fix(core): restart opencode server on 3 cancels

If the user tries to cancel their request three times in a row, shutdown
the opencode server and then restart.

Getting the code working was a little bit tricky for two main issues:

1. If we try to do it on demand in api_client when the user sends a
prompt, then there's a race condition between that prompt getting
sent and when we get subscribed to server events. That race condition
can cause us to miss message/part events.

2. Some other listeners to opencode_server may trigger api_client calls
so we have to be extra careful to make sure base_url is set. That means
we can't rely solely on state.opencode_server notification to update
base_url but have to check it before using it.

Author: cameronr

lua/opencode/api_client.lua

@@ -14,21 +14,42 @@ function OpencodeApiClient.new(base_url)
   }, OpencodeApiClient)
 end
 
+---Ensure that base_url is set. Even thought we're subscribed to
+---state.opencode_server, we still need this check because
+---it's possible someone will try to make an api call in their event
+---handler (e.g. event_manager or header)
+---@return boolean
+function OpencodeApiClient:_ensure_base_url()
+  -- NOTE: eventhough we're subscribed opencode_server, we need this check for
+  -- base_url because the notification about opencode_server being set to
+  -- non-nil my not have gotten to us in time
+  if self.base_url then
+    return true
+  end
+
+  local state = require('opencode.state')
+
+  if not state.opencode_server then
+    state.opencode_server = server_job.ensure_server() --[[@as OpencodeServer]]
+    -- shouldn't normally happen but prevents error in replay tester
+    if not state.opencode_server then
+      return false
+    end
+  end
+
+  self.base_url = state.opencode_server.url:gsub('/$', '')
+  return true
+end
+
 --- Make a typed API call
 --- @param endpoint string The API endpoint path
 --- @param method string|nil HTTP method (default: 'GET')
 --- @param body table|nil|boolean Request body
 --- @param query table|nil Query parameters
 --- @return Promise<any> promise
 function OpencodeApiClient:_call(endpoint, method, body, query)
-  if not self.base_url then
-    local state = require('opencode.state')
-    state.opencode_server = server_job.ensure_server() --[[@as OpencodeServer]]
-    -- shouldn't normally happen but prevents error in replay tester
-    if not state.opencode_server then
-      return nil
-    end
-    self.base_url = state.opencode_server.url:gsub('/$', '')
+  if not self:_ensure_base_url() then
+    return nil
   end
   local url = self.base_url .. endpoint
 
@@ -361,10 +382,7 @@ end
 --- @param on_event fun(event: table) Event callback
 --- @return Job The streaming job handle
 function OpencodeApiClient:subscribe_to_events(directory, on_event)
-  if not self.base_url then
-    local state = require('opencode.state')
-    self.base_url = state.opencode_server.url:gsub('/$', '')
-  end
+  self:_ensure_base_url()
   local url = self.base_url .. '/event'
   if directory then
     url = url .. '?directory=' .. directory
@@ -403,13 +421,31 @@ function OpencodeApiClient:list_tools(provider, model, directory)
 end
 
 --- Create a factory function for the module
---- @param base_url string The base URL of the opencode server
+--- @param base_url? string The base URL of the opencode server
 --- @return OpencodeApiClient
 local function create_client(base_url)
-  return OpencodeApiClient.new(base_url)
-end
+  local state = require('opencode.state')
+
+  base_url = base_url or state.opencode_server and state.opencode_server.url
 
-local function instance() end
+  local api_client = OpencodeApiClient.new(base_url)
+
+  local function on_server_change(_, new_val, _)
+    -- NOTE: set base_url here if we can. we still need the check in _call
+    -- because the event firing on the server change may not have happened
+    -- before a caller is trying to make an api request, so the main benefit
+    -- of the subscription is setting base_url to nil when the server goes away
+    if new_val and new_val.url then
+      api_client.base_url = new_val.url
+    else
+      api_client.base_url = nil
+    end
+  end
+
+  state.subscribe('opencode_server', on_server_change)
+
+  return api_client
+end
 
 return {
   new = OpencodeApiClient.new,

lua/opencode/core.lua

@@ -1,15 +1,16 @@
 -- This file was written by an automated tool.
-local M = {}
 local state = require('opencode.state')
 local context = require('opencode.context')
 local session = require('opencode.session')
 local ui = require('opencode.ui.ui')
 local server_job = require('opencode.server_job')
 local input_window = require('opencode.ui.input_window')
 local util = require('opencode.util')
-local Promise = require('opencode.promise')
 local config = require('opencode.config')
 
+local M = {}
+M._abort_count = 0
+
 ---@param parent_id string?
 function M.select_session(parent_id)
   local all_sessions = session.get_all_workspace_sessions() or {}
@@ -137,6 +138,7 @@ function M.after_run(prompt)
   context.unload_attachments()
   state.last_sent_context = vim.deepcopy(context.context)
   require('opencode.history').write(prompt)
+  M._abort_count = 0
 end
 
 ---@param opts? SendMessageOpts
@@ -175,15 +177,23 @@ end
 function M.stop()
   if state.windows and state.active_session then
     if state.is_running() then
-      vim.notify('Aborting current request...', vim.log.levels.WARN)
+      M._abort_count = M._abort_count + 1
+      state.api_client:abort_session(state.active_session.id):wait()
 
-      -- FIXME: I think my understanding / logic was wrong here. We don't
-      -- just want to cancel our requests to the opencode server, we
-      -- want the opencode server to cance it's requests. Commenting out
-      -- this code for now and will do more testing
-      -- server_job.cancel_all_requests()
+      if M._abort_count >= 3 then
+        vim.notify('Re-starting Opencode server')
+        M._abort_count = 0
+        -- close existing server
+        state.opencode_server:shutdown():wait()
 
-      state.api_client:abort_session(state.active_session.id):wait()
+        -- start a new one
+        state.opencode_server = nil
+        state.job_count = 0
+
+        -- NOTE: start a new server here to make sure we're subscribed
+        -- to server events before a user sends a message
+        state.opencode_server = server_job.ensure_server() --[[@as OpencodeServer]]
+      end
     end
     require('opencode.ui.footer').clear()
     input_window.set_content('')
@@ -231,7 +241,7 @@ function M.setup()
     M.opencode_ok()
   end)
   local OpencodeApiClient = require('opencode.api_client')
-  state.api_client = OpencodeApiClient.new()
+  state.api_client = OpencodeApiClient.create()
 end
 
 return M