====== Post Slack Message ======

===== Description =====

Posts a message on a Slack workspace. For example, this can be used to inform about the progress of a model that might take many hours to run.

===== Inputs =====

^ Name  ^ Type  ^ Description  ^
| Message  | [[String Type]]  | Message that will be posted on the slack channel. The message may include multiple lines of text.  |
| Channel  | [[String Type]]  | Slack channel where the message will be posted. Must start with a an "#". Ex: "#experimental". The channel must exist on the Slack workspace or the message will be ignored.  |
| Slack Webhook  | [[String Type]]  | URL of the corresponding Slack workspace webhook. This URL should be enabled for the Slack service before using it. Ex: "https://hooks.slack.com/services/xxxxxx/yyyyy/zzzzzz"  |

===== Optional Inputs =====

^ Name  ^ Type  ^ Description  ^ Default Value  ^
| Username  | [[String Type]]  | Username of the user posting the message. This username does not have to be a real user name. The name can include spaces and hyphens. Ex: "Dinamica EGO - Model".  | Dinamica EGO  |

===== Output =====

^ Name  ^ Type  ^ Description  ^
| Always True  | [[Boolean Value Type]]  | Used to facilitate chaining this submodel to other functors. Explicitly chaining functors simplify the definition of a custom execution order among them.  |

===== Notes =====

This submodel uses the [[https://cran.r-project.org/web/packages/curl/index.html|R package "curl"]] to post a message to an [[https://slack.com/|Slack channel]] specified.

In order to work with Slack, the submodels asks for the definition of an "incoming webhook" used to allow the communication between external applications and a Slack workspace. More information about how to create a webhook once you have created a slack channel can be found [[https://api.slack.com/custom-integrations/incoming-webhooks|here]].

As an additional constraints, the model using the submodel as part of its definition must be executed using a [[http://csr.ufmg.br/dinamica/dokuwiki/doku.php?id=reference_book:r_coupling#calculate_r_expression|custom R interpreter]], since the R script will automatically download and install the package "curl" if necessary. If downloading and installing the package is not possible, the submodel execution will have no effect.

===== Group =====

[[Functor List#Slack | Slack]]

===== Internal Name =====

PostSlackMessage