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Run Manager

The Run Manager gives you access to runs for your project. This allows you to read and update variables, call operations, etc. Additionally, the Run Manager gives you control over run creation depending on run states. Specifically, you can select run creation strategies (rules) for which runs end users of your project work with when they log in to your project.

There are many ways to create new runs, including the Epicenter.js Run Service and the RESFTful Run API. However, for some projects it makes more sense to pick up where the user left off, using an existing run. And in some projects, whether to create a new run or use an existing one is conditional, for example based on characteristics of the existing run or your own knowledge about the model. The Run Manager provides this level of control: your call to getRun(), rather than always returning a new run, returns a run based on the strategy you've specified. (Note that many of the Epicenter sample projects use a Run Service directly, because generally the sample projects are played in one end user session and don't care about run states or run strategies.)

Using the Run Manager to create and access runs

To use the Run Manager, instantiate it by passing in:

  • run: (required) Run object. Must contain:

    • account: Epicenter account id (Team ID for team projects, User ID for personal projects).
    • project: Epicenter project id.
    • model: The name of your primary model file. (See more on Writing your Model.)
    • scope: (optional) Scope object for the run, for example with value of the name of the group.
    • server: (optional) An object with one field, host. The value of host is the string, the URI of the Forio server. This is automatically set, but you can pass it explicitly if desired. It is most commonly used for clarity when you are hosting an Epicenter project on your own server.
    • files: (optional) If and only if you are using a Vensim model and you have additional data to pass in to your model, you can optionally pass a files object with the names of the files, for example: "files": {"data": "myExtraData.xls"}. (See more on Using External Data in Vensim.)
  • strategy: (optional) Run creation strategy for when to create a new run and when to reuse an end user's existing run. This is optional; by default, the Run Manager selects reuse-per-session, or reuse-last-initialized if you also pass in an initial operation. See below for more information on strategies.

  • strategyOptions: (optional) Additional options passed directly to the run creation strategy.

  • sessionKey: (optional) Name of browser cookie in which to store run information, including run id. Many conditional strategies, including the provided strategies, rely on this browser cookie to store the run id and help make the decision of whether to create a new run or use an existing one. The name of this cookie defaults to epicenter-scenario and can be set with the sessionKey parameter.

After instantiating a Run Manager, make a call to getRun() whenever you need to access a run for this end user. The contains the instantiated Run Service. The Run Service allows you to access variables, call operations, etc.


  var rm = new F.manager.RunManager({
      run: {
          account: 'acme-simulations',
          project: 'supply-chain-game',
          model: 'supply-chain-model.jl',
          server: { host: '' }
      strategy: 'reuse-never',
      sessionKey: 'epicenter-session'
      .then(function(run) {
          // the return value of getRun() is a run object
          var thisRunId =;
          // the also contains the instantiated Run Service,
          // so any Run Service method is valid here

Using the Run Manager to access and register strategies

The strategy for a Run Manager describes when to create a new run and when to reuse an end user's existing run. The Run Manager is responsible for passing a strategy everything it might need to determine the 'correct' run, that is, how to find the best existing run and how to decide when to create a new run.

There are several common strategies provided as part of Epicenter.js, which you can list by accessing F.manager.RunManager.strategies. You can also create your own strategies, and register them to use with Run Managers. See Run Manager Strategies for details.



Returns the run object for the 'correct' run. The correct run is defined by the strategy.

For example, if the strategy is reuse-never, the call to getRun() always returns a newly created run; if the strategy is reuse-per-session, getRun() returns the run currently referenced in the browser cookie, and if there is none, creates a new run. See Run Manager Strategies for more on strategies.


 rm.getRun().then(function (run) {
     // use the run object
     var thisRunId =;

     // use the Run Service object'runModel');

 rm.getRun(['sample_int']).then(function (run) {
    // an object whose fields are the name : value pairs of the variables passed to getRun()
    // the value of sample_int
  • variables: Array (Optional) The run object is populated with the provided model variables, if provided. Note: getRun() does not throw an error if you try to get a variable which doesn't exist. Instead, the variables list is empty, and any errors are logged to the console.

  • options: Object (Optional) Configuration options; passed on to RunService#create if the strategy does create a new run.


Returns the run object for a 'reset' run. The definition of a reset is defined by the strategy, but typically means forcing the creation of a new run. For example, reset() for the default strategies reuse-per-session and reuse-last-initialized both create new runs.


 rm.reset().then(function (run) {
     // use the (new) run object
     var thisRunId =;

     // use the Run Service object'runModel');