fix: show readable error messages when feed subscription fails

app/src/main/java/me/ash/reader/infrastructure/rss/RssHelper.kt

@@ -37,6 +37,12 @@ import org.jsoup.Jsoup
 val enclosureRegex = """<enclosure\s+url="([^"]+)"\s+type=".*"\s*/>""".toRegex()
 val imgRegex = """img.*?src=(["'])((?!data).*?)\1""".toRegex(RegexOption.DOT_MATCHES_ALL)
 
+/** Thrown when the requested feed URL answers with a non-successful HTTP status code. */
+class FeedHttpException(message: String, val statusCode: Int) : IOException(message)
+
+/** Thrown when the requested URL is not a feed and no feed could be discovered on the page. */
+class FeedNotFoundException(message: String) : IOException(message)
+
 /** Some operations on RSS. */
 class RssHelper
 @Inject
@@ -55,7 +61,12 @@ constructor(
     suspend fun searchFeed(feedLink: String): SearchFeedResult {
         return withContext(ioDispatcher) {
             val directResponse = response(okHttpClient, feedLink)
-            if (!directResponse.commonIsSuccessful) throw IOException(directResponse.message)
+            if (!directResponse.commonIsSuccessful) {
+                throw FeedHttpException(
+                    message = "HTTP ${directResponse.code} ${directResponse.message}",
+                    statusCode = directResponse.code,
+                )
+            }
             val directBody = directResponse.body.bytes()
             val directHttpContentType = toHttpContentType(directResponse.header("Content-Type"))
 
@@ -64,13 +75,16 @@ constructor(
             val resolvedFeedLink =
                 if (parsedDirectFeed != null) feedLink
                 else discoverFeedLink(feedLink, directBody)
-                    ?: throw IOException("Unable to detect RSS feed URL")
+                    ?: throw FeedNotFoundException("Unable to detect RSS feed URL")
 
 
             val feed = parsedDirectFeed ?: run {
                 val discoveredResponse = response(okHttpClient, resolvedFeedLink)
                 if (!discoveredResponse.commonIsSuccessful) {
-                    throw IOException(discoveredResponse.message)
+                    throw FeedHttpException(
+                        message = "HTTP ${discoveredResponse.code} ${discoveredResponse.message}",
+                        statusCode = discoveredResponse.code,
+                    )
                 }
                 parseFeed(
                     discoveredResponse.body.bytes(),

app/src/main/java/me/ash/reader/ui/page/home/feeds/subscribe/SubscribeErrors.kt

@@ -0,0 +1,52 @@
+package me.ash.reader.ui.page.home.feeds.subscribe
+
+import androidx.annotation.StringRes
+import com.rometools.rome.io.FeedException
+import java.net.ConnectException
+import java.net.NoRouteToHostException
+import java.net.SocketTimeoutException
+import java.net.UnknownHostException
+import javax.net.ssl.SSLException
+import me.ash.reader.R
+import me.ash.reader.infrastructure.rss.FeedHttpException
+import me.ash.reader.infrastructure.rss.FeedNotFoundException
+import org.xml.sax.SAXParseException
+
+/**
+ * Maps an exception raised while importing a feed through
+ * [me.ash.reader.infrastructure.rss.RssHelper.searchFeed] to a user-facing
+ * error message.
+ *
+ * Import failures fall into a few categories that the user can actually act on:
+ * - the host is unreachable or TLS is blocked (e.g. a status page that is
+ *   geo-blocked or behind an ICP firewall) -> [R.string.subscribe_error_network]
+ * - the server answered with an error status -> [R.string.subscribe_error_http]
+ * - the URL is not a feed and no feed could be discovered
+ *   -> [R.string.subscribe_error_feed_not_found]
+ * - the body could not be parsed as RSS/Atom -> [R.string.subscribe_error_parse]
+ *
+ * Anything else keeps its original message ([SubscribeError.Raw]) so that no
+ * debugging information is lost.
+ */
+fun Throwable.toSubscribeError(): SubscribeError =
+    when (this) {
+        is FeedHttpException -> SubscribeError.Text(R.string.subscribe_error_http, listOf(statusCode))
+        is FeedNotFoundException -> SubscribeError.Text(R.string.subscribe_error_feed_not_found)
+        is SSLException,
+        is UnknownHostException,
+        is ConnectException,
+        is SocketTimeoutException,
+        is NoRouteToHostException,
+        -> SubscribeError.Text(R.string.subscribe_error_network)
+        is SAXParseException, is FeedException,
+        -> SubscribeError.Text(R.string.subscribe_error_parse)
+        else -> SubscribeError.Raw(message.orEmpty())
+    }
+
+sealed interface SubscribeError {
+    /** A localized message referenced by a string resource. */
+    data class Text(@StringRes val resId: Int, val formatArgs: List<Any> = emptyList()) : SubscribeError
+
+    /** The raw exception message; falls back to [R.string.subscribe_error_fallback] when empty. */
+    data class Raw(val message: String) : SubscribeError
+}

app/src/main/java/me/ash/reader/ui/page/home/feeds/subscribe/SubscribeViewModel.kt

@@ -169,8 +169,24 @@ constructor(
                                     selectedGroupId = firstGroupId,
                                 )
                         }
-                        .onFailure {
-                            _subscribeState.value = currentState.copy(errorMessage = it.message)
+                        .onFailure { throwable ->
+                            val errorMessage =
+                                when (val error = throwable.toSubscribeError()) {
+                                    is SubscribeError.Text ->
+                                        androidStringsHelper.getString(
+                                            error.resId,
+                                            *error.formatArgs.toTypedArray(),
+                                        )
+
+                                    is SubscribeError.Raw ->
+                                        error.message.ifBlank {
+                                            androidStringsHelper.getString(
+                                                R.string.subscribe_error_fallback
+                                            )
+                                        }
+                                }
+                            _subscribeState.value =
+                                currentState.copy(errorMessage = errorMessage)
                         }
                 }
 

app/src/main/res/values-zh-rCN/strings.xml

@@ -32,6 +32,11 @@
     <string name="searching">搜索中…</string>
     <string name="subscribe">订阅</string>
     <string name="already_subscribed">已有订阅</string>
+    <string name="subscribe_error_network">无法连接到服务器，请检查网络连接，并确认该站点可以访问。</string>
+    <string name="subscribe_error_http">服务器拒绝了该订阅地址（HTTP %1$d）。</string>
+    <string name="subscribe_error_feed_not_found">在此地址未找到 RSS/Atom 订阅源。</string>
+    <string name="subscribe_error_parse">此地址看起来是订阅源，但内容无法解析。</string>
+    <string name="subscribe_error_fallback">添加订阅失败，请重试。</string>
     <string name="clear">清空</string>
     <string name="paste">粘贴</string>
     <string name="feed_or_site_url">订阅源或站点链接</string>

app/src/main/res/values/strings.xml

@@ -38,6 +38,11 @@
     <string name="searching">Searching…</string>
     <string name="subscribe">Subscribe</string>
     <string name="already_subscribed">Already subscribed</string>
+    <string name="subscribe_error_network">Couldn\'t connect to the server. Check your network connection and make sure this site is reachable.</string>
+    <string name="subscribe_error_http">The server rejected this feed URL (HTTP %1$d).</string>
+    <string name="subscribe_error_feed_not_found">No RSS/Atom feed was found at this URL.</string>
+    <string name="subscribe_error_parse">This URL looks like a feed, but its content could not be parsed.</string>
+    <string name="subscribe_error_fallback">Failed to add this feed. Please try again.</string>
     <string name="clear">Clear</string>
     <string name="paste">Paste</string>
     <string name="feed_or_site_url">Feed or site URL</string>

app/src/test/java/me/ash/reader/infrastructure/rss/StatuspageAtomParsingTest.kt

@@ -0,0 +1,71 @@
+package me.ash.reader.infrastructure.rss
+
+import com.rometools.rome.io.SyndFeedInput
+import com.rometools.rome.io.XmlReader
+import java.io.ByteArrayInputStream
+import java.io.File
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotNull
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+/**
+ * Verifies that ROME (the feed parser used by ReadYou) can parse an Atom feed
+ * in the exact shape served by Atlassian Statuspage instances
+ * (e.g. https://status.deepseek.com/feed.rss which redirects to /history.atom).
+ *
+ * The fixture is a real statuspage Atom payload captured from a live instance
+ * and truncated to the first 3 entries.
+ */
+class StatuspageAtomParsingTest {
+
+    private fun readSampleAtom(): ByteArray {
+        val resource =
+            requireNotNull(javaClass.classLoader?.getResourceAsStream("fixtures/statuspage_history.atom")) {
+                "fixture statuspage_history.atom not found on classpath"
+            }
+        return resource.use { it.readBytes() }
+    }
+
+    @Test
+    fun `statuspage atom feed parses with http content type like real server`() {
+        val body = readSampleAtom()
+        val feed =
+            SyndFeedInput().build(
+                XmlReader(
+                    ByteArrayInputStream(body),
+                    "application/atom+xml; charset=utf-8", // exact Content-Type of statuspage
+                )
+            )
+
+        assertNotNull(feed.title)
+        assertTrue("feed must expose entries", feed.entries.isNotEmpty())
+        assertEquals("first entry should carry an incident link", 3, feed.entries.size)
+
+        val first = feed.entries.first()
+        assertNotNull("entry title", first.title)
+        assertNotNull("entry link", first.link)
+        assertTrue(
+            "entry link should point to an incident page",
+            first.link!!.contains("/incidents/") || first.link!!.contains("/history"),
+        )
+    }
+
+    @Test
+    fun `statuspage atom entries expose published and updated dates`() {
+        val body = readSampleAtom()
+        val feed =
+            SyndFeedInput().build(
+                XmlReader(
+                    ByteArrayInputStream(body),
+                    "application/atom+xml; charset=utf-8",
+                )
+            )
+        feed.entries.forEach { entry ->
+            assertNotNull(
+                "entry '${entry.title}' must expose a usable date (published or updated)",
+                entry.publishedDate ?: entry.updatedDate,
+            )
+        }
+    }
+}

app/src/test/java/me/ash/reader/ui/page/home/feeds/subscribe/SubscribeErrorsTest.kt

@@ -0,0 +1,77 @@
+package me.ash.reader.ui.page.home.feeds.subscribe
+
+import com.rometools.rome.io.ParsingFeedException
+import java.io.IOException
+import java.net.ConnectException
+import java.net.NoRouteToHostException
+import java.net.SocketTimeoutException
+import java.net.UnknownHostException
+import javax.net.ssl.SSLHandshakeException
+import me.ash.reader.R
+import me.ash.reader.infrastructure.rss.FeedHttpException
+import me.ash.reader.infrastructure.rss.FeedNotFoundException
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import org.xml.sax.SAXParseException
+
+class SubscribeErrorsTest {
+
+    @Test
+    fun `http error maps to localized http message with status code`() {
+        val error = FeedHttpException("HTTP 403 Forbidden", 403).toSubscribeError()
+        assertEquals(SubscribeError.Text(R.string.subscribe_error_http, listOf(403)), error)
+    }
+
+    @Test
+    fun `unreachable host maps to network message`() {
+        val errors =
+            listOf(
+                SSLHandshakeException("connection closed"),
+                UnknownHostException("status.deepseek.com"),
+                ConnectException("refused"),
+                SocketTimeoutException("timeout"),
+                NoRouteToHostException("no route"),
+            )
+        errors.forEach {
+            assertEquals(
+                "expected network message for ${it::class.java.simpleName}",
+                SubscribeError.Text(R.string.subscribe_error_network),
+                it.toSubscribeError(),
+            )
+        }
+    }
+
+    @Test
+    fun `feed not found maps to dedicated message`() {
+        val error = FeedNotFoundException("Unable to detect RSS feed URL").toSubscribeError()
+        assertEquals(SubscribeError.Text(R.string.subscribe_error_feed_not_found), error)
+    }
+
+    @Test
+    fun `unparseable feed body maps to parse message`() {
+        val errors =
+            listOf<Throwable>(
+                SAXParseException("mismatched tag", null, null),
+                ParsingFeedException("Invalid XML"),
+            )
+        errors.forEach {
+            assertEquals(
+                "expected parse message for ${it::class.java.simpleName}",
+                SubscribeError.Text(R.string.subscribe_error_parse),
+                it.toSubscribeError(),
+            )
+        }
+    }
+
+    @Test
+    fun `other io exceptions keep their original message`() {
+        val error = IOException("boom").toSubscribeError()
+        assertEquals(SubscribeError.Raw("boom"), error)
+    }
+
+    @Test
+    fun `generic exceptions keep their original message`() {
+        val error = IllegalStateException("unexpected").toSubscribeError()
+        assertEquals(SubscribeError.Raw("unexpected"), error)
+    }
+}

app/src/test/resources/fixtures/statuspage_history.atom

@@ -0,0 +1,35 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<feed xml:lang="en-US" xmlns="http://www.w3.org/2005/Atom">
+  <id>tag:status.example.com,2005:/history</id>
+  <link rel="alternate" type="text/html" href="https://status.example.com"/>
+  <link rel="self" type="application/atom+xml" href="https://status.example.com/history.atom"/>
+  <title>Example Status - Incident History</title>
+  <updated>2026-09-03T09:04:16Z</updated>
+  <author>
+    <name>Example</name>
+  </author>
+  <entry>
+    <id>tag:status.example.com,2005:Incident/31327560</id>
+    <published>2026-09-01T16:01:21Z</published>
+    <updated>2026-09-01T16:01:21Z</updated>
+    <link rel="alternate" type="text/html" href="https://status.example.com/incidents/jk2dy5h9yp3m"/>
+    <title>Delays in commit processing</title>
+    <content type="html">&lt;p&gt; &lt;small&gt;Sep &lt;var data-var='date'&gt; 1&lt;/var&gt;, &lt;var data-var='time'&gt;16:01&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Resolved&lt;/strong&gt; - This incident has been resolved. &lt;/p&gt; &lt;p&gt; &lt;small&gt;Sep &lt;var data-var='date'&gt; 1&lt;/var&gt;, &lt;var data-var='time'&gt;15:00&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Investigating&lt;/strong&gt; - We are investigating reports of degraded performance. &lt;/p&gt;</content>
+  </entry>
+  <entry>
+    <id>tag:status.example.com,2005:Incident/31316411</id>
+    <published>2026-08-31T09:58:14Z</published>
+    <updated>2026-08-31T09:58:14Z</updated>
+    <link rel="alternate" type="text/html" href="https://status.example.com/incidents/7fxts6gmq5gr"/>
+    <title>Elevated rate of errors</title>
+    <content type="html">&lt;p&gt; &lt;small&gt;Aug &lt;var data-var='date'&gt;31&lt;/var&gt;, &lt;var data-var='time'&gt;09:58&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Resolved&lt;/strong&gt; - This incident has been resolved. &lt;br /&gt;&lt;br /&gt;We will continue monitoring to ensure stability. &lt;/p&gt;</content>
+  </entry>
+  <entry>
+    <id>tag:status.example.com,2005:Incident/31285481</id>
+    <published>2026-08-27T19:44:08Z</published>
+    <updated>2026-08-31T22:46:13Z</updated>
+    <link rel="alternate" type="text/html" href="https://status.example.com/incidents/5bn0vk444m1w"/>
+    <title>Disruption with billing</title>
+    <content type="html">&lt;p&gt; &lt;small&gt;Aug &lt;var data-var='date'&gt;27&lt;/var&gt;, &lt;var data-var='time'&gt;19:44&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Resolved&lt;/strong&gt; - On August 26, billing experienced degraded performance. &lt;br /&gt;&lt;br /&gt;This was caused by a concentrated workload. &lt;/p&gt;</content>
+  </entry>
+</feed>