cql2_helpers: CQL2 helper function

In rstac: Client Library for SpatioTemporal Asset Catalog

CQL2 helper function

Description

These are helper functions to easy construction CQL2 expressions. These functions are not meant to be used in expressions and they must be escaped using ⁠{{⁠ to be evaluated before request.

Usage

cql2_bbox_as_geojson(bbox)

cql2_date(x)

cql2_timestamp(x)

cql2_interval(start = "..", end = "..")

Arguments

bbox	a numeric containing a bbox with c(xmin, ymin, xmax, ymax).
x, start, end	a character string containing valid date or timestamp.

Details

• cql2_bbox_as_geojson(): used to convert bounding box (bbox) to a GeoJSON object to be used as argument of CQL2 spatial operators.

• cql2_date(), cql2_timestamp(), and cql2_interval(): create temporal literal values to be passed into CQL2 expressions.

Value

• cql2_bbox_as_geojson(): GeoJSON object.

• cql2_date(), cql2_timestamp(), and cql2_interval(): internal rstac expressions representing temporal values.

Examples

## Not run: 
bbox <- c(-122.2751, 47.5469, -121.9613, 47.7458)

cql2_json(
    collection == "landsat-c2-l2" &&
      t_intersects(datetime, {{
        cql2_interval("2020-12-01", "2020-12-31")
      }}) &&
      s_intersects(geometry, {{
        cql2_bbox_as_geojson(bbox)
      }})
  )

## End(Not run)

rstac documentation built on Sept. 11, 2024, 7:03 p.m.