Explicit consistency in components and ports case in .fbp syntax

[DjebbZ]

Yeah, it might look like un-important, but at least it is to a beginner like me.

In the noflo website, Getting Started page, libraries are all lowercased (like core and math), components are CamelCased (like Output and ReadFile), ports are uppercased (like IN and OUT). In the cli, noflo list . shows libraries lowercased (ok), components CamelCased (ok), and ports lowercased (huh?).

I suggest the cli output should match the fbp syntax (ports uppercased), and all this case stuff should be documented somewhere. What do you think ?

[bergie]

Agreed, it should be:

• Node names (component instances) are CamelCased
• Port names are UPPERCASE (like in .fbp)

[trustmaster]

How about Flowhub and interacting with other runtimes? Should port names be always uppercase? Or lowercase/camelCase and uppercase in FBP only? I've encountered case-sensitivity problems while using Flowhub and implementing GoFlow runtime (which is case-sensitive).

[paulyoung]

Very good point. It seems like ComponentLoader may be a better place to do this.

[paulyoung]

The CLI currently relies on ComponentLoader::listComponents for its output. Internally ComponentLoader::load relies on the same instance variable so perhaps loading would need to become case-insensitive (i.e. convert to lowercase on both sides when matching strings).

[paulyoung]

I introduced a new method since using the existing one complicated things when loading components.

It seems odd to me that this is part of the ComponentLoader class.

[paulyoung]

If anyone can offer better insight, I'm happy to go a different direction.

[trustmaster]

Seems like a subject for another FBP mailing list dispute. I personally prefer case sensitive camelCase port names as it leaves less space for accidents and supports multiWordNames if necessary.

[paulyoung]

When the tests were initially failing, READDOCUMENT did look a bit weird.

[subtleGradient]

I vote for camelCasePortNames.

[trustmaster]

This is my proposal for this issue:

• Make port names case-sensitive in the FBP protocol (and in NoFlo-UI), use camelCase port names in NoFlo.
• Use uppercase port names in .fbp files for historical reasons, but infer case-sensitive port names from component registry when loading a graph.

[rhalff]

I experience the same issue using the fbp protocol.

If you make the lowercase decision it basically means all systems talking to the UI are forced to use/send lowercase port names.

Although it is possible to work around this by looking up port names every time one receives a payload and then restore the case sensibility, it does lead to a lot of added complexity to whatever system is trying to talk to the UI.

I think the impact of changing this seems bigger than it probably is.

A grep using toLowerCase() will probably reveal most cases:

$ grep toLowerCase ../noflo-ui/components -r  (Irrelevant lines remove)
../noflo-ui/components/noflo-noflo/src/lib/Graph.coffee:    publicPort = publicPort.toLowerCase()
../noflo-ui/components/noflo-noflo/src/lib/Graph.coffee:    publicPort = publicPort.toLowerCase()
../noflo-ui/components/noflo-noflo/src/lib/Graph.coffee:    publicPort = publicPort.toLowerCase()
../noflo-ui/components/noflo-noflo/src/lib/Graph.coffee:        graph.addInitialIndex conn.data, conn.tgt.process, conn.tgt.port.toLowerCase(), conn.tgt.index, metadata
../noflo-ui/components/noflo-noflo/src/lib/Graph.coffee:      graph.addInitial conn.data, conn.tgt.process, conn.tgt.port.toLowerCase(), metadata
../noflo-ui/components/noflo-noflo/src/lib/Graph.coffee:      graph.addEdgeIndex conn.src.process, conn.src.port.toLowerCase(), conn.src.index, conn.tgt.process, conn.tgt.port.toLowerCase(), conn.tgt.index, metadata
../noflo-ui/components/noflo-noflo/src/lib/Graph.coffee:    graph.addEdge conn.src.process, conn.src.port.toLowerCase(), conn.tgt.process, conn.tgt.port.toLowerCase(), metadata
../noflo-ui/components/noflo-noflo/src/components/Graph.coffee:    return (nodeName+'.'+portName).toLowerCase()
../noflo-ui/components/noflo-noflo/src/components/Graph.coffee:    return (nodeName+'.'+portName).toLowerCase()
../noflo-ui/components/noflo-fbp/lib/fbp.js:          result0 = (function(offset, portname) {return portname.join("").toLowerCase()})(pos0, result0[0]);
../noflo-ui/components/noflo-fbp/lib/fbp.js:          result0 = (function(offset, portname, portindex) {return { port: portname.join("").toLowerCase(), index: parseInt(portindex.join('')) }})(pos0, result0[0], result0[2]);
../noflo-ui/components/noflo-fbp/lib/fbp.js:          parser.exports.push({private:priv.toLowerCase(), public:pub.toLowerCase()})
../noflo-ui/components/noflo-fbp/lib/fbp.js:          parser.inports[pub.toLowerCase()] = {process:node, port:port.toLowerCase()}
../noflo-ui/components/noflo-fbp/lib/fbp.js:          parser.outports[pub.toLowerCase()] = {process:node, port:port.toLowerCase()}

$ grep toLowerCase elements/*
elements/noflo-context.html:            return portName.replace(/(.*)\/(.*)(_.*)\.(.*)/, '$2_$4').toLowerCase();

$ grep toLowerCase preview/ -r
preview/components/forresto-noflo-seriously/lib/SeriouslyEffect.coffee:      nofloPort = seriouslyPort.toLowerCase()

The latter seems to indicate all components should then also be checked, but it also shows how the seriouslyEffect component has to do the same conversion.

https://github.com/forresto/noflo-seriously/blob/master/lib/SeriouslyEffect.coffee#L4

[bergie]

In fd9494fece38de30ef9feb0a438df60fdcb49514 I've now added port name validation to NoFlo. Ports must match the following regexp:

/^[a-z0-9_\.]+$/

[trustmaster]

Good, this will at least avoid collisions in the FBP protocol, where most runtimes would expect port names to be case-sensitive.