however, the catalog is not guaranteed to exist.

Other Web Services:

1. Common Data Model Coordinate System Validation

Use this form: http://servername:port/thredds/cdmValidate.html

To use as a web service:

1. For remote access: http://hostname:8080/thredds/cdmValidate?URL=urlString[&xml=true]
2. For upload a file, POST a multipart/form-data to http://hostname:8080/thredds/cdmValidate

2. Forecast Model Run Inventory

   URLS are of the form : http://servername:port/thredds/modelInventory/{collection path}/

   Example
3. NetCDF Server for subsetting Grids

   Preliminary specification

URLS are of the form :

http://servername:port/thredds/ncServer/{dataset path}?grid={grid1}&grid={grid2}&grid=... [&north=17.3&south=12.088&west=140.2&east=160.0][&start_time=0.0&end_time=12.0][&addLatLon]

To use from a form: http://servername:port/thredds/ncServer/{dataset path}/?showForm

Comments to THREDDS mailgroup or THREDDS support

Go to: THREDDS Tech Page or THREDDS Home Page