thredds.servlet

Class DataRootHandler

java.lang.Object

thredds.servlet.DataRootHandler

All Implemented Interfaces:

org.springframework.beans.factory.InitializingBean

@Component
public final class DataRootHandler
extends Object
implements org.springframework.beans.factory.InitializingBean

The DataRootHandler manages all the "data roots" for a given web application and provides mappings from URLs to catalog and data objects (e.g., InvCatalog and CrawlableDataset).

The "data roots" are read in from one or more trees of config catalogs and are defined by the datasetScan and datasetRoot elements in the config catalogs.

Uses the singleton design pattern.

Author:

caron

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	DataRootHandler.ConfigListener To receive notice of TDS configuration events, implement this interface and use the DataRootHandler.registerConfigListener() method to register an instance with a DataRootHandler instance.
class	DataRootHandler.DataRoot
class	DataRootHandler.DataRootMatch

Method Summary

Methods

Modifier and Type	Method and Description
void	afterPropertiesSet()
DataRootHandler.DataRootMatch	findDataRootMatch(javax.servlet.http.HttpServletRequest req) Extract the DataRoot from the request.
DataRootHandler.DataRootMatch	findDataRootMatch(String spath)
InvCatalog	getCatalog(String path, URI baseURI) If a catalog exists and is allowed (not filtered out) for the given path, return the catalog as an InvCatalog.
CrawlableDataset	getCrawlableDataset(String path) Return the CrawlableDataset to which the given path maps, null if the dataset does not exist or the matching InvDatasetScan filters out the requested CrawlableDataset.
File	getCrawlableDatasetAsFile(String path) Return the java.io.File represented by the CrawlableDataset to which the given path maps.
URI	getCrawlableDatasetAsOpendapUri(String path) Return the OPeNDAP URI represented by the CrawlableDataset to which the given path maps.
InvDatasetFeatureCollection	getFeatureCollection(String want)
List<InvDatasetFeatureCollection>	getFeatureCollections()
static DataRootHandler	getInstance() Get the singleton.
org.jdom.Element	getNcML(String path) Try to match the given path with all available data roots.
PathMatcher	getPathMatcher()
InvCatalog	getProxyDatasetResolverCatalog(String path, URI baseURI)
void	handleRequestForDataset(String path, DataServiceProvider dsp, javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse res) Deprecated. DO NOT USE
void	handleRequestForProxyDatasetResolverCatalog(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse res) Deprecated.
boolean	hasDataRootMatch(String path) Return true if the given path matches a dataRoot, otherwise return false.
void	initCatalogs(List<String> configCatalogRoots)
boolean	isProxyDataset(String path)
boolean	isProxyDatasetResolver(String path)
void	makeDebugActions()
boolean	processReqForCatalog(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse res) Deprecated. Instead forward() request to
boolean	processReqForLatestDataset(javax.servlet.http.HttpServlet servlet, javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse res) Deprecated. Instead use processReqForCatalog() which provides more general proxy dataset handling.
boolean	registerConfigListener(DataRootHandler.ConfigListener cl)
void	reinit() Reinitialize lists of static catalogs, data roots, dataset Ids.
void	setDataRootLocationAliasExpanders(Map<String,String> aliases)
static void	setInstance(DataRootHandler drh) Initialize the DataRootHandler singleton instance.
boolean	unregisterConfigListener(DataRootHandler.ConfigListener cl)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

setInstance

public static void setInstance(DataRootHandler drh)

Initialize the DataRootHandler singleton instance.

This method should only be called once. Additional calls will be ignored.

Parameters:

drh - the singleton instance of DataRootHandler being used

getInstance

public static DataRootHandler getInstance()

Get the singleton.

The setInstance() method must be called before this method is called.

Returns:

the singleton instance.

Throws:

IllegalStateException - if setInstance() has not been called.

setDataRootLocationAliasExpanders

public void setDataRootLocationAliasExpanders(Map<String,String> aliases)

afterPropertiesSet

public void afterPropertiesSet()

Specified by:

afterPropertiesSet in interface org.springframework.beans.factory.InitializingBean

registerConfigListener

public boolean registerConfigListener(DataRootHandler.ConfigListener cl)

unregisterConfigListener

public boolean unregisterConfigListener(DataRootHandler.ConfigListener cl)

reinit

public void reinit()

Reinitialize lists of static catalogs, data roots, dataset Ids.

initCatalogs

public void initCatalogs(List<String> configCatalogRoots)

getFeatureCollections

public List<InvDatasetFeatureCollection> getFeatureCollections()

getFeatureCollection

public InvDatasetFeatureCollection getFeatureCollection(String want)

findDataRootMatch

public DataRootHandler.DataRootMatch findDataRootMatch(javax.servlet.http.HttpServletRequest req)

Extract the DataRoot from the request. Use this when you need to manipulate the path based on the part that matches a DataRoot.

Parameters:

req - the request

Returns:

the DataRootMatch, or null if not found

findDataRootMatch

public DataRootHandler.DataRootMatch findDataRootMatch(String spath)

hasDataRootMatch

public boolean hasDataRootMatch(String path)

Return true if the given path matches a dataRoot, otherwise return false. A succesful match means that the request is either for a dynamic catalog or a dataset.

Parameters:

path - the request path, ie req.getServletPath() + req.getPathInfo()

Returns:

true if the given path matches a dataRoot, otherwise false.

getCrawlableDataset

public CrawlableDataset getCrawlableDataset(String path)
                                     throws IOException

Return the CrawlableDataset to which the given path maps, null if the dataset does not exist or the matching InvDatasetScan filters out the requested CrawlableDataset.

Use this method to check that a data request is requesting an allowed dataset.

Parameters:

path - the request path.

Returns:

the requested CrawlableDataset or null if the requested dataset is not allowed by the matching InvDatasetScan.

Throws:

IOException - if an I/O error occurs while locating the requested dataset.

getCrawlableDatasetAsFile

public File getCrawlableDatasetAsFile(String path)

Return the java.io.File represented by the CrawlableDataset to which the given path maps. Null is returned if the dataset does not exist, the matching InvDatasetScan or DataRoot filters out the requested CrawlableDataset, the CrawlableDataset does not represent a File (i.e., it is not a CrawlableDatasetFile), or an I/O error occurs whil locating the requested dataset.

Parameters:

path - the request path.

Returns:

the requested java.io.File or null.

Throws:

IllegalStateException - if the request is not for a descendant of (or the same as) the matching DatasetRoot collection location.

getCrawlableDatasetAsOpendapUri

public URI getCrawlableDatasetAsOpendapUri(String path)

Return the OPeNDAP URI represented by the CrawlableDataset to which the given path maps. Null is returned if the dataset does not exist, the matching InvDatasetScan or DataRoot filters out the requested CrawlableDataset, the CrawlableDataset is not a CrawlableDatasetDods, or an I/O error occurs while locating the requested dataset.

Parameters:

path - the request path.

Returns:

the requested OPeNDAP URI or null.

Throws:

IllegalStateException - if the request is not for a descendant of (or the same as) the matching DatasetRoot collection location.

isProxyDataset

public boolean isProxyDataset(String path)

isProxyDatasetResolver

public boolean isProxyDatasetResolver(String path)

getProxyDatasetResolverCatalog

public InvCatalog getProxyDatasetResolverCatalog(String path,
                                        URI baseURI)

handleRequestForProxyDatasetResolverCatalog

public void handleRequestForProxyDatasetResolverCatalog(javax.servlet.http.HttpServletRequest req,
                                               javax.servlet.http.HttpServletResponse res)
                                                 throws IOException

Deprecated.

Throws:

IOException

handleRequestForDataset

public void handleRequestForDataset(String path,
                           DataServiceProvider dsp,
                           javax.servlet.http.HttpServletRequest req,
                           javax.servlet.http.HttpServletResponse res)
                             throws IOException

Deprecated. DO NOT USE

DO NOT USE, this is Ethan's attempt at designing a generic way to handle data requests.

Only used is in ExampleThreddsServlet.

Parameters:

path -

dsp -

req -

res -

Throws:

IOException

processReqForCatalog

public boolean processReqForCatalog(javax.servlet.http.HttpServletRequest req,
                           javax.servlet.http.HttpServletResponse res)
                             throws IOException,
                                    javax.servlet.ServletException

Deprecated. Instead forward() request to

This looks to see if this is a request for a catalog. The request must end in ".html" or ".xml" or "/" Check to see if a static or dynamic catalog exists for it. If so, it processes the request completely. req.getPathInfo() is used for the path (ie ignores context and servlet path)

Parameters:

req - the request

res - the response

Returns:

true if request was handled

Throws:

IOException - on I/O error

javax.servlet.ServletException - on other errors

getCatalog

public InvCatalog getCatalog(String path,
                    URI baseURI)

If a catalog exists and is allowed (not filtered out) for the given path, return the catalog as an InvCatalog. Otherwise, return null.

The validity of the returned catalog is not guaranteed. Use InvCatalog.check() to check that the catalog is valid.

Parameters:

path - the path for the requested catalog.

baseURI - the base URI for the catalog, used to resolve relative URLs.

Returns:

the requested InvCatalog, or null if catalog does not exist or is not allowed.

processReqForLatestDataset

public boolean processReqForLatestDataset(javax.servlet.http.HttpServlet servlet,
                                 javax.servlet.http.HttpServletRequest req,
                                 javax.servlet.http.HttpServletResponse res)
                                   throws IOException

Deprecated. Instead use processReqForCatalog() which provides more general proxy dataset handling.

Process a request for the "latest" dataset. This must be configured through the datasetScan element. Typically you call if the path ends with "latest.xml". Actually this is a "resolver" service, that returns a catalog.xml containing latest dataset.

Parameters:

servlet - requesting servlet

req - request

res - response

Returns:

true if request was processed successfully.

Throws:

IOException - if have I/O trouble writing response.

getNcML

public org.jdom.Element getNcML(String path)

Try to match the given path with all available data roots. If match, then see if there is an NcML document associated with the path.

Parameters:

path - the reletive path, ie req.getServletPath() + req.getPathInfo()

Returns:

the NcML (as a JDom element) assocated assocated with this path, or null if no dataroot matches, or no associated NcML.

getPathMatcher

public PathMatcher getPathMatcher()

makeDebugActions

public void makeDebugActions()