pacparser

README

go-pacparser

This package provides Go bindings for the pacparser library. It uses channels and a single handler to provide thread safety.

Installing

With a proper Go development environment simply run:

go get github.com/leprechau/go-pacparser

Examples

You can find a short example script in the example folder in this repository.

Documentation

Overview

Package pacparser provides Go bindings and thread safety for the pacparser library.

Notes

Package functions are called off of a pacparser instance that is instantiated with the PAC data that should be used with all other calls from the instance.

pp := pacparser.New(pacFileString)

Errors that occur are stored in the instance and should be checked after calling any function that may produce an error. Additional function calls can and in many cases will replace the instance error contents. It is up to the user to store and process instance errors as collected.

lastError := pp.LastError()

For more information please see the usage example code below.

package main

import (
	"io/ioutil"
	"log"

	"github.com/leprechau/go-pacparser"
)

func main() {
	// read in an example file
	data, err := ioutil.ReadFile("../test/good1.pac")

	// check error
	if err != nil {
		panic(err)
	}

	// create a pacparser instance
	pp := pacparser.New(string(data))

	// parse pacfile and check error
	if !pp.Parse() {
		log.Fatalf("Error parsing pacfile: %s\n", pp.LastError())
	}

	// find proxy for given url
	ok, proxy := pp.FindProxy("http://www.google.com")

	// check return
	if ok && pp.LastError() == nil {
		log.Printf("%s", proxy)
	} else {
		log.Fatalf(pp.LastError().Error())
	}
}

Index

• Constants
• type ParserInstance
  • func New(pac string) *ParserInstance
  • func (inst *ParserInstance) FindProxy(urlString string) (bool, string)
  • func (inst *ParserInstance) IsValid() bool
  • func (inst *ParserInstance) LastError() error
  • func (inst *ParserInstance) MyIp() string
  • func (inst *ParserInstance) Parse() bool
  • func (inst *ParserInstance) Reset()
  • func (inst *ParserInstance) SetMyIp(ipString string) error

Constants

const MaxConcurrency = 100

MaxConcurrency maximum pending requests

const TestURL = "http://www.google.com/"

TestURL used by IsValid()

Types

type ParserInstance

type ParserInstance struct {
	// contains filtered or unexported fields
}

ParserInstance is the core package instance that stores information for all functions contained within the package

func New

func New(pac string) *ParserInstance

New creates a new pacparser instance associated with the passed PAC file contents

func (*ParserInstance) FindProxy

func (inst *ParserInstance) FindProxy(urlString string) (bool, string)

FindProxy executes the FindProxyForURL function in the associated PAC body and find the proxy return for the given URL string. The host portion will be parsed out of the URL passed to the function. The returned string may be "" or "undefined" in addition to a proper proxy return depending on the contents of the associated PAC body.

func (*ParserInstance) IsValid

func (inst *ParserInstance) IsValid() bool

IsValid provides a shortcut that combines Parse() and FindProxy() with a test URL to quickly validate PAC syntax and basic functionality.

func (*ParserInstance) LastError

func (inst *ParserInstance) LastError() error

LastError returns the most recent error that occurred in the instance.

func (*ParserInstance) MyIp

func (inst *ParserInstance) MyIp() string

MyIp returns the IP address used by the instance.

func (*ParserInstance) Parse

func (inst *ParserInstance) Parse() bool

Parse the PAC body associated with the instance and return true or false. Errors that may occur are stored in the instance and may be retrieved by a call to LastError() and should be handled by the client BEFORE calling any additional instance functions that may overwrite the instance error state.

func (*ParserInstance) Reset

func (inst *ParserInstance) Reset()

Reset the instance IP address and error state to the default values.

func (*ParserInstance) SetMyIp

func (inst *ParserInstance) SetMyIp(ipString string) error

SetMyIp sets the IP address returned by the myIpAddress() javascript function when processing PAC scripts. The package attempts to resolve the local system hostname and defaults to "127.0.0.1" if the local hostname is not resolvable.