R/get-network.R

In ITSLeeds/osmextractr: Download and Import Open Street Map Data Extracts

#' Import transport networks used by a specific mode of transport
#'
#' This function is a wrapper around [oe_get()] and can be used to import a road
#' network given a `place` and a mode of transport. Check the Details for a
#' precise description of the procedures used to filter the OSM ways according
#' to each each mode of transport.
#'
#' @inheritParams oe_get
#' @param mode A character string of length one denoting the desired mode of
#'   transport. Can be abbreviated. Currently `cycling` (the default), `driving`
#'   and `walking` are supported.
#' @param ... Additional arguments passed to [oe_get()] such as `boundary` or
#'   `force_download`.
#'
#' @return An `sf` object.
#' @export
#'
#' @details The definition of usable transport network was taken from the Python
#'   packages
#'   [osmnx](https://raw.githubusercontent.com/gboeing/osmnx/refs/heads/main/osmnx/_overpass.py) and
#'   [pyrosm](https://pyrosm.readthedocs.io/en/latest/) and several other
#'   documents found online, i.e.
#'   <https://wiki.openstreetmap.org/wiki/OSM_tags_for_routing/Access_restrictions>,
#'    <https://wiki.openstreetmap.org/wiki/Key:access>. See also the discussion
#'   in <https://github.com/ropensci/osmextract/issues/153>.
#'
#'   The `cycling` mode of transport (i.e. the default value for `mode`
#'   parameter) selects the OSM ways that meet the following conditions:
#'
#'   - The `highway` tag is not missing;
#'   - The `highway` tag is not equal to `abandoned`, `bus_guideway`, `byway`,
#'   `construction`, `corridor`, `elevator`, `fixme`, `escalator`, `gallop`,
#'   `historic`, `no`, `planned`, `platform`, `proposed`, `raceway` or
#'   `steps`;
#'   - The `highway` tag is not equal to `motorway`, `motorway_link`,
#'   `footway`, `bridleway` or `pedestrian` unless the tag `bicycle` is equal
#'   to `yes`, `designated`, `permissive` or `destination` (see
#'   [here](https://wiki.openstreetmap.org/wiki/Bicycle#Bicycle_Restrictions)
#'   for more details);
#'   - The `access` tag is not equal to `private` or `no` unless `bicycle` is
#'   equal to `yes`, `permissive` or `designated` (see #289);
#'   - The `bicycle` tag is not equal to `no`, `use_sidepath`, `private`, or
#'   `restricted`;
#'   - The `service` tag does not contain the string `private` (i.e.
#'   `private`, `private_access` and similar);
#'
#'   The `walking` mode of transport selects the OSM ways that meet the
#'   following conditions:
#'
#'   - The `highway` tag is not missing;
#'   - The `highway` tag is not equal to `abandoned`, `bus_guideway`,
#'   `byway`, `construction`, `corridor`, `elevator`, `fixme`,
#'   `escalator`, `gallop`, `historic`, `no`, `planned`, `platform`, `proposed`,
#'   `raceway`, `motorway` or `motorway_link`;
#'   - The `highway` tag is not equal to `cycleway` unless the `foot` tag is
#'   equal to `yes`;
#'   - The `access` tag is not equal to `private` or `no` unless `foot` is
#'   equal to `yes`, `permissive`, or `designated` (see #289);
#'   - The `foot` tag is not equal to `no`, `use_sidepath`, `private`, or
#'   `restricted`;
#'   - The `service` tag does not contain the string `private`
#'   (i.e. `private`, `private_access` and similar).
#'
#'   The `driving` mode of transport selects the OSM ways that meet the
#'   following conditions:
#'
#'   - The `highway` tag is not missing;
#'   - The `highway` tag is not equal to `abandoned`,
#'   `bus_guideway`, `byway`, `construction`, `corridor`, `elevator`, `fixme`,
#'   `escalator`, `gallop`, `historic`, `no`, `planned`, `platform`, `proposed`,
#'   `cycleway`, `pedestrian`, `bridleway`, `path`, or `footway`;
#'   - The `access` tag is not equal to `private` or `no` unless `motor_vehicle` is
#'   equal to `yes`, `permissive`, or `designated` (see #289);
#'   - The `service` tag does not contain the string `private` (i.e. `private`,
#'   `private_access` and similar).
#'
#'   Feel free to create a new issue in the [github
#'   repo](https://github.com/ropensci/osmextract) if you want to suggest
#'   modifications to the current filters or propose new values for alternative
#'   modes of transport.
#'
#' @seealso [oe_get()]
#'
#' @examples
#' # Copy the ITS file to tempdir() to make sure that the examples do not
#' # require internet connection. You can skip the next 4 lines (and start
#' # directly with oe_get_keys) when running the examples locally.
#'
#' its_pbf = file.path(tempdir(), "test_its-example.osm.pbf")
#' file.copy(
#'   from = system.file("its-example.osm.pbf", package = "osmextract"),
#'   to = its_pbf,
#'   overwrite = TRUE
#' )
#'
#' # default value returned by OSM
#' its = oe_get(
#'   "ITS Leeds", quiet = TRUE, download_directory = tempdir()
#' )
#' plot(its["highway"], lwd = 2, key.pos = 4, key.width = lcm(2.75))
#' # walking mode of transport
#' its_walking = oe_get_network(
#'   "ITS Leeds", mode = "walking",
#'   download_directory = tempdir(), quiet = TRUE
#' )
#' plot(its_walking["highway"], lwd = 2, key.pos = 4, key.width = lcm(2.75))
#' # driving mode of transport
#' its_driving = oe_get_network(
#'   "ITS Leeds", mode = "driving",
#'   download_directory = tempdir(), quiet = TRUE
#' )
#' plot(its_driving["highway"], lwd = 2, key.pos = 4, key.width = lcm(2.75))
#'
#' # Remove .pbf and .gpkg files in tempdir
#' oe_clean(tempdir())
oe_get_network = function(
  place,
  mode = c("cycling", "driving", "walking"),
  ...
) {
  # Load the relevant oe_get options
  mode = match.arg(mode)
  oe_get_options = switch(
    mode,
    cycling = load_options_cycling(place),
    driving = load_options_driving(place),
    walking = load_options_walking(place)
  )

  # Check the other arguments supplied by the user
  dots_args = list(...)
  oe_get_options = check_args_network(dots_args, oe_get_options)

  # Run oe_get
  do.call(oe_get, oe_get_options)
}

# The following functions are used to load several ad-hoc vectortranslate
# options according to a specific mode of transport. The choices are documented
# in oe_get_network() and are based on the following documents:
# https://wiki.openstreetmap.org/wiki/OSM_tags_for_routing/Access_restrictions
# and https://wiki.openstreetmap.org/wiki/Key:access plus the discussion in
# https://github.com/ropensci/osmextract/issues/153 and https://github.com/udsleeds/openinfra/issues/32

# According to the first document mentioned above (i.e. the OSM tags for
# routing), there are some default values that are not official nor generally
# accepted but have support among many mappers. More precise options are defined
# by other tags. See also: https://wiki.openstreetmap.org/wiki/Bicycle#Bicycle_Restrictions

# WARNING: Starting from GDAL 3.10, an expression like "foo NOT IN ('bar')"
# evaluates as false, while previously it would evaluate as true. Therefore, in
# the following code, when building the -where clause, we need to be explicit
# and include possible NULL values in the expression. See also the discussion in
# #298 and the fix implemented by @rouault. See also
# https://github.com/OSGeo/gdal/blob/779871e56134111d61f1fe2859b8d19f8f04fcdf/MIGRATION_GUIDE.TXT#L4
# for official docs.

load_options_cycling = function(place) {
  list(
    place = place,
    layer = "lines",
    extra_tags = c("access", "bicycle", "service"),
    vectortranslate_options = c(
    "-where", "
    (highway IS NOT NULL)
    AND
    (highway IS NULL OR highway NOT IN (
    'abandoned', 'bus_guideway', 'byway', 'construction', 'corridor', 'elevator',
    'fixme', 'escalator', 'gallop', 'historic', 'no', 'planned', 'platform',
    'proposed', 'raceway', 'steps'
    ))
    AND
    (highway IS NULL OR highway NOT IN ('motorway', 'motorway_link', 'footway', 'bridleway',
    'pedestrian') OR bicycle IN ('yes', 'designated', 'permissive', 'destination')
    )
    AND
    (access IS NULL OR (access NOT IN ('private', 'no') OR bicycle IN ('yes', 'permissive', 'designated')))
    AND
    (bicycle IS NULL OR bicycle NOT IN ('private', 'no', 'use_sidepath', 'restricted'))
    AND
    (service IS NULL OR service NOT ILIKE 'private%')
    "
    )
  )
}

# See also https://wiki.openstreetmap.org/wiki/Key:footway and
# https://wiki.openstreetmap.org/wiki/Key:foot
load_options_walking = function(place) {
  list(
    place = place,
    layer = "lines",
    extra_tags = c("access", "foot", "service"),
    vectortranslate_options = c(
    "-where", "
    (highway IS NOT NULL)
    AND
    (highway IS NULL OR highway NOT IN ('abandoned', 'bus_guideway', 'byway', 'construction', 'corridor', 'elevator',
    'fixme', 'escalator', 'gallop', 'historic', 'no', 'planned', 'platform', 'proposed', 'raceway',
    'motorway', 'motorway_link'))
    AND
    (highway IS NULL OR highway <> 'cycleway' OR foot IN ('yes', 'designated', 'permissive', 'destination'))
    AND
    (access IS NULL OR (access NOT IN ('private', 'no') OR foot IN ('yes', 'permissive', 'designated')))
    AND
    (foot IS NULL OR foot NOT IN ('private', 'no', 'use_sidepath', 'restricted'))
    AND
    (service IS NULL OR service NOT ILIKE 'private%')
    "
    )
  )
}

load_options_driving = function(place) {
  list(
    place = place,
    layer = "lines",
    extra_tags = c("access", "service", "oneway", "motor_vehicle"),
    vectortranslate_options = c(
    "-where", "
    (highway IS NOT NULL)
    AND
    (highway IS NULL OR highway NOT IN (
    'abandoned', 'bus_guideway', 'byway', 'construction', 'corridor', 'elevator',
    'fixme', 'escalator', 'gallop', 'historic', 'no', 'planned', 'platform',
    'proposed', 'cycleway', 'pedestrian', 'bridleway', 'path', 'footway',
    'steps'
    ))
    AND
    (access IS NULL OR (access NOT IN ('private', 'no') OR motor_vehicle IN ('yes', 'permissive', 'designated')))
    AND
    (service IS NULL OR service NOT ILIKE 'private%')
    "
    )
  )
}

# The following function is used to merge the vectortranslate options set by the
# mode of transport and the other oe_get options set by the user.
check_args_network = function(dots_args, oe_get_options) {
  # Check if the user set any argument in the call. If not, just return.
  if (length(dots_args) == 0L) {
    return(oe_get_options)
  }

  # Check the layer argument. At the moment we support only the lines layer
  if (!is.null(dots_args[["layer"]]) && dots_args[["layer"]] != "lines") {
    warning(
      "oe_get_network() works only with lines layer. Ignoring other values",
      call. = FALSE
    )
    # Remove the layer
    dots_args[["layer"]] = NULL
  }

  # Check the extra_tags argument and add all necessary values
  if (!is.null(dots_args[["extra_tags"]])) {
    oe_get_options[["extra_tags"]] = unique(
      c(oe_get_options[["extra_tags"]], dots_args[["extra_tags"]])
    )
    dots_args[["extra_tags"]] = NULL
  }

  # Check the vectortranslate_options argument and the -where keyword
  if (!is.null(dots_args[["vectortranslate_options"]])) {
    if ("-where" %in% dots_args[["vectortranslate_options"]]) {
      # Raise an error since -where arg must be set by the function
      oe_stop(
        .subclass = "oe_get_network-cannotUseWhere",
        message = paste0(
          "The vectortranslate_options inside oe_get_network() cannot be used ",
          "to define a query with the -where argument. Use the query argument"
        )
      )
    }
    # Otherwise append the two vectors
    oe_get_options[["vectortranslate_options"]] = c(
      oe_get_options[["vectortranslate_options"]], dots_args[["vectortranslate_options"]]
    )

    # Delete the value
    dots_args[["vectortranslate_options"]] = NULL
  }

  # Bind the two lists
  oe_get_options = c(oe_get_options, dots_args)

  # Return
  oe_get_options
}