jonkeane commented on a change in pull request #10326:
URL: https://github.com/apache/arrow/pull/10326#discussion_r634387573
##########
File path: r/R/dataset.R
##########
@@ -93,8 +93,19 @@ open_dataset <- function(sources,
return(dataset___UnionDataset__create(sources, schema))
}
factory <- DatasetFactory$create(sources, partitioning = partitioning, ...)
- # Default is _not_ to inspect/unify schemas
- factory$Finish(schema, isTRUE(unify_schemas))
+
+ tryCatch(
+ # Default is _not_ to inspect/unify schemas
+ factory$Finish(schema, isTRUE(unify_schemas)),
+ error = function (e) {
+ msg <- conditionMessage(e)
+ if(grep("Parquet magic bytes not found in footer", msg)){
+ stop("Looks like these are not parquet files, did you mean to specify
a 'format'?", call. = FALSE)
+ } else {
+ stop(e)
Review comment:
Does this `stop()` return the call trace now?
##########
File path: r/R/dataset.R
##########
@@ -93,8 +93,19 @@ open_dataset <- function(sources,
return(dataset___UnionDataset__create(sources, schema))
}
factory <- DatasetFactory$create(sources, partitioning = partitioning, ...)
- # Default is _not_ to inspect/unify schemas
- factory$Finish(schema, isTRUE(unify_schemas))
+
+ tryCatch(
+ # Default is _not_ to inspect/unify schemas
+ factory$Finish(schema, isTRUE(unify_schemas)),
+ error = function (e) {
+ msg <- conditionMessage(e)
+ if(grep("Parquet magic bytes not found in footer", msg)){
+ stop("Looks like these are not parquet files, did you mean to specify
a 'format'?", call. = FALSE)
Review comment:
I can see arguments on both sides of this: would it be helpful to
include the original error message as well as our new nicer one?
On the one hand: it's more content and content that some (most?) won't have
the context to know what to do with, but on the other it makes clear what the
message is form the c++ if someone is familiar with that or does have some
reason to suspect that the parquet files are parquet, but were mangled it would
tell them that a bit more clearly.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
