Local queries (#641)

* Read local queries from pgweb home directory
* Refactor local query functionality
* Allow picking local query in the query tab
* WIP
* Disable local query dropdown during execution
* Only allow local queries running in a single session mode
* Add middleware to enforce local query endpoint availability
* Fix query check
* Add query store tests
* Make query store errors portable
* Skip building specific tests on windows

pkg/client/client.go

@@ -585,3 +585,44 @@ func (client *Client) hasHistoryRecord(query string) bool {
 
 	return result
 }
+
+type ConnContext struct {
+	Host     string
+	User     string
+	Database string
+	Mode     string
+}
+
+func (c ConnContext) String() string {
+	return fmt.Sprintf(
+		"host=%q user=%q database=%q mode=%q",
+		c.Host, c.User, c.Database, c.Mode,
+	)
+}
+
+// ConnContext returns information about current database connection
+func (client *Client) GetConnContext() (*ConnContext, error) {
+	url, err := neturl.Parse(client.ConnectionString)
+	if err != nil {
+		return nil, err
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*10)
+	defer cancel()
+
+	connCtx := ConnContext{
+		Host: url.Hostname(),
+		Mode: "default",
+	}
+
+	if command.Opts.ReadOnly {
+		connCtx.Mode = "readonly"
+	}
+
+	row := client.db.QueryRowContext(ctx, "SELECT current_user, current_database()")
+	if err := row.Scan(&connCtx.User, &connCtx.Database); err != nil {
+		return nil, err
+	}
+
+	return &connCtx, nil
+}

pkg/client/client_test.go

@@ -660,6 +660,15 @@ func testTablesStats(t *testing.T) {
 	assert.Equal(t, columns, result.Columns)
 }
 
+func testConnContext(t *testing.T) {
+	result, err := testClient.GetConnContext()
+	assert.NoError(t, err)
+	assert.Equal(t, "localhost", result.Host)
+	assert.Equal(t, "postgres", result.User)
+	assert.Equal(t, "booktown", result.Database)
+	assert.Equal(t, "default", result.Mode)
+}
+
 func TestAll(t *testing.T) {
 	if onWindows() {
 		t.Log("Unit testing on Windows platform is not supported.")
@@ -698,6 +707,7 @@ func TestAll(t *testing.T) {
 	testReadOnlyMode(t)
 	testDumpExport(t)
 	testTablesStats(t)
+	testConnContext(t)
 
 	teardownClient()
 	teardown(t, true)