# Scriptform Manual
## Table of Contents
1. [Invocations](#invocations)
1. [Form config (JSON) files](#form_config)
1. [Field types](#field_types)
- [String](#field_types_string)
- [Integer](#field_types_integer)
- [Float](#field_types_float)
- [Date](#field_types_date)
- [Radio](#field_types_radio)
- [Select](#field_types_select)
- [Text](#field_types_text)
- [Password](#field_types_password)
- [File](#field_types_file)
1. [Output](#output)
1. [Callbacks](#callbacks)
- [Script callbacks]()
- [Validation]()
- [Field Values]()
- [Python callbacks]()
1. [Users](#users)
## Invocations
There are multiple ways of running ScriptForm. This chapter outlines the
various methods. They are listed in the order of least to most
pruduction-ready.
### Shell foreground
Sriptform can be run directly from the shell in the foreground. This is most
useful for testing and development.
Unless the paths to your scripts are absolute, you should run Scriptform from
the directory that contains the Form definition file.
### Behind Apache
Enable Apache modules mod_proxy and mod_proxy_http:
$ sudo a2enmod proxy
$ sudo a2enmod proxy_http
Configure:
Redirect permanent /scriptform /scriptform/
ProxyPass /scriptform/ http://localhost:8000/
ProxyPassReverse /scriptform/ http://localhost:8000/
Make sure the path ends in a slash! (That's what the redirect is for).
## Form config (JSON) files
Forms are defined in JSON format. They are referred to as *Form config*
files. A single JSON file may contain multiple forms. Scriptform will show them
on an overview page, and the user can select which form they want to fill out.
Structurally, they are made up of the following elements:
- **`title`**: Text to show at the top of each page. **Required**, **String**.
- **`forms`**: Dictionary where the key is the form id and the value is a
dictionary that is the definition for a single form. **Required**, **Dictionary**.
- **`title`**: Title for the form. **Required**, **String**.
- **`description`**: A description of the form. May include HTML tags. **Required**, **String**.
- **`submit_title`**: The text on the submit button of the form.
- **`script`**: The path to an executable script of binary that will be
called if the form is submitted. See also [[Callbacks]]. If this field is
omitted, Scriptform will instead call a python callable (function,
method) that's been registered. Scriptform will raise an error if the
script isn't found, if the script isn't executable or (if the `script`
tag is omitted) if no Python callback is registered to handle this form.
**String**.
- **`output`**: Determines how the output of the callback is handled. See
the *Output types* seciton.
- **`fields`**: List of fields in the form. Each field is a dictionary.
**Required**, **List of dictionaries**.
- **`name`**: The name of the field. This is what is passed as an
environment variable to the callback.
- **`title`**: The title for the field, shown just above the actual
field.
- **`type`**: Field type. Supported types are: *string*, *integer*,
*float*, *date*, *radio*, *select*, *text*, *password* and *file*.
For more information, see [Field types].
- **`required`**: Whether the field is required.
- **`...`**: Other options, which depend on the type of field.
- **`users`**: A dictionary of users where the key is the username and the
value is the plaintext password. This field is not required. **Dictionary**.
For example, here's a form config file that contains two forms:
{
"title": "Test server",
"forms": {
"import": {
"title": "Import data",
"description": "Import SQL into a database",
"submit_title": "Import",
"script": "job_import.sh",
"fields": [
{
"name": "target_db",
"title": "Database to import to",
"type": "select",
"options": [
["devtest", "Dev Test db"],
["prodtest", "Prod Test db"]
]
},
{
"name": "sql_file",
"title": "SQL file",
"type": "file"
}
]
},
"add_user": {
"title": "Add user",
"description": "Add a user to the htaccess file or change their password",
"submit_title": "Add user",
"script": "job_add_user.sh",
"fields": [
{
"name": "username",
"title": "Username",
"type": "string"
},
{
"name": "password1",
"title": "Password",
"type": "password"
},
{
"name": "password2",
"title": "Password (Repear)",
"type": "password"
}
]
}
}
}
## Field types
### String
The `string` field type presents the user with a single line input field.
The `string` field type supports the following additional options:
- **`minlen`**: The minimum allowed length for the field.
- **`maxlen`**: The maximum allowed length for the field.
### Integer
The `integer` field type presents the user with an input box in wich they may
enter an integer number. Depending on the browser's support for HTML5 forms,
the input field may have spin-buttons to increase and decrease the value.
The `integer` field type supports the following additional options:
- **`min`**: The minimum allowed value for the field.
- **`max`**: The maximum allowed value for the field.
### Float
The `float` field type presents the user with an input box in which they enter
a Real number (fractions).
The `float` field type supports the following additional options:
- **`min`**: The minimum allowed value for the field.
- **`max`**: The maximum allowed value for the field.
Please note that some real numbers cannot be represented exactly by a computer
and validation may thus be approximate. E.g. 0.499999999999999 will pass the
test for a maximum value of 0.5.
### Date
The `date` field type presents the user with an input box in which they can
enter a date. Depending on the browser's support for HTML5 forms, the input
field may have a pop-out calendar from which the user can select a date.
The date must be entered, and will be passed to the callback, in the form
YYYY-MM-DD.
The `date` field type supports the following additional options:
- **`min`**: The minimum allowed date (format: a string YYYY-MM-DD)
- **`max`**: The maximum allowed date (format: a string YYYY-MM-DD)
### Radio
### Select
### Text
The `text` field presents the user with a field in which they can enter
multi-lined text.
The `text` field type supports the following additional options:
- **`rows`**: The number of rows to make the input field
- **`cols`**: The number of cols to make the input filed.
- **`minlen`**: The minimum allowed length for the field.
- **`maxlen`**: The maximum allowed length for the field.
### Password
- **`minlen`**: The minimum allowed length for the field.
### File
The `file` field type presents the user with a field through which they can
upload a file. Uploaded files are streamed to temporary files by Scriptform,
after which the original field value is replaced with this temporary file name.
This allows users to upload large files.
The original file name of the uploaded file is stored in a new variable
'<field_name>__name'.
The `file` field type supports the following additional options:
- **`extensions`**: A list of extensions (minus leading dot) that are accepted
for file uploads. For example: `"extensions": ["csv", "tsv"]`
No additional validatikon is done on the file contents.
## Output
FIXME
If
its value is `escaped`, the output of the callback will have its HTML
entities escaped and will be wrapped in PRE elements. This is the
**default** option. If the value is `html`, the output will not be
escaped or wrapped in PRE tags, and can thus include HTML markup. If the
output is `raw`, the output of the script is streamed directly to the
client's browser. This allows you to output images, binary files, etc to
the client. The script must include the proper headers and body itself.
If the script's exit code is 0, the output of the script (stdout) is captured
and shown to the user in the browser.
If a script's exit code is not 0, it is assumed an error occured. Scriptform
will show the script's stderr output (in red) to the user instead of stdin.
FIXME:
If the form definition has a `script_raw` field, and its value is `true`,
Scriptform will pass the output of the script to the browser as-is. This allows
scripts to show images, stream a file download to the browser or even show
completely custom HTML output. The script's output must be a valid HTTP
response, including headers and a body. Examples of raw script output can be
found in the `examples/raw` directory.
## Callbacks
Callbacks are called after the form has been submitted and its values have been
validated. They are the actual implementations of the form's action.
There are two types of callbacks:
- Scripts
- Python callables (functions or methods)
### Validation
Fields of the form are validated by Scriptform before the script is called.
Exactly what is validated depends on the options specified in the Form
Definition. For more info on that, see the *Field Types* section of this
manual.
### Scripts
A script callback can be any kind of executable, written in any kind of
language. As long as it is executable, can read the environment and output
things to stdout, it can be used as a callback.
#### Field values
Field values are passed to the script in its environment. For instance, a form
field definition:
{
"name": "ip_address",
"title": "IP Address",
"type": "string"
}
becomes available in a shell script as:
echo $ip_address
Uploaded files are streamed to temporary files by Scriptform. The name of the
temporary file is then passed on as the field's value. For example, given the
following field definition:
{
"name": "csv_file",
"title": "CSV file to import",
"type": "file"
}
The contents of the file is available in a shell script as:
echo $csv_file # output: /tmp/tmp_scriptform_Xu72bK
ROWS=$(wc -l $csv_file)
echo "The CSV file has $(expr $ROWS - 1) rows"
These temporary files are automatically cleaned up after the script's exeuction
ends.
Examples of file uploads can be found in the `examples/simple` and
`examples/megacorp` directories.
### Python callbacks
or in a Python script as:
import os
print os.environ['ip_address']
## Users
ScriptForm supports basic htauth user authentication. Users can be defined, and
form access can be limited to certain users. Users are defined in the `users`
top-level field of the form configuration file. For example, in the following
form configuration file, there are two users. Only user `test2` is allowed to
view the form 'only_some_users'.
{
"title": "Authorization protected",
"users": {
"test": "2bb80d537b1da3e38bd30361aa855686bde0eacd7162fef6a25fe97bf527a25b",
"test2": "5e884898da28047151d0e56f8dc6292773603d0d6aabbdd62a11ef721d1542d8"
},
"forms": {
"only_some_users": {
"title": "Only some users",
"description": "You should only see this if you're user 'test2'",
"submit_title": "Do nothing",
"script": "job_do_nothing.sh",
"allowed_users": ["test2"],
"fields": []
}
}
}
Passwords are unsalted SHA256 hashed passwords. To generate one, you can use
the `--generate-pw` option of Scriptform. This will ask you twice for a
plaintext password and return the hash that can be used in the `users` element.
$ ./scriptform.py --generate-pw
Password:
Repeat password:
ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad
Form definitions may specify which users are allowed to view, access and submit
the form. This is specified by a `allowed_users` field in the form definition,
as can be seen in the previous form configuration example. Multiple users may
be specified.
### Security considerations
- Passwords have no salt. This makes them slightly easier to bruteforce en-mass.
- Scriptform does not natively support secure HTTPS connections. This means
usernames and passwords are transmitted over the line in nearly plaintext. If
you wish to prevent this, you should put Scriptform behind a proxy that
*does* support Scriptform, such as Apache. For more information on that, see
the "Invocations" chapter.