TRAM

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CLI Generators ​

Tram provides some generators from the cli. Generators in Tram differ from generators in most other frameworks because they do not directly generate the requested code.

Instead Tram generators create runtimes. A runtime is a namespace that isn't in source control that lives at /src/main/dev/runtimes.

These runtimes contain two things: a blueprint data structure representing the changes to make in your project, and a comment block with an invocation of a tram function that will write those changes to your project. The tram function to write changes will overwrite previous changes.

The rationale for this workflow is that it can be hard to get the CLI command correct in one go. Rather than rewriting it, you can modify the blueprint, which is more verbose and easier to understand and then modify those changes without typing everything again.

TODO: add a flag to generators for "immediate mode" that will immediately write the changes. enable by default?

Migration generators ​

These generators can be invoked to create runtimesfor data migrations. The CLI syntax looks like this:

tram generate:model <attributes>

The attribute syntax looks like this:

[modifiers][column-name]:[column-type]=[default value]

The only required field is column-name, which will default to TEXT

Modifiers ​

The two supported modifiers are
  • ! for required fields
  • ^ for unique fields

Column Type ​

Postgres column types are supported, see tram.generators.blueprint/PostgresType for a full list. If omitted this will default to :text.

Default Value ​

Default values can either be literals (which will be parsed from strings into the matching data type from column-type) or they can be postgres functions. Function default values are indicated with the prefix fn/, eg. created-at:timestamptz=fn/now.

References (foreign keys) ​

Foreign key references do not follow this same syntax, they are declared by writing references(table-name). This will automatically be converted into a singularized version of the table name apended with -id. Nothing else is required for you to write these.

Examples ​

Here are some examples of attributes and how they are parsed:

clojure
"first-name"
;; =>
{:name "first_name"
 :type :text}

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

"!^email:citext"
{:name      "email"
 :type      :citext
 :required? true
 :unique?   true}

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

"!created-at:timestamptz=fn/now"
;; =>
{:name      "created_at"
 :type      :timestamptz
 :required? true
 :default   :fn/now}

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

"references(teams)"
;; =>
{:name      "team-id"
 :type      :integer
 :required? true}

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

"subscribed=yes"
;; =>
{:name    "subscribed"
 :type    :text
 :default "yes"}