Add full support for Steam Trading

jsont/jsont.go

@@ -0,0 +1,19 @@
+// Includes helper types for working with JSON data
+package jsont
+
+import (
+	"encoding/json"
+)
+
+// A boolean value that can be unmarshaled from a number in JSON.
+type UintBool bool
+
+func (u *UintBool) UnmarshalJSON(data []byte) error {
+	var n uint
+	err := json.Unmarshal(data, &n)
+	if err != nil {
+		return err
+	}
+	*u = n != 0
+	return nil
+}

trade/actions.go

@@ -0,0 +1,115 @@
+package trade
+
+import (
+	"errors"
+	"github.com/Philipp15b/go-steam/trade/inventory"
+	"github.com/Philipp15b/go-steam/trade/tradeapi"
+	"time"
+)
+
+type Slot uint
+
+func (t *Trade) action(status *tradeapi.Status, err error) error {
+	if err != nil {
+		return err
+	}
+	t.onStatus(status)
+	return nil
+}
+
+// Returns the next batch of events to process. These can be queued from calls to methods
+// like `AddItem` or, if there are no queued events, from a new HTTP request to Steam's API (blocking!).
+// If the latter is the case, this method may also sleep before the request
+// to conform to the polling interval of the official Steam client.
+func (t *Trade) Poll() ([]interface{}, error) {
+	if t.queuedEvents != nil {
+		return t.Events(), nil
+	}
+
+	if d := time.Since(t.lastPoll); d < pollTimeout {
+		time.Sleep(pollTimeout - d)
+	}
+	t.lastPoll = time.Now()
+
+	err := t.action(t.api.GetStatus())
+	if err != nil {
+		return nil, err
+	}
+
+	return t.Events(), nil
+}
+
+func (t *Trade) getFullInventory(getFirst func() (*inventory.PartialInventory, error), getNext func(start uint) (*inventory.PartialInventory, error)) (*inventory.Inventory, error) {
+	first, err := getFirst()
+	if err != nil {
+		return nil, err
+	}
+	if !first.Success {
+		return nil, errors.New("getFullInventory API call failed.")
+	}
+
+	result := &first.Inventory
+	var next *inventory.PartialInventory
+	for latest := first; latest.More; latest = next {
+		next, err := getNext(uint(latest.MoreStart))
+		if err != nil {
+			return nil, err
+		}
+		if !next.Success {
+			return nil, errors.New("getFullInventory API call failed.")
+		}
+
+		result = inventory.Merge(result, &next.Inventory)
+	}
+
+	return result, nil
+}
+
+func (t *Trade) GetTheirInventory(contextId uint64, appId uint32) (*inventory.Inventory, error) {
+	return t.getFullInventory(func() (*inventory.PartialInventory, error) {
+		return t.api.GetForeignInventory(contextId, appId, nil)
+	}, func(start uint) (*inventory.PartialInventory, error) {
+		return t.api.GetForeignInventory(contextId, appId, &start)
+	})
+}
+
+func (t *Trade) GetOwnInventory(contextId uint64, appId uint32) (*inventory.Inventory, error) {
+	return t.getFullInventory(func() (*inventory.PartialInventory, error) {
+		return t.api.GetOwnInventory(contextId, appId, nil)
+	}, func(start uint) (*inventory.PartialInventory, error) {
+		return t.api.GetOwnInventory(contextId, appId, &start)
+	})
+}
+
+func (t *Trade) GetMain() (*tradeapi.Main, error) {
+	return t.api.GetMain()
+}
+
+func (t *Trade) AddItem(slot Slot, item *Item) error {
+	return t.action(t.api.AddItem(uint(slot), item.AssetId, item.ContextId, item.AppId))
+}
+
+func (t *Trade) RemoveItem(slot Slot, item *Item) error {
+	return t.action(t.api.RemoveItem(uint(slot), item.AssetId, item.ContextId, item.AppId))
+}
+
+func (t *Trade) Chat(message string) error {
+	return t.action(t.api.Chat(message))
+}
+
+func (t *Trade) SetCurrency(amount uint, currency *Currency) error {
+	return t.action(t.api.SetCurrency(amount, currency.CurrencyId, currency.ContextId, currency.AppId))
+}
+
+func (t *Trade) SetReady(ready bool) error {
+	return t.action(t.api.SetReady(ready))
+}
+
+// This may only be called after a successful `SetReady(true)`.
+func (t *Trade) Confirm() error {
+	return t.action(t.api.Confirm())
+}
+
+func (t *Trade) Cancel() error {
+	return t.action(t.api.Cancel())
+}

trade/doc.go

@@ -0,0 +1,40 @@
+/*
+Allows automation of Steam Trading.
+
+Usage
+
+Like go-steam, this package is event-based. Call Poll() until the trade has ended, that is until the TradeEndedEvent is emitted.
+
+	// After receiving the steam.TradeSessionStartEvent
+	t := trade.New(sessionIdCookie, steamLoginCookie, event.Other)
+	for {
+		eventList, err := t.Poll()
+		if err != nil {
+			// error handling here
+			continue
+		}
+		for _, event := range eventList {
+			switch e := event.(type) {
+				case *trade.ChatEvent:
+					// respond to any chat message
+					t.Chat("Trading is awesome!")
+				case *trade.TradeEndedEvent:
+					return
+				// other event handlers here
+			}
+		}
+	}
+
+You can either log into steamcommunity.com and use the values of the `sessionId` and `steamLogin` cookies,
+or use go-steam and after logging in with client.Web.LogOn() and receiving the WebLoggedOnEvent use the `SessionId`
+and `SteamLogin` fields of steam.Web for the respective cookies.
+
+It is important that there is no delay between the Poll() calls greater than the timeout of the Steam client
+(currently five seconds before the trade partner sees a warning) or the trade will be closed automatically by Steam.
+
+Notes
+
+All method calls to Steam APIs are blocking. This packages' and its subpackages' types are not thread-safe and no calls to any method of the same
+trade instance may be done concurrently except when otherwise noted.
+*/
+package trade

trade/inventory/inventory.go

@@ -0,0 +1,110 @@
+package inventory
+
+import (
+	"bytes"
+	"encoding/json"
+	"github.com/Philipp15b/go-steam/jsont"
+)
+
+type Inventory struct {
+	Items        Items        `json:"rgInventory"`
+	Currencies   Currencies   `json:"rgCurrency"`
+	Descriptions Descriptions `json:"rgDescriptions"`
+	AppInfo      *AppInfo     `json:"rgAppInfo"`
+}
+
+type Items map[string]*Item
+
+func (i *Items) UnmarshalJSON(data []byte) error {
+	if bytes.Equal(data, []byte("[]")) {
+		return nil
+	}
+	return json.Unmarshal(data, (*map[string]*Item)(i))
+}
+
+type Currencies map[string]*Currency
+
+func (c *Currencies) UnmarshalJSON(data []byte) error {
+	if bytes.Equal(data, []byte("[]")) {
+		return nil
+	}
+	return json.Unmarshal(data, (*map[string]*Currency)(c))
+}
+
+type Descriptions map[string]*Description
+
+func (d *Descriptions) UnmarshalJSON(data []byte) error {
+	if bytes.Equal(data, []byte("[]")) {
+		return nil
+	}
+	return json.Unmarshal(data, (*map[string]*Description)(d))
+}
+
+type Item struct {
+	Id         uint64 `json:",string"`
+	ClassId    uint64 `json:",string"`
+	InstanceId uint64 `json:",string"`
+	Amount     uint64 `json:",string"`
+	Pos        uint32
+}
+
+type Currency struct {
+	Id         uint64 `json:",string"`
+	ClassId    uint64 `json:",string"`
+	IsCurrency bool   `json:"is_currency"`
+	Pos        uint32
+}
+
+type Description struct {
+	AppId      uint32 `json:",string"`
+	ClassId    uint64 `json:",string"`
+	InstanceId uint64 `json:",string"`
+
+	IconUrl     string `json:"icon_url"`
+	IconDragUrl string `json:"icon_drag_url"`
+
+	Name       string
+	MarketName string `json:"market_name"`
+
+	// Colors in hex, for example `B2B2B2`
+	NameColor       string `json:"name_color"`
+	BackgroundColor string `json:"background_color"`
+
+	Type string
+
+	Tradable   jsont.UintBool
+	Marketable jsont.UintBool
+	Commodity  jsont.UintBool
+
+	Descriptions DescriptionLines
+	Actions      []*Action
+	// Application-specific data, like "def_index" and "quality" for TF2
+	AppData map[string]string
+}
+
+type DescriptionLines []*DescriptionLine
+
+func (d *DescriptionLines) UnmarshalJSON(data []byte) error {
+	if bytes.Equal(data, []byte(`""`)) {
+		return nil
+	}
+	return json.Unmarshal(data, (*[]*DescriptionLine)(d))
+}
+
+type DescriptionLine struct {
+	Value string
+	Type  *string // Is `html` for HTML descriptions
+	Label *string
+}
+
+type Action struct {
+	Name string
+	Link string
+}
+
+type AppInfo struct {
+	AppId uint32
+	Name  string
+	Icon  string
+	Link  string
+}

trade/inventory/partial.go

@@ -0,0 +1,47 @@
+package inventory
+
+import (
+	"bytes"
+	"encoding/json"
+)
+
+// A partial inventory as sent by the Steam API.
+type PartialInventory struct {
+	Success bool
+	Inventory
+	More      bool
+	MoreStart MoreStart `json:"more_start"`
+}
+
+type MoreStart uint
+
+func (m *MoreStart) UnmarshalJSON(data []byte) error {
+	if bytes.Equal(data, []byte("false")) {
+		return nil
+	}
+	return json.Unmarshal(data, (*uint)(m))
+}
+
+// Merges the given Inventory into a single Inventory.
+// The given slice must have at least one element. The first element of the slice is used
+// and modified.
+func Merge(p ...*Inventory) *Inventory {
+	inv := p[0]
+	for idx, i := range p {
+		if idx == 0 {
+			continue
+		}
+
+		for key, value := range i.Items {
+			inv.Items[key] = value
+		}
+		for key, value := range i.Descriptions {
+			inv.Descriptions[key] = value
+		}
+		for key, value := range i.Currencies {
+			inv.Currencies[key] = value
+		}
+	}
+
+	return inv
+}