feat: add session resumption to codex

registry/coder-labs/modules/codex/README.md

@@ -13,7 +13,7 @@ Run Codex CLI in your workspace to access OpenAI's models through the Codex inte
 ```tf
 module "codex" {
   source         = "registry.coder.com/coder-labs/codex/coder"
-  version        = "3.0.0"
+  version        = "3.1.0"
   agent_id       = coder_agent.example.id
   openai_api_key = var.openai_api_key
   workdir        = "/home/coder/project"
@@ -33,7 +33,7 @@ module "codex" {
 module "codex" {
   count          = data.coder_workspace.me.start_count
   source         = "registry.coder.com/coder-labs/codex/coder"
-  version        = "3.0.0"
+  version        = "3.1.0"
   agent_id       = coder_agent.example.id
   openai_api_key = "..."
   workdir        = "/home/coder/project"
@@ -61,7 +61,7 @@ module "coder-login" {
 
 module "codex" {
   source         = "registry.coder.com/coder-labs/codex/coder"
-  version        = "3.0.0"
+  version        = "3.1.0"
   agent_id       = coder_agent.example.id
   openai_api_key = "..."
   ai_prompt      = data.coder_parameter.ai_prompt.value
@@ -84,6 +84,7 @@ module "codex" {
 - **System Prompt**: If `codex_system_prompt` is set, writes the prompt to `AGENTS.md` in the `~/.codex/` directory
 - **Start**: Launches Codex CLI in the specified directory, wrapped by AgentAPI
 - **Configuration**: Sets `OPENAI_API_KEY` environment variable and passes `--model` flag to Codex CLI (if variables provided)
+- **Session Continuity**: When `continue = true` (default), the module automatically tracks task sessions in `~/.codex/.codex-task-session`. On workspace restart, it resumes the existing session with full conversation history. Set `continue = false` to always start fresh sessions.
 
 ## Configuration
 
@@ -107,7 +108,7 @@ For custom Codex configuration, use `base_config_toml` and/or `additional_mcp_se
 ```tf
 module "codex" {
   source  = "registry.coder.com/coder-labs/codex/coder"
-  version = "3.0.0"
+  version = "3.1.0"
   # ... other variables ...
 
   # Override default configuration

registry/coder-labs/modules/codex/main.test.ts

@@ -368,4 +368,39 @@ describe("codex", async () => {
     expect(prompt.exitCode).not.toBe(0);
     expect(prompt.stderr).toContain("No such file or directory");
   });
+
+  test("codex-continue-resume-existing-session", async () => {
+    const { id } = await setup({
+      moduleVariables: {
+        continue: "true",
+        ai_prompt: "test prompt",
+      },
+    });
+
+    const workdir = "/home/coder";
+    const mockSessionId = "019a1234-5678-9abc-def0-123456789012";
+    const trackingFile = "/home/coder/.codex/.codex-task-session";
+
+    await execContainer(id, ["mkdir", "-p", "/home/coder/.codex"]);
+    await execContainer(id, [
+      "bash",
+      "-c",
+      `echo "${workdir}|${mockSessionId}" > ${trackingFile}`,
+    ]);
+
+    await execModuleScript(id);
+
+    const startLog = await execContainer(id, [
+      "bash",
+      "-c",
+      "cat /home/coder/.codex-module/agentapi-start.log",
+    ]);
+    expect(startLog.stdout).toContain("Found existing task session");
+    expect(startLog.stdout).toContain(mockSessionId);
+    expect(startLog.stdout).toContain("Resuming existing session");
+    expect(startLog.stdout).toContain(
+      `Starting Codex with arguments: --model gpt-4-turbo resume ${mockSessionId}`,
+    );
+    expect(startLog.stdout).not.toContain("test prompt");
+  });
 });

registry/coder-labs/modules/codex/main.tf

@@ -137,6 +137,12 @@ variable "ai_prompt" {
   default     = ""
 }
 
+variable "continue" {
+  type        = bool
+  description = "Automatically continue existing sessions on workspace restart. When true, resumes existing conversation if found, otherwise runs prompt or starts new session. When false, always starts fresh (ignores existing sessions)."
+  default     = true
+}
+
 variable "codex_system_prompt" {
   type        = string
   description = "System instructions written to AGENTS.md in the ~/.codex directory"
@@ -187,8 +193,9 @@ module "agentapi" {
      ARG_OPENAI_API_KEY='${var.openai_api_key}' \
      ARG_REPORT_TASKS='${var.report_tasks}' \
      ARG_CODEX_MODEL='${var.codex_model}' \
-     ARG_CODEX_START_DIRECTORY='${var.workdir}' \
+     ARG_CODEX_START_DIRECTORY='${local.workdir}' \
      ARG_CODEX_TASK_PROMPT='${base64encode(var.ai_prompt)}' \
+     ARG_CONTINUE='${var.continue}' \
      /tmp/start.sh
    EOT
 
@@ -206,7 +213,7 @@ module "agentapi" {
     ARG_BASE_CONFIG_TOML='${base64encode(var.base_config_toml)}' \
     ARG_ADDITIONAL_MCP_SERVERS='${base64encode(var.additional_mcp_servers)}' \
     ARG_CODER_MCP_APP_STATUS_SLUG='${local.app_slug}' \
-    ARG_CODEX_START_DIRECTORY='${var.workdir}' \
+    ARG_CODEX_START_DIRECTORY='${local.workdir}' \
     ARG_CODEX_INSTRUCTION_PROMPT='${base64encode(var.codex_system_prompt)}' \
     /tmp/install.sh
   EOT

registry/coder-labs/modules/codex/scripts/start.sh

@@ -3,6 +3,7 @@
 source "$HOME"/.bashrc
 set -o errexit
 set -o pipefail
+
 command_exists() {
   command -v "$1" > /dev/null 2>&1
 }
@@ -16,60 +17,195 @@ fi
 printf "Version: %s\n" "$(codex --version)"
 set -o nounset
 ARG_CODEX_TASK_PROMPT=$(echo -n "$ARG_CODEX_TASK_PROMPT" | base64 -d)
+ARG_CONTINUE=${ARG_CONTINUE:-true}
 
 echo "=== Codex Launch Configuration ==="
 printf "OpenAI API Key: %s\n" "$([ -n "$ARG_OPENAI_API_KEY" ] && echo "Provided" || echo "Not provided")"
 printf "Codex Model: %s\n" "${ARG_CODEX_MODEL:-"Default"}"
 printf "Start Directory: %s\n" "$ARG_CODEX_START_DIRECTORY"
 printf "Has Task Prompt: %s\n" "$([ -n "$ARG_CODEX_TASK_PROMPT" ] && echo "Yes" || echo "No")"
 printf "Report Tasks: %s\n" "$ARG_REPORT_TASKS"
+printf "Continue Sessions: %s\n" "$ARG_CONTINUE"
 echo "======================================"
 set +o nounset
-CODEX_ARGS=()
 
-if command_exists codex; then
-  printf "Codex is installed\n"
-else
-  printf "Error: Codex is not installed. Please enable install_codex or install it manually\n"
-  exit 1
-fi
+SESSION_TRACKING_FILE="$HOME/.codex/.codex-task-session"
 
-if [ -d "${ARG_CODEX_START_DIRECTORY}" ]; then
-  printf "Directory '%s' exists. Changing to it.\\n" "${ARG_CODEX_START_DIRECTORY}"
-  cd "${ARG_CODEX_START_DIRECTORY}" || {
-    printf "Error: Could not change to directory '%s'.\\n" "${ARG_CODEX_START_DIRECTORY}"
-    exit 1
-  }
-else
-  printf "Directory '%s' does not exist. Creating and changing to it.\\n" "${ARG_CODEX_START_DIRECTORY}"
-  mkdir -p "${ARG_CODEX_START_DIRECTORY}" || {
-    printf "Error: Could not create directory '%s'.\\n" "${ARG_CODEX_START_DIRECTORY}"
-    exit 1
-  }
-  cd "${ARG_CODEX_START_DIRECTORY}" || {
-    printf "Error: Could not change to directory '%s'.\\n" "${ARG_CODEX_START_DIRECTORY}"
+find_session_for_directory() {
+  local target_dir="$1"
+
+  if [ ! -f "$SESSION_TRACKING_FILE" ]; then
+    return 1
+  fi
+
+  local session_id=$(grep "^$target_dir|" "$SESSION_TRACKING_FILE" | cut -d'|' -f2 | head -1)
+
+  if [ -n "$session_id" ]; then
+    echo "$session_id"
+    return 0
+  fi
+
+  return 1
+}
+
+store_session_mapping() {
+  local dir="$1"
+  local session_id="$2"
+
+  mkdir -p "$(dirname "$SESSION_TRACKING_FILE")"
+
+  if [ -f "$SESSION_TRACKING_FILE" ]; then
+    grep -v "^$dir|" "$SESSION_TRACKING_FILE" > "$SESSION_TRACKING_FILE.tmp" 2> /dev/null || true
+    mv "$SESSION_TRACKING_FILE.tmp" "$SESSION_TRACKING_FILE"
+  fi
+
+  echo "$dir|$session_id" >> "$SESSION_TRACKING_FILE"
+}
+
+find_recent_session_file() {
+  local target_dir="$1"
+  local sessions_dir="$HOME/.codex/sessions"
+
+  if [ ! -d "$sessions_dir" ]; then
+    return 1
+  fi
+
+  local latest_file=""
+  local latest_time=0
+
+  while IFS= read -r session_file; do
+    local file_time=$(stat -c %Y "$session_file" 2> /dev/null || stat -f %m "$session_file" 2> /dev/null || echo "0")
+    local first_line=$(head -n 1 "$session_file" 2> /dev/null)
+    local session_cwd=$(echo "$first_line" | grep -o '"cwd":"[^"]*"' | cut -d'"' -f4)
+
+    if [ "$session_cwd" = "$target_dir" ] && [ "$file_time" -gt "$latest_time" ]; then
+      latest_file="$session_file"
+      latest_time="$file_time"
+    fi
+  done < <(find "$sessions_dir" -type f -name "*.jsonl" 2> /dev/null)
+
+  if [ -n "$latest_file" ]; then
+    local first_line=$(head -n 1 "$latest_file")
+    local session_id=$(echo "$first_line" | grep -o '"id":"[^"]*"' | cut -d'"' -f4)
+    if [ -n "$session_id" ]; then
+      echo "$session_id"
+      return 0
+    fi
+  fi
+
+  return 1
+}
+
+wait_for_session_file() {
+  local target_dir="$1"
+  local max_attempts=20
+  local attempt=0
+
+  while [ $attempt -lt $max_attempts ]; do
+    local session_id=$(find_recent_session_file "$target_dir" 2> /dev/null || echo "")
+    if [ -n "$session_id" ]; then
+      echo "$session_id"
+      return 0
+    fi
+    sleep 0.5
+    attempt=$((attempt + 1))
+  done
+
+  return 1
+}
+
+validate_codex_installation() {
+  if command_exists codex; then
+    printf "Codex is installed\n"
+  else
+    printf "Error: Codex is not installed. Please enable install_codex or install it manually\n"
     exit 1
-  }
-fi
+  fi
+}
 
-if [ -n "$ARG_CODEX_MODEL" ]; then
-  CODEX_ARGS+=("--model" "$ARG_CODEX_MODEL")
-fi
+setup_workdir() {
+  if [ -d "${ARG_CODEX_START_DIRECTORY}" ]; then
+    printf "Directory '%s' exists. Changing to it.\\n" "${ARG_CODEX_START_DIRECTORY}"
+    cd "${ARG_CODEX_START_DIRECTORY}" || {
+      printf "Error: Could not change to directory '%s'.\\n" "${ARG_CODEX_START_DIRECTORY}"
+      exit 1
+    }
+  else
+    printf "Directory '%s' does not exist. Creating and changing to it.\\n" "${ARG_CODEX_START_DIRECTORY}"
+    mkdir -p "${ARG_CODEX_START_DIRECTORY}" || {
+      printf "Error: Could not create directory '%s'.\\n" "${ARG_CODEX_START_DIRECTORY}"
+      exit 1
+    }
+    cd "${ARG_CODEX_START_DIRECTORY}" || {
+      printf "Error: Could not change to directory '%s'.\\n" "${ARG_CODEX_START_DIRECTORY}"
+      exit 1
+    }
+  fi
+}
+
+build_codex_args() {
+  CODEX_ARGS=()
 
-if [ -n "$ARG_CODEX_TASK_PROMPT" ]; then
-  printf "Running the task prompt %s\n" "$ARG_CODEX_TASK_PROMPT"
-  if [ "${ARG_REPORT_TASKS}" == "true" ]; then
-    PROMPT="Complete the task at hand in one go. Every step of the way, report your progress using coder_report_task tool with proper summary and statuses. Your task at hand: $ARG_CODEX_TASK_PROMPT"
+  if [ -n "$ARG_CODEX_MODEL" ]; then
+    CODEX_ARGS+=("--model" "$ARG_CODEX_MODEL")
+  fi
+
+  if [ "$ARG_CONTINUE" = "true" ]; then
+    existing_session=$(find_session_for_directory "$ARG_CODEX_START_DIRECTORY" 2> /dev/null || echo "")
+
+    if [ -n "$existing_session" ]; then
+      printf "Found existing task session for this directory: %s\n" "$existing_session"
+      printf "Resuming existing session...\n"
+      CODEX_ARGS+=("resume" "$existing_session")
+    else
+      printf "No existing task session found for this directory\n"
+      printf "Starting new task session...\n"
+
+      if [ -n "$ARG_CODEX_TASK_PROMPT" ]; then
+        if [ "${ARG_REPORT_TASKS}" == "true" ]; then
+          PROMPT="Complete the task at hand in one go. Every step of the way, report your progress using coder_report_task tool with proper summary and statuses. Your task at hand: $ARG_CODEX_TASK_PROMPT"
+        else
+          PROMPT="Your task at hand: $ARG_CODEX_TASK_PROMPT"
+        fi
+        CODEX_ARGS+=("$PROMPT")
+      fi
+    fi
   else
-    PROMPT="Your task at hand: $ARG_CODEX_TASK_PROMPT"
+    printf "Continue disabled, starting fresh session\n"
+
+    if [ -n "$ARG_CODEX_TASK_PROMPT" ]; then
+      if [ "${ARG_REPORT_TASKS}" == "true" ]; then
+        PROMPT="Complete the task at hand in one go. Every step of the way, report your progress using coder_report_task tool with proper summary and statuses. Your task at hand: $ARG_CODEX_TASK_PROMPT"
+      else
+        PROMPT="Your task at hand: $ARG_CODEX_TASK_PROMPT"
+      fi
+      CODEX_ARGS+=("$PROMPT")
+    fi
   fi
-  CODEX_ARGS+=("$PROMPT")
-else
-  printf "No task prompt given.\n"
-fi
+}
+
+capture_session_id() {
+  if [ "$ARG_CONTINUE" = "true" ] && [ -z "$existing_session" ]; then
+    printf "Capturing new session ID...\n"
+    new_session=$(wait_for_session_file "$ARG_CODEX_START_DIRECTORY" || echo "")
+
+    if [ -n "$new_session" ]; then
+      store_session_mapping "$ARG_CODEX_START_DIRECTORY" "$new_session"
+      printf "✓ Session tracked: %s\n" "$new_session"
+      printf "This session will be automatically resumed on next restart\n"
+    else
+      printf "⚠ Could not capture session ID after 10s timeout\n"
+    fi
+  fi
+}
+
+start_codex() {
+  printf "Starting Codex with arguments: %s\n" "${CODEX_ARGS[*]}"
+  agentapi server --term-width 67 --term-height 1190 -- codex "${CODEX_ARGS[@]}" &
+  capture_session_id
+}
 
-# Terminal dimensions optimized for Coder Tasks UI sidebar:
-# - Width 67: fits comfortably in sidebar
-# - Height 1190: adjusted due to Codex terminal height bug
-printf "Starting Codex with arguments: %s\n" "${CODEX_ARGS[*]}"
-agentapi server --term-width 67 --term-height 1190 -- codex "${CODEX_ARGS[@]}"
+validate_codex_installation
+setup_workdir
+build_codex_args
+start_codex