github.com/Redstoneguy129/cli@v0.0.0-20230211220159-15dca4e91917/internal/db/branch/switch_/switch_.go (about)

     1  package switch_
     2  
     3  import (
     4  	"context"
     5  	"errors"
     6  	"fmt"
     7  	"os"
     8  	"path/filepath"
     9  
    10  	"github.com/jackc/pgx/v4"
    11  	"github.com/spf13/afero"
    12  	"github.com/Redstoneguy129/cli/internal/db/reset"
    13  	"github.com/Redstoneguy129/cli/internal/utils"
    14  )
    15  
    16  func Run(ctx context.Context, target string, fsys afero.Fs, options ...func(*pgx.ConnConfig)) error {
    17  	// 1. Sanity checks
    18  	{
    19  		if err := utils.LoadConfigFS(fsys); err != nil {
    20  			return err
    21  		}
    22  		if err := utils.AssertSupabaseDbIsRunning(); err != nil {
    23  			return err
    24  		}
    25  		if target != "main" && utils.IsBranchNameReserved(target) {
    26  			return errors.New("Cannot switch branch " + utils.Aqua(target) + ": branch name is reserved.")
    27  		}
    28  		branchPath := filepath.Join(filepath.Dir(utils.CurrBranchPath), target)
    29  		if _, err := fsys.Stat(branchPath); errors.Is(err, os.ErrNotExist) {
    30  			return errors.New("Branch " + utils.Aqua(target) + " does not exist.")
    31  		} else if err != nil {
    32  			return err
    33  		}
    34  	}
    35  
    36  	// 2. Check current branch
    37  	currBranch, err := utils.GetCurrentBranchFS(fsys)
    38  	if err != nil {
    39  		// Assume we are on main branch
    40  		currBranch = "main"
    41  	}
    42  
    43  	// 3. Switch Postgres database
    44  	if currBranch == target {
    45  		fmt.Println("Already on branch " + utils.Aqua(target) + ".")
    46  	} else if err := switchDatabase(ctx, currBranch, target, options...); err != nil {
    47  		return errors.New("Error switching to branch " + utils.Aqua(target) + ": " + err.Error())
    48  	} else {
    49  		fmt.Println("Switched to branch " + utils.Aqua(target) + ".")
    50  	}
    51  
    52  	// 4. Update current branch
    53  	if err := afero.WriteFile(fsys, utils.CurrBranchPath, []byte(target), 0644); err != nil {
    54  		return errors.New("Unable to update local branch file. Fix by running: echo '" + target + "' > " + utils.CurrBranchPath)
    55  	}
    56  	return nil
    57  }
    58  
    59  func switchDatabase(ctx context.Context, source, target string, options ...func(*pgx.ConnConfig)) error {
    60  	conn, err := utils.ConnectLocalPostgres(ctx, utils.Config.Hostname, utils.Config.Db.Port, "template1", options...)
    61  	if err != nil {
    62  		return err
    63  	}
    64  	defer conn.Close(context.Background())
    65  	if err := reset.DisconnectClients(ctx, conn); err != nil {
    66  		return err
    67  	}
    68  	defer reset.RestartDatabase(context.Background())
    69  	backup := "ALTER DATABASE postgres RENAME TO " + source + ";"
    70  	if _, err := conn.Exec(ctx, backup); err != nil {
    71  		return err
    72  	}
    73  	rename := "ALTER DATABASE " + target + " RENAME TO postgres;"
    74  	if _, err := conn.Exec(ctx, rename); err != nil {
    75  		rollback := "ALTER DATABASE " + source + " RENAME TO postgres;"
    76  		if _, err := conn.Exec(ctx, rollback); err != nil {
    77  			fmt.Fprintln(os.Stderr, "Failed to rollback database:", err)
    78  		}
    79  		return err
    80  	}
    81  	return nil
    82  }