lib/popcorn: add documentation for pop_templates

Signed-off-by: Alexandre Terrasa <alexandre@moz-code.org>

diff --git a/lib/popcorn/pop_templates.nit b/lib/popcorn/pop_templates.nit
index 802dd4b..f76c1e5 100644 (file)
--- a/lib/popcorn/pop_templates.nit
+++ b/lib/popcorn/pop_templates.nit
@@ -14,6 +14,72 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Template rendering for popcorn
+#
+# ## Basic templates
+#
+# Use TemplateString to render really basic templates that just need macro
+# replacements.
+#
+# Example:
+# ~~~nit
+# class TemplateStringHandler
+#      super Handler
+#
+#      redef fun get(req, res) do
+#              # Values to add in the template
+#              var values = new HashMap[String, String]
+#              values["USER"] = "Morriar"
+#              values["MYSITE"] = "My super website"
+#
+#              # Render it with a shortcut
+#              res.template_string("""
+#                      <h1>Hello %USER%!</h1>
+#                      <p>Welcome to %MYSITE%.</p>
+#              """, values)
+#      end
+# end
+# ~~~
+#
+# For larger templates, you can also use external files (makes your Nit code cleaner):
+# ~~~nit
+# class TemplateFileHandler
+#      super Handler
+#
+#      redef fun get(req, res) do
+#              # Values to add in the template
+#              var values = new HashMap[String, String]
+#              values["USER"] = "Morriar"
+#              values["MYSITE"] = "My super website"
+#
+#              # Render it from an external file
+#              res.template_file("example_template.tpl", values)
+#      end
+# end
+# ~~~
+#
+# ## Using pug templates
+#
+# Pug is a templating format provided by the external command `pug`.
+# For complex templates that need conditional or loop statements, pug can be a solution.
+#
+# See the pug syntax here: https://pugjs.org/api/getting-started.html
+#
+# ~~~nit
+# class PugFileHandler
+#      super Handler
+#
+#      redef fun get(req, res) do
+#              # Values to add in the template
+#              var json = new JsonObject
+#              json["user"] = "Morriar"
+#              json["mysite"] = "My super website"
+#
+#              # Render it from an external file
+#              res.pug_file("example_template.pug", json)
+#      end
+# end
+# ~~~
 module pop_templates
 
 import popcorn::pop_handlers