fix connection string expansion, css

Dockerfile

@@ -9,6 +9,7 @@ FROM golang:1.17 AS build-go
 COPY . /src
 
 COPY --from=build-ui /src/ui/public/js/app.js /src/ui/public/js/app.js
+COPY --from=build-ui /src/ui/public/js/app.css /src/ui/public/js/app.css
 RUN cd /src/ && go build -x -ldflags "-linkmode external -extldflags -static"
 
 FROM alpine:3

api/data_connections.go

@@ -20,5 +20,6 @@ func (api *API) ReadDataConnection(id string) (*config.DataConnection, error) {
 	if err != nil {
 		return nil, err
 	}
+	conn.ExpandConnectionString()
 	return conn, nil
 }

config/config.go

@@ -41,7 +41,7 @@ type DataSource struct {
 	Query          string `yaml:"query" json:"query"`
 }
 
-func (dc *DataConnection) expandConnectionString() {
+func (dc *DataConnection) ExpandConnectionString() {
 	if strings.HasPrefix(dc.ConnectionString, "$") {
 		dc.ConnectionString = os.ExpandEnv(dc.ConnectionString)
 	}
@@ -92,7 +92,7 @@ func (c *Config) Parse(content []byte, dir string) error {
 	}
 
 	for i, dataConnection := range c.DataConnections {
-		dataConnection.expandConnectionString()
+		dataConnection.ExpandConnectionString()
 		if dataConnection.Path != "" {
 			if !filepath.IsAbs(dataConnection.Path) {
 				c.DataConnections[i].Path = filepath.Join(dir, dataConnection.Path)