DHTMLX Planning Engine Documentation

ScheduleResult#

The plain object returned by schedule, Project#solve, Project#preview and Project#analyze. It lists the tasks whose dates changed, plus the conflicts, cycles and notes found in the plan. Analytics, overallocations and a load profile are added when requested or relevant.

Each call returns a fresh object with keys in sorted order. It shares nothing with the input or the project. Date fields are "YYYY-MM-DD HH:MM" strings, or local Date objects when the project was created with dates: "date".

Fields#

Field Type Description
baselineId string Opaque token naming the accepted baseline. Present after solve and level (the baseline they accepted), after preview (the baseline it read), and after analyze(null) on a solved project with no pending edits. Absent otherwise, never null.
updates Mutation[] Tasks whose fields changed, in planning order, each with the changed fields only. With includeUnchanged it also holds unchanged tasks with their dates and duration.
cycles Cycle[] One entry per dependency cycle. [] when there are none.
conflicts Conflict[] Constraint and calendar conflicts. Cycles aren't repeated here.
notes Note[] Records left out of the plan, and fixes made in "repair" validation mode.
converged boolean false when the planner didn't settle on stable dates.
analytics Analytics Present only when the call's options request analytics.
overallocations Overallocation[] Present only when the project has assignments.
profile LoadProfile Present only on a preview called with the profile option.

A cycle, a conflict or converged: false isn't an error: the call still returns a result.

Note

The leveling result is a ScheduleResult with an added rounds field; read updates on it. See Project#level.

Mutation#

One entry of updates. It uses the TaskData field names, so it can be passed back as a TaskUpdate; kind and reason are ignored there.

Field Type Description
id Id Task id.
kind "task" | "summary" | "milestone" Task type as scheduled.
start_date DateValue New start. Present when changed.
end_date DateValue New end. Present when changed.
duration number New duration in the task's duration_unit. Present when changed.
leveling_delay number New leveling delay, elapsed time in the task's duration_unit. Present when changed.
pauses Pause[] The complete new list of pauses. Present when changed.
reason Reason Why the task moved. Present only with reasons: true.

A missing field means the value didn't change, not that it was cleared.

Reason#

Selected by kind:

kind Fields Meaning
"asap" linkId, sourceId Pushed by the predecessor sourceId through link linkId.
"alap" linkId, targetId Pulled by the successor targetId through link linkId.
"summary-translation" summaryId Moved as a block with its summary summaryId.
"constraint" none Placed by its own hard constraint.
"preferred" none Kept at, or snapped to, its own date.

Cycle#

Field Type Description
tasks Id[] Tasks in the cycle.
links Id[] Links that close the cycle.

Conflict#

Selected by kind:

kind Fields Meaning
"constraint-violation" task, constraint, violation, required, actual The task breaks its constraint (ConstraintType). violation is "earliest-start", "latest-start", "earliest-end" or "latest-end". required is the date the constraint asks for, actual the scheduled one.
"calendar-non-working" task, proposed, snapped The task's proposed date fell in non-working time and was moved to snapped.

required, actual, proposed and snapped are DateValues.

Note#

Selected by kind:

kind Fields Meaning
"dropped-link" link, reason The link was left out of the plan; reason is a message.
"dropped-task" task, reason The task was left out of the plan.
"dropped-assignment" assignment, reason The assignment was left out of the plan.
"repaired" path, message A fix made in "repair" validation mode; path points at the fixed input field.

Analytics#

Field Type Description
status "available" | "invalid" "invalid" when cycles prevent the analysis; the other fields are then absent.
criticalPath { tasks: Id[]; links: Id[] } Critical task ids in planning order, and the links that drive them with zero slack. Present when criticalPath was requested.
slack { task: Id; total: number; free: number }[] Total and free slack per task, in config.duration_unit. Present when slack was requested.

For how slack and the critical path are computed, see Critical path and slack.

Used by#

Example#

A solve result with reasons: true on a project with one link and two assigned tasks:

{
  baselineId: "1-ed3638c479bf1963",
  conflicts: [],
  converged: true,
  cycles: [],
  notes: [],
  overallocations: [],
  updates: [
    {
      end_date: "2026-08-13 08:00",
      id: 2,
      kind: "task",
      reason: { kind: "asap", linkId: 1, sourceId: 1 },
      start_date: "2026-08-12 08:00",
    },
  ],
}