Request cancelation feature

This commit modifies the signature of the `Progress` callback
so that its return value will indicate whether the request shall
continue to be processed by returning `true`, or if it shall
be aborted by returning `false`. Such modification will allow
one to cancel an ongoing request before it has completed.

When migrating, developers should modify there `Progress`
callbacks to always return `true` by default in case there
do not want to benefit from the cancelation feature.

A few unit tests use cases were provided, but anyone should feel
free to provide additional uses cases that they find relevant.
This commit is contained in:
Thomas Tissot 2018-08-06 11:54:52 +02:00
parent cc983be31f
commit 82fc7d5591
2 changed files with 64 additions and 2 deletions

View file

@ -107,7 +107,7 @@ std::pair<std::string, std::string> make_range_header(uint64_t value, Args... ar
typedef std::multimap<std::string, std::string> Params;
typedef std::smatch Match;
typedef std::function<void (uint64_t current, uint64_t total)> Progress;
typedef std::function<bool (uint64_t current, uint64_t total)> Progress;
struct MultipartFile {
std::string filename;
@ -804,7 +804,9 @@ inline bool read_content_with_length(Stream& strm, std::string& out, size_t len,
r += n;
if (progress) {
progress(r, len);
if (!progress(r, len)) {
return false;
}
}
}