RedisSessionStore - hkeys

[lvnar]

I cannot use de hkeys function on redis. There is an exception when I run it:

core.exception.AssertError@../.dub/packages/vibe-d-0.7.27/vibe-d/source/vibe/db/redis/redis.d(1150): Assertion failure
Program exited with code 1

Any idea?

[etcimon]

That's because you used a RedisReply!T and didn't consume it completely in a previous connection. Make sure you do popFront() on each field until .front is null

[lvnar]

I'm using popFront(), while(x.hasNext), but the error is still there when I try to use RedisReply again.

[etcimon]

Do you have a code sample?

[lvnar]

`auto scan = redisDB.keys(pattern);

while(scan.hasNext) {
keys ~= scan.front;
scan.popFront();
}
foreach (string key; keys) {
try {
keyValue = [key, redisDB.get(key)];
result ~= keyValue;
}
catch (Exception e){
auto res = redisDB.hgetAll(key);
while(res.hasNext){
res.popFront();
}
}
}`

There, on hgetAll is where the exception appears:

core.exception.AssertError@../.dub/packages/vibe-d-0.7.27/vibe-d/source/vibe/db/redis/redis.d(1150): Assertion failure

[etcimon]

You should use foreach(key; scan) instead it's less error prone

[etcimon]

The problem is that your first RedisReply from the keys call is still using the connection while you try to acquire the connection in a second RedisReply from the hgetAll call. You can simply enclose the first part in a scope like this:

{
   auto scan = redisDB.keys(pattern);

   while(scan.hasNext) {
      keys ~= scan.front;
      scan.popFront();
   }
}

[etcimon]

You should avoid making calls that can throw inside catch clauses, and make sure you don't use try/catch as a replacement for if/else because it takes a while to populate a stack trace.

[s-ludwig]

I've opened a fix (#1416), which is a slightly more refined version of the fix in #1396. It doesn't have a test case, yet. I'll add that before pulling.

[lvnar]

Thaks for the advices, were useful.