golang

Links

• https://golang.org/
• https://tour.golang.org/welcome/1
• https://godoc.org/
• https://golang.org/pkg/
• https://golang.org/doc/#articles
• https://github.com/avelino/awesome-go
• Project Layout

Workplace Setup

• https://golang.org/doc/code.html

Webstuff

• http://nicolasmerouze.com/share-values-between-middlewares-context-golang/
• https://github.com/astaxie/build-web-application-with-golang/blob/master/en/preface.md
• https://grafana.com/blog/2024/02/09/how-i-write-http-services-in-go-after-13-years/
• https://quii.gitbook.io/learn-go-with-tests/

FMT

• https://golang.org/pkg/fmt/

General:

%v  the value in a default format
    when printing structs, the plus flag (%+v) adds field names
%#v a Go-syntax representation of the value
%T  a Go-syntax representation of the type of the value
%%  a literal percent sign; consumes no value
Boolean:

%t  the word true or false
Integer:

%b  base 2
%c  the character represented by the corresponding Unicode code point
%d  base 10
%o  base 8
%q  a single-quoted character literal safely escaped with Go syntax.
%x  base 16, with lower-case letters for a-f
%X  base 16, with upper-case letters for A-F
%U  Unicode format: U+1234; same as "U+%04X"
Floating-point and complex constituents:

%b  decimalless scientific notation with exponent a power of two,
    in the manner of strconv.FormatFloat with the 'b' format,
    e.g. -123456p-78
%e  scientific notation, e.g. -1234.456e+78
%E  scientific notation, e.g. -1234.456E+78
%f  decimal point but no exponent, e.g. 123.456
%F  synonym for %f
%g  %e for large exponents, %f otherwise
%G  %E for large exponents, %F otherwise
String and slice of bytes:

%s  the uninterpreted bytes of the string or slice
%q  a double-quoted string safely escaped with Go syntax
%x  base 16, lower-case, two characters per byte
%X  base 16, upper-case, two characters per byte
Pointer:

%p  base 16 notation, with leading 0x

Libraries

• Die Bibliothek compilieren: go build pfad/ohne/$GOPATH/$projectname/

  Danach muss die Bibliothek installiert werden: go install pfad/wie/oben

  Sie kann auch getestet werden: https://golang.org/doc/code.html#Testing

Generate 2 dimensional Array at Runtime

• http://rosettacode.org/wiki/Create_a_two-dimensional_array_at_runtime#Go

Gin Framework

• https://godoc.org/github.com/gin-gonic/gin
• https://github.com/gin-gonic/gin

DB

• https://golang.org/pkg/database/sql/

• https://github.com/lib/pq

• https://godoc.org/github.com/lib/pq

  Multiple Values:

• https://stackoverflow.com/questions/17845619/how-to-call-the-scan-variadic-function-in-golang-using-reflection

• http://jordanorelli.com/post/32665860244/how-to-use-interfaces-in-go

Delve Debugger

• https://github.com/go-delve/delve/blob/master/Documentation/cli/getting_started.md
• cli-Reference: https://github.com/go-delve/delve/tree/master/Documentation/cli

dlv debug main.go

b main.go:7 # set breakpoint in file on line 7
step/s
rebuild
args # print arguments
locals # print locals
print var # print the variable
print resp.Status
whatis resp # show type of variable
list # print source code
disassemble

• CTRL-r works for reverse search