![]() It looks a bit like this: `Įrr := json.Unmarshal(textBytes, &people1) Let's take an API from the Open Notify group - it shows the of people in space and their names. If a document doesn't fit into the structure it will throw an error. Let's go on to parse some JSON, in Go we can turn a JSON document into a struct which is useful for accessing the data in a structured way. Go applications can also be cross-compiled for other operating systems without any further changes, here's how you can build the above code for Windows: GOOS=windows go build -o hello-world.exe The -w command writes the change to the file. ![]() Go offers a convention-based formatting of files, you can format a file and its indentation with: gofmt -s -w app.go Now you can build and run the code again, note that you can also change the output of the binary when compiled: go build -o hello-world Go ahead and run the program, you have two ways to do this: go run app.go This program is effectively hello-world without any print statements. Now save a new file named app.go: package main Make yourself a folder for a new project (you can use your Github username here): mkdir -p $GOPATH/src//alexellis/blank/ If you're using Visual Studio Code, let it install the plugins it suggests such as gofmt because they will ensure your code looks good. I have had good experiences using nano and vim, but Visual Studio Code is probably the easiest to setup with a good Go experience. We are going to use the Golang standard library which has a number of useful components for HTTP and JSON, so no external dependencies will be required. If you want the change to stick, add the line to.Set a GOPATH - this was a required step in 2017 when the post was original written, and is still my preferred style, so we will stick with it. Check your Go installation with go version.You may also like my new ebook - Everyday Golang which is full of practical examples and tips from open-source Go applications including JSON, HTTP servers, embedding, databases, templates and Goroutines. Updated: June 2020 - newer Go version, updated the introduction and code example. ![]() We will be querying an endpoint provided for free that tells us how many astronauts are currently in space and what their names are. These are just a subset of the possible events you can use to track your outgoing HTTP requests in Go.This is a recipe in Golang for making a "GET" request over HTTP to an API on the Internet. Any particular hook may be nil type ClientTrace struct This is a stripped-down version of the httptrace.ClientTrace structĬlientTrace is a set of hooks to run at various stages of an outgoing HTTP request. ![]() Those events are defined as functions and also known as “hooks”. It is used to define the events we want to listen to. The main exported type from the httptrace package is the ClientTrace struct type. In this artice we are going to have a look at how to use the httptrace package to monitor the performance of our Go (Golang) http requests. For example, dns resolution, tcp connection creation, data written to the tcp connection, data received from the tcp connection and so on. The main idea is the ability to track a set of events that occur within a lifecycle of a http request. The package is extremely useful if you want to monitor the performance of your http requests or if you want to collect and monitor statistics about your http clients. The httptrace package is a new package included in the Go (Golang) standard library from Go1.7. ![]()
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