Download DAB APIs: Introduction - Group on Earth Observations

Data Providers side event
7 November 2016, St. Petersburg
GEO DAB APIs: Introduction
Stefano Nativi
Mattia Santoro
(CNR-IIA and ESSI-lab)
Agenda
• GEOSS, GCI, and GEO DAB
• GEOSS Downstream services and the GEO DAB APIs
– API types
– Common abstract Ontology
– Different Implementations
• Views
GEOSS
end-Users
DOWNSTREAM
GEOSSApplications
Applications
GEOSS
GEOSS
Applications
GEOSS Applications
GEOSS
Web Portal
GEOSS Application
Developers
(intermediate Users)
GEOSS Common Infrastructure
APIs
MIDSTREAM
Mediation modules
Enterprise
System 1
….
Enterprise
System 1
Enterprise
System 2
System
Enterprise
4
System 3
….
UPSTREAM
SBA 1
Enterprise
System 3
System 2
Enterprise
System 2
Enterpris System
4
e System
1
Enterpris
e System
K
SBA 2
….
Enterprise
System j
Enterprise
System System 3
Enterprise 4
GEOSS Providers
….
Enterprise
System Z
SBA 8
[email protected]



[email protected]
GEO DAB APIs
Different APIs for serving diverse Application development use cases
(environments)
 A set of standard Web service interfaces
• e.g. OGC service interfaces, CKAN, OAI-PMH, FTP, etc.
Application A
(services Consumer)

Interfaces
Application B
(services Provider)
GEO DAB APIs
A set of APIs for software developers

Client side APIs:

Server side APIs:
– (high-level) JavaScript library
– … . (Python)

– REST/JSON APIs
– OpenSearch APIs
– ….

API conceptual model (ontology)
Brokering concepts
«Broker»
View
setOfConstraints
Resources Provision concepts
«Broker»
DAB
+mediator
virtualizes
+server
«Provider»
Source
1..*
+Discovery&Access interface
+Publisher
shares
providesAccessTo
+ResultSet
1..*
+AccesibleObject
1..*
Resource
Resource Set
1..*
+AccessedObject
representedBy
«Clause»
Access Parameter
+TransferredEelement
1..*
Representation
[email protected]
JavaScript implementation (Client-side APIs)
+builtResource
+constructor
«GI_Node»
DAB
+ discover() :ResultSet
+ view() :Consumer-defined View
+ getSources() :Sources
«GI_Node»
Source
Sources
1..*
0..*
instancies
Utility concepts
instancies
+constructor
0..*
«utility»
Paginator
ResultSet
navigatedBy
0..1
+builtObject
+ next()() :void
OperatesOn
«GI_Node»
Consumer-defined
View
+ discover() :void
+ getSources() :void
1..*
«GI_Node»
Resource
+accessibleResource
+ download(RepresentationParameters) :ListOfLayers 1..*
lists
representedBy
1..*
«Representation»
Layer
[email protected]
«Clause»
Representation
Parameters
«utility»
Page
REST implementation (Server-side APIs)
Get the list of
brokered Sources
«Resource»
Sources
+ GET() :ListOfDatasetDescription GET
Get the list of
brokered Datasets
«Resource»
Datasets
DatasetDescription
POST
-
+ GET(DatasetID) :DatasetDescription
+ POST(FilterClauses) :ListofDatasetDescription
GET
+ POST(ViewID, FilterClauses) :ListofDatasetDescription
id :ID
title :Title
abstract :Abstract
.... :....
Get the metadata
of a given Dataset
brokered
«dataType»
Dataset Content Parameters
«Resource»
Dataset Content
-
GET(DatasetID) :Dataset Content Parameters
GET
GET(DatasetContentParameters, DatasetID) :DatasetContent
Get a Dataset content
[email protected]
+
+
+
GET(UserID) :ListOfViews
POST(UserID, ViewParameters) :View
DELETE(UserID, ViewID) :void
Get the list of Views
defined by a Provider
GET
POST
DELETE
Get the list of parameters for
accessing Dataset content
+
+
«Resource»
Provider-defined Views
«dataType»
contentCRS :CRS
Envelope :BBOX
envelopeCRS :CRS
format :MIME
spatialResolutions :SpatialResolutions
timePeriod :Interval
Create a View
defined by a Provider
Delete a View
defined by a Provider
OGC WxS (Web Service Interfaces)
ResultSet
contains
returns
1..*
«Web Serice Interface»
Access Service
+
+
+
getCapabilities() :void
describeResource() :void
getResource() :void
Resource
-
metadata :ContentMetadata
+accessAgent
representedBy
1..*
Representation
+downloadedRepresentation
1..* AccessParameters
[email protected]
format :MIMEType
crs :CRSType
envelope :BBOXType
GEOSS View(s)
• Definition:
– Subset of the whole GEOSS resources defined by
applying, via the DAB, a set of clauses
• Discovery clauses (e.g. spatial envelope,
keywords, sources, etc.)
• Access clauses (e.g. data format, access
protocol, CRS, etc.)
Provider-defined View –i.e. Server-side APIs
Consumer-defined View –i.e. Client-side APIs


A simple web-based
tool to define and
manage GEOSS
Views
Virtual Workshop
• A virtual workshop was organized to demonstrate
how to use GEO DAB APIs
• Two sessions:
– Description of APIs: which service interfaces are
supported, which extension parameters, etc.
– Hands-on: how to define views and use APIs in
client applications
Thank you !
15
OGC WCS (Web Service Interfaces)
DiscoveryParameters
ResultSet
discovers
1
«Web Serice Interface»
Discovery Service
contains
+ getCapabilities() :CapabilitiesType
+ getRecords(QueryClausesType) :ResultSetType
+ getRecordbyID(IDType) :RecordType
1..*
Resource
-
[email protected]
metadata :RecordMetadataType