First public commit

3 files changed, 1295 insertions, 0 deletions

diff --git a/vendor/github.com/namsral/flag/LICENSE b/vendor/github.com/namsral/flag/LICENSE
new file mode 100644
index 0000000..0f2498b
--- /dev/null
+++ b/vendor/github.com/namsral/flag/LICENSE
@@ -0,0 +1,27 @@
+Copyright (c) 2012 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
\ No newline at end of file
diff --git a/vendor/github.com/namsral/flag/README.md b/vendor/github.com/namsral/flag/README.md
new file mode 100644
index 0000000..fba5546
--- /dev/null
+++ b/vendor/github.com/namsral/flag/README.md
@@ -0,0 +1,200 @@
+Flag
+===
+
+Flag is a drop in replacement for Go's flag package with the addition to parse files and environment variables. If you support the [twelve-factor app methodology][], Flag complies with the third factor; "Store config in the environment".
+
+[twelve-factor app methodology]: http://12factor.net
+
+An example using a gopher:
+
+```go
+$ cat > gopher.go
+    package main
+
+    import (
+        "fmt"
+    	"github.com/namsral/flag"
+	)
+    
+    var age int
+    
+    flag.IntVar(&age, "age", 0, "age of gopher")
+    flag.Parse()
+    
+    fmt.Print("age:", age)
+
+$ go run gopher.go -age 1
+age: 1
+```
+
+Same code but using an environment variable:
+
+```go
+$ export AGE=2
+$ go run gopher.go
+age: 2
+```
+    
+
+Same code but using a configuration file:
+
+```go
+$ cat > gopher.conf
+age 3
+
+$ go run gopher.go -config gopher.conf
+age: 3
+```
+
+The following table shows how flags are translated to environment variables and configuration files:
+
+| Type   | Flag          | Environment  | File         |
+| ------ | :------------ |:------------ |:------------ |
+| int    | -age 2        | AGE=2        | age 2        |
+| bool   | -female       | FEMALE=true  | female true  |
+| float  | -length 175.5 | LENGTH=175.5 | length 175.5 |
+| string | -name Gloria  | NAME=Gloria  | name Gloria  |
+
+This package is a port of Go's [flag][] package from the standard library with the addition of two functions `ParseEnv` and `ParseFile`.
+
+[flag]: http://golang.org/src/pkg/flagconfiguration
+
+
+Goals
+-----
+
+- Compatability with the original `flag` package
+- Support the [twelve-factor app methodology][]
+- Uniform user experience between the three input methods
+
+
+Why?
+---
+
+Why not use one of the many INI, JSON or YAML parsers?
+
+I find it best practice to have simple configuration options to control the behaviour of an applications when it starts up. Use basic types like ints, floats and strings for configuration options and store more complex data structures in the "datastore" layer.
+
+
+Usage
+---
+
+It's intended for projects which require a simple configuration made available through command-line flags, configuration files and shell environments. It's similar to the original `flag` package.
+
+Example:
+
+```go
+import "github.com/namsral/flag"
+
+flag.String(flag.DefaultConfigFlagname, "", "path to config file")
+flag.Int("age", 24, "help message for age")
+
+flag.Parse()
+```
+
+Order of precedence:
+
+1. Command line options
+2. Environment variables
+3. Configuration file
+4. Default values
+
+
+#### Parsing Configuration Files
+
+Create a configuration file:
+
+```go
+$ cat > ./gopher.conf
+# empty newlines and lines beginning with a "#" character are ignored.
+name bob
+
+# keys and values can also be separated by the "=" character
+age=20
+
+# booleans can be empty, set with 0, 1, true, false, etc
+hacker
+```
+
+Add a "config" flag:
+
+```go
+flag.String(flag.DefaultConfigFlagname, "", "path to config file")
+```
+
+Run the command:
+
+```go
+$ go run ./gopher.go -config ./gopher.conf
+```
+
+The default flag name for the configuration file is "config" and can be changed
+by setting `flag.DefaultConfigFlagname`:
+
+```go
+flag.DefaultConfigFlagname = "conf"
+flag.Parse()
+```
+
+#### Parsing Environment Variables
+
+Environment variables are parsed 1-on-1 with defined flags:
+
+```go
+$ export AGE=44
+$ go run ./gopher.go
+age=44
+```
+
+
+You can also parse prefixed environment variables by setting a prefix name when creating a new empty flag set:
+
+```go
+fs := flag.NewFlagSetWithEnvPrefix(os.Args[0], "GO", 0)
+fs.Int("age", 24, "help message for age")
+fs.Parse(os.Args[1:])
+...
+$ go export GO_AGE=33
+$ go run ./gopher.go
+age=33
+```
+
+
+For more examples see the [examples][] directory in the project repository.
+
+[examples]: https://github.com/namsral/flag/tree/master/examples
+
+That's it.
+
+
+License
+---
+
+
+Copyright (c) 2012 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/github.com/namsral/flag/flag.go b/vendor/github.com/namsral/flag/flag.go
new file mode 100644
index 0000000..9ee1d9c
--- /dev/null
+++ b/vendor/github.com/namsral/flag/flag.go
@@ -0,0 +1,1068 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*Package flag implements command-line flag parsing.
+okdaokddadok
+Usage:
+
+Define flags using flag.String(), Bool(), Int(), etc.
+
+This declares an integer flag, -flagname, stored in the pointer ip, with type *int.
+    import "flag"
+    var ip = flag.Int("flagname", 1234, "help message for flagname")
+If you like, you can bind the flag to a variable using the Var() functions.
+    var flagvar int
+    func init() {
+        flag.IntVar(&flagvar, "flagname", 1234, "help message for flagname")
+    }
+Or you can create custom flags that satisfy the Value interface (with
+pointer receivers) and couple them to flag parsing by
+    flag.Var(&flagVal, "name", "help message for flagname")
+For such flags, the default value is just the initial value of the variable.
+
+After all flags are defined, call
+    flag.Parse()
+to parse the command line into the defined flags.
+
+Flags may then be used directly. If you're using the flags themselves,
+they are all pointers; if you bind to variables, they're values.
+    fmt.Println("ip has value ", *ip)
+    fmt.Println("flagvar has value ", flagvar)
+
+After parsing, the arguments after the flag are available as the
+slice flag.Args() or individually as flag.Arg(i).
+The arguments are indexed from 0 through flag.NArg()-1.
+
+Command line flag syntax:
+    -flag
+    -flag=x
+    -flag x  // non-boolean flags only
+One or two minus signs may be used; they are equivalent.
+The last form is not permitted for boolean flags because the
+meaning of the command
+    cmd -x *
+will change if there is a file called 0, false, etc.  You must
+use the -flag=false form to turn off a boolean flag.
+
+Flag parsing stops just before the first non-flag argument
+("-" is a non-flag argument) or after the terminator "--".
+
+Integer flags accept 1234, 0664, 0x1234 and may be negative.
+Boolean flags may be 1, 0, t, f, true, false, TRUE, FALSE, True, False.
+Duration flags accept any input valid for time.ParseDuration.
+
+The default set of command-line flags is controlled by
+top-level functions.  The FlagSet type allows one to define
+independent sets of flags, such as to implement subcommands
+in a command-line interface. The methods of FlagSet are
+analogous to the top-level functions for the command-line
+flag set.
+*/
+package flag
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// EnvironmentPrefix defines a string that will be implicitely prefixed to a
+// flag name before looking it up in the environment variables.
+var EnvironmentPrefix = ""
+
+// DefaultConfigFlagname defines the flag name of the optional config file
+// path. Used to lookup and parse the config file when a default is set and
+// available on disk.
+var DefaultConfigFlagname = "config"
+
+// ErrHelp is the error returned if the flag -help is invoked but no such flag is defined.
+var ErrHelp = errors.New("flag: help requested")
+
+// -- bool Value
+type boolValue bool
+
+func newBoolValue(val bool, p *bool) *boolValue {
+	*p = val
+	return (*boolValue)(p)
+}
+
+func (b *boolValue) Set(s string) error {
+	v, err := strconv.ParseBool(s)
+	*b = boolValue(v)
+	return err
+}
+
+func (b *boolValue) Get() interface{} { return bool(*b) }
+
+func (b *boolValue) String() string { return fmt.Sprintf("%v", *b) }
+
+func (b *boolValue) IsBoolFlag() bool { return true }
+
+// optional interface to indicate boolean flags that can be
+// supplied without "=value" text
+type boolFlag interface {
+	Value
+	IsBoolFlag() bool
+}
+
+// -- int Value
+type intValue int
+
+func newIntValue(val int, p *int) *intValue {
+	*p = val
+	return (*intValue)(p)
+}
+
+func (i *intValue) Set(s string) error {
+	v, err := strconv.ParseInt(s, 0, 64)
+	*i = intValue(v)
+	return err
+}
+
+func (i *intValue) Get() interface{} { return int(*i) }
+
+func (i *intValue) String() string { return fmt.Sprintf("%v", *i) }
+
+// -- int64 Value
+type int64Value int64
+
+func newInt64Value(val int64, p *int64) *int64Value {
+	*p = val
+	return (*int64Value)(p)
+}
+
+func (i *int64Value) Set(s string) error {
+	v, err := strconv.ParseInt(s, 0, 64)
+	*i = int64Value(v)
+	return err
+}
+
+func (i *int64Value) Get() interface{} { return int64(*i) }
+
+func (i *int64Value) String() string { return fmt.Sprintf("%v", *i) }
+
+// -- uint Value
+type uintValue uint
+
+func newUintValue(val uint, p *uint) *uintValue {
+	*p = val
+	return (*uintValue)(p)
+}
+
+func (i *uintValue) Set(s string) error {
+	v, err := strconv.ParseUint(s, 0, 64)
+	*i = uintValue(v)
+	return err
+}
+
+func (i *uintValue) Get() interface{} { return uint(*i) }
+
+func (i *uintValue) String() string { return fmt.Sprintf("%v", *i) }
+
+// -- uint64 Value
+type uint64Value uint64
+
+func newUint64Value(val uint64, p *uint64) *uint64Value {
+	*p = val
+	return (*uint64Value)(p)
+}
+
+func (i *uint64Value) Set(s string) error {
+	v, err := strconv.ParseUint(s, 0, 64)
+	*i = uint64Value(v)
+	return err
+}
+
+func (i *uint64Value) Get() interface{} { return uint64(*i) }
+
+func (i *uint64Value) String() string { return fmt.Sprintf("%v", *i) }
+
+// -- string Value
+type stringValue string
+
+func newStringValue(val string, p *string) *stringValue {
+	*p = val
+	return (*stringValue)(p)
+}
+
+func (s *stringValue) Set(val string) error {
+	*s = stringValue(val)
+	return nil
+}
+
+func (s *stringValue) Get() interface{} { return string(*s) }
+
+func (s *stringValue) String() string { return fmt.Sprintf("%s", *s) }
+
+// -- float64 Value
+type float64Value float64
+
+func newFloat64Value(val float64, p *float64) *float64Value {
+	*p = val
+	return (*float64Value)(p)
+}
+
+func (f *float64Value) Set(s string) error {
+	v, err := strconv.ParseFloat(s, 64)
+	*f = float64Value(v)
+	return err
+}
+
+func (f *float64Value) Get() interface{} { return float64(*f) }
+
+func (f *float64Value) String() string { return fmt.Sprintf("%v", *f) }
+
+// -- time.Duration Value
+type durationValue time.Duration
+
+func newDurationValue(val time.Duration, p *time.Duration) *durationValue {
+	*p = val
+	return (*durationValue)(p)
+}
+
+func (d *durationValue) Set(s string) error {
+	v, err := time.ParseDuration(s)
+	*d = durationValue(v)
+	return err
+}
+
+func (d *durationValue) Get() interface{} { return time.Duration(*d) }
+
+func (d *durationValue) String() string { return (*time.Duration)(d).String() }
+
+// Value is the interface to the dynamic value stored in a flag.
+// (The default value is represented as a string.)
+//
+// If a Value has an IsBoolFlag() bool method returning true,
+// the command-line parser makes -name equivalent to -name=true
+// rather than using the next command-line argument.
+type Value interface {
+	String() string
+	Set(string) error
+}
+
+// Getter is an interface that allows the contents of a Value to be retrieved.
+// It wraps the Value interface, rather than being part of it, because it
+// appeared after Go 1 and its compatibility rules. All Value types provided
+// by this package satisfy the Getter interface.
+type Getter interface {
+	Value
+	Get() interface{}
+}
+
+// ErrorHandling defines how to handle flag parsing errors.
+type ErrorHandling int
+
+const (
+	ContinueOnError ErrorHandling = iota
+	ExitOnError
+	PanicOnError
+)
+
+// A FlagSet represents a set of defined flags.  The zero value of a FlagSet
+// has no name and has ContinueOnError error handling.
+type FlagSet struct {
+	// Usage is the function called when an error occurs while parsing flags.
+	// The field is a function (not a method) that may be changed to point to
+	// a custom error handler.
+	Usage func()
+
+	name          string
+	parsed        bool
+	actual        map[string]*Flag
+	formal        map[string]*Flag
+	envPrefix     string   // prefix to all env variable names
+	args          []string // arguments after flags
+	exitOnError   bool     // does the program exit if there's an error?
+	errorHandling ErrorHandling
+	output        io.Writer // nil means stderr; use out() accessor
+}
+
+// A Flag represents the state of a flag.
+type Flag struct {
+	Name     string // name as it appears on command line
+	Usage    string // help message
+	Value    Value  // value as set
+	DefValue string // default value (as text); for usage message
+}
+
+// sortFlags returns the flags as a slice in lexicographical sorted order.
+func sortFlags(flags map[string]*Flag) []*Flag {
+	list := make(sort.StringSlice, len(flags))
+	i := 0
+	for _, f := range flags {
+		list[i] = f.Name
+		i++
+	}
+	list.Sort()
+	result := make([]*Flag, len(list))
+	for i, name := range list {
+		result[i] = flags[name]
+	}
+	return result
+}
+
+func (f *FlagSet) out() io.Writer {
+	if f.output == nil {
+		return os.Stderr
+	}
+	return f.output
+}
+
+// SetOutput sets the destination for usage and error messages.
+// If output is nil, os.Stderr is used.
+func (f *FlagSet) SetOutput(output io.Writer) {
+	f.output = output
+}
+
+// VisitAll visits the flags in lexicographical order, calling fn for each.
+// It visits all flags, even those not set.
+func (f *FlagSet) VisitAll(fn func(*Flag)) {
+	for _, flag := range sortFlags(f.formal) {
+		fn(flag)
+	}
+}
+
+// VisitAll visits the command-line flags in lexicographical order, calling
+// fn for each.  It visits all flags, even those not set.
+func VisitAll(fn func(*Flag)) {
+	CommandLine.VisitAll(fn)
+}
+
+// Visit visits the flags in lexicographical order, calling fn for each.
+// It visits only those flags that have been set.
+func (f *FlagSet) Visit(fn func(*Flag)) {
+	for _, flag := range sortFlags(f.actual) {
+		fn(flag)
+	}
+}
+
+// Visit visits the command-line flags in lexicographical order, calling fn
+// for each.  It visits only those flags that have been set.
+func Visit(fn func(*Flag)) {
+	CommandLine.Visit(fn)
+}
+
+// Lookup returns the Flag structure of the named flag, returning nil if none exists.
+func (f *FlagSet) Lookup(name string) *Flag {
+	return f.formal[name]
+}
+
+// Lookup returns the Flag structure of the named command-line flag,
+// returning nil if none exists.
+func Lookup(name string) *Flag {
+	return CommandLine.formal[name]
+}
+
+// Set sets the value of the named flag.
+func (f *FlagSet) Set(name, value string) error {
+	flag, ok := f.formal[name]
+	if !ok {
+		return fmt.Errorf("no such flag -%v", name)
+	}
+	err := flag.Value.Set(value)
+	if err != nil {
+		return err
+	}
+	if f.actual == nil {
+		f.actual = make(map[string]*Flag)
+	}
+	f.actual[name] = flag
+	return nil
+}
+
+// Set sets the value of the named command-line flag.
+func Set(name, value string) error {
+	return CommandLine.Set(name, value)
+}
+
+// PrintDefaults prints, to standard error unless configured
+// otherwise, the default values of all defined flags in the set.
+func (f *FlagSet) PrintDefaults() {
+	f.VisitAll(func(flag *Flag) {
+		format := "  -%s=%s: %s\n"
+		if _, ok := flag.Value.(*stringValue); ok {
+			// put quotes on the value
+			format = "  -%s=%q: %s\n"
+		}
+		fmt.Fprintf(f.out(), format, flag.Name, flag.DefValue, flag.Usage)
+	})
+}
+
+// PrintDefaults prints to standard error the default values of all defined command-line flags.
+func PrintDefaults() {
+	CommandLine.PrintDefaults()
+}
+
+// defaultUsage is the default function to print a usage message.
+func defaultUsage(f *FlagSet) {
+	if f.name == "" {
+		fmt.Fprintf(f.out(), "Usage:\n")
+	} else {
+		fmt.Fprintf(f.out(), "Usage of %s:\n", f.name)
+	}
+	f.PrintDefaults()
+}
+
+// NOTE: Usage is not just defaultUsage(CommandLine)
+// because it serves (via godoc flag Usage) as the example
+// for how to write your own usage function.
+
+// Usage prints to standard error a usage message documenting all defined command-line flags.
+// The function is a variable that may be changed to point to a custom function.
+var Usage = func() {
+	fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])
+	PrintDefaults()
+}
+
+// NFlag returns the number of flags that have been set.
+func (f *FlagSet) NFlag() int { return len(f.actual) }
+
+// NFlag returns the number of command-line flags that have been set.
+func NFlag() int { return len(CommandLine.actual) }
+
+// Arg returns the i'th argument.  Arg(0) is the first remaining argument
+// after flags have been processed.
+func (f *FlagSet) Arg(i int) string {
+	if i < 0 || i >= len(f.args) {
+		return ""
+	}
+	return f.args[i]
+}
+
+// Arg returns the i'th command-line argument.  Arg(0) is the first remaining argument
+// after flags have been processed.
+func Arg(i int) string {
+	return CommandLine.Arg(i)
+}
+
+// NArg is the number of arguments remaining after flags have been processed.
+func (f *FlagSet) NArg() int { return len(f.args) }
+
+// NArg is the number of arguments remaining after flags have been processed.
+func NArg() int { return len(CommandLine.args) }
+
+// Args returns the non-flag arguments.
+func (f *FlagSet) Args() []string { return f.args }
+
+// Args returns the non-flag command-line arguments.
+func Args() []string { return CommandLine.args }
+
+// BoolVar defines a bool flag with specified name, default value, and usage string.
+// The argument p points to a bool variable in which to store the value of the flag.
+func (f *FlagSet) BoolVar(p *bool, name string, value bool, usage string) {
+	f.Var(newBoolValue(value, p), name, usage)
+}
+
+// BoolVar defines a bool flag with specified name, default value, and usage string.
+// The argument p points to a bool variable in which to store the value of the flag.
+func BoolVar(p *bool, name string, value bool, usage string) {
+	CommandLine.Var(newBoolValue(value, p), name, usage)
+}
+
+// Bool defines a bool flag with specified name, default value, and usage string.
+// The return value is the address of a bool variable that stores the value of the flag.
+func (f *FlagSet) Bool(name string, value bool, usage string) *bool {
+	p := new(bool)
+	f.BoolVar(p, name, value, usage)
+	return p
+}
+
+// Bool defines a bool flag with specified name, default value, and usage string.
+// The return value is the address of a bool variable that stores the value of the flag.
+func Bool(name string, value bool, usage string) *bool {
+	return CommandLine.Bool(name, value, usage)
+}
+
+// IntVar defines an int flag with specified name, default value, and usage string.
+// The argument p points to an int variable in which to store the value of the flag.
+func (f *FlagSet) IntVar(p *int, name string, value int, usage string) {
+	f.Var(newIntValue(value, p), name, usage)
+}
+
+// IntVar defines an int flag with specified name, default value, and usage string.
+// The argument p points to an int variable in which to store the value of the flag.
+func IntVar(p *int, name string, value int, usage string) {
+	CommandLine.Var(newIntValue(value, p), name, usage)
+}
+
+// Int defines an int flag with specified name, default value, and usage string.
+// The return value is the address of an int variable that stores the value of the flag.
+func (f *FlagSet) Int(name string, value int, usage string) *int {
+	p := new(int)
+	f.IntVar(p, name, value, usage)
+	return p
+}
+
+// Int defines an int flag with specified name, default value, and usage string.
+// The return value is the address of an int variable that stores the value of the flag.
+func Int(name string, value int, usage string) *int {
+	return CommandLine.Int(name, value, usage)
+}
+
+// Int64Var defines an int64 flag with specified name, default value, and usage string.
+// The argument p points to an int64 variable in which to store the value of the flag.
+func (f *FlagSet) Int64Var(p *int64, name string, value int64, usage string) {
+	f.Var(newInt64Value(value, p), name, usage)
+}
+
+// Int64Var defines an int64 flag with specified name, default value, and usage string.
+// The argument p points to an int64 variable in which to store the value of the flag.
+func Int64Var(p *int64, name string, value int64, usage string) {
+	CommandLine.Var(newInt64Value(value, p), name, usage)
+}
+
+// Int64 defines an int64 flag with specified name, default value, and usage string.
+// The return value is the address of an int64 variable that stores the value of the flag.
+func (f *FlagSet) Int64(name string, value int64, usage string) *int64 {
+	p := new(int64)
+	f.Int64Var(p, name, value, usage)
+	return p
+}
+
+// Int64 defines an int64 flag with specified name, default value, and usage string.
+// The return value is the address of an int64 variable that stores the value of the flag.
+func Int64(name string, value int64, usage string) *int64 {
+	return CommandLine.Int64(name, value, usage)
+}
+
+// UintVar defines a uint flag with specified name, default value, and usage string.
+// The argument p points to a uint variable in which to store the value of the flag.
+func (f *FlagSet) UintVar(p *uint, name string, value uint, usage string) {
+	f.Var(newUintValue(value, p), name, usage)
+}
+
+// UintVar defines a uint flag with specified name, default value, and usage string.
+// The argument p points to a uint  variable in which to store the value of the flag.
+func UintVar(p *uint, name string, value uint, usage string) {
+	CommandLine.Var(newUintValue(value, p), name, usage)
+}
+
+// Uint defines a uint flag with specified name, default value, and usage string.
+// The return value is the address of a uint  variable that stores the value of the flag.
+func (f *FlagSet) Uint(name string, value uint, usage string) *uint {
+	p := new(uint)
+	f.UintVar(p, name, value, usage)
+	return p
+}
+
+// Uint defines a uint flag with specified name, default value, and usage string.
+// The return value is the address of a uint  variable that stores the value of the flag.
+func Uint(name string, value uint, usage string) *uint {
+	return CommandLine.Uint(name, value, usage)
+}
+
+// Uint64Var defines a uint64 flag with specified name, default value, and usage string.
+// The argument p points to a uint64 variable in which to store the value of the flag.
+func (f *FlagSet) Uint64Var(p *uint64, name string, value uint64, usage string) {
+	f.Var(newUint64Value(value, p), name, usage)
+}
+
+// Uint64Var defines a uint64 flag with specified name, default value, and usage string.
+// The argument p points to a uint64 variable in which to store the value of the flag.
+func Uint64Var(p *uint64, name string, value uint64, usage string) {
+	CommandLine.Var(newUint64Value(value, p), name, usage)
+}
+
+// Uint64 defines a uint64 flag with specified name, default value, and usage string.
+// The return value is the address of a uint64 variable that stores the value of the flag.
+func (f *FlagSet) Uint64(name string, value uint64, usage string) *uint64 {
+	p := new(uint64)
+	f.Uint64Var(p, name, value, usage)
+	return p
+}
+
+// Uint64 defines a uint64 flag with specified name, default value, and usage string.
+// The return value is the address of a uint64 variable that stores the value of the flag.
+func Uint64(name string, value uint64, usage string) *uint64 {
+	return CommandLine.Uint64(name, value, usage)
+}
+
+// StringVar defines a string flag with specified name, default value, and usage string.
+// The argument p points to a string variable in which to store the value of the flag.
+func (f *FlagSet) StringVar(p *string, name string, value string, usage string) {
+	f.Var(newStringValue(value, p), name, usage)
+}
+
+// StringVar defines a string flag with specified name, default value, and usage string.
+// The argument p points to a string variable in which to store the value of the flag.
+func StringVar(p *string, name string, value string, usage string) {
+	CommandLine.Var(newStringValue(value, p), name, usage)
+}
+
+// String defines a string flag with specified name, default value, and usage string.
+// The return value is the address of a string variable that stores the value of the flag.
+func (f *FlagSet) String(name string, value string, usage string) *string {
+	p := new(string)
+	f.StringVar(p, name, value, usage)
+	return p
+}
+
+// String defines a string flag with specified name, default value, and usage string.
+// The return value is the address of a string variable that stores the value of the flag.
+func String(name string, value string, usage string) *string {
+	return CommandLine.String(name, value, usage)
+}
+
+// Float64Var defines a float64 flag with specified name, default value, and usage string.
+// The argument p points to a float64 variable in which to store the value of the flag.
+func (f *FlagSet) Float64Var(p *float64, name string, value float64, usage string) {
+	f.Var(newFloat64Value(value, p), name, usage)
+}
+
+// Float64Var defines a float64 flag with specified name, default value, and usage string.
+// The argument p points to a float64 variable in which to store the value of the flag.
+func Float64Var(p *float64, name string, value float64, usage string) {
+	CommandLine.Var(newFloat64Value(value, p), name, usage)
+}
+
+// Float64 defines a float64 flag with specified name, default value, and usage string.
+// The return value is the address of a float64 variable that stores the value of the flag.
+func (f *FlagSet) Float64(name string, value float64, usage string) *float64 {
+	p := new(float64)
+	f.Float64Var(p, name, value, usage)
+	return p
+}
+
+// Float64 defines a float64 flag with specified name, default value, and usage string.
+// The return value is the address of a float64 variable that stores the value of the flag.
+func Float64(name string, value float64, usage string) *float64 {
+	return CommandLine.Float64(name, value, usage)
+}
+
+// DurationVar defines a time.Duration flag with specified name, default value, and usage string.
+// The argument p points to a time.Duration variable in which to store the value of the flag.
+func (f *FlagSet) DurationVar(p *time.Duration, name string, value time.Duration, usage string) {
+	f.Var(newDurationValue(value, p), name, usage)
+}
+
+// DurationVar defines a time.Duration flag with specified name, default value, and usage string.
+// The argument p points to a time.Duration variable in which to store the value of the flag.
+func DurationVar(p *time.Duration, name string, value time.Duration, usage string) {
+	CommandLine.Var(newDurationValue(value, p), name, usage)
+}
+
+// Duration defines a time.Duration flag with specified name, default value, and usage string.
+// The return value is the address of a time.Duration variable that stores the value of the flag.
+func (f *FlagSet) Duration(name string, value time.Duration, usage string) *time.Duration {
+	p := new(time.Duration)
+	f.DurationVar(p, name, value, usage)
+	return p
+}
+
+// Duration defines a time.Duration flag with specified name, default value, and usage string.
+// The return value is the address of a time.Duration variable that stores the value of the flag.
+func Duration(name string, value time.Duration, usage string) *time.Duration {
+	return CommandLine.Duration(name, value, usage)
+}
+
+// Var defines a flag with the specified name and usage string. The type and
+// value of the flag are represented by the first argument, of type Value, which
+// typically holds a user-defined implementation of Value. For instance, the
+// caller could create a flag that turns a comma-separated string into a slice
+// of strings by giving the slice the methods of Value; in particular, Set would
+// decompose the comma-separated string into the slice.
+func (f *FlagSet) Var(value Value, name string, usage string) {
+	// Remember the default value as a string; it won't change.
+	flag := &Flag{name, usage, value, value.String()}
+	_, alreadythere := f.formal[name]
+	if alreadythere {
+		var msg string
+		if f.name == "" {
+			msg = fmt.Sprintf("flag redefined: %s", name)
+		} else {
+			msg = fmt.Sprintf("%s flag redefined: %s", f.name, name)
+		}
+		fmt.Fprintln(f.out(), msg)
+		panic(msg) // Happens only if flags are declared with identical names
+	}
+	if f.formal == nil {
+		f.formal = make(map[string]*Flag)
+	}
+	f.formal[name] = flag
+}
+
+// Var defines a flag with the specified name and usage string. The type and
+// value of the flag are represented by the first argument, of type Value, which
+// typically holds a user-defined implementation of Value. For instance, the
+// caller could create a flag that turns a comma-separated string into a slice
+// of strings by giving the slice the methods of Value; in particular, Set would
+// decompose the comma-separated string into the slice.
+func Var(value Value, name string, usage string) {
+	CommandLine.Var(value, name, usage)
+}
+
+// failf prints to standard error a formatted error and usage message and
+// returns the error.
+func (f *FlagSet) failf(format string, a ...interface{}) error {
+	err := fmt.Errorf(format, a...)
+	fmt.Fprintln(f.out(), err)
+	f.usage()
+	return err
+}
+
+// usage calls the Usage method for the flag set, or the usage function if
+// the flag set is CommandLine.
+func (f *FlagSet) usage() {
+	if f == CommandLine {
+		Usage()
+	} else if f.Usage == nil {
+		defaultUsage(f)
+	} else {
+		f.Usage()
+	}
+}
+
+// parseOne parses one flag. It reports whether a flag was seen.
+func (f *FlagSet) parseOne() (bool, error) {
+	if len(f.args) == 0 {
+		return false, nil
+	}
+	s := f.args[0]
+	if len(s) == 0 || s[0] != '-' || len(s) == 1 {
+		return false, nil
+	}
+	numMinuses := 1
+	if s[1] == '-' {
+		numMinuses++
+		if len(s) == 2 { // "--" terminates the flags
+			f.args = f.args[1:]
+			return false, nil
+		}
+	}
+	name := s[numMinuses:]
+	if len(name) == 0 || name[0] == '-' || name[0] == '=' {
+		return false, f.failf("bad flag syntax: %s", s)
+	}
+
+	// ignore go test flags
+	if strings.HasPrefix(name, "test.") {
+		return false, nil
+	}
+
+	// it's a flag. does it have an argument?
+	f.args = f.args[1:]
+	hasValue := false
+	value := ""
+	for i := 1; i < len(name); i++ { // equals cannot be first
+		if name[i] == '=' {
+			value = name[i+1:]
+			hasValue = true
+			name = name[0:i]
+			break
+		}
+	}
+	m := f.formal
+	flag, alreadythere := m[name] // BUG
+	if !alreadythere {
+		if name == "help" || name == "h" { // special case for nice help message.
+			f.usage()
+			return false, ErrHelp
+		}
+		return false, f.failf("flag provided but not defined: -%s", name)
+	}
+	if fv, ok := flag.Value.(boolFlag); ok && fv.IsBoolFlag() { // special case: doesn't need an arg
+		if hasValue {
+			if err := fv.Set(value); err != nil {
+				return false, f.failf("invalid boolean value %q for  -%s: %v", value, name, err)
+			}
+		} else {
+			fv.Set("true")
+		}
+	} else {
+		// It must have a value, which might be the next argument.
+		if !hasValue && len(f.args) > 0 {
+			// value is the next arg
+			hasValue = true
+			value, f.args = f.args[0], f.args[1:]
+		}
+		if !hasValue {
+			return false, f.failf("flag needs an argument: -%s", name)
+		}
+		if err := flag.Value.Set(value); err != nil {
+			return false, f.failf("invalid value %q for flag -%s: %v", value, name, err)
+		}
+	}
+	if f.actual == nil {
+		f.actual = make(map[string]*Flag)
+	}
+	f.actual[name] = flag
+	return true, nil
+}
+
+// Parse parses flag definitions from the argument list, which should not
+// include the command name.  Must be called after all flags in the FlagSet
+// are defined and before flags are accessed by the program.
+// The return value will be ErrHelp if -help was set but not defined.
+func (f *FlagSet) Parse(arguments []string) error {
+	f.parsed = true
+	f.args = arguments
+	for {
+		seen, err := f.parseOne()
+		if seen {
+			continue
+		}
+		if err == nil {
+			break
+		}
+		switch f.errorHandling {
+		case ContinueOnError:
+			return err
+		case ExitOnError:
+			os.Exit(2)
+		case PanicOnError:
+			panic(err)
+		}
+	}
+
+	// Parse environment variables
+	if err := f.ParseEnv(os.Environ()); err != nil {
+		switch f.errorHandling {
+		case ContinueOnError:
+			return err
+		case ExitOnError:
+			os.Exit(2)
+		case PanicOnError:
+			panic(err)
+		}
+		return err
+	}
+
+	// Parse configuration from file
+	var cFile string
+	if cf := f.formal[DefaultConfigFlagname]; cf != nil {
+		cFile = cf.Value.String()
+	}
+	if cf := f.actual[DefaultConfigFlagname]; cf != nil {
+		cFile = cf.Value.String()
+	}
+	if cFile != "" {
+		if err := f.ParseFile(cFile); err != nil {
+			switch f.errorHandling {
+			case ContinueOnError:
+				return err
+			case ExitOnError:
+				os.Exit(2)
+			case PanicOnError:
+				panic(err)
+			}
+			return err
+		}
+	}
+
+	return nil
+}
+
+// ParseEnv parses flags from environment variables.
+// Flags already set will be ignored.
+func (f *FlagSet) ParseEnv(environ []string) error {
+
+	m := f.formal
+
+	env := make(map[string]string)
+	for _, s := range environ {
+		i := strings.Index(s, "=")
+		if i < 1 {
+			continue
+		}
+		env[s[0:i]] = s[i+1 : len(s)]
+	}
+
+	for _, flag := range m {
+		name := flag.Name
+		_, set := f.actual[name]
+		if set {
+			continue
+		}
+
+		flag, alreadythere := m[name]
+		if !alreadythere {
+			if name == "help" || name == "h" { // special case for nice help message.
+				f.usage()
+				return ErrHelp
+			}
+			return f.failf("environment variable provided but not defined: %s", name)
+		}
+
+		envKey := strings.ToUpper(flag.Name)
+		if f.envPrefix != "" {
+			envKey = f.envPrefix + "_" + envKey
+		}
+		envKey = strings.Replace(envKey, "-", "_", -1)
+
+		value, isSet := env[envKey]
+		if !isSet {
+			continue
+		}
+
+		hasValue := false
+		if len(value) > 0 {
+			hasValue = true
+		}
+
+		if fv, ok := flag.Value.(boolFlag); ok && fv.IsBoolFlag() { // special case: doesn't need an arg
+			if hasValue {
+				if err := fv.Set(value); err != nil {
+					return f.failf("invalid boolean value %q for environment variable %s: %v", value, name, err)
+				}
+			} else {
+				// flag without value is regarded a bool
+				fv.Set("true")
+			}
+		} else {
+			if err := flag.Value.Set(value); err != nil {
+				return f.failf("invalid value %q for environment variable %s: %v", value, name, err)
+			}
+		}
+
+		// update f.actual
+		if f.actual == nil {
+			f.actual = make(map[string]*Flag)
+		}
+		f.actual[name] = flag
+
+	}
+	return nil
+}
+
+// ParseFile parses flags from the file in path.
+// Same format as commandline argumens, newlines and lines beginning with a
+// "#" charater are ignored. Flags already set will be ignored.
+func (f *FlagSet) ParseFile(path string) error {
+
+	// Extract arguments from file
+	fp, err := os.Open(path)
+	if err != nil {
+		return err
+	}
+	defer fp.Close()
+
+	scanner := bufio.NewScanner(fp)
+	for scanner.Scan() {
+		line := scanner.Text()
+
+		// Ignore empty lines
+		if len(line) == 0 {
+			continue
+		}
+
+		// Ignore comments
+		if line[:1] == "#" {
+			continue
+		}
+
+		// Match `key=value` and `key value`
+		var name, value string
+		hasValue := false
+		for i, v := range line {
+			if v == '=' || v == ' ' {
+				hasValue = true
+				name, value = line[:i], line[i+1:]
+				break
+			}
+		}
+
+		if hasValue == false {
+			name = line
+		}
+
+		// Ignore flag when already set; arguments have precedence over file
+		if f.actual[name] != nil {
+			continue
+		}
+
+		m := f.formal
+		flag, alreadythere := m[name]
+		if !alreadythere {
+			if name == "help" || name == "h" { // special case for nice help message.
+				f.usage()
+				return ErrHelp
+			}
+			return f.failf("configuration variable provided but not defined: %s", name)
+		}
+
+		if fv, ok := flag.Value.(boolFlag); ok && fv.IsBoolFlag() { // special case: doesn't need an arg
+			if hasValue {
+				if err := fv.Set(value); err != nil {
+					return f.failf("invalid boolean value %q for configuration variable %s: %v", value, name, err)
+				}
+			} else {
+				// flag without value is regarded a bool
+				fv.Set("true")
+			}
+		} else {
+			if err := flag.Value.Set(value); err != nil {
+				return f.failf("invalid value %q for configuration variable %s: %v", value, name, err)
+			}
+		}
+
+		// update f.actual
+		if f.actual == nil {
+			f.actual = make(map[string]*Flag)
+		}
+		f.actual[name] = flag
+	}
+
+	if err := scanner.Err(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Parsed reports whether f.Parse has been called.
+func (f *FlagSet) Parsed() bool {
+	return f.parsed
+}
+
+// Parse parses the command-line flags from os.Args[1:].  Must be called
+// after all flags are defined and before flags are accessed by the program.
+func Parse() {
+	// Ignore errors; CommandLine is set for ExitOnError.
+	CommandLine.Parse(os.Args[1:])
+}
+
+// Parsed returns true if the command-line flags have been parsed.
+func Parsed() bool {
+	return CommandLine.Parsed()
+}
+
+// CommandLine is the default set of command-line flags, parsed from os.Args.
+// The top-level functions such as BoolVar, Arg, and on are wrappers for the
+// methods of CommandLine.
+var CommandLine = NewFlagSet(os.Args[0], ExitOnError)
+
+// NewFlagSet returns a new, empty flag set with the specified name and
+// error handling property.
+func NewFlagSet(name string, errorHandling ErrorHandling) *FlagSet {
+	f := &FlagSet{
+		name:          name,
+		errorHandling: errorHandling,
+	}
+	return f
+}
+
+// NewFlagSetWithEnvPrefix returns a new empty flag set with the specified name,
+// environment variable prefix, and error handling property.
+func NewFlagSetWithEnvPrefix(name string, prefix string, errorHandling ErrorHandling) *FlagSet {
+	f := NewFlagSet(name, errorHandling)
+	f.envPrefix = prefix
+	return f
+}
+
+// Init sets the name, environment name prefix, and error handling property
+// for a flag set.
+// By default, the zero FlagSet uses an empty name, EnvironmentPrefix, and the
+// ContinueOnError error handling policy.
+func (f *FlagSet) Init(name string, errorHandling ErrorHandling) {
+	f.name = name
+	f.envPrefix = EnvironmentPrefix
+	f.errorHandling = errorHandling
+}