How can I use TOML fixtures to seed my database in a development environment using the Go Buffalo framework?

Question

I am trying to seed my development database in the Go Buffalo framework using TOML fixtures. However, I am having trouble finding a clear example or documentation on how to do this.

Answer 1

To seed a database, you can use grifts. When creating a new application, there should be a dummy placeholder grift generated at grifts/db.go that looks like:

package grifts

import "github.com/gobuffalo/grift/grift"

var _ = grift.Namespace("db", func() {

    grift.Desc("seed", "Seeds a database")
    grift.Add("seed", func(c *grift.Context) error {
        // Add DB seeding stuff here
        return nil
    })

})

I attempted to use model.LoadFixture("seed widgets") in a grift, but there is some panic because it is not in a test environment. I think DB seeding from toml fixtures is not supported directly but that would be a useful feature. However looking at the code from LoadFixture, we can construct our own fixture loading:

Assuming you have a fixture with a scenario named name = "seed widgets":

package grifts

import (
    "fmt"
    "os"
    "strings"

    "github.com/gobuffalo/grift/grift"
    "github.com/gobuffalo/suite/v4"
    "github.com/gobuffalo/suite/v4/fix"
)

var _ = grift.Namespace("db", func() {

    grift.Desc("seed", "Seeds a database")
    grift.Add("seed", func(c *grift.Context) error {
        // The DB connection will connect to the environment set in `GO_ENV` (defaults to `test`)
        // Set this environment variable in your `.env` file to `development`

        // NOTE: it may be better to put seed fixtures in a different directory
        //       to seperate concerns
        model, err := suite.NewModelWithFixtures(os.DirFS("./fixtures"))
        if err != nil {
            return err
        }

        sc, err := fix.Find("seed widgets")
        if err != nil {
            return err
        }

        for _, table := range sc.Tables {
            for _, row := range table.Row {
                q := "insert into " + table.Name
                keys := []string{}
                skeys := []string{}
                for k := range row {
                    keys = append(keys, k)
                    skeys = append(skeys, ":"+k)
                }

                q = q + fmt.Sprintf(" (%s) values (%s)", strings.Join(keys, ","), strings.Join(skeys, ","))
                if _, err = model.DB.Store.NamedExec(q, row); err != nil {
                    return err
                }
            }
        }

        return nil
    })

})