Elian Harber

Elian Harber

1652933532

Delve: A Debugger for The Go Programming Language

Delve is a debugger for the Go programming language. The goal of the project is to provide a simple, full featured debugging tool for Go. Delve should be easy to invoke and easy to use. Chances are if you're using a debugger, things aren't going your way. With that in mind, Delve should stay out of your way as much as possible.

The GitHub issue tracker is for bugs only. Please use the developer mailing list for any feature proposals and discussions.

About Delve

Installation

Directions for installing Delve on all supported platforms is provided here.

Please note you must have Go 1.10 or higher installed in order to compile Delve.

Getting Started

Delve aims to be a very simple and powerful tool, but can be confusing if you're not used to using a source level debugger in a compiled language. This document will provide all the information you need to get started debugging your Go programs.

Debugging 'main' packages

The first CLI subcommand we will explore is debug. This subcommand can be run without arguments if you're in the same directory as your main package, otherwise it optionally accepts a package path.

For example given this project layout:

.
├── github.com/me/foo
├── cmd
│   └── foo
│       └── main.go
├── pkg
│   └── baz
│       ├── bar.go
│       └── bar_test.go

If you are in the directory github.com/me/foo/cmd/foo you can simple run dlv debug from the command line. From anywhere else, say the project root, you can simply provide the package: dlv debug github.com/me/foo/cmd/foo. To pass flags to your program separate them with --: dlv debug github.com/me/foo/cmd/foo -- -arg1 value.

Invoking that command will cause Delve to compile the program in a way most suitable for debugging, then it will execute and attach to the program and begin a debug session. Now, when the debug session has first started you are at the very beginning of the program's initialization. To get to someplace more useful you're going to want to set a breakpoint or two and continue execution to that point.

For example, to continue execution to your program's main function:

$ dlv debug github.com/me/foo/cmd/foo
Type 'help' for list of commands.
(dlv) break main.main
Breakpoint 1 set at 0x49ecf3 for main.main() ./test.go:5
(dlv) continue
> main.main() ./test.go:5 (hits goroutine(1):1 total:1) (PC: 0x49ecf3)
     1:	package main
     2:	
     3:	import "fmt"
     4:	
=>   5:	func main() {
     6:		fmt.Println("delve test")
     7:	}
(dlv)

Debugging tests

Given the same directory structure as above you can debug your code by executing your test suite. For this you can use the dlv test subcommand, which takes the same optional package path as dlv debug, and will also build the current package if not given any argument.

$ dlv test github.com/me/foo/pkg/baz
Type 'help' for list of commands.
(dlv) funcs test.Test*
/home/me/go/src/github.com/me/foo/pkg/baz/test.TestHi
(dlv) break TestHi
Breakpoint 1 set at 0x536513 for /home/me/go/src/github.com/me/foo/pkg/baz/test.TestHi() ./test_test.go:5
(dlv) continue
> /home/me/go/src/github.com/me/foo/pkg/baz/test.TestHi() ./bar_test.go:5 (hits goroutine(5):1 total:1) (PC: 0x536513)
     1:	package baz
     2:	
     3:	import "testing"
     4:	
=>   5:	func TestHi(t *testing.T) {
     6:		t.Fatal("implement me!")
     7:	}
(dlv)

As you can see, we began debugging the test binary, found our test function via the funcs command which takes a regexp to filter the list of functions, set a breakpoint and then continued execution until we hit that breakpoint.

For more information on subcommands you can use type dlv help, and once in a debug session you can see all of the commands available to you by typing help at any time.

Delve Documentation

Documentation for the project will reside in this directory.

Contributing to Delve

Want to help contribute to Delve? Great! Any and all help is certainly appreciated, whether it's code, documentation, or spelling corrections.

If you are planning to contribute a significant change, please draft a design document (or start a conversation) and post it to the developer mailing list. This will allow other developers and users to discuss the proposed change.

Filing issues

When filing an issue, make sure to answer these six questions:

  1. What version of Delve are you using (dlv version)?
  2. What version of Go are you using? (go version)?
  3. What operating system and processor architecture are you using?
  4. What did you do?
  5. What did you expect to see?
  6. What did you see instead?

Contributing code

Fork this repo and create your own feature branch. Install all dependencies as documented in the README.

Guidelines

Consider the following guidelines when preparing to submit a patch:

  • Follow standard Go conventions (document any new exported types, funcs, etc.., ensuring proper punctuation).
  • Ensure that you test your code. Any patches sent in for new / fixed functionality must include tests in order to be merged into master.
  • If you plan on making any major changes, create an issue before sending a patch. This will allow for proper discussion beforehand.
  • Keep any os / arch specific code contained to os / arch specific files. Delve leverages Go's filename based conditional compilation, i.e do not put Linux specific functionality in a non Linux specific file.

Format of the Commit Message

We follow a rough convention for commit messages that is designed to answer two questions: what changed and why. The subject line should feature the what and the body of the commit should describe the why.

terminal/command: Add 'list' command

This change adds the 'list' command which will print either your current
location, or the location that you specify using the Delve linespec.

Fixes #38

The format can be described more formally as follows:

<subsystem>: <what changed>
<BLANK LINE>
<why this change was made>
<BLANK LINE>
<footer>

The first line is the subject and should be no longer than 70 characters, the second line is always blank, and other lines should be wrapped at 80 characters. This allows the message to be easier to read on GitHub as well as in various git tools.

Author: Derekparker
Source Code: https://github.com/derekparker/delve 
License: MIT license

#go #golang 

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Buddha Community

Delve: A Debugger for The Go Programming Language
Cayla Erdman

Cayla Erdman

1594369800

Introduction to Structured Query Language SQL pdf

SQL stands for Structured Query Language. SQL is a scripting language expected to store, control, and inquiry information put away in social databases. The main manifestation of SQL showed up in 1974, when a gathering in IBM built up the principal model of a social database. The primary business social database was discharged by Relational Software later turning out to be Oracle.

Models for SQL exist. In any case, the SQL that can be utilized on every last one of the major RDBMS today is in various flavors. This is because of two reasons:

1. The SQL order standard is genuinely intricate, and it isn’t handy to actualize the whole standard.

2. Every database seller needs an approach to separate its item from others.

Right now, contrasts are noted where fitting.

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Fannie Zemlak

Fannie Zemlak

1599854400

What's new in the go 1.15

Go announced Go 1.15 version on 11 Aug 2020. Highlighted updates and features include Substantial improvements to the Go linker, Improved allocation for small objects at high core counts, X.509 CommonName deprecation, GOPROXY supports skipping proxies that return errors, New embedded tzdata package, Several Core Library improvements and more.

As Go promise for maintaining backward compatibility. After upgrading to the latest Go 1.15 version, almost all existing Golang applications or programs continue to compile and run as older Golang version.

#go #golang #go 1.15 #go features #go improvement #go package #go new features

Biju Augustian

Biju Augustian

1574340419

Guide to Python Programming Language

Description
The course will lead you from beginning level to advance in Python Programming Language. You do not need any prior knowledge on Python or any programming language or even programming to join the course and become an expert on the topic.

The course is begin continuously developing by adding lectures regularly.

Please see the Promo and free sample video to get to know more.

Hope you will enjoy it.

Basic knowledge
An Enthusiast Mind
A Computer
Basic Knowledge To Use Computer
Internet Connection
What will you learn
Will Be Expert On Python Programming Language
Build Application On Python Programming Language

#uide to Python #Guide to Python Programming #Guide to Python Programming Language #Python Programming #Python Programming Language

Zander Herzog

Zander Herzog

1596793260

Secure HTTPS servers in Go

In this article, we are going to look at some of the basic APIs of the http package to create and initialize HTTPS servers in Go.

Image for post

(source: unsplash.com)

In the “Simple Hello World Server” lesson, we learned about net/http package, how to create routes and how [ServeMux](https://golang.org/pkg/net/http/#ServeMux) works. In the “Running multiple HTTP servers” lesson, we learned about [Server](https://golang.org/pkg/net/http/#Server) structure and how to run multiple HTTP servers concurrently.

In this lesson, we are going to create an HTTPS server using both Go’s standard server configuration and custom configuration (using [_Server_](https://golang.org/pkg/net/http/#Server) structure). But before this, we need to know what HTTPS really is?

HTTPS is a big topic of discussion in itself. Hence while writing this lesson, I published an article just on “How HTTPS works?”. I advise you to read this lesson first before continuing this article. In this article, I’ve also described the encryption paradigm and SSL certificates generation process.

If we recall the simplest HTTP server example from previous lessons, we only need http.``[ListenAndServe](https://golang.org/pkg/net/http/#ListenAndServe) function to start an HTTP server and http.``[HandleFunc](https://golang.org/pkg/net/http/#HandleFunc) to register a response handler for a particular endpoint.

Image for post

(https://play.golang.org/p/t3sOenOYAzS)

In the example above, when we run the command go run server.go , it will start an HTTP server on port 9000. By visiting http://localhost:9000 URL in a browser, you will be able to see a Hello World! message on the screen.

Image for post

(http://localhost:9000)

As we know, the nil argument to ListenAndServe() call invokes Go to use the [DefaultServeMux](https://golang.org/pkg/net/http/#DefaultServeMux) response multiplexer, which is the default instance of ServeMux structure provided globally by the Go. The HandleFunc() call adds a response handler for a specific route on the multiplexer instance.

The http.ListenAndServe() call uses the Go’s standard HTTP server configuration, however, in the previous lesson, how we can customize a server using [Server](https://golang.org/pkg/net/http/#Server) structure type.

To start an HTTPS server, all we need do is to call ServerAndListenTLS method with some configuration. Just like ServeAndListen method, this method is available on both the http package and the Server structure.

The http.``[ServeAndListenTLS](https://golang.org/pkg/net/http/#ListenAndServeTLS) method uses the Go’s standard server implementation, however, both [Server](https://golang.org/pkg/net/http/#Server) instance and Server.``[ServeAndListenTLS](https://golang.org/pkg/net/http/#Server.ListenAndServeTLS) method can be configured for our needs.

#go-programming-language #go #golang-tutorial #go-programming #golang

Brando Dietrich

Brando Dietrich

1589642959

Learning Go — Array, Slice, Map

We have already seen how to create and work with variables, pointers, and Constants. In this article, we are going to see the four important collection types built into the language.
We start with humble Arrays, from there we move on to Slice, an evolved version of Array. From Slice, we talk about the map a key-value pair collection. Let’s start with Arrays here.

#golang-tutorial #golang #go-programming #go-programming-language #programming