Initial commitv0.1.0

7 files changed, 216 insertions, 0 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
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+++ b/CHANGELOG.md
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+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [0.1.0] - 2024-11-29
+
+Initial release
diff --git a/README.md b/README.md
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+++ b/README.md
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+# transmission
+
+A Go-native library for communicating with the [Transmission RPC
+interface](https://github.com/transmission/transmission/blob/main/docs/rpc-spec.md).
diff --git a/api.go b/api.go
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+++ b/api.go
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+package transmission
+
+var TorrentStatus = map[int]string{
+	0: "stopped",
+	1: "verify-pending",
+	2: "verifying",
+	3: "download-pending",
+	4: "downloading",
+	5: "seed-pending",
+	6: "seeding",
+}
+
+type Torrent struct {
+	Status     int    `json:"status"`
+	Id         int    `json:"id"`
+	Name       string `json:"name"`
+	HashString string `json:"hashString"`
+}
+
+type StatsObject struct {
+	UploadedBytes   uint `json:"uploadedBytes"`
+	DownloadedBytes uint `json:"downloadedBytes"`
+	FilesAdded      uint `json:"filesAdded"`
+	SessionCount    uint `json:"sessionCount"`
+	SecondsActive   uint `json:"secondsActive"`
+}
diff --git a/api_session_stats.go b/api_session_stats.go
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+++ b/api_session_stats.go
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+package transmission
+
+type CallSessionStatsResponse struct {
+	Result    string                            `json:"result"`
+	Arguments CallSessionStatsResponseArguments `json:"arguments"`
+	Tag       uint                              `json:"tag"`
+}
+
+type CallSessionStatsResponseArguments struct {
+	ActiveTorrentCount uint        `json:"activeTorrentCount"`
+	DownloadSpeed      uint        `json:"downloadSpeed"`
+	PausedTorrentCount uint        `json:"pausedTorrentCount"`
+	TorrentCount       uint        `json:"torrentCount"`
+	UploadSpeed        uint        `json:"uploadSpeed"`
+	CumulativeStats    StatsObject `json:"cumulative-stats"`
+	CurrentStats       StatsObject `json:"current-stats"`
+}
+
+func (this *Client) CallSessionStats() (CallSessionStatsResponse, error) {
+	var response CallSessionStatsResponse
+
+	err := this.Call("session-stats", nil, this.makeTag(), &response)
+
+	return response, err
+}
diff --git a/api_torrent_get.go b/api_torrent_get.go
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index 0000000..7c4859a
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+++ b/api_torrent_get.go
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+package transmission
+
+type CallTorrentGetArguments struct {
+	Ids    []uint   `json:"ids"`
+	Fields []string `json:"fields"`
+}
+
+type CallTorrentGetAllArguments struct {
+	Fields []string `json:"fields"`
+}
+
+type CallTorrentGetResponse struct {
+	Result    string                          `json:"result"`
+	Arguments CallTorrentGetResponseArguments `json:"arguments"`
+	Tag       uint                            `json:"tag"`
+}
+
+type CallTorrentGetResponseArguments struct {
+	Torrents []Torrent `json:"torrents"`
+}
+
+func (this *Client) CallTorrentGet(arguments CallTorrentGetArguments) (CallTorrentGetResponse, error) {
+	var response CallTorrentGetResponse
+
+	err := this.Call("torrent-get", arguments, this.makeTag(), &response)
+
+	return response, err
+}
+
+func (this *Client) CallTorrentGetAll(arguments CallTorrentGetAllArguments) (CallTorrentGetResponse, error) {
+	var response CallTorrentGetResponse
+
+	err := this.Call("torrent-get", arguments, this.makeTag(), &response)
+
+	return response, err
+}
diff --git a/client.go b/client.go
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index 0000000..d8303ab
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+++ b/client.go
@@ -0,0 +1,112 @@
+// The transmission package provides a Go-native interface for communicating
+// with the Transmission RPC interface.
+package transmission
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+	"log/slog"
+	"math/rand"
+	"net/http"
+	"strconv"
+)
+
+type CallArguments interface {
+	CallTorrentGetArguments | interface{}
+}
+
+// The base struct for a Transmission client to perform RPC calls with.
+type Client struct {
+	Hostname string
+	Port     int
+	Username string
+	Password string
+
+	httpClient http.Client
+	sessionId  string
+}
+
+// Call a given method on the Transmission RPC interface, and pass it the given arguments in JSON.
+func (this *Client) Call(method string, arguments CallArguments, tag uint, response interface{}) error {
+	// Create HTTP client to work with
+	httpClient := http.Client{}
+
+	// Create the Request object
+	req, _ := this.makeRequest(method, arguments, tag)
+
+	slog.Debug("Sending request", "address", req.URL.String(), "session-id", this.sessionId, "tag", tag)
+	res, err := httpClient.Do(req)
+	if err != nil {
+		return err
+	}
+
+	// Read the response
+	body, err := io.ReadAll(res.Body)
+	if err != nil {
+		return err
+	}
+	defer res.Body.Close()
+
+	slog.Debug("Got response", "status", res.StatusCode, "body", body, "tag", tag)
+
+	// Check if we're missing the session-id
+	if res.StatusCode == 409 {
+		slog.Debug("Got new session-id", "tag", tag)
+		this.sessionId = res.Header["X-Transmission-Session-Id"][0]
+		return this.Call(method, arguments, tag, response)
+	}
+
+	// Unmarshal it into the response
+	json.Unmarshal(body, &response)
+
+	// Return the response
+	return nil
+}
+
+// Convenience function to generate the URL to post RPC calls to.
+func (this *Client) connectionString() string {
+	url := "http://" + this.Hostname
+
+	if this.Port != 0 {
+		url += ":" + strconv.Itoa(this.Port)
+	} else {
+		url += ":9091"
+	}
+
+	url += "/transmission/rpc"
+
+	return url
+}
+
+// makeRequest provides a convenience function to make a new http.Request
+// object. It sets the URL, headers, and body of the request.
+func (this *Client) makeRequest(method string, arguments CallArguments, tag uint) (*http.Request, error) {
+	body, _ := json.Marshal(map[string]interface{}{
+		"method":    method,
+		"arguments": arguments,
+		"tag":       tag,
+	})
+
+	slog.Debug("Making request", "body", body, "tag", tag)
+
+	req, err := http.NewRequest("POST", this.connectionString(), bytes.NewBuffer([]byte(body)))
+	if err != nil {
+		return nil, err
+	}
+
+	if this.Username != "" {
+		slog.Debug("Adding Authorization header", "tag", tag)
+		req.SetBasicAuth(this.Username, this.Password)
+	}
+
+	req.Header.Add("X-Transmission-Session-Id", this.sessionId)
+
+	return req, nil
+}
+
+// Generate a tag ID. Since the maximum value is not documented, this allows
+// for easy bug-fixing later in life.
+func (this *Client) makeTag() uint {
+	return uint(rand.Uint32())
+}
diff --git a/go.mod b/go.mod
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index 0000000..c3ddf92
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+++ b/go.mod
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+module git.tyil.nl/go/transmission.git
+
+go 1.23.2