.. index:: single: http_multipart .. _http_multipart/0:

.. rst-class:: right

object

http_multipart

Multipart helper predicates built on top of the normalized body and part terms provided by the http library.

| Availability: | logtalk_load(http_multipart(loader))

| Author: Paulo Moura | Version: 1:0:0 | Date: 2026-06-26

| Compilation flags: | static, context_switching_calls

| Imports: | public :ref:`http_text_helpers <http_text_helpers/0>` | Uses: | :ref:`http_core <http_core/0>` | :ref:`list <list/0>` | :ref:`type <type/0>`

| Remarks: | (none)

| Inherited public predicates: | (none)

.. contents:: :local: :backlinks: top

Public predicates

.. index:: body/3 .. _http_multipart/0::body/3:

body/3 ^^^^^^^^^^

Constructs a validated normalized multipart body term from a multipart media type atom and a list of multipart parts.

| Compilation flags: | static

| Template: | body(MediaType,Parts,Body) | Mode and number of proofs: | body(+atom,+list(compound),-compound) - one_or_error

| Exceptions: | MediaType is not a valid multipart media type atom: | domain_error(http_multipart_media_type,MediaType) | Parts is not a valid list of normalized multipart parts: | domain_error(http_multipart_parts,Parts)

---

.. index:: is_body/1 .. _http_multipart/0::is_body/1:

is_body/1 ^^^^^^^^^^^^^

True when the argument is a valid normalized multipart body term.

| Compilation flags: | static

| Template: | is_body(Body) | Mode and number of proofs: | is_body(@term) - zero_or_one

---

.. index:: parse/4 .. _http_multipart/0::parse/4:

parse/4 ^^^^^^^^^^^

Parses a multipart body from a source term by delegating to the underlying http_core::parse_body/4 predicate after validating the media type.

| Compilation flags: | static

| Template: | parse(Source,MediaType,Options,Body) | Mode and number of proofs: | parse(++compound,+atom,+list,-compound) - one_or_error

| Exceptions: | MediaType is not a valid multipart media type atom: | domain_error(http_multipart_media_type,MediaType) | Source is a variable: | instantiation_error | Source is neither a variable nor a valid HTTP source term: | domain_error(http_source,Source) | Options is not a valid HTTP body options list: | domain_error(http_body_options,Options) | No registered HTTP body codec exists for MediaType when codec-based decoding is required: | existence_error(http_body_codec,MediaType) | The parsed body is not a valid normalized multipart body term: | domain_error(http_multipart_body,Body)

---

.. index:: generate/3 .. _http_multipart/0::generate/3:

generate/3 ^^^^^^^^^^^^^^

Generates a multipart body to a sink term by delegating to the underlying http_core::generate_body/3 predicate after validating the multipart body term.

| Compilation flags: | static

| Template: | generate(Sink,Body,Options) | Mode and number of proofs: | generate(++compound,+compound,+list) - one_or_error

| Exceptions: | Body is not a valid normalized multipart body term: | domain_error(http_multipart_body,Body) | Sink is a variable: | instantiation_error | Sink is neither a variable nor a valid HTTP sink term: | domain_error(http_sink,Sink) | Options is not a valid HTTP body options list: | domain_error(http_body_options,Options) | No registered HTTP body codec exists for the body media type when codec-based encoding is required: | existence_error(http_body_codec,MediaType)

---

.. index:: media_type/2 .. _http_multipart/0::media_type/2:

media_type/2 ^^^^^^^^^^^^^^^^

Returns the media type atom of a validated multipart body term.

| Compilation flags: | static

| Template: | media_type(Body,MediaType) | Mode and number of proofs: | media_type(+compound,-atom) - one_or_error

| Exceptions: | Body is not a valid normalized multipart body term: | domain_error(http_multipart_body,Body)

---

.. index:: parts/2 .. _http_multipart/0::parts/2:

parts/2 ^^^^^^^^^^^

Returns the list of multipart part terms of a validated multipart body term.

| Compilation flags: | static

| Template: | parts(Body,Parts) | Mode and number of proofs: | parts(+compound,-list(compound)) - one_or_error

| Exceptions: | Body is not a valid normalized multipart body term: | domain_error(http_multipart_body,Body)

---

.. index:: fields/2 .. _http_multipart/0::fields/2:

fields/2 ^^^^^^^^^^^^

Returns the list of form-data field(Name, Value, Parameters) descriptors found in a validated multipart/form-data body, preserving part order.

| Compilation flags: | static

| Template: | fields(Body,Fields) | Mode and number of proofs: | fields(+compound,-list(compound)) - one_or_error

| Exceptions: | Body is not a valid normalized multipart/form-data body term: | domain_error(http_multipart_form_data_body,Body)

---

.. index:: files/2 .. _http_multipart/0::files/2:

files/2 ^^^^^^^^^^^

Returns the list of form-data file(Name, Filename, MediaType, Payload, Parameters) descriptors found in a validated multipart/form-data body, preserving part order.

| Compilation flags: | static

| Template: | files(Body,Files) | Mode and number of proofs: | files(+compound,-list(compound)) - one_or_error

| Exceptions: | Body is not a valid normalized multipart/form-data body term: | domain_error(http_multipart_form_data_body,Body)

---

.. index:: part/4 .. _http_multipart/0::part/4:

part/4 ^^^^^^^^^^

Constructs a validated normalized multipart part term from headers, body, and properties.

| Compilation flags: | static

| Template: | part(Headers,Body,Properties,Part) | Mode and number of proofs: | part(+list(compound),+compound,+list(compound),-compound) - one_or_error

| Exceptions: | The given headers, body, and properties do not form a valid normalized multipart part term: | domain_error(http_multipart_part,Part)

---

.. index:: is_part/1 .. _http_multipart/0::is_part/1:

is_part/1 ^^^^^^^^^^^^^

True when the argument is a valid normalized multipart part term.

| Compilation flags: | static

| Template: | is_part(Part) | Mode and number of proofs: | is_part(@term) - zero_or_one

---

.. index:: part_headers/2 .. _http_multipart/0::part_headers/2:

part_headers/2 ^^^^^^^^^^^^^^^^^^

Returns the headers of a validated multipart part term.

| Compilation flags: | static

| Template: | part_headers(Part,Headers) | Mode and number of proofs: | part_headers(+compound,-list(compound)) - one_or_error

| Exceptions: | Part is not a valid normalized multipart part term: | domain_error(http_multipart_part,Part)

---

.. index:: part_body/2 .. _http_multipart/0::part_body/2:

part_body/2 ^^^^^^^^^^^^^^^

Returns the body of a validated multipart part term.

| Compilation flags: | static

| Template: | part_body(Part,Body) | Mode and number of proofs: | part_body(+compound,-compound) - one_or_error

| Exceptions: | Part is not a valid normalized multipart part term: | domain_error(http_multipart_part,Part)

---

.. index:: part_properties/2 .. _http_multipart/0::part_properties/2:

part_properties/2 ^^^^^^^^^^^^^^^^^^^^^

Returns the properties of a validated multipart part term.

| Compilation flags: | static

| Template: | part_properties(Part,Properties) | Mode and number of proofs: | part_properties(+compound,-list(compound)) - one_or_error

| Exceptions: | Part is not a valid normalized multipart part term: | domain_error(http_multipart_part,Part)

---

.. index:: field/4 .. _http_multipart/0::field/4:

field/4 ^^^^^^^^^^^

True when the validated multipart part is a textual form-data field part, returning its field name, text value, and additional disposition parameters.

| Compilation flags: | static

| Template: | field(Part,Name,Value,Parameters) | Mode and number of proofs: | field(+compound,-atom,-term,-list(compound)) - zero_or_one

---

.. index:: file/6 .. _http_multipart/0::file/6:

file/6 ^^^^^^^^^^

True when the validated multipart part is a form-data file part, returning its field name, filename, media type, payload term, and additional disposition parameters.

| Compilation flags: | static

| Template: | file(Part,Name,Filename,MediaType,Payload,Parameters) | Mode and number of proofs: | file(+compound,-atom,-atom,-atom,-compound,-list(compound)) - zero_or_one

---

.. index:: field_part/4 .. _http_multipart/0::field_part/4:

field_part/4 ^^^^^^^^^^^^^^^^

Constructs a normalized multipart part for a textual form-data field using a content-disposition header, a text/plain body, and additional disposition parameters.

| Compilation flags: | static

| Template: | field_part(Name,Value,Parameters,Part) | Mode and number of proofs: | field_part(+atom,+term,+list(compound),-compound) - one_or_error

| Exceptions: | Name is not a valid form-data field name: | domain_error(http_multipart_form_data_parameter_name,Name) | Parameters is not a valid list of additional form-data disposition parameters: | domain_error(http_multipart_form_data_parameters,Parameters) | A form-data disposition parameter is invalid for a textual field part: | domain_error(http_multipart_form_data_parameter,Parameter)

---

.. index:: file_part/6 .. _http_multipart/0::file_part/6:

file_part/6 ^^^^^^^^^^^^^^^

Constructs a normalized multipart part for a form-data file using a content-disposition header, the given media type and payload, and additional disposition parameters.

| Compilation flags: | static

| Template: | file_part(Name,Filename,MediaType,Payload,Parameters,Part) | Mode and number of proofs: | file_part(+atom,+atom,+atom,+compound,+list(compound),-compound) - one_or_error

| Exceptions: | Name is not a valid form-data field name: | domain_error(http_multipart_form_data_parameter_name,Name) | Filename is not a valid form-data filename value: | domain_error(http_multipart_form_data_parameter_value,Filename) | Parameters is not a valid list of additional form-data disposition parameters: | domain_error(http_multipart_form_data_parameters,Parameters) | A form-data disposition parameter is invalid for a file part: | domain_error(http_multipart_form_data_parameter,Parameter)

---

.. index:: form_data_body/2 .. _http_multipart/0::form_data_body/2:

form_data_body/2 ^^^^^^^^^^^^^^^^^^^^

Constructs a multipart/form-data body from an ordered list of field(Name, Value, Parameters) and file(Name, Filename, MediaType, Payload, Parameters) descriptors.

| Compilation flags: | static

| Template: | form_data_body(Items,Body) | Mode and number of proofs: | form_data_body(+list(compound),-compound) - one_or_error

| Exceptions: | Items is not a valid list of form-data field or file descriptors: | domain_error(http_multipart_form_data_items,Items)

---

Protected predicates

(no local declarations; see entity ancestors if any)

Private predicates

(no local declarations; see entity ancestors if any)

Operators

(none)