From 88147fe50e7e0e1f7d6e5e742ca6832874dc388c Mon Sep 17 00:00:00 2001
From: ekzyis <ekzyis@ekzyis.com>
Date: Fri, 7 Apr 2023 08:56:18 +0200
Subject: [PATCH] First successful SN post

https://stacker.news/items/161801
---
 .env.template |   1 +
 .gitignore    |   1 +
 README.md     |   7 +++
 go.mod        |   8 +++
 go.sum        |   4 ++
 main.go       | 150 ++++++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 171 insertions(+)
 create mode 100644 .env.template
 create mode 100644 .gitignore
 create mode 100644 README.md
 create mode 100644 go.mod
 create mode 100644 go.sum
 create mode 100644 main.go

diff --git a/.env.template b/.env.template
new file mode 100644
index 0000000..959dded
--- /dev/null
+++ b/.env.template
@@ -0,0 +1 @@
+AUTH_COOKIE=
\ No newline at end of file
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..2eea525
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.env
\ No newline at end of file
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..0cd9338
--- /dev/null
+++ b/README.md
@@ -0,0 +1,7 @@
+# hnbot
+
+> Hello, I am a bot crossposting top posts from HN.
+>
+> I curate content to only post stuff which could be interesting for the SN community on a best-efforts basis.
+
+-- https://stacker.news/items/161788
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..b2158ce
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,8 @@
+module gitlab.com/ekzyis/hnbot
+
+go 1.20
+
+require (
+	github.com/joho/godotenv v1.5.1 // indirect
+	github.com/namsral/flag v1.7.4-pre // indirect
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..4c16f8b
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,4 @@
+github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
+github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
+github.com/namsral/flag v1.7.4-pre h1:b2ScHhoCUkbsq0d2C15Mv+VU8bl8hAXV8arnWiOHNZs=
+github.com/namsral/flag v1.7.4-pre/go.mod h1:OXldTctbM6SWH1K899kPZcf65KxJiD7MsceFUpB5yDo=
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..ebb3707
--- /dev/null
+++ b/main.go
@@ -0,0 +1,150 @@
+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+
+	"github.com/joho/godotenv"
+	"github.com/namsral/flag"
+)
+
+var (
+	AuthCookie string
+)
+
+func init() {
+	err := godotenv.Load()
+	if err != nil {
+		log.Fatal("Error loading .env file")
+	}
+	flag.StringVar(&AuthCookie, "auth_cookie", "", "Cookie required for authorization")
+	flag.Parse()
+	if AuthCookie == "" {
+		log.Fatal("auth cookie not set")
+	}
+}
+
+type ItemID = int
+
+type Story struct {
+	ID          ItemID
+	By          string // username of author
+	Time        int    // UNIX timestamp
+	Descendants int    // number of comments
+	Kids        []ItemID
+	Score       int
+	Title       string
+	Url         string
+}
+
+type GraphQLPayload struct {
+	Query     string                 `json:"query"`
+	Variables map[string]interface{} `json:"variables,omitempty"`
+}
+
+func fetchTopStoriesFromHN() []Story {
+	// API docs: https://github.com/HackerNews/API
+
+	url := "https://hacker-news.firebaseio.com/v0/topstories.json"
+	resp, err := http.Get(url)
+	if err != nil {
+		log.Fatal("Error fetching top stories:", err)
+	}
+	defer resp.Body.Close()
+	log.Printf("GET %s %d\n", url, resp.StatusCode)
+
+	var ids []int
+	err = json.NewDecoder(resp.Body).Decode(&ids)
+	if err != nil {
+		log.Fatal("Error decoding top stories JSON:", err)
+	}
+
+	// we are only interested in the first page of top stories
+	const limit = 30
+	ids = ids[:limit]
+
+	var stories [limit]Story
+	for i, id := range ids {
+		story := fetchStoryByID(id)
+		stories[i] = story
+	}
+
+	// Can't return [30]Story as []Story so we copy the array
+	return stories[:]
+}
+
+func fetchStoryByID(id ItemID) Story {
+	url := fmt.Sprintf("https://hacker-news.firebaseio.com/v0/item/%d.json", id)
+	resp, err := http.Get(url)
+	if err != nil {
+		log.Fatal("Error fetching story:", err)
+	}
+	defer resp.Body.Close()
+	log.Printf("GET %s %d\n", url, resp.StatusCode)
+
+	var story Story
+	err = json.NewDecoder(resp.Body).Decode(&story)
+	if err != nil {
+		log.Fatal("Error decoding story JSON:", err)
+	}
+
+	return story
+}
+
+func filterByRelevanceForSN(stories *[]Story) *[]Story {
+	// TODO: filter by relevance
+
+	slice := (*stories)[0:1]
+	return &slice
+}
+
+func postToSN(story *Story) {
+	// TODO: check for dupes first
+
+	body := GraphQLPayload{
+		Query: `
+            mutation upsertLink($url: String!, $title: String!) {
+                upsertLink(url: $url, title: $title) {
+                    id
+                }
+            }
+        `,
+		Variables: map[string]interface{}{
+			"url":   story.Url,
+			"title": story.Title,
+		},
+	}
+
+	bodyJSON, err := json.Marshal(body)
+	if err != nil {
+		log.Fatal("Error during json.Marshal:", err)
+	}
+
+	url := "https://stacker.news/api/graphql"
+	req, err := http.NewRequest("POST", url, bytes.NewBuffer(bodyJSON))
+	if err != nil {
+		panic(err)
+	}
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Cookie", AuthCookie)
+
+	client := http.DefaultClient
+	resp, err := client.Do(req)
+	if err != nil {
+		panic(err)
+	}
+	defer resp.Body.Close()
+
+	log.Printf("POST %s %d\n", url, resp.StatusCode)
+}
+
+func main() {
+	stories := fetchTopStoriesFromHN()
+	filtered := filterByRelevanceForSN(&stories)
+	for _, story := range *filtered {
+		postToSN(&story)
+	}
+}