crates/forge_display/src/fixtures/code-01.md

Permission Checking Flow for Fetch Requests

Based on the codebase analysis, here's where permissions are checked before making a fetch request:

Flow Overview:

1. Entry Point: crates/forge_app/src/tool_executor.rs:336

   if env.enable_permissions && self.check_tool_permission(&tool_input, context).await?
   

2. Permission Check Method: crates/forge_app/src/tool_executor.rs:48-72

   • The check_tool_permission() method is called before executing any tool
   • It converts the tool catalog to a policy operation

3. Policy Operation Conversion: crates/forge_domain/src/tools/catalog.rs:680-684

   ToolCatalog::Fetch(input) => Some(crate::policies::PermissionOperation::Fetch {
       url: input.url.clone(),
       cwd,
       message: format!("Fetch content from URL: {}", input.url),
   })
   

4. Permission Decision: crates/forge_services/src/policy.rs:163-208

   • The check_operation_permission() method evaluates the fetch operation against policies
   • Uses PolicyEngine::can_perform() to check rules

5. Rule Matching: crates/forge_domain/src/policies/rule.rs:88-96

   (Rule::Fetch(rule), PermissionOperation::Fetch { url, cwd, message: _ }) => {
       let url_matches = match_pattern(&rule.url, url);
       let dir_matches = match &rule.dir {
           Some(wd_pattern) => match_pattern(wd_pattern, cwd),
           None => true,
       };
       url_matches && dir_matches
   }
   

6. Actual Fetch Execution: crates/forge_app/src/tool_executor.rs:282-284

   • Only executed if permission is granted

   ToolCatalog::Fetch(input) => {
       let output = self.services.fetch(input.url.clone(), input.raw).await?;
       (input, output).into()
   }
   

Key Points:

• Gating Condition: Permissions are only checked if env.enable_permissions is true
• Permission Denial: If denied, returns a "Permission Denied" error without executing the fetch
• Policy Types: Can be Allow, Deny, or Confirm (prompts user)
• Pattern Matching: Fetch rules match against URL patterns (e.g., "https://api.example.com/*")
• User Confirmation: If no policy matches, the user is prompted to Allow, Deny, or Remember the decision

The permission check is a gating mechanism that prevents the actual HTTP fetch from occurring unless explicitly allowed by the policy engine.