From 059c6522b675636683cfd0cead250296d3bbd921 Mon Sep 17 00:00:00 2001
From: John Livingston <git@john-livingston.fr>
Date: Fri, 18 Nov 2022 17:48:20 +0100
Subject: [PATCH] Implements #37: diagnostic tools includes last lines from
 prosody error log files.

---
 CHANGELOG.md                     |  1 +
 server/lib/diagnostic/prosody.ts | 23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0191536d..b7530607 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -49,6 +49,7 @@ Peertube image.
 
 * Fix «autocolor» mecanism when no color provided (raised an error).
 * Fix #73: deleted message are shown when loading history.
+* Implements #37: diagnostic tools includes last lines from prosody error log files.
 
 ## 5.7.1
 
diff --git a/server/lib/diagnostic/prosody.ts b/server/lib/diagnostic/prosody.ts
index 13910c5f..691075a2 100644
--- a/server/lib/diagnostic/prosody.ts
+++ b/server/lib/diagnostic/prosody.ts
@@ -23,9 +23,11 @@ export async function diagProsody (test: string, options: RegisterServerOptions)
   // Testing the prosody config file.
   let prosodyPort: string
   let prosodyHost: string
+  let prosodyErrorLogPath: string
   try {
     const wantedConfig = await getProsodyConfig(options)
     const filePath = wantedConfig.paths.config
+    prosodyErrorLogPath = wantedConfig.paths.error
 
     result.messages.push(`Prosody will run on port '${wantedConfig.port}'`)
     prosodyPort = wantedConfig.port
@@ -163,6 +165,27 @@ export async function diagProsody (test: string, options: RegisterServerOptions)
     return result
   }
 
+  // Checking if there is a Prosody error log, and returning last lines.
+  try {
+    await fs.promises.access(prosodyErrorLogPath, fs.constants.R_OK) // throw an error if file does not exist.
+    result.messages.push(`The prosody error log (${prosodyErrorLogPath}) exists`)
+    const errorLogContent = await fs.promises.readFile(prosodyErrorLogPath, {
+      encoding: 'utf-8'
+    })
+
+    let logLines = errorLogContent.split(/\r?\n/)
+    if (logLines.length > 50) {
+      logLines = logLines.slice(-50)
+    }
+
+    result.debug.push({
+      title: 'Prosody error log (last 50 lines)',
+      message: logLines.join('\n')
+    })
+  } catch (error) {
+    // Error should be because file does not exists. This is not an error case, just ignoring.
+  }
+
   result.ok = true
   return result
 }