mg-transport-core/README.md

Message Gateway Transport Library

This library provides different functions like error-reporting, logging, localization, etc. in order to make it easier to create transports.
Usage:

package main

import (
    "os"
    "fmt"
    "html/template"

    "github.com/gin-gonic/gin"
    "github.com/gobuffalo/packr/v2"
    "github.com/retailcrm/mg-transport-core/core"
)

func main() {
    // Create new core.Engine instance
    app := core.New()

    // Load configuration
    app.Config = core.NewConfig("config.yml")

    // Set default error translation key (will be returned if something goes wrong)
    app.DefaultError = "unknown_error"

    // Set translations path
    app.TranslationsPath = "./translations"

    // Preload some translations so they will not be loaded for every request
    app.PreloadLanguages = core.DefaultLanguages
    
    // Configure gin.Engine inside core.Engine
    app.ConfigureRouter(func(engine *gin.Engine) {
        engine.Static("/static", "./static")
        engine.HTMLRender = app.CreateRenderer(
]           // Insert templates here. Custom functions also can be provided.
            // Default transl function will be injected automatically
            func(renderer *core.Renderer) {
                // Push method will load template from FS or from binary
                r.Push("home", "templates/layout.html", "templates/home.html")
            }, 
            template.FuncMap{},
        )
    })
    
    // Start application or fail if something gone wrong (e.g. port is already in use)
    if err := app.Prepare().Run(); err != nil {
        fmt.Printf("Fatal error: %s", err.Error())
        os.Exit(1)
    }
}

Resource embedding

packr can be used to provide resource embedding. In order to use packr you must follow this instruction, and provide boxes with templates, translations and assets to library. Example:

package main

import (
    "os"
    "fmt"
    "html/template"

    "github.com/gin-gonic/gin"
    "github.com/gobuffalo/packr/v2"
    "github.com/retailcrm/mg-transport-core/core"
)

func main() {
    static := packr.New("assets", "./static")
    templates := packr.New("templates", "./templates")
    translations := packr.New("translations", "./translate")
    
    app := core.New()
    app.Config = core.NewConfig("config.yml")
    app.DefaultError = "unknown_error"

    // Now translations will be loaded from packr.Box
    app.TranslationsBox = translations
    app.PreloadLanguages = core.DefaultLanguages
    
    app.ConfigureRouter(func(engine *gin.Engine) {
        // gin.Engine can use packr.Box as http.FileSystem
        engine.StaticFS("/static", static)
        engine.HTMLRender = app.CreateRendererFS(
            templates, 
            func(renderer *core.Renderer) {
                // Same Push method here, but without relative directory.
                r.Push("home", "layout.html", "home.html")
            }, 
            template.FuncMap{},
        )
    })
    
    if err := app.Prepare().Run(); err != nil {
        fmt.Printf("Fatal error: %s", err.Error())
        os.Exit(1)
    }
}

Migration generator

This library contains helper tool for transports. You can install it via go:

$ go get -u github.com/retailcrm/mg-transport-core/cmd/transport-core-tool

Currently, it only can generate new migrations for your transport.