spod_check_files: Check cached files consistency against checksums from S3

In spanishoddata: Get Spanish Origin-Destination Data

Check cached files consistency against checksums from S3

Description

WARNING: The checks may fail for May 2022 data and for some 2025 data, as the remote cheksums that are used for checking the file consistency are incorrect. We are working on solving this in future updates, for now, kindly rely on the built-in file size checks of spod_download, spod_get, and spod_convert. This function checks downloaded data files whether they are consistent with their checksums in Amazon S3 by computing ETag for each file. This involves computing MD5 for each part of the file and concatenating them and computing MD5 again on the resulting concatenated MD5s. This may take very long time if you check all files, so use with caution.

Usage

spod_check_files(
  type = c("od", "origin-destination", "os", "overnight_stays", "nt", "number_of_trips"),
  zones = c("districts", "dist", "distr", "distritos", "municipalities", "muni",
    "municip", "municipios", "lua", "large_urban_areas", "gau", "grandes_areas_urbanas"),
  dates = NULL,
  data_dir = spod_get_data_dir(),
  quiet = FALSE,
  ignore_missing_dates = FALSE,
  n_threads = 1
)

Arguments

type	The type of data to download. Can be "origin-destination" (or ust "od"), or "number_of_trips" (or just "nt") for v1 data. For v2 data "overnight_stays" (or just "os") is also available. More data types to be supported in the future. See codebooks for v1 and v2 data in vignettes with spod_codebook(1) and spod_codebook(2) (spod_codebook).
zones	The zones for which to download the data. Can be "districts" (or "dist", "distr", or the original Spanish "distritos") or "municipalities" (or "muni", "municip", or the original Spanish "municipios") for both data versions. Additionaly, these can be "large_urban_areas" (or "lua", or the original Spanish "grandes_areas_urbanas", or "gau") for v2 data (2022 onwards).
dates	A character or Date vector of dates to process. Kindly keep in mind that v1 and v2 data follow different data collection methodologies and may not be directly comparable. Therefore, do not try to request data from both versions for the same date range. If you need to compare data from both versions, please refer to the respective codebooks and methodology documents. The v1 data covers the period from 2020-02-14 to 2021-05-09, and the v2 data covers the period from 2022-01-01 to the present until further notice. The true dates range is checked against the available data for each version on every function run. The possible values can be any of the following: For the spod_get() and spod_convert() functions, the dates can be set to "cached_v1" or "cached_v2" to request data from cached (already previously downloaded) v1 (2020-2021) or v2 (2022 onwards) data. In this case, the function will identify and use all data files that have been downloaded and cached locally, (e.g. using an explicit run of spod_download(), or any data requests made using the spod_get() or spod_convert() functions). A single date in ISO (YYYY-MM-DD) or YYYYMMDD format. character or Date object. A vector of dates in ISO (YYYY-MM-DD) or YYYYMMDD format. character or Date object. Can be any non-consecutive sequence of dates. A date range eigher a character or Date object of length 2 with clearly named elements start and end in ISO (YYYY-MM-DD) or YYYYMMDD format. E.g. c(start = "2020-02-15", end = "2020-02-17"); or a character object of the form YYYY-MM-DD_YYYY-MM-DD or YYYYMMDD_YYYYMMDD. For example, ⁠2020-02-15_2020-02-17⁠ or ⁠20200215_20200217⁠. A regular expression to match dates in the format YYYYMMDD. character object. For example, ⁠^202002⁠ will match all dates in February 2020.
data_dir	The directory where the data is stored. Defaults to the value returned by spod_get_data_dir() which returns the value of the environment variable SPANISH_OD_DATA_DIR or a temporary directory if the variable is not set. To set the data directory, use spod_set_data_dir.
quiet	A logical value indicating whether to suppress messages. Default is FALSE.
ignore_missing_dates	Logical. If TRUE, the function will not raise an error if the some of the specified dates are missing. Any dates that are missing will be skipped, however the data for any valid dates will be acquired. Defaults to FALSE.
n_threads	Numeric. Number of threads to use for file verificaiton. Defaults to 1. When set to 2 or more threads, uses future.mirai as a backend for parallelization, resulting in significant (~4x) speedup, unless disk read speed is a bottleneck.

Value

A tibble similar to the output of spod_available_data, but with an extra column local_file_consistent, where TRUE indicates that the file cheksum matches the expected checksums in Amazon S3. Note: some v1 (2020-2021) files were not stored correctly on S3 and their ETag checksums are incorrectly reported by Amazon S3, so their true file sizes and ETag checksums were cached inside the spanishoddata package.

Examples

spod_set_data_dir(tempdir())
spod_download(
 type = "number_of_trips",
 zones = "distr",
 dates = "2020-03-14"
)

# now check the consistency
check_results <- spod_check_files(
  type = "number_of_trips",
  zones = "distr",
  dates = "2020-03-14"
)
all(check_results$local_file_consistent)

spanishoddata documentation built on June 16, 2025, 1:07 a.m.