Skip to content
Kward Search API index

Class: Kward::SessionStore

Inherits:
Object
  • Object
show all
Defined in:
lib/kward/session_store.rb

Overview

JSONL-backed persistence for CLI and RPC conversations.

A session file is an append-only event log: a header record, message/tree records, metadata changes, memory state, tool execution metadata, labels, and branch navigation. SessionStore owns disk layout and reconstruction of a Conversation; frontends own when to create, resume, clone, compact, or delete sessions.

The tree fields (id, parentId, leaf records, labels) are part of the persisted user-data contract. Keep backward compatibility in mind before changing record shapes, and prefer adding records over rewriting existing files.

Defined Under Namespace

Classes: Session, SessionInfo

Constant Summary collapse

VERSION = 
2
LAST_SESSION_FILENAME = 
"last_session.json"
NON_ACTIVITY_RECORD_TYPES = 
%w[session session_info system_prompt].freeze
RECORD_TYPE_PATTERN = 
/\A\{\s*"type"\s*:\s*"([^"]+)"/
RECORD_TIMESTAMP_PATTERN = 
/"timestamp"\s*:\s*"([^"]+)"/

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(config_dir: ConfigFiles.config_dir, cwd: Dir.pwd) ⇒ SessionStore

Creates an object for JSONL session persistence.



204
205
206
207
 
# File 'lib/kward/session_store.rb', line 204

def initialize(config_dir: ConfigFiles.config_dir, cwd: Dir.pwd)
  @config_dir = config_dir
  @cwd = File.expand_path(cwd)
end

Instance Attribute Details

#config_dir ⇒ String (readonly)

Returns configuration directory containing session and tab files.

Returns:

  • (String) —

    configuration directory containing session and tab files



213
214
215
 
# File 'lib/kward/session_store.rb', line 213

def config_dir
  @config_dir
end

#cwd ⇒ String (readonly)

Returns workspace directory this store lists and creates sessions for.

Returns:

  • (String) —

    workspace directory this store lists and creates sessions for



210
211
212
 
# File 'lib/kward/session_store.rb', line 210

def cwd
  @cwd
end

Class Method Details

.safe_cwd(cwd) ⇒ Object 



521
522
523
 
# File 'lib/kward/session_store.rb', line 521

def self.safe_cwd(cwd)
  "--#{File.expand_path(cwd).sub(%r{\A[/\\]}, "").gsub(%r{[/\\:]}, "-")}--"
end

Instance Method Details

#append_label_change(path, entry_id, label) ⇒ Object 



436
437
438
439
440
441
442
443
444
445
446
 
# File 'lib/kward/session_store.rb', line 436

def append_label_change(path, entry_id, label)
  record = {
    type: "label",
    id: next_entry_id(path),
    timestamp: Time.now.utc.iso8601(3),
    targetId: entry_id.to_s,
    label: label.to_s.strip.empty? ? nil : label.to_s.strip
  }
  append_record(path, record)
  record
end

#append_leaf_change(path, leaf_id) ⇒ Object 



426
427
428
429
430
431
432
433
434
 
# File 'lib/kward/session_store.rb', line 426

def append_leaf_change(path, leaf_id)
  record = {
    type: "leaf",
    timestamp: Time.now.utc.iso8601(3),
    targetId: leaf_id
  }
  append_record(path, record)
  record
end

#append_record(path, record) ⇒ Object 



496
497
498
499
500
501
 
# File 'lib/kward/session_store.rb', line 496

def append_record(path, record)
  File.open(path, "a", 0o600) do |file|
    file.write(JSON.generate(record))
    file.write("\n")
  end
end

#append_system_prompt_snapshot(path, system_message, reason: "changed", latest_hash: nil) ⇒ Object 



503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
 
# File 'lib/kward/session_store.rb', line 503

def append_system_prompt_snapshot(path, system_message, reason: "changed", latest_hash: nil)
  content = MessageAccess.content(system_message).to_s
  return latest_hash if content.empty?

  hash = system_prompt_hash(content)
  latest_hash ||= latest_system_prompt_hash(records_from_file(path))
  return latest_hash if latest_hash == hash

  append_record(path, {
    type: "system_prompt",
    timestamp: Time.now.utc.iso8601(3),
    reason: reason.to_s,
    hash: hash,
    content: content
  })
  hash
end

#build_tree_record(path, type, parent_id, fields = {}) ⇒ Hash

Builds a persisted tree record and assigns a stable entry id to messages.

Returns:

  • (Hash) —

    JSONL-ready tree record



414
415
416
417
418
419
420
421
422
423
424
 
# File 'lib/kward/session_store.rb', line 414

def build_tree_record(path, type, parent_id, fields = {})
  message = fields[:message]
  id = message_entry_id(message) || next_entry_id(path)
  assign_message_entry_id(message, id) if message.is_a?(Hash)
  {
    type: type,
    id: id,
    parentId: parent_id,
    timestamp: Time.now.utc.iso8601(3)
  }.merge(fields).delete_if { |_key, value| value.nil? }
end

#capture_branch(path) ⇒ Hash

Returns the complete persisted active branch for an explicit export-like consumer. Unlike #load, this does not attach a conversation or mutate the session file.

Returns:

  • (Hash) —

    session metadata, saved system-prompt snapshots, and active branch records



485
486
487
488
489
490
491
492
493
494
 
# File 'lib/kward/session_store.rb', line 485

def capture_branch(path)
  resolved_path = resolve_session_path(path)
  records = records_from_file(resolved_path)
  {
    path: resolved_path,
    header: session_header(records, resolved_path),
    system_prompts: records.select { |record| record["type"] == "system_prompt" },
    entries: branch_records(records)
  }
end

#capture_candidates ⇒ Object

Lists all persisted sessions under this config directory for an explicit user-selected operation such as skill capture. Unlike #recent, this is not scoped to the store's current workspace.



354
355
356
357
358
359
 
# File 'lib/kward/session_store.rb', line 354

def capture_candidates
  pattern = File.join(@config_dir, "sessions", "**", "*.jsonl")
  Dir.glob(pattern).filter_map { |path| session_info(path) }.sort_by(&:modified_at).reverse
rescue StandardError
  []
end

#create(provider: nil, model: nil, reasoning_effort: nil, parent_id: nil, parent_path: nil) ⇒ Object

Creates a new empty session file for the store's workspace directory.

Parent fields record clone/fork ancestry; they do not imply live coupling between files after creation.



219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
 
# File 'lib/kward/session_store.rb', line 219

def create(provider: nil, model: nil, reasoning_effort: nil, parent_id: nil, parent_path: nil)
  dir = session_dir
  FileUtils.mkdir_p(dir, mode: 0o700)
  created_at = Time.now.utc
  id = SecureRandom.uuid
  path = File.join(dir, "#{created_at.iso8601(3).tr(':', '-')}_#{id}.jsonl")
  header = {
    type: "session",
    version: VERSION,
    id: id,
    timestamp: created_at.iso8601(3),
    cwd: @cwd,
    provider: provider.to_s,
    model: model.to_s,
    reasoningEffort: reasoning_effort.to_s,
    parentId: parent_id.to_s,
    parentPath: parent_path.to_s
  }.delete_if { |_key, value| value.to_s.empty? }

  File.open(path, File::WRONLY | File::CREAT | File::EXCL, 0o600) do |file|
    file.write(JSON.generate(header))
    file.write("\n")
  end
  File.chmod(0o600, path)

  Session.new(store: self, id: id, path: path, cwd: @cwd, created_at: created_at, parent_id: parent_id, parent_path: parent_path, leaf_id: nil, modified_at: created_at)
end

#create_from_conversation(conversation, parent_session: nil) ⇒ Object 



247
248
249
250
251
252
253
 
# File 'lib/kward/session_store.rb', line 247

def create_from_conversation(conversation, parent_session: nil)
  session = create(provider: conversation.provider, model: conversation.model, reasoning_effort: conversation.reasoning_effort, parent_id: parent_session&.id, parent_path: parent_session&.path)
  session.rename(parent_session.name) unless parent_session&.name.to_s.strip.empty?
  persisted_messages(conversation).each { |message| session.append_message(message) }
  session.attach(conversation)
  session
end

#create_independent_from_conversation(conversation, parent_session: nil) ⇒ Object 



255
256
257
258
259
260
261
262
263
264
 
# File 'lib/kward/session_store.rb', line 255

def create_independent_from_conversation(conversation, parent_session: nil)
  create_independent_from_messages(
    persisted_messages(conversation),
    read_paths: Array(conversation.read_paths),
    provider: conversation.provider,
    model: conversation.model,
    reasoning_effort: conversation.reasoning_effort,
    parent_session: parent_session
  )
end

#create_independent_from_messages(messages, read_paths: [], provider: nil, model: nil, reasoning_effort: nil, parent_session: nil) ⇒ Array(Session, Conversation)

Creates a new session containing an independent copy of selected messages.

Used by clone/fork flows where the new conversation must preserve selected history but then diverge without mutating the source session file.

Parameters:

  • messages (Array<Hash>) —

    messages to persist into the new session

  • read_paths (Array<String>) (defaults to: []) —

    restored read-before-write paths

  • parent_session (Session, nil) (defaults to: nil) —

    optional source session metadata

Returns:



275
276
277
278
279
280
281
282
283
 
# File 'lib/kward/session_store.rb', line 275

def create_independent_from_messages(messages, read_paths: [], provider: nil, model: nil, reasoning_effort: nil, parent_session: nil)
  session = create(provider: provider, model: model, reasoning_effort: reasoning_effort, parent_id: parent_session&.id, parent_path: parent_session&.path)
  session.rename(parent_session.name) unless parent_session&.name.to_s.strip.empty?
  persisted = persistence_copy(messages)
  persisted.each { |message| session.append_message(message) }
  conversation = Conversation.new(messages: persistence_copy(persisted), read_paths: read_paths, workspace_root: @cwd, provider: provider, model: model, reasoning_effort: reasoning_effort)
  session.attach(conversation)
  [session, conversation]
end

#current_leaf(path) ⇒ String?

Returns current active tree leaf id.

Returns:

  • (String, nil) —

    current active tree leaf id



476
477
478
 
# File 'lib/kward/session_store.rb', line 476

def current_leaf(path)
  current_leaf_id(records_from_file(resolve_session_path(path)))
end

#delete_unused_session(session) ⇒ Boolean

Deletes an empty unnamed session file.

Returns:

  • (Boolean) —

    true when a file was removed



395
396
397
398
399
400
401
402
403
404
 
# File 'lib/kward/session_store.rb', line 395

def delete_unused_session(session)
  path = session.path
  return false if session_named?(session)
  return false unless unused_session_file?(path)

  File.delete(path)
  true
rescue StandardError
  false
end

#last_session_path ⇒ Object 



369
370
371
 
# File 'lib/kward/session_store.rb', line 369

def last_session_path
  File.join(session_dir, LAST_SESSION_FILENAME)
end

#load(path, workspace: Workspace.new, provider: nil, model: nil, reasoning_effort: nil) ⇒ Object

Loads a session file and reconstructs its current conversation leaf.

workspace is used both for the active root and to restore read-before-write paths from successful read tool results. If a session moved workspaces, load it through session_location first so the original cwd is respected.



300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
 
# File 'lib/kward/session_store.rb', line 300

def load(path, workspace: Workspace.new, provider: nil, model: nil, reasoning_effort: nil)
  resolved_path = resolve_session_path(path)
  records = records_from_file(resolved_path)
  header = session_header(records, resolved_path)

  leaf_id = current_leaf_id(records)
  messages = restored_messages(records)
  name = session_name(records)
  read_paths = restored_read_paths(messages, workspace)
  memory_state = restored_memory_state(records)

  runtime = session_runtime(records, header)
  conversation = Conversation.new(
    messages: messages,
    read_paths: read_paths,
    workspace_root: workspace.root,
    provider: runtime["provider"] || provider,
    model: runtime["model"] || model,
    reasoning_effort: runtime["reasoningEffort"] || reasoning_effort,
    session_memories: memory_state["sessionMemories"],
    last_memory_retrieval: memory_state["lastRetrieval"]
  )
  restore_tool_output_artifacts(records, conversation)
  conversation.mark_last_entry_compaction! if latest_record_type(records) == "compaction"
  created_at = parse_time(header["timestamp"]) || File.mtime(resolved_path)
  session = Session.new(
    store: self,
    id: header["id"],
    path: resolved_path,
    cwd: header["cwd"].to_s,
    created_at: created_at,
    name: name,
    parent_id: header["parentId"],
    parent_path: header["parentPath"],
    leaf_id: leaf_id,
    modified_at: session_modified_at(records, fallback: created_at),
    system_prompt_hash: latest_system_prompt_hash(records)
  )
  session.attach(conversation)
  [session, conversation]
end

#recent(limit: 20, keep_empty_path: nil) ⇒ Array<SessionInfo>

Lists recent non-empty sessions for this workspace.

Parameters:

  • limit (Integer, nil) (defaults to: 20) —

    maximum number of sessions, or nil for all

  • keep_empty_path (String, Array<String>, nil) (defaults to: nil) —

    live empty session path(s) to preserve while omitting them from results

Returns:



347
348
349
 
# File 'lib/kward/session_store.rb', line 347

def recent(limit: 20, keep_empty_path: nil)
  recent_sessions(limit: limit, keep_empty_path: keep_empty_path)
end

#recent_tree(limit: 20, keep_empty_path: nil) ⇒ Array<SessionInfo>

Lists recent sessions decorated with parent/branch display metadata.

Returns:

  • (Array<SessionInfo>) —

    recent sessions with tree depth fields



388
389
390
 
# File 'lib/kward/session_store.rb', line 388

def recent_tree(limit: 20, keep_empty_path: nil)
  decorate_tree(recent_sessions(limit: limit, keep_empty_path: keep_empty_path))
end

#remember_last_session(session) ⇒ Object

Persists the last active session pointer for workspace auto-resume.



362
363
364
365
366
367
 
# File 'lib/kward/session_store.rb', line 362

def remember_last_session(session)
  return unless session&.path

  FileUtils.mkdir_p(session_dir, mode: 0o700)
  PrivateFile.write_json(last_session_path, { "path" => File.expand_path(session.path), "timestamp" => Time.now.utc.iso8601(3) })
end

#remembered_last_session_path ⇒ String?

Returns remembered session path when the file still exists.

Returns:

  • (String, nil) —

    remembered session path when the file still exists



374
375
376
377
378
379
380
381
382
383
 
# File 'lib/kward/session_store.rb', line 374

def remembered_last_session_path
  return nil unless File.file?(last_session_path)

  path = JSON.parse(File.read(last_session_path))["path"].to_s
  return nil if path.empty? || !File.file?(path)

  path
rescue JSON::ParserError
  nil
end

#session_dir ⇒ Object 



406
407
408
 
# File 'lib/kward/session_store.rb', line 406

def session_dir
  File.join(@config_dir, "sessions", self.class.safe_cwd(@cwd))
end

#session_entries(path) ⇒ Array<Hash>

Returns flat tree records with resolved labels attached.

Returns:

  • (Array<Hash>) —

    flat tree records with resolved labels attached



455
456
457
458
459
460
461
462
463
464
465
466
 
# File 'lib/kward/session_store.rb', line 455

def session_entries(path)
  records = records_from_file(resolve_session_path(path))
  labels = labels_by_target(records)
  timestamps = label_timestamps_by_target(records)
  records.select { |record| tree_entry_record?(record) }.map do |record|
    id = record["id"].to_s
    record.dup.tap do |copy|
      copy["resolvedLabel"] = labels[id] if labels.key?(id)
      copy["labelTimestamp"] = timestamps[id] if timestamps.key?(id)
    end
  end
end

#session_entry(path, entry_id) ⇒ Hash?

Finds one persisted tree entry by id.

Returns:

  • (Hash, nil) 


471
472
473
 
# File 'lib/kward/session_store.rb', line 471

def session_entry(path, entry_id)
  session_entries(path).find { |record| record["id"].to_s == entry_id.to_s }
end

#session_location(path) ⇒ Hash

Resolves a user-provided path and returns the stored workspace location.

Returns:

  • (Hash) —

    :path and :cwd for loading the session safely



288
289
290
291
292
293
 
# File 'lib/kward/session_store.rb', line 288

def session_location(path)
  resolved_path = resolve_session_path(path)
  records = records_from_file(resolved_path)
  header = session_header(records, resolved_path)
  { path: resolved_path, cwd: header["cwd"].to_s.empty? ? @cwd : header["cwd"].to_s }
end

#session_tree(path) ⇒ Array<Hash>

Returns nested session tree roots for the given session file.

Returns:

  • (Array<Hash>) —

    nested session tree roots for the given session file



449
450
451
452
 
# File 'lib/kward/session_store.rb', line 449

def session_tree(path)
  records = records_from_file(resolve_session_path(path))
  build_session_tree(records)
end