Workspace

Workspace is a directory with LikeC4 source files.
When parsed, these files are "merged" into a single architecture model.
You are free to organize the workspace as you want.

Example

Assume we have the following workspace:

service1.c4
service2.c4

amazon.c4

landscape.c4

specs.c4

This file defines the specification:

specification {
  element actor {
    style {
      shape person
    }
  }
  element system
  element service
}

Extend element

extend is a way to enrich the model and define nested elements in a separate file.

For instance, we don't want to mess up the landscape.c4 file with the internals of the cloud.
In a separate cloud/service1.c4 file we define cloud.service1:

cloud/service1.c4

model {
  // cloud is defined in landscape.c4
  extend cloud {
    // here we define cloud.service1
    service1 = service 'Service 1'
  }
}

The element extension inherits the scope of the target (or better say parent).
For example, cloud/service2.c4 file:

cloud/service2.c4

model {
  // cloud is defined in landscape.c4
  extend cloud {
    // define cloud.service2
    service2 = service 'Some Service 2' {
 
      -> service1 'delegates some work' // ✅ service1 is known inside 'cloud', 
                                        //    and resolved even defined in another file 
    }
  }
 
  // service2 unique inside the file
  service2 -> service1       // ⛔️ Error: service1 not found
                             //    as can't be resolved from this file
 
  service2 -> cloud.service1 // ✅ OK: Resolved by fully qualified name
}

The target element must be referenced by a fully qualified name.

model {
  extend rds        // ⛔️ Error: rds not found in the global scope
  extend amazon.rds // ✅ Resolved by fully qualified name
}

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