Need API specifations for Sending File

Hi friends,
I am very new to this mattermost environment, and I really need the API specifications for sending files. What are the parameters required and what are those header details for uploading/sending file, and what are those other APIs triggered/associated with the API for sending files “http://xxxx:8065/api/v1/files/upload”? Currently I am developing an android app that will integrate those mattermost APIs. So I need some guidelines and I shall be vary happy thankful if somebody helps me.

May this helps you. The below is the structure for post event.

type Post struct {
Id string json:"id"
CreateAt int64 json:"create_at"
UpdateAt int64 json:"update_at"
DeleteAt int64 json:"delete_at"
UserId string json:"user_id"
ChannelId string json:"channel_id"
RootId string json:"root_id"
ParentId string json:"parent_id"
OriginalId string json:"original_id"
Message string json:"message"
Type string json:"type"
Props StringInterface json:"props"
Hashtags string json:"hashtags"
Filenames StringArray json:"filenames"
PendingPostId string json:"pending_post_id" db:"-"