cmd/shrt/internal/base/base.go in go-shrt

at v0.4.1

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// See LICENSE file for copyright and license details
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// Package base defines the foundational structures required to build
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// out the Shrt command suite.
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package base
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import (
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	"context"
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	"flag"
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)
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// Environment variable keys
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const (
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	SHRTENV           = "SHRTENV"
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	SHRT_SRVNAME      = "SHRT_SRVNAME"
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	SHRT_SCMTYPE      = "SHRT_SCMTYPE"
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	SHRT_SUFFIX       = "SHRT_SUFFIX"
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	SHRT_RDRNAME      = "SHRT_RDRNAME"
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	SHRT_BARERDR      = "SHRT_BARERDR"
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	SHRT_DBPATH       = "SHRT_DBPATH"
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	SHRT_GOSOURCEDIR  = "SHRT_GOSOURCEDIR"
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	SHRT_GOSOURCEFILE = "SHRT_GOSOURCEFILE"
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)
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// KnownEnv is a list of environment variables that affect the
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// operation of the shrt command
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const KnownEnv = `
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	SHRTENV
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	SHRT_SRVNAME
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	SHRT_SCMTYPE
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	SHRT_SUFFIX
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	SHRT_RDRNAME
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	SHRT_BARERDR
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	SHRT_DBPATH
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	SHRT_GOSOURCEDIR
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	SHRT_GOSOURCEFILE
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	`
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type Command struct {
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	Run                              func(context.Context)
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	Flags                            flag.FlagSet
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	Name, ShortHelp, LongHelp, Usage string
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	Subcommands                      []*Command
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}
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var Shrt = &Command{
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	Name: "shrt",
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	LongHelp: `Shrt is a URL shortener and go-get redirector.
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Shrt is a URL shortener service (much like bit.ly without the
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trackers) that also handles go-get requests. The latter are a
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specific GET request query used by the Go programming language
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toolchain to aid in the downloading of utilities and libraries
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prior to build and installation.
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Upon invocation, shrt does one of two things depending
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on the presence or absence of the init argument. If the init
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argument is present, a series of questions is asked, the responses
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are recorded in a configuration file, and the program exits. If
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the init argument is absent, shrt reads the configuration and
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database files into memory, binds to the port specified by the
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-l flag, and begins serving requests.
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Shortlinks are recorded in the database, and any request path
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not matching a shortlink is assumed to be a go-get request. This
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is by design, but can result in specious redirects. Additionally,
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subdirectory paths are not allowed.
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Shortlinks generate an HTTP 301 response. Go-get requests generate
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an HTTP 200 response. If configured, requests to the base path
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(i.e., "/") generate an HTTP 302 response.
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In order to add a new shortlink to the database, simply edit the
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file. After saving, users on Unix systems may send SIGHUP to a
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running server process to reload the file. Non-Unix users will need
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to restart the server.
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`,
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	Usage: "shrt <command> [arguments]",
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}
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func FindCommand(cmd string) *Command {
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	for _, sub := range Shrt.Subcommands {
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		if sub.Name == cmd {
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			return sub
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		}
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	}
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	return nil
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}
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func (c *Command) Runnable() bool {
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	return c.Run != nil
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}