Truncate logs to a limit

app/controllers/general.php

@@ -618,7 +618,19 @@ function router(App $utopia, Database $dbForPlatform, callable $getProjectDB, Sw
             /** Update execution status */
             $status = $executionResponse['statusCode'] >= 500 ? 'failed' : 'completed';
             $execution->setAttribute('status', $status);
-            $execution->setAttribute('logs', $executionResponse['logs']);
+
+            // Truncate logs if they exceed the limit
+            $maxLogLength = APP_FUNCTION_LOG_LENGTH_LIMIT;
+            $logs = $executionResponse['logs'] ?? '';
+
+            if (\is_string($logs) && \strlen($logs) > $maxLogLength) {
+                $warningMessage = "\n[WARNING] Logs truncated. The output exceeded {$maxLogLength} characters.";
+                $warningLength = \strlen($warningMessage);
+                $maxContentLength = $maxLogLength - $warningLength;
+                $logs = \substr($logs, 0, $maxContentLength) . $warningMessage;
+            }
+
+            $execution->setAttribute('logs', $logs);
             $execution->setAttribute('errors', $executionResponse['errors']);
             $execution->setAttribute('responseStatusCode', $executionResponse['statusCode']);
             $execution->setAttribute('responseHeaders', $headersFiltered);

app/init/constants.php

@@ -143,6 +143,7 @@ const APP_AUTH_TYPE_KEY = 'Key';
 const APP_AUTH_TYPE_ADMIN = 'Admin';
 // Response related
 const MAX_OUTPUT_CHUNK_SIZE = 10 * 1024 * 1024; // 10MB
+const APP_FUNCTION_LOG_LENGTH_LIMIT = 1000000;
 // Function headers
 const FUNCTION_ALLOWLIST_HEADERS_REQUEST = ['content-type', 'agent', 'content-length', 'host'];
 const FUNCTION_ALLOWLIST_HEADERS_RESPONSE = ['content-type', 'content-length'];

src/Appwrite/Platform/Modules/Functions/Http/Executions/Create.php

@@ -423,12 +423,22 @@ class Create extends Base
                 }
             }
 
+            $maxLogLength = APP_FUNCTION_LOG_LENGTH_LIMIT;
+            $logs = $executionResponse['logs'] ?? '';
+
+            if (\is_string($logs) && \strlen($logs) > $maxLogLength) {
+                $warningMessage = "\n[WARNING] Logs truncated. The output exceeded {$maxLogLength} characters.";
+                $warningLength = \strlen($warningMessage);
+                $maxContentLength = $maxLogLength - $warningLength;
+                $logs = \substr($logs, 0, $maxContentLength) . $warningMessage;
+            }
+
             /** Update execution status */
             $status = $executionResponse['statusCode'] >= 500 ? 'failed' : 'completed';
             $execution->setAttribute('status', $status);
             $execution->setAttribute('responseStatusCode', $executionResponse['statusCode']);
             $execution->setAttribute('responseHeaders', $headersFiltered);
-            $execution->setAttribute('logs', $executionResponse['logs']);
+            $execution->setAttribute('logs', $logs);
             $execution->setAttribute('errors', $executionResponse['errors']);
             $execution->setAttribute('duration', $executionResponse['duration']);
         } catch (\Throwable $th) {

src/Appwrite/Platform/Workers/Functions.php

@@ -551,11 +551,21 @@ class Functions extends Action
             }
 
             /** Update execution status */
+            $maxLogLength = APP_FUNCTION_LOG_LENGTH_LIMIT;
+            $logs = $executionResponse['logs'] ?? '';
+
+            if (\is_string($logs) && \strlen($logs) > $maxLogLength) {
+                $warningMessage = "\n[WARNING] Logs truncated. The output exceeded {$maxLogLength} characters.";
+                $warningLength = \strlen($warningMessage);
+                $maxContentLength = $maxLogLength - $warningLength;
+                $logs = \substr($logs, 0, $maxContentLength) . $warningMessage;
+            }
+
             $execution
                 ->setAttribute('status', $status)
                 ->setAttribute('responseStatusCode', $executionResponse['statusCode'])
                 ->setAttribute('responseHeaders', $headersFiltered)
-                ->setAttribute('logs', $executionResponse['logs'])
+                ->setAttribute('logs', $logs)
                 ->setAttribute('errors', $executionResponse['errors'])
                 ->setAttribute('duration', $executionResponse['duration']);
         } catch (\Throwable $th) {

tests/e2e/Services/Functions/FunctionsCustomServerTest.php

@@ -2282,4 +2282,34 @@ class FunctionsCustomServerTest extends Scope
 
         $this->cleanupFunction($functionId);
     }
+
+    public function testLogTruncation(): void
+    {
+        $functionId = $this->setupFunction([
+            'functionId' => ID::unique(),
+            'name' => 'Test Log Truncation',
+            'runtime' => 'node-22',
+            'entrypoint' => 'index.js',
+            'timeout' => 15,
+        ]);
+
+        $this->setupDeployment($functionId, [
+            'code' => $this->packageFunction('log-truncation'),
+            'activate' => true
+        ]);
+
+        $execution = $this->createExecution($functionId, [
+            'async' => 'false'
+        ]);
+
+        $this->assertEquals(201, $execution['headers']['status-code']);
+        $this->assertEquals(200, $execution['body']['responseStatusCode']);
+
+        // Verify logs are truncated and warning message is present
+        $logs = $execution['body']['logs'];
+        $this->assertLessThanOrEqual(APP_FUNCTION_LOG_LENGTH_LIMIT, strlen($logs));
+        $this->assertStringContainsString('[WARNING] Logs truncated', $logs);
+
+        $this->cleanupFunction($functionId);
+    }
 }

tests/resources/functions/log-truncation/index.js

@@ -0,0 +1,13 @@
+module.exports = async(context) => {
+  // Create a string that is 1000001 characters long (exceeds the 1000000 limit)
+  const longString = 'a'.repeat(1000001);
+
+  context.log(longString);
+
+  return context.res.json({
+    motto: 'Build like a team of hundreds_',
+    learn: 'https://appwrite.io/docs',
+    connect: 'https://appwrite.io/discord',
+    getInspired: 'https://builtwith.appwrite.io',
+  });
+};