Add atlas migrate diff

atlasexec/atlas.go

@@ -24,6 +24,21 @@ type (
 	LoginParams struct {
 		Token string
 	}
+	// MigrateDiffParams are the parameters for the `migrate diff` command.
+	MigrateDiffParams struct {
+		ToURL          string
+		DevURL         string
+		DirURL         string
+		DirFormat      string
+		Schema         string
+		LockTimeout    string
+		Format         string
+		Qualifier      string
+		Context        *RunContext
+		ConfigURL      string
+		Env            string
+		Vars           Vars
+	}
 	// MigratePushParams are the parameters for the `migrate push` command.
 	MigratePushParams struct {
 		Name        string
@@ -248,6 +263,48 @@ func (c *Client) MigratePush(ctx context.Context, params *MigratePushParams) (st
 	return strings.TrimSpace(resp), err
 }
 
+// MigrateDiff runs the 'migrate diff' command.
+func (c *Client) MigrateDiff(ctx context.Context, params *MigrateDiffParams) (string, error) {
+	args := []string{"migrate", "diff", "--format", "{{ sql }}"}
+	if params.ToURL != "" {
+		args = append(args, "--to", params.ToURL)
+	}
+	if params.DevURL != "" {
+		args = append(args, "--dev-url", params.DevURL)
+	}
+	if params.DirURL != "" {
+		args = append(args, "--dir", params.DirURL)
+	}
+	if params.DirFormat != "" {
+		args = append(args, "--dir-format", params.DirFormat)
+	}
+	if params.Schema != "" {
+		args = append(args, "--schema", params.Schema)
+	}
+	if params.LockTimeout != "" {
+		args = append(args, "--lock-timeout", params.LockTimeout)
+	}
+	if params.Qualifier != "" {
+		args = append(args, "--qualifier", params.Qualifier)
+	}
+	if params.Context != nil {
+		buf, err := json.Marshal(params.Context)
+		if err != nil {
+			return "", err
+		}
+		args = append(args, "--context", string(buf))
+	}
+	if params.ConfigURL != "" {
+		args = append(args, "--config", params.ConfigURL)
+	}
+	if params.Env != "" {
+		args = append(args, "--env", params.Env)
+	}
+	args = append(args, params.Vars.AsArgs()...)
+	resp, err := stringVal(c.runCommand(ctx, args))
+	return strings.TrimSpace(resp), err
+}
+
 // MigrateApply runs the 'migrate apply' command.
 func (c *Client) MigrateApply(ctx context.Context, params *MigrateApplyParams) (*MigrateApply, error) {
 	return firstResult(c.MigrateApplySlice(ctx, params))

atlasexec/atlas_test.go

@@ -460,6 +460,57 @@ func TestMigrateLintWithLogin(t *testing.T) {
 		require.True(t, found)
 	})
 }
+func TestMigrateDiff(t *testing.T) {
+	wd, err := os.Getwd()
+	require.NoError(t, err)
+	// Mock the client with a script that just prints the arguments to stderr and
+	// exit with an error code.
+	c, err := atlasexec.NewClient(t.TempDir(), filepath.Join(wd, "./mock-args.sh"))
+	require.NoError(t, err)
+
+	for _, tt := range []struct {
+		name   string
+		params *atlasexec.MigrateDiffParams
+		expect string
+	}{
+		{
+			name:   "no params",
+			params: &atlasexec.MigrateDiffParams{},
+			expect: "migrate diff --format {{ sql }}",
+		},
+		{
+			name: "with env",
+			params: &atlasexec.MigrateDiffParams{
+				Env: "test",
+			},
+			expect: "migrate diff --format {{ sql }} --env test",
+		},
+		{
+			name: "with url",
+			params: &atlasexec.MigrateDiffParams{
+				DevURL: "sqlite://file?_fk=1&cache=shared&mode=memory",
+			},
+			expect: "migrate diff --format {{ sql }} --dev-url sqlite://file?_fk=1&cache=shared&mode=memory",
+		},
+		{
+			name: "with exec order",
+			params: &atlasexec.MigrateDiffParams{
+				Env: "gorm",
+			},
+			expect: "migrate diff --format {{ sql }} --env gorm",
+		},
+	} {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := c.MigrateDiff(context.Background(), tt.params)
+			require.Error(t, err)
+			// The script mock-args.sh exit with an error code.
+			// So, our atlasexec.MigrateApply should return a cliError.
+			// Which contains all output from the script (both stdout and stderr).
+			require.Equal(t, tt.expect, err.Error())
+		})
+	}
+}
+
 
 func TestMigratePush(t *testing.T) {
 	type (