Object cache driver that saves objects using R's native
serialised file format (see
saveRDS) on the
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Path for the store.
Compress the generated file? This saves a small amount of space for a reasonable amount of time.
Mangle keys? If TRUE, then the key is encoded using base64 before saving to the filesystem. See Details.
Default namespace (see
mangle_key argument will run each key that is created
through a "base 64" encoding. This means that keys that include
symbols that are invalid on filesystems (e.g, "/", ":") will be
replaced by harmless characters. The RFC 4648 dialect is used
where "-" and "_" are used for character 62 and 63 (this differs
from most R base64 encoders). This mangling is designed to be
transparent to the user – the storr will appear to store things
with unmangled keys but the names of the stored files will be
Note that the namespace is not mangled (at least not yet) so needs to contain characters that are valid in a filename.
Because the actual file will be stored with mangled names it is
not safe to use the same path for a storr with and without
mangling. So once an rds storr has been created its "mangledness"
is set. Using
mangle_key=NULL uses whatever mangledness
exists (or no mangledness if creating a new storr).
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# Create an rds storr in R's temporary directory: st <- storr_rds(tempfile()) # Store some data (10 random numbers against the key "foo") st$set("foo", runif(10)) st$list() # And retrieve the data: st$get("foo") # Keys that are not valid filenames will cause issues. This will # cause an error: ## Not run: st$set("foo/bar", letters) ## End(Not run) # The solution to this is to "mangle" the key names. Storr can do # this for you: st2 <- storr_rds(tempfile(), mangle_key=TRUE) st2$set("foo/bar", letters) st2$list() st2$get("foo/bar") # Behind the scenes, storr is safely encoding the filenames with base64: dir(file.path(st2$driver$path, "keys", "objects")) # Clean up the two storrs: st$destroy() st2$destroy()