Glossary

The terms these pages use, in plain language. Terms are grouped by topic and sorted alphabetically within each group.

Modeling

BPMN (Business Process Model and Notation): The standard diagram language for business processes. You draw a process as a BPMN diagram (an XML file ending in .bpmn) and deploy it to TinyConductor. See BPMN coverage.

DMN (Decision Model and Notation): The standard for business decisions, usually written as decision tables. A process can call a DMN decision, and you can also evaluate one on its own. See DMN and FEEL.

Element: One shape in a BPMN diagram: a task, an event, a gateway or a sub-process. Also called a flow node.

FEEL (Friendly Enough Expression Language): The expression language of BPMN and DMN models, used for conditions, variable mappings and decision rules. For example amount > 1000.

Form: A user-task form, deployed with the process. The Tasks area of the console shows it to the person who works on the task.

Process definition: A deployed BPMN process. Each deployment of a changed diagram adds a new version of the definition; running instances keep the version they started on.

Running processes

Deployment: Uploading BPMN, DMN and form files to the engine, which checks them and makes them available to start.

Incident: A problem the engine cannot solve alone, for example a job that failed with no retries left or an expression that cannot be evaluated. The process instance waits at that point until someone fixes the cause and resolves the incident, for example in the console’s Operations area.

Job: A unit of work for a program outside the engine, created when a process instance reaches a service task (and a few other task types). Each job has a job type, such as send-invoice.

Job worker: Your program that asks the engine for jobs of a given type (activates them), does the work, and reports the job as completed or failed.

Message: Something that happens outside the engine and that a waiting process instance reacts to, matched by a message name and a correlation key (for example an order number).

Process instance: One run of a process definition, for example the handling of one order. It has its own variables and its own position (tokens) in the diagram.

Record: One saved fact about something the engine did, for example “a job was created” or “a user task was completed”. Records are written in order and never changed. The console, the audit log, the analytics views and process tests all read them.

Signal: A broadcast that every waiting process instance listening for that signal name reacts to.

Timer: A BPMN event that waits for a date, a duration or a repeating cycle, such as PT24H (24 hours).

Token: The marker that shows where a process instance currently is in the diagram. A parallel gateway can split one token into several.

User task: A task that a person does. People see, claim and complete user tasks in the console’s Tasks area. See Task authorization.

Variable: A named value that belongs to a process instance (or to part of it), such as orderTotal. Expressions, gateways and job workers read and write variables.

Deployment modes

Cell: In Cluster mode, one deployment: one PostgreSQL database and the engine nodes that share it. A cell serves many tenants; you run a second cell only to grow beyond one database. CONDUCTOR_CELL_ID names it, and the console’s Cell health area shows its state.

Cluster mode: The shared production mode for many tenants, on a PostgreSQL database you operate, with several engine nodes sharing the work. See Cluster mode.

Exporter: The part of the engine that copies saved changes into the tables that searches, history and reports read. Searches can therefore be a moment behind the engine. See How the engine runs your processes.

Embedded mode: The mode for process tests. The engine runs in memory, stores nothing, and uses a virtual clock. See Embedded mode.

Bundled mode: The durable production mode for one team: one container with the engine and PostgreSQL. See Bundled mode.

Node: One running engine process of a Cluster cell. Each node owns some of the cell’s partitions and forwards requests for the others to their owners.

Partition: One engine thread with the tenants placed on it. Each tenant has one home partition, usually shared with other tenants; a cell has 24 by default. See How the engine runs your processes.

Virtual clock: The clock of an Embedded engine. It stands still until your test moves it forward, so tests with timers run instantly and give the same result every time.

Access

Grant: A rule that gives an owner (a user, group, role or client) some permissions on a resource, such as one process or all processes.

Permission: Something a caller is allowed to do, named as an action such as instance:create, task:complete or history:read. * means every permission. Each API route requires one permission. See Identity and access.

Principal: Whoever makes a request: a person who signed in, or a program with a token (a service principal).

Role: A named set of permissions, such as the built-in operator or task-worker roles.

Tenant: A team or customer whose processes and data are kept apart from everyone else’s. Embedded mode has one tenant. Bundled mode has one, default, unless you configure more; Cluster mode has as many as you configure. See Tenant quotas.

Operations

TinyConductor Console: The web application for operators and task workers, at /console. Its Operations area shows deployments, process instances, incidents and the health of the engine; its Tasks area is where people work on user tasks. See TinyConductor Console.

Lag: How far a reader of the records (such as search, reporting or an exporter) is behind the engine. The console and the metrics show it, and an alarm fires when it grows too large. See Operations.