hurl/docs/templates.md

Templates

Variables

In Hurl file, you can generate value using two curly braces, i.e {{my_variable}}. For instance, if you want to reuse a value from an HTTP response in the next entries, you can capture this value in a variable and reuse it in a template.

GET https://example.org

HTTP/1.1 200
[Captures]
csrf_token: xpath "string(//meta[@name='_csrf_token']/@content)"

# Do the login !
POST https://acmecorp.net/login?user=toto&password=1234
X-CSRF-TOKEN: {{csrf_token}}

HTTP/1.1 302

In this example, we capture the value of the CSRF token from the body of the first response, and inject it as a header in the next POST request.

GET https://example.org/api/index
HTTP/* 200
[Captures]
index: body

GET https://example.org/api/status
HTTP/* 200
[Asserts]
jsonpath "$.errors[{{index}}].id" == "error"

In this second example, we capture the body in a variable index, and reuse this value in the query jsonpath "$.errors[{{index}}].id".

Types

Variables are typed, and can be either string, bool, number, null or collections. Depending on the variable type, templates can be rendered differently. Let's say we have captured an integer value into a variable named count:

GET https://sample/counter
HTTP/* 200
[Captures]
count: jsonpath "$.results[0]"

The following entry:

GET https://sample/counter/{{count}} 
HTTP/* 200
[Asserts]
jsonpath "$.id" == "{{count}}"

will be rendered at runtime to:

GET https://sample/counter/458 
HTTP/* 200
[Asserts]
jsonpath "$.id" == "458"

resulting in a comparison between the JSONPath expression and a string value.

On the other hand, the following assert:

GET https://sample/counter/{{count}} 
HTTP/* 200
[Asserts]
jsonpath "$.index" == {{count}}

will be rendered at runtime to:

GET https://sample/counter/458 
HTTP/* 200
[Asserts]
jsonpath "$.index" == 458

resulting in a comparison between the JSONPath expression and an integer value.

So if you want to use typed values (in asserts for instances), you can use {{my_var}}. If you're interested in the string representation of a variable, you can surround the variable with double quotes , as in "{{my_var}}".

When there is no possible ambiguities, like using a variable in an URL, or in a header, you can omit the double quotes. The value will always be rendered as a string.

Injecting Variables

Variables can also be injected in a Hurl file:

• by using --variable option
• by using --variables-file option
• by defining environment variables, for instance HURL_foo=bar

Lets' see how to inject variables, given this test.hurl:

GET https://{{host}}/{{id}}/status
HTTP/1.1 304

GET https://{{host}}/health
HTTP/1.1 200

variable option

Variable can be defined with command line option:

$ hurl --variable host=example.net --variable id=1234 test.hurl

variables-file option

We can also define all injected variables in a file:

$ hurl --variables-files vars.env test.hurl

where vars.env is

host=example.net
id=1234

Environment variable

Finally, we can use environment variables in the form of HURL_name=value:

$ export HURL_host=example.net
$ export HURL_id=1234 
$ hurl test.hurl

Templating Body

Using templates with JSON body or XML body is not currently supported in Hurl. Besides, you can use templates in multiline string body with variables to send a JSON or XML body:

PUT https://example.org/api/hits
Content-Type: application/json
```
{
    "key0": "{{a_string}}",
    "key1": {{a_bool}},
    "key2": {{a_null}},
    "key3": {{a_number}}
}
```

Variables can be initialized via command line:

$ hurl --variable a_string=apple --variable a_bool=true --variable a_null=null --variable a_number=42 test.hurl

Resulting in a PUT request with the following JSON body:

{
    "key0": "apple",
    "key1": true,
    "key2": null,
    "key3": 42
}