Skip to contents

SC-01 / SC-02: Check columns against the expected schema contract

Source: R/checks_generic.R
check_schema_contract.Rd

Compares the columns present in df against config$expected_columns:

  • SC-01: one "FAIL" result per column present in the file but not listed in expected_columns.

  • SC-02: one "FAIL" result per column listed in expected_columns but absent from the file.

Returns an empty list if expected_columns is not configured.

Usage

check_schema_contract(df, config)

Arguments

df

A data frame with all columns as character vectors (as returned by read_dataset).

config

Named list. Merged configuration as returned by load_config.

Value

A list of dq_result objects. Each schema violation produces one "FAIL" result; a "PASS" result is emitted for each sub-check when no violations are found. Returns an empty list if expected_columns is not configured.

Examples

cfg_dir <- system.file("demonstrations/config", package = "dqcheckr")
cfg  <- load_config("starwars_csv", config_dir = cfg_dir)
path <- system.file("demonstrations/data/starwars.csv", package = "dqcheckr")
df   <- read_dataset(path, cfg)
check_schema_contract(df, cfg)
#> [[1]]
#> [[1]]$check_id
#> [1] "SC-01"
#> 
#> [[1]]$check_name
#> [1] "Unexpected column"
#> 
#> [[1]]$column
#> [1] NA
#> 
#> [[1]]$status
#> [1] "PASS"
#> 
#> [[1]]$observed
#> [1] "No unexpected columns."
#> 
#> [[1]]$threshold
#> [1] NA
#> 
#> [[1]]$message
#> [1] "All file columns are in the expected schema."
#> 
#> 
#> [[2]]
#> [[2]]$check_id
#> [1] "SC-02"
#> 
#> [[2]]$check_name
#> [1] "Missing expected column"
#> 
#> [[2]]$column
#> [1] NA
#> 
#> [[2]]$status
#> [1] "PASS"
#> 
#> [[2]]$observed
#> [1] "All expected columns are present."
#> 
#> [[2]]$threshold
#> [1] NA
#> 
#> [[2]]$message
#> [1] "No expected columns are missing from the file."
#> 
#>