Automatic Generation of WebBased GISDatabase Applications

1
Automatic Generation of Web-Based GIS/Database
Applications

• Nirut Chalainanont
• Junya Sano
• Toshimi Minoura
•  Department of Computer Science
• Oregon State University
• Corvallis, Oregon, 97331-4602
• minoura_at_cs.orst.edu

2
Outline

• Web-based GIS/database applications
• WebGD Framework
• Automatic generation of Web-form scripts
• Automatic generation of map-layer configuration
  files
• Conclusions

3
Enterprise Resource Management

• Enterprise resource management involves
• Inventory management
• Project management
• Issue tracking
• Personnel management
• Accounting
• Client Relationship Management

4
Resource Management Applications with
Location-Based Data

• Transportation
• Water/Sewage
• Electricity
• Gas/Oil
• Freight
• Environmental Resource Management

5
Location-Based Datain Resource Management
Applications

• Project sites
• Facility locations
• Points
• Networks
• Polygons
• Incident sites

6
WebGD Capabilities

• Geographical features can be inserted, queried,
  and deleted from a map interface.
• A map interface and Web-forms can be
  automatically generated.
• Dynamic switching of spatial references is
  supported.

7
WebGD Capabilities (contd)

• GIS data in an area selected by the user can be
  exported as a shapefile.
• A treeview can be automatically created.
• A PDF file containing the map image and data
  retrieved from the database can be created.
• Photo images can be uploaded.

8
Natural Heritage Information System
9
Search and Automatic Zoom In to a Selected
feature
10
Inserting a Property
11
Treeview
12
PDF File Generation
13
Uploading Photo Images
14
Components in a Water Distribution Network

• Water mains
• Pumps
• Lateral lines
• Hydrants
• Valves
• Meters
• Storage Units
• etc.

15
Water Line Network Zoomed-Out View
16
Water Line Network Zoomed-In View
17
Database Schema for a Water Distribution Resource
Management System
18
WebGD Architecture
PHP scripts create the map object and access the
database.
Web Browser
Defines PHP classes for GIS objects.
PHP
Web Server
PHP/MapScript
Provides functions to manage geospatial data
MapServer
PostGIS
Generates map images.
PostgreSQLDatabase
Stores geospatial and business data.
19
PostgreSQL

• The object-relational feature of PostgreSQL
  simplifies manipulation of geographical objects

select gid from sites where geom_col
setSRID(BOX2D(10 20, 80 90)box2d,
6010)) select X(geom_col), Y(geom_col) from
sites where gid 100
20
Dynamic Switching of Spatial References

• World ?Longitude/Latitude
• North America ? Albers Equal Area
• California ?UTM 10 and 11
• Oregon ? Lambert Conformal Conic

21
World in Longitude/Latitude
22
North America in Albers Equal Area
23
Continental United States in Albers Equal Area
24
Oregon in Lambert Conformal Conic
25
WebGD Framework

• A collection of scripts common to all WebGD
  applications
• Customizable with configuration files
• Sever-side scripts written in PHP
• Client-side scripts written in JavaScript
• Some AJAX (Asynchronous JavaScript and XML)
  scripts.

26
Region Configuration

• Map projection
• Unit distance of measurement
• Name of the map file for the region
• Name of the map layer configuration file
• Name of quick view configuration file

27
Region Configuration
28
Map Layer Configuration

• The following information is kept for each legend
  entry
• Spatial reference ID
• Geometry type
• Icon and label for the layer
• Database table associated with the layer
• Actions associated with the layer

29
Map Layer Configuration
30
Quick View Configuration

• The quick view mechanism allows the user
• to go to a predefined area directly
• Spatial reference for each area
• Extent of each area
• Name of each area

31
Quick View Configuration
32
WegGD Application Generator

• WebGD-Gen automatically generates a consistent
  set of Web scripts from configuration files,
  including those for a map interface.
• Configuration files are again automatically
  generated from a relational database schema.
• The cost of application development is greatly
  reduced.

33
Process of Configuration File Generation
meta meta configuration file for table xxx
meta configuration file for table xxx
configuration file for table xxx
34
Process of Web Script Generation
configuration file for table xxx
35
WebGen Configuration File

• search_fields for the search script.
• search_fields, select_fields and
  search_join_tables for the select script
• edit_fields for the edit script
• info_blocks for information script

36
Search Form
Client
Server
1) Search request
2) Search Form
Search Form
3) Search parameters
5) Checked search parameters
4) Errors
37
Select Form
Client
Server
Select Form
5) Checked search parameters
8) Search Results
6) Query
Select
Script
7) Retrieved records
9) Update Record
Edit Script
10) Insert a new Record
Info Script
11) Show Record
Action Script
13) Delete query
12) IDs for delete
38
Edit Form
Server
Client
Select Form
12) Insert/Edit
Edit
Script
13) Insert/Edit
14) Insert/Update/Delete
Edit Form
16) Insert/Update/Delete
Action
15) Error
Script
39
Linked Forms
Department Select Form
Department Search Form
Selected ID
Student Edit Form
Department Edit Form
Course Select Form
40
search_fields

• search_fieldsarray(
• array("column"gt"student_id",
• "label"gt"Student ID",
• "type"gt"numeric",
• "maxlen"gt"40",
• "size"gt"40"),
• array("column"gt"first_name",
• "label"gt"First Name",
• "type"gt"text",
• "maxlen"gt"40",
• "size"gt"40"),
• . . .
• )

41
Configuration for a Map Interface

• WebGD-Gen can generate the statements for
  inserting, searching, and deleting geographical
  features from the following lines in a
  configuration file

web_gd MULTIPOLYGON layer_name
grp_eo_py geometry_column the_geom
gid_column gid db_table_srid 6010
42
Advantages of the WebGD Approach

• Since the Web scripts for database access are
  automatically generated, the database can contain
  hundreds of tables.
• The database can be incrementally and iteratively
  designed.
• The cost and time of creating an advanced
  Web-based GIS/database application can be greatly
  reduced.

43
Conclusions
Web-based GIS/database applications have a great
potential for enterprise resource management
applications.

• Users can add geographical features and
  associated data with Web browsers.
• A WebGD application can be automatically
  generated.
• The whole world or the entire USA can be
  seamlessly covered.

44
Acknowledgement

• Dileep Arur
• Haris Gunadi
• Surya Halim
• Hong Gyu Han
• Mariko Imaeda
• Junya Sano

• Akash Sharma
• Hiroshi Tashiro
• Naroot Wanalertlak
• Paphun Wangmutitakul
• Teerawat Wuttiwat

45
URL
http//yukon.een.orst.edu/index0.html