fix: add fallback moderation in case openai goes down

src/backend/src/modules/puterai/AIChatService.js

@@ -6,6 +6,7 @@ const { DB_WRITE } = require("../../services/database/consts");
 const { TypeSpec } = require("../../services/drivers/meta/Construct");
 const { TypedValue } = require("../../services/drivers/meta/Runtime");
 const { Context } = require("../../util/context");
+const { AsModeration } = require("./lib/AsModeration");
 
 // Maximum number of fallback attempts when a model fails, including the first attempt
 const MAX_FALLBACKS = 3 + 1; // includes first attempt
@@ -489,11 +490,6 @@ class AIChatService extends BaseService {
     * Returns true if OpenAI service is unavailable or all messages pass moderation.
     */
     async moderate ({ messages }) {
-        const svc_openai = this.services.get('openai-completion');
-
-        // We can't use moderation of openai service isn't available
-        if ( ! svc_openai ) return true;
-        
         for ( const msg of messages ) {
             const texts = [];
             if ( typeof msg.content === 'string' ) texts.push(msg.content);
@@ -508,8 +504,39 @@ class AIChatService extends BaseService {
             
             const fulltext = texts.join('\n');
             
-            const mod_result = await svc_openai.check_moderation(fulltext);
+            let mod_last_error = null;
-            if ( mod_result.flagged ) return false;
+            let mod_result = null;
+            try {
+                const svc_openai = this.services.get('openai-completion');
+                mod_result = await svc_openai.check_moderation(fulltext);
+                if ( mod_result.flagged ) return false;
+            } catch (e) {
+                console.error(e);
+                mod_last_error = e;
+            }
+            try {
+                const svc_claude = this.services.get('claude');
+                const chat = svc_claude.as('puter-chat-completion');       
+                const mod = new AsModeration({
+                    chat,
+                    model: 'claude-3-haiku-20240307',
+                })
+                if ( ! await mod.moderate(fulltext) ) {
+                    return false;
+                }
+                mod_last_error = null;
+            } catch (e) {
+                console.error(e);
+                mod_last_error = e;
+            }
+            
+            if ( mod_last_error ) {
+                this.log.error('moderation error', {
+                    fulltext,
+                    mod_last_error,
+                });
+                throw new Error('no working moderation service');
+            }
         }
         return true;
     }

src/backend/src/modules/puterai/lib/AsModeration.js

@@ -0,0 +1,77 @@
+const { default: dedent } = require("dedent");
+
+class AsModeration {
+    constructor ({ chat, model }) {
+        this.chat = chat;
+        this.model = model;
+    }
+    
+    async moderate (text) {
+        // copied from Anthropic documentation
+        // https://docs.anthropic.com/en/docs/about-claude/use-case-guides/content-moderation
+        const unsafe_categories = [
+            'Child Exploitation',
+            'Conspiracy Theories',
+            'Hate',
+            'Indiscriminate Weapons', 
+            'Intellectual Property',
+            'Non-Violent Crimes', 
+            'Privacy',
+            'Self-Harm',
+            'Sex Crimes',
+            'Sexual Content',
+            'Specialized Advice',
+            'Violent Crimes'
+        ];
+        
+        const unsafe_category_str = unsafe_categories.join('\n');
+        
+        const assessment_prompt = dedent(`
+            Determine whether the following message warrants moderation, 
+            based on the unsafe categories outlined below.
+            
+            Message:
+            <message>
+            ${text
+                .replace('<', '&lt;')
+                .replace('>', '&gt;')
+            }
+            </message>
+        
+            Unsafe Categories:
+            <categories>
+            ${unsafe_category_str}
+            </categories>
+        
+            Respond with ONLY a JSON object, using the format below:
+            {{
+            "violation": <Boolean field denoting whether the message should be moderated>,
+            "categories": [Comma-separated list of violated categories],
+            "explanation": [Optional. Only include if there is a violation.]
+            }}
+        `);
+        
+        const result = await this.chat.complete({
+            messages: [
+                {
+                    role: 'user',
+                    content: assessment_prompt,
+                }
+            ]
+        });
+        
+        console.log('result???', require('util').inspect(result, { depth: null }));
+        
+        const str = result.message?.content?.[0]?.text ??
+            result.messages?.[0]?.content?.[0]?.text ??
+            '{ "violation": true }';
+        
+        const parsed = JSON.parse(str);
+        console.log('parsed?', parsed);
+        return ! parsed.violation;
+    }
+}
+
+module.exports = {
+    AsModeration,
+};