Problems with exporter script

Archive Python API
1

hey guys,
right now I write a script to send the meshdata of my objects over tcp to another program. It works quite good but there are a few problems.

first I want to ask you if there is a better way to get all the mesh-data. right now I do it that way:

def getMeshData(self,obj):
        temp = {}
        vertices = []
        normals = []
        indices = []
    
        if obj.data.is_editmode:
            bm = bmesh.from_edit_mesh(obj.data)
        else:
            bm = bmesh.new()
            bm.from_mesh(obj.data)
    
        bmesh.ops.split_edges(bm,edges=bm.edges, verts=bm.verts)
        bmesh.ops.triangulate(bm,faces=bm.faces)
    
        for vert in bm.verts:
            vertices.append(vert.co[0])
            vertices.append(vert.co[2])
            vertices.append(vert.co[1])
            normals.append(vert.normal[0])
            normals.append(vert.normal[2])
            normals.append(vert.normal[1])
        for face in bm.faces:
            for vert in face.verts:
                indices.append(vert.index)
        temp = {'vertices':vertices, 'normals':normals, 'indices':indices}

second: If I do it this way and tab into edit mode and back to object mode my object gets splitted edges and triangulated. but I thought If I use bmesh the original objects doesnt get changed. what do I get wrong here?

thank you for your help in advance
cheers