List the files in the download cache

qes_cache_info() lists the data files and documents that qesR has kept in its download cache, with the study each belongs to. It only reads the cache directory: it makes no network request and creates nothing.

Usage

qes_cache_info()

Value

A data frame with one row per cached file: study, file_id, md5, bytes, retrieved (modification time), kind (always "file") and path. Attributes mode (the cache mode) and dir (the cache directory, NA in mode "none"). The data frame has class c("qes_cache_info", "data.frame") and prints compactly: the mode, directory and total size once, then each file with its size and its path relative to the cache directory; the path column itself is absolute, and as.data.frame() gives every column. A subset of its columns is a plain data frame.

En français : une ligne par fichier en cache, de classe c("qes_cache_info", "data.frame"). L'affichage donne une fois le mode, le dossier et la taille totale, puis chaque fichier avec sa taille et son chemin relatif au dossier du cache ; la colonne path reste absolue, et as.data.frame() donne toutes les colonnes.

Where files are kept

qesR keeps each downloaded file under the name <file_id>-<md5>.<ext>, taken from its catalog entry, after checking it against the catalog md5. Where depends on the option qesR.cache (or the environment variable QESR_CACHE):

"session" (default)

a qesR folder in tempdir(), deleted when R exits. Nothing is written outside the session's temporary directory.

"disk"

tools::R_user_dir("qesR", "cache"), kept between sessions. qesR creates it only when you choose this mode, and says so.

"none"

nothing is kept: each download goes to a new temporary folder.

Setting qesR.cache_dir (or QESR_CACHE_DIR) to an existing directory keeps files there instead, and implies "disk" unless qesR.cache says otherwise. qesR then works in a qesR subfolder that it creates and marks, and never touches the other files of that directory.

A file you download yourself in a browser (for example when a server refuses automated requests; see qesR-package) can be put in the cache under the name the error message gives: qesR uses it once its md5 matches the catalog.

See also

qes_cache_clear() to delete cached files.

Other cache: qes_cache_clear()

Examples

info <- qes_cache_info()
attr(info, "mode")
#> [1] "disk"
attr(info, "dir")
#> [1] "/home/runner/.cache/qesR-site/qesR"