net/httpd/conf

This package reads text written in the block style that net/httpd uses for its config, and gives back a tree. It knows nothing about web servers: it only recognises the shapes, and net/httpd decides which names are valid. You can use it for settings files of your own that look like Salam.

There are two shapes. A setting is a name, an equals sign and one or more values on the same line: max connections = 100. A block is a name, optional strings, a colon, its contents and end: location "/api/": cache = 1h end. A name may be several words (error page), values are strings in double quotes (with \n, \t, \" and \\), strings in backticks (taken as written, so a regular expression needs no doubling of backslashes), numbers with an optional unit such as 64mb or 30d, and plain words such as tls. Comments are // to the end of the line, or /* ... */.

Everything lives in a Doc, a list of nodes that point at each other by number: node 0 is the root, Find and ChildAt move down, and the fields of a node hold its words, labels, values and children. Free the document with Free when you are done with it.

The things people get wrong:

• A value list ends at the end of the line, at end, or where the next setting starts on the same line, so a = 1 b = 2 is two settings. A bare word at the end of a list is read as a value, which is why listen = 443 tls works.
• A parse stops at the first error, and ok is then false. The error has the line and the column, and ErrorText puts them in front of the message the way compilers do.
• Addresses and anything with a colon in it need quotes: listen = "127.0.0.1:8080". Without them the colon would read as the start of a block.
• A node's words hold its name, so Name joins them with single spaces. Block labels, such as the path of a location, are in labels, not in the name.

Types

struct Value

import net.httpd.conf

func main:
    text := `
server:
    site:
        listen = 80 tls
        names = "a.test www.a.test"
        location "/api/": cache = 1h end
    end
end
`
    d := conf.Parse(text)
    println d.ok, d.nodes.len(), conf.Count(d, conf.Root())
    server := conf.Find(d, conf.Root(), "server")
    site := conf.Find(d, server, "site")
    println conf.Name(d, site), conf.Count(d, site), d.nodes.get(site).block
    listen := conf.Find(d, site, "listen")
    v := d.nodes.get(listen).values.get(0)
    println v.text, v.kind == conf.VAL_NUM, v.line, v.col
    w := d.nodes.get(listen).values.get(1)
    println w.text, w.kind == conf.VAL_WORD, conf.ValueText(d, conf.Find(d, site, "names"), 0)
    names := d.nodes.get(conf.Find(d, site, "names")).values.get(0)
    println names.kind == conf.VAL_STR
    loc := conf.ChildAt(d, site, 2)
    n := d.nodes.get(loc)
    println conf.Name(d, loc), n.labels.get(0), n.block, n.words.len(), n.children.len(), n.line, n.col
    conf.Free(d)
end

struct Node

struct Doc

Constants and variables

const VAL_WORD: i32 = 0

const VAL_STR: i32 = 1

const VAL_NUM: i32 = 2

Functions

func Parse(text: str): Doc

func Free(d &: Doc)

func ErrorText(d: Doc, file: str): str

import net.httpd.conf

func show(text: str):
    d := conf.Parse(text)
    println d.ok, conf.ErrorText(d, "web.salam"), d.error, d.line, d.col
    conf.Free(d)
end

func main:
    show("server:\n    site:\n")
    show("server:\nend\nend\n")
    show("listen = \n")
    show("names = \"open\n")
    show("listen 80\n")
    show("a = 1 # no\n")
    show("ok = 1\n")
end

func Name(d: Doc, node: int): str

func Root(): int

func Count(d: Doc, node: int): int

func ChildAt(d: Doc, node: int, i: int): int

func Find(d: Doc, node: int, name: str): int

func ValueText(d: Doc, node: int, i: int): str