<html>
<head>
<title>Our admins and users</title>
</head>
{# This is a short example to give you a quick overview of pongo2's syntax. #}
{% macro user_details(user, is_admin=false) %}
<div class="user_item">
<!-- Let's indicate a user's good karma -->
<h2 {% if (user.karma>= 40) || (user.karma > calc_avg_karma(userlist)+5) %} class="karma-good"{% endif %}>
<!-- This will call user.String() automatically if available: -->
{{ user }}
</h2>
<!-- Will print a human-readable time duration like "3 weeks ago" -->
<p>This user registered {{ user.register_date|naturaltime }}.</p>
<!-- Let's allow the users to write down their biography using markdown;
we will only show the first 15 words as a preview -->
<p>The user's biography:</p>
<p>
{{ user.biography|markdown|truncatewords_html:15 }}
<a href="/user/{{ user.id }}/">read more</a>
</p>
{% if is_admin %}
<p>This user is an admin!</p>
{% endif %}
</div>
{% endmacro %}
<body>
<!-- Make use of the macro defined above to avoid repetitive HTML code
since we want to use the same code for admins AND members -->
<h1>Our admins</h1>
{% for admin in adminlist %} {{ user_details(admin, true) }} {% endfor %}
<h1>Our members</h1>
{% for user in userlist %} {{ user_details(user) }} {% endfor %}
</body>
</html>
Documentation
Getting Started - Installation, basic usage, and first steps
Template Syntax - Variables, expressions, operators, and comments
date / time: The date and time filter are taking the Golang specific time- and date-format (not Django's one) currently. Take a look on the format here.
stringformat: stringformat does not take Python's string format syntax as a parameter, instead it takes Go's. Essentially {{ 3.14|stringformat:"pi is %.2f" }} is fmt.Sprintf("pi is %.2f", 3.14).
escape / force_escape: Unlike Django's behaviour, the escape-filter is applied immediately. Therefore there is no need for a force_escape-filter yet.
Tags
for: All the forloop fields (like forloop.counter) are written with a capital letter at the beginning. For example, the counter can be accessed by forloop.Counter and the parentloop by forloop.Parentloop.
now: takes Go's time format (see date and time-filter).
Misc
not in-operator: You can check whether a map/struct/string contains a key/field/substring by using the in-operator (or the negation of it):
{% if key in map %}Key is in map{% else %}Key not in map{% endif %} or {% if !(key in map) %}Key is NOT in map{% else %}Key is in map{% endif %}.
Add-ons, libraries and helpers
Official
pongo2-addons - Official additional filters/tags for pongo2 (for example a markdown-filter). They are in their own repository because they're relying on 3rd-party-libraries.
Please see the documentation for a full list of provided API methods.
A tiny example (template string)
// Compile the template first (i. e. creating the AST)
tpl, err := pongo2.FromString("Hello {{ name|capfirst }}!")
if err != nil {
panic(err)
}
// Now you can render the template with the given
// pongo2.Context how often you want to.
out, err := tpl.Execute(pongo2.Context{"name": "florian"})
if err != nil {
panic(err)
}
fmt.Println(out) // Output: Hello Florian!
Example server-usage (template file)
package main
import (
"github.com/flosch/pongo2/v7"
"net/http"
)
// Pre-compiling the templates at application startup using the
// little Must()-helper function (Must() will panic if FromFile()
// or FromString() will return with an error - that's it).
// It's faster to pre-compile it anywhere at startup and only
// execute the template later.
var tplExample = pongo2.Must(pongo2.FromFile("example.html"))
func examplePage(w http.ResponseWriter, r *http.Request) {
// Execute the template per HTTP request
err := tplExample.ExecuteWriter(pongo2.Context{"query": r.FormValue("query")}, w)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
}
}
func main() {
http.HandleFunc("/", examplePage)
http.ListenAndServe(":8080", nil)
}
