The goal of VicmapR is to provide functions to easily access Victorian Government spatial data through their WFS (Web Feature Service). VicmapR leverages code and a lazy querying approach developed by Teucher et al. (2021) for the {bcdata} R package, which allows for a responsive and precise querying process.
You can install the released version from CRAN with:
install.packages("VicmapR")Or you can install the the development version from GitHub with:
# install.packages("remotes")
remotes::install_github("JustinCally/VicmapR")Currently, the ability to use accurate geometric filters using
VicmapR requires GDAL > 3.0. To see how to upgrade your
version of GDAL and link it to the sf package visit: https://r-spatial.github.io/sf/#installing
library(sf)
#> Warning: package 'sf' was built under R version 4.1.2
#> Linking to GEOS 3.9.1, GDAL 3.4.0, PROJ 8.1.1; sf_use_s2() is TRUE
sf::sf_extSoftVersion()
#> GEOS GDAL proj.4 GDAL_with_GEOS USE_PROJ_H
#> "3.9.1" "3.4.0" "8.1.1" "true" "true"
#> PROJ
#> "8.1.1"library(VicmapR)
#>
#> Attaching package: 'VicmapR'
#> The following object is masked from 'package:stats':
#>
#> filter
# Check to see if the geoserver is working. It will error if it is not working
check_geoserver()
#> [1] TRUE
listLayers(pattern = "trees", ignore.case = T)
#> Name
#> 1 datavic:WATER_ISC2010_LARGE_TREES
#> Title
#> 1 2010 Index of Stream Condition - Large Trees polygon featuresAs of VicmapR version 0.1.0 data is read in using a lazy
evaluation method with the convenience of pipe operators
(%>%). A lot of the methods and code have already been
written for a similar package (bcdata) that downloads data
from the British Columbia WFS catalogues. Using a similar approach,
VicmapR allows users to construct a WFS query in a step-wise format. In
doing so a query is reserved until collect() is used on the
vicmap_promise. The example below shows an extensive
example of how the to easily read in spatial data:
# Read in an example shape to restrict our query to using geometric filtering
melbourne <- sf::st_read(system.file("shapes/melbourne.geojson", package="VicmapR"), quiet = T)
# Obtain a promise of what data will be returned for a given layer
vicmap_query(layer = "datavic:VMHYDRO_WATERCOURSE_DRAIN")
#> • Using collect() on this object will return 195432 features and 16
#> • fields
#> • At most six rows of the record are printed here
#> ────────────────────────────────────────────────────────────────────────────────
#> Simple feature collection with 6 features and 15 fields
#> Geometry type: LINESTRING
#> Dimension: XY
#> Bounding box: xmin: 142.7675 ymin: -35.06905 xmax: 143.324 ymax: -35.04559
#> Geodetic CRS: GDA94
#> # A tibble: 6 × 16
#> id PFI UFI FEATURE_TYPE_CO… NAME NAMED_FEATURE_ID ORIGIN
#> <chr> <int> <int> <chr> <chr> <chr> <chr>
#> 1 VMHYDRO_WATERCOU… 8.55e6 2.55e6 watercourse_cha… <NA> <NA> 2
#> 2 VMHYDRO_WATERCOU… 8.55e6 2.55e6 watercourse_cha… <NA> <NA> 2
#> 3 VMHYDRO_WATERCOU… 8.55e6 2.55e6 watercourse_cha… <NA> <NA> 2
#> 4 VMHYDRO_WATERCOU… 8.55e6 2.55e6 watercourse_cha… <NA> <NA> 2
#> 5 VMHYDRO_WATERCOU… 8.55e6 2.55e6 watercourse_cha… <NA> <NA> 2
#> 6 VMHYDRO_WATERCOU… 8.55e6 2.55e6 watercourse_cha… <NA> <NA> 2
#> # … with 9 more variables: CONSTRUCTION <chr>, USAGE <chr>, HIERARCHY <chr>,
#> # FEATURE_QUALITY_ID <int>, CREATE_DATE_PFI <dttm>, SUPERCEDED_PFI <chr>,
#> # CREATE_DATE_UFI <dttm>, OBJECTID <int>, geometry <LINESTRING [°]>
# Build a more specific query and collect the results
vicmap_query(layer = "datavic:VMHYDRO_WATERCOURSE_DRAIN") %>% # layer to query
filter(HIERARCHY == "L") %>% # simple filter for a column
filter(INTERSECTS(melbourne)) %>% # more advanced geometric filter
select(HIERARCHY, PFI) %>%
collect()
#> Note: method with signature 'DBIConnection#character' chosen for function 'dbQuoteIdentifier',
#> target signature 'wfsConnection#ident'.
#> "wfsConnection#ANY" would also be valid
#> Note: method with signature 'DBIConnection#character' chosen for function 'dbQuoteIdentifier',
#> target signature 'wfsConnection#character'.
#> "wfsConnection#ANY" would also be valid
#> Note: method with signature 'DBIConnection#character' chosen for function 'dbQuoteString',
#> target signature 'wfsConnection#character'.
#> "wfsConnection#ANY" would also be valid
#> Simple feature collection with 8 features and 5 fields
#> Geometry type: LINESTRING
#> Dimension: XY
#> Bounding box: xmin: 144.909 ymin: -37.81511 xmax: 144.9442 ymax: -37.78198
#> Geodetic CRS: GDA94
#> # A tibble: 8 × 6
#> id PFI UFI HIERARCHY OBJECTID geometry
#> <chr> <int> <int> <chr> <int> <LINESTRING [°]>
#> 1 VMHYDRO_WATERCOURS… 1.46e7 3.63e7 L 1605003 (144.9365 -37.81511, 144…
#> 2 VMHYDRO_WATERCOURS… 1.46e7 3.63e7 L 1582117 (144.929 -37.81409, 144.…
#> 3 VMHYDRO_WATERCOURS… 1.46e7 3.63e7 L 1582120 (144.9288 -37.81417, 144…
#> 4 VMHYDRO_WATERCOURS… 1.46e7 4.90e7 L 2432411 (144.9403 -37.78253, 144…
#> 5 VMHYDRO_WATERCOURS… 1.75e7 4.90e7 L 2432413 (144.9415 -37.78232, 144…
#> 6 VMHYDRO_WATERCOURS… 1.46e7 4.90e7 L 2432415 (144.9442 -37.78198, 144…
#> 7 VMHYDRO_WATERCOURS… 1.93e7 5.44e7 L 2698790 (144.9287 -37.8033, 144.…
#> 8 VMHYDRO_WATERCOURS… 1.46e7 5.44e7 L 2698805 (144.9201 -37.79069, 144…VicmapR translates numerous geometric filter functions available in the Victorian Government’s WFS Geoserver supports numerous geometric filters:
EQUALSDISJOINTINTERSECTSTOUCHESCROSSESWITHINCONTAINSOVERLAPSDWITHINBEYONDBBOXThese filters can be used within the filter() function
by providing them an object of class sf/sfc/sfg/bbox as
shown above with the melbourne object.
Using options(vicmap.base_url) VicmapR can query data
from other WFS services; while this remains somewhat untested it is
relatively easy to point VicmapR to another WFS url. This option would
need to be set every session to override the base VicmapR url. For
instance, the BOM WFS can be used as follows:
# set the new base url
options(vicmap.base_url = "http://geofabric.bom.gov.au/simplefeatures/ahgf_shcatch/wfs")
# collect a data sample
catchments <- vicmap_query("ahgf_shcatch:AHGFCatchment") %>%
head(10) %>%
collect()Note: Using other Geoserver WFS urls will not necessarily work as expected due to the potential differences in the capabilities of the Geoserver instance
Copyright 2018 Province of British Columbia
Modifications Copyright 2020 Justin Cally
Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at
https://www.apache.org/licenses/LICENSE-2.0.txt
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.