AndreKR

Elasticsearch notes

Things named "explain"

Three things can be explained in elasticsearch:

Explain for each hit how its score was computed (Docs: Explain)

GET //_search?explain

AndreKR

@echo off

set PLINK_PATH=C:\Program Files (x86)\PuTTY\plink.exe
set WIRESHARK_PATH=C:\Program Files\Wireshark\Wireshark.exe

if "%1" == "" goto :usage

"%PLINK_PATH%" -ssh %1 "tcpdump -ni %2 -s 0 -w - not port 22" | "%WIRESHARK_PATH%" -k -i -
goto :end

AndreKR

DROP TABLE IF EXISTS public.with_enum;
DROP TABLE IF EXISTS public.with_text;
DROP TYPE IF EXISTS my_enum;

CREATE TYPE public.my_enum AS ENUM ('axyzxyz', 'bxyzxyz', 'cxyzxyz', 'dxyzxyz');

CREATE TABLE public.with_enum (
  id serial NOT NULL PRIMARY KEY,
  blah integer,
  thecolumn my_enum

AndreKR

func handleRequest(w http.ResponseWriter, r *http.Request) {

	cn := w.(http.CloseNotifier)
	cc := cn.CloseNotify()

	go func() {
		<-cc
		log.Println("Closed!")
	}()

AndreKR

// (I prefer "Two channels wrapped" and "Anonymous struct" over the other two)

// Two channels
resultCh := make(chan Result)
errorCh := make(chan Result)

go func(resultCh chan Result, errorCh chan errpr) {
  errorCh <- errors.New("Does not compute")}
  resultCh <- result
}(resultCh, errorCh)

AndreKR

package main

// Trigger ensures a worker runs once after it has been triggered, no matter how many trigger events happened during
// its last run.
//
// Usage:
//   trigger := NewTrigger()
//   go func() {
//     for _ = range trigger {
//       do_work()

AndreKR

// While the Go documentation promotes the context package for keeping track of request context and cancelation, to
// actually use it for canceling work in http requests some plumbing is necessary:

// getCancelableContextFromResponseWriter gets a context.Context that is canceled when the client (browser) closes the connection
func getCancelableContextFromResponseWriter(w http.ResponseWriter) context.Context {

	// Create a context that can be handed down to the workers to relay cancellation
	ctx, cancelContext := context.WithCancel(context.Background())

	// Get a channel that receives a value when the request is canceled

AndreKR

var exeDir = getExeDir()

func getExeDir() string {
	if os.Getenv("EXEDIR") != "" {
		return os.Getenv("EXEDIR")
	} else {
		return filepath.Dir(os.Args[0])
	}
}

AndreKR

# ZIP:
wget --header="PRIVATE-TOKEN: $GITLAB_TOKEN" "https://<gitlab>/<group>/<project>/builds/artifacts/master/download?job=<jobname>"
or
wget --header="PRIVATE-TOKEN: $GITLAB_TOKEN" "https://<gitlab>/<group>/<project>/-/jobs/artifacts/master/download?job=<jobname>"

# Single file:
wget -O /path/to/file --header="PRIVATE-TOKEN: $GITLAB_TOKEN" "https://<gitlab>/<group>/<project>/builds/artifacts/master/raw/<filename>?job=<jobname>"

AndreKR

// Initialize an empty image
dest := image.NewRGBA(image.Rect(0, 0, 800, 300))

// Draw a white background
draw.Draw(dest, dest.Bounds(), &image.Uniform{color.White}, image.ZP, draw.Src)

// Read the font

fontBytes, err := ioutil.ReadFile(exeDir + "/DejaVuSans.ttf")
if err != nil {