Everyday Golang - The Fast Track

 Introduction....6 How to use the book....6 Help the book to evolve....7 Changelog....7 Why Go?....7 Getting started with Go....8 A note for Windows users....9 Direct installation on Linux....9 Packages and paths....9 Vendoring and Go modules....11 Create your first Go program....13 Add an external dependency....14 Make use of flags....16 Define a separate package or library....18 Cross-compile for different operating systems....22 Go build arguments....22 CGO and portability....23 Fetch JSON from a HTTP endpoint....24 Get started....24 Learn to parse JSON....25 Retrieve the JSON via HTTP....26 Extracting additional data from the JSON....29 Five ways to write an awesome CLI....31 Pick Go....31 Parse flags & arguments....32 Automate everything....33 Integrate with package managers....34 Accept contributions and gather feedback....35 Now, Go and write your CLI....35 Writing unit-tests in Golang....36 Testing opinions....36 Testing the Sum method....38 Adding a test table....40 Party tricks for ``go test''....41 Statement coverage....41 Generating an HTML coverage report....41 Benchmarking your code....42 Go doesn't ship your tests....43 Stress testing your tests....43 Running tests in parallel....43 Compile the tests to a binary....47 Isolating dependencies....48 Example of isolating dependencies....50 Unit-testing a HTTP server....52 Work concurrently work with Goroutines....56 A simple example with Goroutines....56 Avoid a common mistake with Goroutines....58 Error groups....60 Limiting requests to expensive resources....61 Sharing data between Goroutines....65 Using channels for synchronisation....68 Using a context to handle timeouts....70 Limiting concurrent work....72 Store data with a database....77 Write your own config files in YAML....82 A practical example of YAML in action....82 Read and write your own YAML schema....82 Merging objects....84 Inject version information into your binaries....87 Capture useful variable(s)....87 Prepare your code....88 Do it with Docker....90 Examples in production....90 Embed data in your application....92 Create dynamic content with templates....94 Advanced templates: ranges and custom functions....95 Real-world templates - arkade....97 Write a HTTP server....100 Reading the request....101 Advanced route handling....102 Writing HTTP middleware....104 Add Prometheus metrics to your microservices....106 Tracking HTTP metrics for our microservice....111 Adding custom metrics to your Prometheus data....114 The Prometheus Collector interface....116 Building and releasing Go binaries....120 The release-it example....120 Releasing your binaries with a GitHub Action....121 Releasing a Docker container image....123 Going multi-arch....124 Shipping a Docker container from GitHub Actions....125 Your onward journey....127 Giving feedback....127 Contributing to Open Source....127 My other content....127 OpenFaaS and Go....128 Topics covered....128 Serverless use-cases....128 Introduction to OpenFaaS....129 The value vs cloud functions....129 Pros and Cons....130 Where can you run OpenFaaS functions?....130 The Go template for OpenFaaS....130 Your first function....132 Building your function....134 Adding unit tests to your function....135 Iterating locally....136 Split code into multiple files....137 Introduce a sub-package....139 Working with secrets and databases....140 Create the todo-fn example....140 Exploring the request....143 The complete example....149 Managing config between multiple environments....154 Futher tasks....154 Custom domains and routes....155 Where to go next....157