Installation: julia> Pkg.add("HttpCommon")

This package provides types and helper functions for dealing with the HTTP protocol in Julia:

• types to represent Requests, Responses, and Headers
• a dictionary of STATUS_CODES (maps integer codes to string descriptions; covers all the codes from the RFCs)
• a bitmask representation of HTTP request methods
• a function to escapeHTML in a String
• a pair of functions to encodeURI and decodeURI
• a function to turn a query string from a url into a Dict{String,String}

A Request represents an HTTP request sent by a client to a server.

:::julia
type Request
    method::String
    resource::String
    headers::Headers
    data::String
end

• method is an HTTP methods string ("GET", "PUT", etc)
• resource is the url resource requested ("/hello/world")
• headers is a Dict of field name Strings to value Strings
• data is the data in the request

A Response represents an HTTP response sent to a client by a server.

:::julia
type Response
    status::Int
    headers::Headers
    data::HttpData
    finished::Bool
end

• status is the HTTP status code (see STATUS_CODES) [default: 200]
• headers is the Dict of headers [default: headers(), see Headers below]
• data is the response data (as a String or Array{Uint8}) [default: ""]
• finished is true if the Reponse is valid, meaning that it can be converted to an actual HTTP response [default: false]

There are a variety of constructors for Response, which set sane defaults for unspecified values.

:::julia
Response([statuscode::Int])
Response(statuscode::Int,[h::Headers],[d::HttpData])
Response(d::HttpData,[h::Headers])

Headers is a type alias for Dict{String,String}. There is a default constructor, headers, to produce a reasonable default set of headers. The defaults are as follows:

:::julia
[ "Server" => "Julia/$VERSION",
  "Content-Type" => "text/html; charset=utf-8",
  "Content-Language" => "en",
  "Date" => RFC1123_datetime()]

The last setting, "Date" uses another HttpCommon function:

:::julia
RFC1123_datetime([CalendarTime])

When an argument is not provided, the current time (now()) is used. RFC1123 describes the correct format for putting timestamps into HTTP headers.

STATUS_CODES is a const Dict{Int,String}. It maps all the status codes defined in RFC's to their descriptions.

:::julia
STATUS_CODES[200] #=> "OK"
STATUS_CODES[404] #=> "Not Found"
STATUS_CODES[418] #=> "I'm a teapot"
STATUS_CODES[500] #=> "Internal Server Error"

HttpCommon provides Int bitmasks to represent the HTTP request methods (GET, POST, PUT, UPDATE, DELETE, OPTIONS, HEAD). There are two dictionaries, HttpMethodNameToBitmask and HttpMethodBitmaskToName, to allow for mapping back and forth from String names to Int bitmasks.

The purpose of having bitmasks is that you can write GET | POST | UPDATE and end up with a bitmask representing the union of those HTTP methods.

escapeHTML will return a new String with the following characters escaped: &, <, >, ".

encodeURI returns a new, URI-safe string. It escapes all non-URI characters (only letters, digits, -, _ , ., and ~ are allowed) in the standard way.

decodeURI returns a new String with all the unsafe characters returned to their original meanings. It works with the output of encodeURI as well as other standard URI encoders.

parsequerystring takes a query string (as from a URL) and returns a Dict{String,String} representing the same data.

An example:

:::julia
 q = "foo=bar&baz=%3Ca%20href%3D%27http%3A%2F%2Fwww.hackershool.com%27%3Ehello%20world%21%3C%2Fa%3E"
parsequerystring(q)
# => ["foo"=>"bar","baz"=>"<a href='https://www.hackershool.com'>hello world!</a>"]

:::::::::::::
::         ::
:: Made at ::
::         ::
:::::::::::::
     ::
Hacker School
:::::::::::::