Load all task dates#

Get the start, end and duration of every scheduled task from one solve, for example to fill your UI when a project first opens.

By default, updates in a ScheduleResult is sparse: it lists only the tasks that moved. Set includeUnchanged and the same solve also reports the tasks that didn't move. You don't need a separate call.

Steps#

1. Pass includeUnchanged: true in the solve options:

   Copy

   const options = { includeUnchanged: true };
   

2. Pass the options to the solve that loads the data. Use project.solve(data, options) for a long-lived project, or schedule(data, options) for a one-shot job.

3. Read every entry of result.updates. Each entry has start_date, end_date and duration set.

The full example below schedules three tasks. review doesn't move, but it's still reported:

import { Project } from "plen-js";

const data = {
  tasks: [
    { id: "design", start_date: "2026-01-01", duration: 2 },
    { id: "build", start_date: "2026-01-01", duration: 1 },
    { id: "review", start_date: "2026-01-05", duration: 1 },
  ],
  links: [{ id: "design-build", source: "design", target: "build", type: "fs" }],
  // 24/7 time keeps the example dates easy to check.
  config: { use_calendars: false },
};

const options = { includeUnchanged: true };

const project = new Project();
const result = project.solve(data, options);

for (const update of result.updates) {
  console.log(update.id, `${update.start_date}..${update.end_date}`, update.duration);
}

Get the full list from an already solved project#

To reload every date later, call project.solve(null, options) with the same options. On a solved project with no pending edits, the call doesn't replan or change the accepted state, and baselineId stays the same:

const allDates = project.solve(null, { includeUnchanged: true });

Switch back to sparse results for the edits that follow. Leave out includeUnchanged to get only what changed:

const next = project.solve(null);

The result cache uses all of the solve options as its key. An includeUnchanged call never gets a cached sparse result, and a sparse call never gets a cached full one.

What is and isn't reported#

• The result includes every scheduled task: leaf tasks, summaries and milestones. Check the entry's kind ("task", "summary" or "milestone") to tell them apart.
• Tasks with unscheduled: true are never reported.
• leveling_delay and pauses never appear, because a solve doesn't change them.
• baselineId follows real changes only. Asking for unchanged tasks doesn't create a new baseline.
• With subtree, the result holds every task in the subtree, including the subtree tasks' ancestors. Tasks outside the subtree appear only when a sparse subtree solve would report them too, because they changed or were edited.
• On a project with a dependency cycle, nothing is scheduled. The result still lists every scheduled task, in model order, with its dates and duration as stored. subtree is ignored, and no entry has a reason, even with reasons: true.
• project.preview and project.level always return sparse updates.

Result#

The example prints one line per task, including review, which didn't move (the lines may come in a different order):

design 2026-01-01 00:00..2026-01-03 00:00 2
build 2026-01-03 00:00..2026-01-04 00:00 1
review 2026-01-05 00:00..2026-01-06 00:00 1

Without includeUnchanged, the same solve reports only build.

See Reading results for how to write the dates back into your model.