Routing: path containing underscore "_" in path path variable fails to route

[BoZenKhaa]

Using a path variable with an underscore registers a path successfully, but then fails to match the path to a request. For example, consider the simple server example:

Changing the path variable from id to animal_id:

leads to the following error:

I can try to prepare a PR, but I am not sure what should actually happen. In my opinion, either

1. underscores and other allowed Julia variable names should work,
2. there should be a mention of allowed characters in the docstring,
3. register! should throw an error when trying to register a path with not allowed characters path variables,
4. trying to fetch a route with a path using the incorrect characters in path variables should show some warning

Versions:

• Julia 1.7.2
• HTTP.jl 1.0.5
• MbedTLS.jl 1.1.0

[fredrikekre]

Since they are just strings it doesn't seem necessary to limit to valid identifiers. Perhaps something like

diff --git a/src/Handlers.jl b/src/Handlers.jl
index bcb8bc8..d138d27 100644
--- a/src/Handlers.jl
+++ b/src/Handlers.jl
@@ -145,7 +145,7 @@ mutable struct Variable
     pattern::Union{Nothing, Regex}
 end

-const VARREGEX = r"^{([[:alnum:]]+):?(.*)}$"
+const VARREGEX = r"^{([^:]+)(?::(.*))}$"

 function Variable(pattern)
     re = Base.match(VARREGEX, pattern)
@@ -178,7 +178,7 @@ end
 Base.show(io::IO, x::Node) = print(io, "Node($(x.segment))")

 isvariable(x) = startswith(x, "{") && endswith(x, "}")
-segment(x) = segment == "*" ? String(segment) : isvariable(x) ? Variable(x) : String(x)
+segment(x) = isvariable(x) ? Variable(x) : String(x)

would work?

[BoZenKhaa]

Is there no reason for limiting the string to :alnum:?

[quinnj]

I think I ended up coping the :alnum: restriction from some other implementation I came across, but I agree that we don't really need to limit it at all, except maybe to ensure we can still find the closing } properly. I'd rather say curly brackets are not allowed than deal w/ some kind of escaping scheme.

@fredrikekre, mind making a PR w/ your patch?