Generate URLs for WaPOR/AgERA5 Resources

Generates download URLs for WaPOR or AgERA5 raster data from the FAO GISMGR API based on variable name, region, and time period.

Usage

wapor_generate_urls(variable, l3_region = NULL, period = NULL)

Arguments

variable

Character. Variable name following WaPOR/AgERA5 naming convention (e.g., "L1-AETI-D", "L2-NPP-M", "AGERA5-ET0-E"). The format is {Level}-{Variable}-{TemporalResolution} where:

• Level: L1, L2, L3 (WaPOR) or AGERA5

• Variable: AETI, E, I, NPP, PCP, T, GBWP, NBWP, ET0, TMIN, TMAX, etc.

• Temporal: D (dekadal), M (monthly), A (annual), E (daily)

l3_region

Character. Optional L3 region code for Level 3 data (e.g., "AWA" for Awash Basin). Only applicable for L3 variables.

period

Character vector of length 2. Optional date range as c(start_date, end_date) in "YYYY-MM-DD" format.

Value

Character vector of download URLs, sorted chronologically.

Details

Results are cached using memoization so that repeated calls with identical arguments within the same session avoid redundant API requests.

Examples

if (FALSE) { # \dontrun{
# Get URLs for dekadal evapotranspiration in January 2023
urls <- wapor_generate_urls(
  variable = "L1-AETI-D",
  period = c("2023-01-01", "2023-01-31")
)

# Get URLs for L3 data in Awash Basin
urls <- wapor_generate_urls(
  variable = "L3-AETI-D",
  l3_region = "AWA",
  period = c("2023-01-01", "2023-03-31")
)

# Get AgERA5 reference evapotranspiration
urls <- wapor_generate_urls(
  variable = "AGERA5-ET0-E",
  period = c("2023-06-01", "2023-06-30")
)
} # }