utils

Documentation

Overview

Package utils provides various utility functions for the application.

Index

• Constants
• Variables
• func Do(fn []func() error) error
• func FindDuplicates(hashes []*Phash, distance int, durationDiff float64) [][]int
• func GenerateETag(data []byte) string
• func GetBase64StringFromData(data []byte) string
• func GetDataFromBase64String(encodedString string) ([]byte, error)
• func GetVTTTime(fracSeconds float64) string
• func IsTrue(b *bool) bool
• func MergeMaps(dest map[string]interface{}, src map[string]interface{})
• func NotNilFields(subject interface{}, tag string) []string
• func ParseDateStringAsTime(dateString string) (time.Time, error)
• func PhashToString(phash int64) string
• func ProcessBase64Image(imageString string) ([]byte, error)
• func ProcessImageInput(ctx context.Context, imageInput string) ([]byte, error)
• func ReadImageFromURL(ctx context.Context, url string) ([]byte, error)
• func ServeImage(w http.ResponseWriter, r *http.Request, image []byte)
• func ServeStaticContent(w http.ResponseWriter, r *http.Request, data []byte)
• func ServeStaticFile(w http.ResponseWriter, r *http.Request, filepath string)
• func ServeStaticFileModTime(w http.ResponseWriter, r *http.Request, path string, modTime time.Time)
• func StrFormat(format string, m StrFormatMap) string
• func StringToPhash(s string) (int64, error)
• func StringerSliceToStringSlice[V fmt.Stringer](v []V) []string
• func Timeout(todo func(), waitTime time.Duration, onTimeout func(done chan struct{}))
• func URLFromHandle(input string, siteURL string) string
• type MutexManager
  • func NewMutexManager() *MutexManager
  • func (csm *MutexManager) Claim(mutexType string, key string, done <-chan struct{})
• type NestedMap
  • func (m NestedMap) Delete(key string)
  • func (m NestedMap) Get(key string) (interface{}, bool)
  • func (m NestedMap) Set(key string, value interface{})
• type Phash
• type StrFormatMap
• type URLMap
  • func (m URLMap) GetFilesystemLocation(url string) (newURL string, fsPath string)
• type ValueOnlyContext
  • func (ValueOnlyContext) Deadline() (deadline time.Time, ok bool)
  • func (ValueOnlyContext) Done() <-chan struct{}
  • func (ValueOnlyContext) Err() error

Examples

• StrFormat

Constants

const FirefoxLinux = "Mozilla/5.0 (X11; Linux x86_64; rv:88.0) Gecko/20100101 Firefox/88.0"

const FirefoxLinuxArm = "Mozilla/5.0 (X11; Linux armv7l; rv:86.0) Gecko/20100101 Firefox/86.0"

const FirefoxLinuxArm64 = "Mozilla/5.0 (X11; Linux aarch64; rv:86.0) Gecko/20100101 Firefox/86.0"

const FirefoxWindows = "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:88.0) Gecko/20100101 Firefox/88.0"

const Safari = "" /* 131-byte string literal not displayed */

valid UA from https://user-agents.net

Variables

var PendingGenerateResource, _ = GetDataFromBase64String("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")

Functions

func Do

func Do(fn []func() error) error

Do executes each function in the slice in order. If any function returns an error, it is returned immediately.

func FindDuplicates

func FindDuplicates(hashes []*Phash, distance int, durationDiff float64) [][]int

func GenerateETag

func GenerateETag(data []byte) string

Returns an MD5 hash of data, formatted for use as an HTTP ETag header. Intended for use with `http.ServeContent`, to respond to conditional requests.

func GetBase64StringFromData

func GetBase64StringFromData(data []byte) string

GetBase64StringFromData returns the given byte slice as a base64 encoded string

func GetDataFromBase64String

func GetDataFromBase64String(encodedString string) ([]byte, error)

GetDataFromBase64String returns the given base64 encoded string as a byte slice

func GetVTTTime

func GetVTTTime(fracSeconds float64) string

GetVTTTime returns a timestamp appropriate for VTT files (hh:mm:ss.mmm)

func IsTrue

func IsTrue(b *bool) bool

IsTrue returns true if the bool pointer is not nil and true.

func MergeMaps

func MergeMaps(dest map[string]interface{}, src map[string]interface{})

MergeMaps merges src into dest. If a key exists in both maps, the value from src is used.

func NotNilFields

func NotNilFields(subject interface{}, tag string) []string

NotNilFields returns the matching tag values of fields from an object that are not nil. Panics if the provided object is not a struct.

func ParseDateStringAsTime

func ParseDateStringAsTime(dateString string) (time.Time, error)

func PhashToString

func PhashToString(phash int64) string

func ProcessBase64Image

func ProcessBase64Image(imageString string) ([]byte, error)

ProcessBase64Image transforms a base64 encoded string from a form post and returns the image itself as a byte slice.

func ProcessImageInput

func ProcessImageInput(ctx context.Context, imageInput string) ([]byte, error)

ProcessImageInput transforms an image string either from a base64 encoded string, or from a URL, and returns the image as a byte slice

func ReadImageFromURL

func ReadImageFromURL(ctx context.Context, url string) ([]byte, error)

ReadImageFromURL returns image data from a URL

func ServeImage

func ServeImage(w http.ResponseWriter, r *http.Request, image []byte)

func ServeStaticContent

func ServeStaticContent(w http.ResponseWriter, r *http.Request, data []byte)

Serves static content, adding Cache-Control: no-cache and a generated ETag header. Responds to conditional requests using the ETag.

func ServeStaticFile

func ServeStaticFile(w http.ResponseWriter, r *http.Request, filepath string)

Serves static content at filepath, adding Cache-Control: no-cache. Responds to conditional requests using the file modtime.

func ServeStaticFileModTime

func ServeStaticFileModTime(w http.ResponseWriter, r *http.Request, path string, modTime time.Time)

ServeStaticFileModTime serves a static file at the given path using the given modTime instead of the file modTime.

func StrFormat

func StrFormat(format string, m StrFormatMap) string

StrFormat formats the provided format string, replacing placeholders in the form of "{fieldName}" with the values in the provided StrFormatMap.

For example,

StrFormat("{foo} bar {baz}", StrFormatMap{
    "foo": "bar",
    "baz": "abc",
})

would return: "bar bar abc"

Example

fmt.Println(StrFormat("{foo} bar {baz}", StrFormatMap{
	"foo": "bar",
	"baz": "abc",
}))

Output:

bar bar abc

func StringToPhash

func StringToPhash(s string) (int64, error)

func StringerSliceToStringSlice

func StringerSliceToStringSlice[V fmt.Stringer](v []V) []string

StringerSliceToStringSlice converts a slice of fmt.Stringers to a slice of strings.

func Timeout

func Timeout(todo func(), waitTime time.Duration, onTimeout func(done chan struct{}))

Timeout executes the provided todo function, and waits for it to return. If the function does not return before the waitTime duration is elapsed, then onTimeout is executed, passing a channel that will be closed when the function returns.

func URLFromHandle

func URLFromHandle(input string, siteURL string) string

URLFromHandle adds the site URL to the input if the input is not already a URL siteURL must not end with a slash

Types

type MutexManager

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

MutexManager manages access to mutexes using a mutex type and key.

func NewMutexManager

func NewMutexManager() *MutexManager

NewMutexManager returns a new instance of MutexManager.

func (*MutexManager) Claim

func (csm *MutexManager) Claim(mutexType string, key string, done <-chan struct{})

Claim blocks until the mutex for the mutexType and key pair is available. The mutex is then claimed by the calling code until the provided done channel is closed.

type NestedMap

type NestedMap map[string]interface{}

NestedMap is a map that supports nested keys. It is expected that the nested maps are of type map[string]interface{}

func (NestedMap) Delete

func (m NestedMap) Delete(key string)

func (NestedMap) Get

func (m NestedMap) Get(key string) (interface{}, bool)

func (NestedMap) Set

func (m NestedMap) Set(key string, value interface{})

type Phash

type Phash struct {
	SceneID   int     `db:"id"`
	Hash      int64   `db:"phash"`
	Duration  float64 `db:"duration"`
	Neighbors []int
	Bucket    int
}

type StrFormatMap

type StrFormatMap map[string]interface{}

type URLMap

type URLMap map[string]string

URLMap is a map of URL prefixes to filesystem locations

func (URLMap) GetFilesystemLocation

func (m URLMap) GetFilesystemLocation(url string) (newURL string, fsPath string)

GetFilesystemLocation returns the adjusted URL and the filesystem location

type ValueOnlyContext

type ValueOnlyContext struct {
	context.Context
}

func (ValueOnlyContext) Deadline

func (ValueOnlyContext) Deadline() (deadline time.Time, ok bool)

func (ValueOnlyContext) Done

func (ValueOnlyContext) Done() <-chan struct{}

func (ValueOnlyContext) Err

func (ValueOnlyContext) Err() error