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Database functions

File

These functions can be used to work with files.

These functions can be used to work with files.

Function

Description

file::bucket()

Returns the bucket path from a file pointer

file::copy()

Copies the contents of a file

file::copy_if_not_exists()

Copies the contents of a file to a new file if the name is available

file::delete()

Deletes a file

file::exists()

Checks if a file already exists

file::get()

Loads a file

file::head()

Returns the metadata of a file

file::key()

Returns the key (the portion following the bucket) from a file pointer

file::list()

Returns a list of files inside a bucket

file::put()

Writes bytes to a file

file::put_if_not_exists()

Attempts to write bytes to a file

file::rename()

Renames a file

file::rename_if_not_exists()

Renames a file if the new name is not already in use

Available since: v3.0.0

API DEFINITION
file::bucket(file) -> string

The file::bucket function returns the name of the bucket in which a file is located.

/**[test]

[[test.results]]
value = "'my_bucket'"

[[test.results]]
value = "NONE"

[[test.results]]
value = "'my_bucket'"

*/
file::bucket(f"my_bucket:/file_name");

DEFINE PARAM $SOME_DATABASE_FILE VALUE f"my_bucket:/file_name";
file::bucket($SOME_DATABASE_FILE);
Output
'my_bucket'

The counterpart to this function is file::key, which returns the latter part of a file pointer.

The file::copy function copies the contents of a file to a new file, overwriting any existing file that has the same name as the new file.

API DEFINITION
file::copy(string)

Example of a file my_book.txt being copied to a new location lion_witch_wardrobe.txt:

/**[test]

[[test.results]]
error = ""The bucket 'my_bucket' does not exist""

*/

f"my_bucket:/my_book.txt".copy("lion_witch_wardrobe.txt");


The file::copy_if_not_exists function copies the contents of a file to a new file, returning an error if a file already exists that has the same name as that of the intended copy.

API DEFINITION
file::copy_if_not_exists(string)

Example of a file my_book.txt attempting to copy to a new location lion_witch_wardrobe.txt:

DEFINE BUCKET my_bucket BACKEND "memory";

f"my_bucket:/lion_witch_wardrobe.txt".put("Once there were four children whose names were Peter, Susan...");
f"my_bucket:/other_book.txt".put("Um meine Geschichte zu erzählen, muß ich weit vorn anfangen.");
f"my_bucket:/other_book.txt".copy_if_not_exists("lion_witch_wardrobe.txt");
Output
'Operation for bucket `my_bucket` failed: Object at location lion_witch_wardrobe.txt already exists:
Object already exists at that location: lion_witch_wardrobe.txt'


The file::delete function deletes a file.

API DEFINITION
file::delete(string)

Example of a file my_book.txt being deleted:

f"my_bucket:/my_book.txt".delete();


The file::exists function checks to see if a file exists at the path and file name indicated.

API DEFINITION
file::exists(string) -> bool

Example of an IF else STATEMENT used to check if a file exists before writing content to the location:

IF f"my_bucket:/my_book.txt".exists() {
    THROW "Whoops, already there!"
} ELSE {
    f"my_bucket:/my_book.txt".put("Some content")
};


The file::get function retrieves a file for use.

API DEFINITION
file::get(string) -> bytes

A retrieved file will display as bytes. If valid text, these can be cast into a string.

f"my_bucket:/my_book.txt".get();
<string>f"my_bucket:/my_book.txt".get();
Output
-------- Query --------

b"536F6D6520636F6E74656E74"

-------- Query --------

'Once there were four children whose names were Peter, Susan...'


The file::head function returns the metadata for a file.

API DEFINITION
file::head() -> object

If a file is found, the metadata will be returned as an object with the following fields:

  • `e_data` (`option`): the unique identifier for the file.

  • last_modified (datetime)

  • location (string)

  • size (int)

  • `version` (`option`)

An example of this function and its output:

f"my_bucket:/my_book.txt".head();
Output
{
	e_tag: '1',
	key: 'my_book.txt',
	last_modified: d'2025-03-26T06:29:18.988Z',
	size: 78,
	version: NONE
}


API DEFINITION
file::key(file) -> string

The file::key function returns the key of a file: the part of a file pointer following the bucket name.

/**[test]

[[test.results]]
value = "'/file_name'"

[[test.results]]
value = "NONE"

[[test.results]]
value = "'/file_name'"

*/
file::key(f"my_bucket:/file_name");

DEFINE PARAM $SOME_DATABASE_FILE VALUE f"my_bucket:/file_name";
file::key($SOME_DATABASE_FILE);
Output
'/file_name'

The counterpart to this function is file::bucket, which returns the bucket name of a file pointer.

API DEFINITION
file::list(string, $list_options: option<object>) -> array<object>

The file::list returns the metadata for the files inside a certain bucket. The output is an array of objects, each containing the following fields:

  • file: the pointer to the file.

  • size (int): the file size in bytes.

  • updated (datetime): the last time a change was made to the file.

/**[test]

[[test.results]]
value = "NONE"
[[test.results]]
value = "NONE"
[[test.results]]
value = "NONE"
[[test.results]]
value = "NONE"
[[test.results]]
value = "[{ file: f"my_bucket:/awesome_book", size: 19, updated: d'2025-10-07T01:13:20.226926Z' }, { file: f"my_bucket:/some_book", size: 39, updated: d'2025-10-07T01:13:20.227320Z' }]
"
*/

DEFINE BUCKET my_bucket BACKEND "memory";

f"my_bucket:/some_book".put("Once upon a time...");
f"my_bucket:/some_book".rename("awesome_book");
f"my_bucket:/some_book".put("In a hole in the ground lived a Hobbit.");
file::list("my_bucket");
Output
[
	{
		file: f"my_bucket:/awesome_book",
		size: 19,
		updated: d'2025-04-08T03:28:20.530511Z'
	},
	{
		file: f"my_bucket:/some_book",
		size: 39,
		updated: d'2025-04-08T03:28:20.530704Z'
	}
]

To modify the output, a second argument can be passed in that contains a single object with up to three fields:

  • limit (int): the maximum number of files to display.

  • start (string): displays files ordered after start.

  • prefix (string): displays files whose names begin with prefix.

Some examples of the function containing the second object and their responses:

file::list("my_bucket", { limit: 1 });
file::list("my_bucket", { limit: 0 });
Output
-------- Query --------
[
	{
		file: f"my_bucket:/awesome_book",
		size: 19,
		updated: d'2025-04-15T05:35:40.913221Z'
	}
]

-------- Query --------
[]
file::list("my_bucket", { prefix: "some" });
file::list("my_bucket", { prefix: "someBOOOEOEOK" });
Output
-------- Query --------
[
	{
		file: f"my_bucket:/some_book",
		size: 39,
		updated: d'2025-04-15T05:35:40.913554Z'
	}
]

-------- Query --------
[]
file::list("my_bucket", { start: "a" });
file::list("my_bucket", { start: "m" });
Output
-------- Query --------
[
	{
		file: f"my_bucket:/awesome_book",
		size: 19,
		updated: d'2025-04-15T05:55:41.973869Z'
	},
	{
		file: f"my_bucket:/some_book",
		size: 39,
		updated: d'2025-04-15T05:55:41.974370Z'
	}
]

-------- Query --------
[
	{
		file: f"my_bucket:/some_book",
		size: 39,
		updated: d'2025-04-15T05:55:41.974370Z'
	}
]
file::list("my_bucket", { prefix: "some", start: "a", limit: 1 });
Output
[
	{
		file: f"my_bucket:/some_book",
		size: 39,
		updated: d'2025-04-15T05:35:40.913554Z'
	}
]

The file::put function adds data into a file, overwriting any existing data.

API DEFINITION
file::put()

An example of this function followed by file::get() to display the contents:

/**[test]

[[test.results]]
value = "NONE"

[[test.results]]
value = "NONE"

[[test.results]]
value = "NONE"

[[test.results]]
value = ""Or were there? I don't quite remember.""

*/

DEFINE BUCKET my_bucket BACKEND "memory";

f"my_bucket:/my_book.txt".put("Once there were four children whose names were Peter, Susan...");
f"my_bucket:/my_book.txt".put("Or were there? I don't quite remember.");
<string>f"my_bucket:/my_book.txt".get();
Output
"Or were there? I don't quite remember."


The file::put function adds data into a file, unless a file of the same name already exists.

API DEFINITION
file::put_if_not_exists()

An example of this function followed by file::get() to display the contents:

/**[test]

[[test.results]]
value = "NONE"

[[test.results]]
value = "NONE"

[[test.results]]
value = "NONE"

[[test.results]]
value = "'Once there were four children whose names were Peter, Susan...'"

*/

DEFINE BUCKET my_bucket BACKEND "memory";

-- Creates file and adds data
f"my_bucket:/my_book.txt".put_if_not_exists("Once there were four children whose names were Peter, Susan...");
-- Does nothing
f"my_bucket:/my_book.txt".put_if_not_exists("Or were there? I don't quite remember.");
<string>f"my_bucket:/my_book.txt".get();
Output
'Once there were four children whose names were Peter, Susan...'


The file::rename function renames a file, overwriting any existing file that has the same name as the target name.

API DEFINITION
file::rename()

An example of a file being renamed over an existing file:

/**[test]

[[test.results]]
value = "NONE"

[[test.results]]
value = "NONE"

[[test.results]]
value = "NONE"

[[test.results]]
value = "NONE"

[[test.results]]
value = ""Or were there? I don't quite remember.""

*/


DEFINE BUCKET my_bucket BACKEND "memory";

f"my_bucket:/my_book.txt".put("Once there were four children whose names were Peter, Susan...");
f"my_bucket:/other_book.txt".put("Or were there? I don't quite remember.");
-- Rename to my_book.txt, overwriting existing file of the same name
f"my_bucket:/other_book.txt".rename("my_book.txt");
<string>f"my_bucket:/my_book.txt".get();
Output
"Or were there? I don't quite remember."


The file::rename_if_not_exists function renames a file, returning an error if a file already exists that has the same name as the target name.

API DEFINITION
file::rename_if_not_exists()
Output
-------- Query --------

'Operation for bucket `my_bucket` failed: Object at location my_book.txt already exists:
Object already exists at that location: my_book.txt'

-------- Query --------

'Once there were four children whose names were Peter, Susan...

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