(YAML, TOML, JSON and env). There is no common answer. What extension should be used for creating a configuration file for a program? So its pretty clear how to get configs. Now with error monitoring and external services monitoring, Scout is a developer's best friend when it comes to application development. Viper will be able to read in a toml file, or in the env variables, so if you want to have a config file for your Development environment, but use the env vars, for Production, you can write a code like : Love podcasts or audiobooks? The JSON format worked for me quite well. Source code and other details for the project are available at GitHub: Usage please see example(more example please see examples folder in the lib): there are some event names for config data changed. To add a new package, please, check the contribute section. Here's the loading code I am using currently, which has default settings and allows command line flags (not shown) that override some of my config: https://github.com/spf13/viper and https://github.com/zpatrick/go-config are a pretty good libraries for configuration files. Support for JSON, TOML, YAML, env, command line, file, S3 etc. Kotlin SpringBoot App in Minikube Windows Cluster, How to deploy a Go application with Postgres on Patr, gRPC Interceptor: unary interceptor with code exampleTechdozo, //filename is the path to the json config file, configuration.Connection_String = os.Getenv("Connection_String"), Best practices for Configuration file in your code. It is a data interchange format - you may find losing the ability to write helpful/descriptive comments in config files can hurt maintainability ("why is this setting activated? //Checking that an environment variable is present or not. So the main idea is to get the application settings from where they are (file, env, remote server, etc.) ok is true, find value from config How to make config file in Golang elegantly? A lightweight yet powerful configuration manager for the Go programming language, A dead simple configuration manager for Go applications, read INI-style configuration files into Go structs; supports user-defined types and subsections, Small library to read your configuration from environment variables. Do not use Viper, it's not thread-safe which almost fired me. But both approaches have the same issue - a lot of magic inside. And will access them in a Go application using inbuilt and third-party packages. readable. I can't do that with JSON. But the target is the same - provide the app with a configuration, which is fast to get and easy to use. Connect and share knowledge within a single location that is structured and easy to search. Changelogs I agree with nemo and I wrote a little tool to make it all real easy. open source for accessing and storing configuration, Tag based configuration loader from different providers, (mirror) Configuration management software, infrastructure as file and directory layout, Golang struct-tag based configfile and flag parsing. Also, feel free to request any features you think may be helpful. // Environ returns a slice of string containing all the environment variables in the form of key=value. So, the app can have up to hundreds of variables it depends on. But work with configs is often tricky, in turn. Iniflags elegantly solves this problem: just modify two lines in your main package and it magically gains support for reading flag values from ini file. I noticed it was the method used by all the configuration options I could find. So in order to help those who dont want to manage 2 repositories , On our main.go (or in a config.go dedicated to manage all configuration), We should have a struct representing our configuration. It also allows environment variables to be loaded from the .env file. Uint get a int value, if not found return default value. Maybe others commit the same error > be warned ;D. I like TOML because it lets me write comments either on newlines or at the end of a line configuring setting. Int get a int value, if not found return default value. About 465), Design patterns for asynchronous API communication. The community reviewed whether to reopen this question 5 months ago and left it closed: Opinion-based Update the question so it can be answered with facts and citations by editing this post. WriteTo Write out config data representing the current state to a writer. As a nice developer, I always fight with implicitly. How to store Node.js deployment settings/configuration files? and send the filename and the struct to gonfig : So now we are able to manage conf like if we had only one config source. String get a string by key, if not found return default value, Strings get config data as a string slice/array. How to check if a map contains a key in Go? It is based on the git config format. Usage: LoadStrings load data from source string content. Support listen and fire events on config data changed. Find centralized, trusted content and collaborate around the technologies you use most. Flags provide standard 'help' output with default values and description. In my view, the only proper way to do that - add a full list of environment variables into a help output, including descriptions, default values and other meaningful information. How can I save application settings in a Windows Forms application? Use toml like this article Reading config files the Go way. Package toml is driver use TOML format content as config source Usage please see example: Package yaml is a driver use YAML format content as config source Usage please see example: Package yamlv3 is a driver use YAML format content as config source Usage please see example: // JSONAllowComments support write comments on json file. I have started using Gcfg which uses Ini-like files. For example, if you have this TOML data in something.toml, Then you can load it into your Go program with something like. The next no-magic step is the explicitness of variable names. Each approach has its own best practices. YAML is a human-readable data-serialization language. Do not miss the trending, packages, news and articles with our - Key is not case-sensitive when getting, Int64 get a int value, if not found return default value, IntMap get config data as a map[string]int, Ints get config data as a int slice/array, LoadExists load one or multi files, will ignore not exist, LoadExistsByFormat load one or multi files by give format, LoadFilesByFormat load one or multi files by give format. Ahhh - I tried that in my code and forgot to define the struct attributes with uppercase letters (not exported) - this cost me an hour of my life. Storing configuration in the environment is one of the principles of a twelve-factor app. Scout APM allows you to find and fix performance issues with no hassle. Flags have out-of-the-box support for default values and description. Decoder for decode yml,json,toml format content, Driver interface. Go Newsletter But you can handle them the right way too if you will read them once at the beginning. These are often used to make the same program behave differently in different deployment environments like PROD, DEV, or TEST. LoadExists load and parse config files, but will ignore not exists file. LoadRemote load config data from remote URL. and has a little bit less boilerplate (e.g., quotes around keys). He has since then inculcated very effective writing and reviewing culture at golangexample which rivals have found impossible to imitate. If you are managing variables in one place, in case of any changes, you don't have to change it in all the places in application code. I am pretty new to the Go world, so it might not be the Go way. I mean, can a newer version of the config file be used with older version of code? Personally i think it's easier for admins or customers to change a TOML file than a JSON. If you are using the sensitive information in the code, then all the unauthorized users who have access to the code will have sensitive data, you might not want that. They are used to work with only one config file. UCL is a bit like JSON, but with better support for humans: it supports comments and human-readable constructs like SI multipliers (10k, 40M, etc.) The main idea behind the cleanenv library is to make everything explicit and clean. An opinionated configuration loading framework for Containerized and Cloud-Native applications. MapOnExists mapping data to the dst structure only on key exists. Modules with tagged versions give importers more predictable builds. The downside is that you easily end up with a bunch of code to tell the user where the error was, various edge cases and what not. Categories :package: Clean APIs for your Go Applications, Go minimalist typed environment variables library, Library for easy configuration of a golang service, Viper wrapper with config inheritance and key generation. Its also a good place to write config documentation. Design: Initio by GetTemplate - Store supports either JSON, TOML or YAML out-of-the-box and lets you register practically any other configuration format. There are a lot of really good libraries for command-line argument handling like go-flags, and I dont think thats there is a reason to put everything in one single tool. Look, when I say its dead simple, I actually mean it: Store supports any other formats via the handy registration system: register the format once and youd be able to Load and Save files in it afterwards: John was the first writer to have joined golangexample.com. When a project reaches major version v1 it is considered stable.

Now you can manage environment variables in your go application, and You can found the complete code used in this tutorial on our Github Repo, Very curious about this world and blogging whenever learning something new. But there are still so many different ways to do so. For example, you may want to get configuration from a remote server, or some other tool, or update them. How else would your program be aware of the new config? ok is false, not found or error, Getenv get os ENV value by name.

But it works, it is pretty quick, and super simple to use. Notice: would suggest to use pflags instead of flags. the nice and informative help output; AddDriver set a decoder and encoder driver for a format. You define your config items in your application as a struct. I didnt like existing configuration management solutions like globalconf, tachyon or viper. About Viper supports many file formats to load environment variables, e.g., Reading from JSON, TOML, YAML, HCL, envfile and Java properties config files. A simple and zero-dependencies library to parse environment variables into structs. On your code you will need to declare your variables. YAML supports comments, if you want to add notes everywhere in config file. Provides CMDLine Args and Env args, Go module to build a decisional tree from a json, Gojest is like jest(nodejs) in golang, Press the `F` key to focus on your first error, Compares recent (07.2022) GPUs in performance and price (German market), A CLI tool to check the status of URLs on webpages, Reverse proxy to ethereum nodes. @BurntSushi5 can there be extra fields in the Toml file that the code does not care about? support JSON, YAML, TOML, INI, HCL, ENV and Flags. How can recreate this bubble wrap effect on my photos? It persists all of your configurations in either $XDG_CONFIG_HOME or $HOME on Linux and in %APPDATA% on Windows. Story: man purchases plantation on planet, finds 'unstoppable' infestation, uses science, electrolyses water for oxygen, 1970s-1980s. I started using flags for a project I've been working on (my first from-scratch golang project), but I'm wondering how to handle things like tests? LoadFlags parse command line arguments, based on provide keys. I looked into go-yaml and it's a valiant effort, but i took the lack of documentation as an indication that i should look elsewhere. TODO refactor: rename GetDecoder() to Decode(), rename GetEncoder() to Encode(), Encoder for decode yml,json,toml format content, These are some sample code for YAML,TOML,JSON,INI,HCL, Package dotnev provide load .env data to os ENV Deprecated: please use github.com/gookit/ini/v2/dotenv, Package hcl is driver use HCL format content as config source about HCL, please see https://github.com/hashicorp/hcl, Package hclv2 is driver use HCL format content as config source about HCL, please see https://github.com/hashicorp/hcl docs for HCL v2 https://pkg.go.dev/github.com/hashicorp/hcl/v2, Package ini is driver use INI format content as config source about ini parse, please see https://github.com/gookit/ini/parser, Package json use the https://github.com/json-iterator/go for parse json, Package json5 use the https://github.com/yosuke-furukawa/json5 for parse json5, Package other is an example of a custom driver. automatic mirror of https://git.sr.ht/~spc/go-ini. Not a good idea when you need to share config with other pieces of application written in another languages. Everything goes clean and visible. I would never expect a config loading library to be safe for concurrent use. Pretty useful, but very implicit. How to avoid annoying error "declared and not used", Pointers vs. values in parameters and return values, Function declaration syntax: things in parenthesis before function name. There is something I really dont like - environment variables because they are the same bad as global variables. go-up! Genv is a library for Go (golang) that makes it easy to read and use environment variables in your projects. Its okay in my case to ignore unused config options. Recently I need an INI parser with section support, and I write a simple package: u can parse INI like using "flag" package: You might also be interested in go-libucl, a set of Go bindings for UCL, the Universal Configuration Language. ", "what does it do? Why is rapid expansion/compression reversible? Overall, it provides you with easy configuration, better security, multiple deployment environments and fewer production mistakes. Support data overlay and merge, automatically load by key when loading multiple copies of data, Support for binding all or part of the configuration data to the structure, Support parse ENV name and allow with default value. no magic, explicit way to read and use configuration; See also https://groups.google.com/forum/#!topic/golang-nuts/TByzyPgoAQE for details. Multi file load, data override merge, parse ENV var. So getting variables from a conf file, and from the environment as well. mv fails with "No space left on device" when the destination has 31 GB of space remaining, Cannot handle OpenDirect push notification when iOS app is not launched. os.Getenv() will return an empty string if the environment variable is not present, to distinguish between an empty value and an unset value, use LookupEnv. So we have to get information from the json : have a static configuration context allowing you to have all the configuration everywhere in your app. Instantiate/configure structs recursively, based on build environment. // contains filtered or unexported fields, // parse env value. Pass environment variables from docker to my GoLang. There are some ways to write your own logic to read the data from your own source. Normally, the app uses either a command-line approach (CLI tools) or config file + environment approach (web services, containerized apps, etc.). Isn't this exactly what Ask mentioned already? Learn about environment variables and different ways to use them in your Golang application. It enables applications to be portable. And thats why a structured format was chosen as a base for configuration. But I hate having to create the struct of the exact fields and types I might be setting. Maybe my background in dynamic languages makes me blind to the benefits of such verboseness. Golang's application config manage tool library, Manage local application configuration files using templates and data from etcd or consul, Application for HTTP benchmarking via different rules and configs, A handy utility to generate configmap and values.yaml of your application for helmifying them, Viper: a complete configuration solution for Go applications including 12-Factor apps, Algorand-MultiSig - An open source repo that allows Algorand devs to easily spin up an application that enables multi-sig signing, A Go application for Rust game servers operating with Pterodactyl. and distribute them through the app, to make them available wherever they are required. The collection of libraries and resources is based on the Modern containerizable applications use environment variables as the main configuration.

Environment variables are easy to change between deploys without changing any application code. @Dr.eel Try separate viper.GetBool("abc") and Viper.Set("abc", false) in different goroutine.

Why had climate change not been proven beyond doubt for so long? For example, this is an api client, and I'd like to use flags, but it seems like it would over complicate my testing (, would be very helpful if there were detailed example code here showing a working example :). I havent found anything not overcomplicated but still useful, with explicit configuration setup and clean and informative help output, so Ive built it on my own. Below is the output when we run go run main.go in our terminal. There are two more functions os.Clearenv and os.Environ() let's use them also in a separate program. Redistributable licenses place minimal restrictions on how software can be used, Now we use such things as configuration files, environment variables, command-line parameters, as well as CI configuration patterns and on-fly config file builds, remote config servers, specific mapping, and binding services and even more complex things. This one is good, since I don't have to redefine entire config structure in go, How to handle configuration in Go [closed], Persisting Application Configuration In Go, https://groups.google.com/forum/#!topic/golang-nuts/TByzyPgoAQE, Learn more about Collectives on Stack Overflow, How APIs can take the pain out of legacy system headaches (Ep. It's simple - if you want something simple, this is a good choice. So in this example, we will look at how to load environment variables from a YAML file. easy integration with other libraries. It has a lot of boilerplate, the type system isnt so much forgivable, and OOP possibilities are very limited. So, Im happy if it will help you. And here we are: cleanenv library is now released and proven in production. It seems that JSON is the least bad of the current alternatives. Read more in documentation. modified, and redistributed. godotenv also supports YAML. like. i like it.

while offering semantics for lists and mappings (which can become quite handy), which If we want to implement the best practices for manage our conf files. // You must init store with some truly unique path first! like: "${EnvName}" "${EnvName|default}", // parse key, allow find value by key path. we can load multiple env files at once also. I wrote a simple ini config library in golang. No global state, no encapsulated maps, no magical background updates nether any other hidden work. But there is a nice thing that worth it - it is instantly readable, it has no magic inside. Let's create a .env file in which we will have all our configurations. Let's create our config.yaml and main.go in an empty folder. Golang's application config manage tool library. Your configuration should probably be loaded at the beginning of your program, and the values then passed to your dependencies. Here is an example of a simple server configuration structure: This structure can be used to parse YAML configuration file, and then read some data from the environment. It also supports slice values, so you can allow specifying a key multiple times and other nice features like that. I dont use global variables, I structure my code the readable way and may my code flow certain and clear. But how to do that? Store is a dead simple configuration manager for Go applications. I tend to use shell scripts and environment variables. Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. default is '. MapStruct alias method of the 'Structure', ParseEnvVarStringHookFunc returns a DecodeHookFunc that parse ENV var, StringMap get config data as a map[string]string, Uint get a uint value, if not found return default value, NewWith create config instance, and you can call some init func. The structure (as deep and complex as you want) being used to parse configuration files and environment variables. Simple, useful and opinionated config loader. All content is licensed under Creative Commons Attribution 3.0, Copyright 2017-2021, Ilya Kaznacheev Configure Go applications from the environment. This package is not in the latest version of its module. First, it will read the file, and then try to find environment variables using names in env tags. Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. Handling configurations without defining explicit type objects. in cricket, is it a no-ball if the batsman advances down the wicket and meets fulltoss ball above his waist. If you are using the code versioning tool like. We can also set the default values for any environment variable if any environment variable is not available in the config file. You don't need any external package to access the environment variables in Golang, and you can do that with the standard os package. You can now choose to sort by Trending, which boosts votes that have happened recently, helping to surface more up-to-date answers. It's actually pretty close to the nginx configuration file format, if you're already familiar with that. There a couple of reasons: handle config files and environment variables, not command-line parameters; // Get the value of an Environment Variable. Simple, lightweight, extensible, configuration management library for Go. Good work. Some libraries (like viper store configs as a key-value set in a global area. You can manage multiple deployment environments like PROD, DEV, or TEST. weekly report. JavaScript front end for Odin Project book library database. Initializing a new Go configuration with Viper. This script will find all of the configuration version left in TFC, Trivial proxy server that logs requests and responses to stdout, List Process In Table, Search and Filter by Name, PID, PPID, User. Within big projects sometimes you can just lose the way how one or another variable came to this state. Site Links: is not the case with many ini-type config parsers. Once we run os.Clearenv() it will clear all the environment variables for the running process. Harvest configuration, watch and notify subscriber, Go package that interfaces with AWS System Manager, A golang package for parsing ini-style configuration files, Un-marshaling environment variables to Go structs. Never forget to include your environment variable files in the .gitignore. For base configuration (api keys, port numbers, ) I've had very good luck with the gcfg package. ", "what are valid values for it?" Go isnt a language for everyone. But what to do next? Easy to use. Why? Loading configuration in separate goroutines is probably the wrong way to do it. // we keep it empty it will load .env from current directory, // getting env variables SITE_TITLE and DB_HOST, // Set the file name of the configurations file, // Set the path to look for the configurations file, // Enable VIPER to read Environment Variables, // viper.Get() returns an empty interface{}, // so we have to do the type assertion, to get the value, // if type assert is not valid it will throw an error, M2M Authorization: Authenticate Apps, APIs, and Web Services, Implement HTTP Streaming with Node.js and Fetch API, NestJS: How to Implement Session-Based User Authentication, How to Integrate Invisible reCAPTCHA for Bot Protection, Latest Golang version installed on your system. Modular JSON configuration. Standard go flags have the following benefits: The only drawback standard go flags have - is management problems when the number of flags used in your app becomes too large. But I want not only to give a simple tool but also to make it easy to use with other codes. As an Amazon Associate, we earn from qualifying purchases. Go. Currently just working for beacon nodes, Package go-unzip provides a very simple library to extract zip archive, A repository of example implementations of using AWS CDK with Go language, Neutrino CloudSync - An open-source tool used to upload entire file folders from any host to any cloud, OpenTelemetry Tracing instrumentation for PostgreSQL, A collactz conjecture service running in kubernets, SSE Client for Flashbots Relayer Data, written in go, Header Block - A middleware plugin for Traefik to block request and response headers which regex matched, A rootless container system written in Go following along Liz Rice's presentation at the goto conference, Lifecycle management of OS2mo entities using the GraphQL API, GSP761 Developing a REST API with Go and Cloud Run, A simulation to show what happens if to switch in Monty Hall problem using Go, Ability to swap out skate.ea graphics with custom ones. ', // DecoderConfig setting for binding data to struct, (c) LoadExistsByFormat(format, sourceFiles), (c) LoadFilesByFormat(format, sourceFiles), https://github.com/JanDeDobbeleer/oh-my-posh, func BindStruct(key string, dst interface{}) error, func Bool(key string, defVal bool) bool, func DumpTo(out io.Writer, format string) (int64, error), func Exists(key string, findByPath bool) bool, func Float(key string, defVal float64) float64, func Get(key string, findByPath bool) interface{}, func GetEnv(name string, defVal string) (val string), func GetValue(key string, findByPath bool) (interface{}, bool), func Getenv(name string, defVal string) (val string), func Int64(key string, defVal int64) int64, func LoadData(dataSource interface{}) error, func LoadExists(sourceFiles string) error, func LoadExistsByFormat(format string, sourceFiles string) error, func LoadFiles(sourceFiles string) error, func LoadFilesByFormat(format string, sourceFiles string) error, func LoadOSEnv(keys []string, keyToLower bool), func LoadRemote(format, url string) error, func LoadSources(format string, src []byte, more []byte) error, func LoadStrings(format string, str string, more string) error, func MapOnExists(key string, dst interface{}) error, func MapStruct(key string, dst interface{}) error, func ParseEnvVarStringHookFunc() mapstructure.DecodeHookFunc, func Set(key string, val interface{}, setByPath bool) error, func SetData(data map[string]interface{}), func SetDecoder(format string, decoder Decoder), func SetEncoder(format string, encoder Encoder), func String(key string, defVal string) string, func StringMap(key string) map[string]string, func Uint(key string, defVal uint) uint, func WithHookFunc(fn HookFunc) func(*Options), func WriteTo(out io.Writer) (int64, error), func NewWith(name string, fn func(c *Config)) *Config, func NewWithOptions(name string, opts func(*Options)) *Config, func (c *Config) AddDriver(driver Driver), func (c *Config) BindStruct(key string, dst interface{}) error, func (c *Config) Bool(key string, defVal bool) (value bool), func (c *Config) Data() map[string]interface{}, func (c *Config) DelDriver(format string), func (c *Config) DumpTo(out io.Writer, format string) (n int64, err error), func (c *Config) Exists(key string, findByPath bool) (ok bool), func (c *Config) Float(key string, defVal float64) (value float64), func (c *Config) Get(key string, findByPath bool) interface{}, func (c *Config) GetValue(key string, findByPath bool) (value interface{}, ok bool), func (c *Config) HasDecoder(format string) bool, func (c *Config) HasEncoder(format string) bool, func (c *Config) Int(key string, defVal int) (value int), func (c *Config) Int64(key string, defVal int64) (value int64), func (c *Config) IntMap(key string) (mp map[string]int), func (c *Config) Ints(key string) (arr []int), func (c *Config) LoadData(dataSources interface{}) (err error), func (c *Config) LoadExists(sourceFiles string) (err error), func (c *Config) LoadExistsByFormat(format string, sourceFiles string) (err error), func (c *Config) LoadFiles(sourceFiles string) (err error), func (c *Config) LoadFilesByFormat(format string, sourceFiles string) (err error), func (c *Config) LoadFlags(keys []string) (err error), func (c *Config) LoadOSEnv(keys []string, keyToLower bool), func (c *Config) LoadRemote(format, url string) (err error), func (c *Config) LoadSources(format string, src []byte, more []byte) (err error), func (c *Config) LoadStrings(format string, str string, more string) (err error), func (c *Config) MapOnExists(key string, dst interface{}) error, func (c *Config) MapStruct(key string, dst interface{}) error, func (c *Config) Set(key string, val interface{}, setByPath bool) (err error), func (c *Config) SetData(data map[string]interface{}), func (c *Config) SetDecoder(format string, decoder Decoder), func (c *Config) SetDecoders(decoders map[string]Decoder), func (c *Config) SetEncoder(format string, encoder Encoder), func (c *Config) SetEncoders(encoders map[string]Encoder), func (c *Config) String(key string, defVal string) string, func (c *Config) StringMap(key string) (mp map[string]string), func (c *Config) Strings(key string) (arr []string), func (c *Config) Structure(key string, dst interface{}) error, func (c *Config) Uint(key string, defVal uint) (value uint), func (c *Config) With(fn func(c *Config)) *Config, func (c *Config) WithOptions(opts func(*Options)) *Config, func (c *Config) WriteTo(out io.Writer) (n int64, err error), func NewDriver(name string, dec Decoder, enc Encoder) *StdDriver, func (d *StdDriver) Decode(blob []byte, v interface{}) (err error), func (d *StdDriver) Encode(v interface{}) ([]byte, error).