4 ms·

I think I get the concept (and it's interesting); but I'm a bit baffled by the terminology: > That led me to the idea of "spouts" and "bolts" – a spout produce

by jtheory 12y ago

I think I get the concept (and it's interesting); but I'm a bit baffled by the terminology: > That led me to the idea of "spouts" and "bolts" – a spout produces brand new streams, and a bolt takes in streams as input and produces streams as output. Spout I can grasp; why "bolt"? Why these two, together? I'd have really appreciated an extra sentence or two here as to why he chose these terms -- naming is so crucial, and the fact that both "spouts" and "bolts" sound like sources/producers to me (one of water, another of electricity...?) made it harder to grasp how Storm works.

nemothekid 12y ago
Bolt here probably references thunderbolt, and they both references (rain)storms.
- jtheory 12y ago
  That was my assumption; but if you're going to name parts of your system after natural phenomena, you have to choose ones that make some sense, not just names out of a hat that are vaguely in the same domain. "Spout" makes sense as something that's a source of a stream. I haven't been able to figure out the metaphor for "bolt" at all, particularly as something that processes water (stream/spout...) in some way.
siddboots 12y ago
I always assumed that "bolt" refers to the threaded fasteners, not electrical bolts. The analogy they are going for is that they are the components responsible for "bolting" spouts together (although, the mixing of metaphors bothers me a little bit... why are we using bolts to fasten fluids together?) To be super clear about it, a "topology" in Storm is a directed acyclical graph. The nodes are called "bolts" and the edges are called "spouts".
- dwenzek 12y ago
  > a "topology" in Storm is a directed acyclical graph. The nodes are called "bolts" and the edges are called spouts" Not really. Edges are streams and nodes are either spouts or bolts. Spouts have no predecessors and inject external data into the system. Bolts gather one or more input streams and produce zero or more output streams. These names are a bit confusing, but only during the very first steps of a project. Quickly every developers grasp the concepts. I have nevertheless a concern regarding spouts and bolts. In practice, when a topology is refactored, bolts have frequently to be transformed into spouts. This occurs when a topology is split in two to ease deployment; and when a persistent queue is added along a stream. This highlights that the distinction between spouts and bolts is bit artificial.
plainlanguage 12y ago
Spout? Bolt? Firehose? No wonder confusion reigns within and especially outside programmers' worlds. I think I'll bring the campaign for plain English to meetings and ask programmers and marketing people to leave their Gibson paperbacks at the door. Everything doesn't have to sound like a new script for Keanu Reeves. Jeezuz. Call a spade a spade.

by jtheory 12y ago

nemothekid 12y ago

Bolt here probably references thunderbolt, and they both references (rain)storms.

jtheory 12y ago
That was my assumption; but if you're going to name parts of your system after natural phenomena, you have to choose ones that make some sense, not just names out of a hat that are vaguely in the same domain. "Spout" makes sense as something that's a source of a stream. I haven't been able to figure out the metaphor for "bolt" at all, particularly as something that processes water (stream/spout...) in some way.

siddboots 12y ago

I always assumed that "bolt" refers to the threaded fasteners, not electrical bolts. The analogy they are going for is that they are the components responsible for "bolting" spouts together (although, the mixing of metaphors bothers me a little bit... why are we using bolts to fasten fluids together?) To be super clear about it, a "topology" in Storm is a directed acyclical graph. The nodes are called "bolts" and the edges are called "spouts".

dwenzek 12y ago
> a "topology" in Storm is a directed acyclical graph. The nodes are called "bolts" and the edges are called spouts" Not really. Edges are streams and nodes are either spouts or bolts. Spouts have no predecessors and inject external data into the system. Bolts gather one or more input streams and produce zero or more output streams. These names are a bit confusing, but only during the very first steps of a project. Quickly every developers grasp the concepts. I have nevertheless a concern regarding spouts and bolts. In practice, when a topology is refactored, bolts have frequently to be transformed into spouts. This occurs when a topology is split in two to ease deployment; and when a persistent queue is added along a stream. This highlights that the distinction between spouts and bolts is bit artificial.

plainlanguage 12y ago

Spout? Bolt? Firehose? No wonder confusion reigns within and especially outside programmers' worlds. I think I'll bring the campaign for plain English to meetings and ask programmers and marketing people to leave their Gibson paperbacks at the door. Everything doesn't have to sound like a new script for Keanu Reeves. Jeezuz. Call a spade a spade.