.. index:: single: http_message_helpers .. _http_message_helpers/0:

.. rst-class:: right

category

http_message_helpers

Internal shared helpers for HTTP transport persistence rules, connection token normalization, and chunk-size line parsing.

| Availability: | logtalk_load(http_core(loader))

| Author: Paulo Moura | Version: 1:0:0 | Date: 2026-05-23

| Compilation flags: | static

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

| Remarks: | (none)

| Inherited public predicates: | (none)

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

Public predicates

(no local declarations; see entity ancestors if any)

Protected predicates

.. index:: connection_persistent/2 .. _http_message_helpers/0::connection_persistent/2:

connection_persistent/2 ^^^^^^^^^^^^^^^^^^^^^^^^^^^

Succeeds when a request-response exchange can continue on the same connection according to HTTP persistence semantics.

| Compilation flags: | static

| Template: | connection_persistent(Request,Response) | Mode and number of proofs: | connection_persistent(+compound,+compound) - zero_or_one

---

.. index:: request_persistent/1 .. _http_message_helpers/0::request_persistent/1:

request_persistent/1 ^^^^^^^^^^^^^^^^^^^^^^^^

Succeeds when a normalized HTTP request keeps the connection persistent.

| Compilation flags: | static

| Template: | request_persistent(Request) | Mode and number of proofs: | request_persistent(+compound) - zero_or_one

---

.. index:: response_persistent/1 .. _http_message_helpers/0::response_persistent/1:

response_persistent/1 ^^^^^^^^^^^^^^^^^^^^^^^^^

Succeeds when a normalized HTTP response keeps the connection persistent.

| Compilation flags: | static

| Template: | response_persistent(Response) | Mode and number of proofs: | response_persistent(+compound) - zero_or_one

---

.. index:: version_persistent_by_default/1 .. _http_message_helpers/0::version_persistent_by_default/1:

version_persistent_by_default/1 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Succeeds when the given HTTP version uses persistent connections by default.

| Compilation flags: | static

| Template: | version_persistent_by_default(Version) | Mode and number of proofs: | version_persistent_by_default(+compound) - zero_or_one

---

.. index:: message_has_connection_token/2 .. _http_message_helpers/0::message_has_connection_token/2:

message_has_connection_token/2 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Succeeds when a normalized HTTP message exposes the given normalized Connection token through either headers or derived properties.

| Compilation flags: | static

| Template: | message_has_connection_token(Message,Token) | Mode and number of proofs: | message_has_connection_token(+compound,+atom) - zero_or_one

---

.. index:: message_connection_tokens/2 .. _http_message_helpers/0::message_connection_tokens/2:

message_connection_tokens/2 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns the de-duplicated normalized Connection tokens exposed by a normalized HTTP message.

| Compilation flags: | static

| Template: | message_connection_tokens(Message,Tokens) | Mode and number of proofs: | message_connection_tokens(+compound,-list(atom)) - one

---

.. index:: message_header_values/3 .. _http_message_helpers/0::message_header_values/3:

message_header_values/3 ^^^^^^^^^^^^^^^^^^^^^^^^^^^

Returns the stored header values for the given header name in message order.

| Compilation flags: | static

| Template: | message_header_values(Message,Name,Values) | Mode and number of proofs: | message_header_values(+compound,+atom,-list) - one

---

.. index:: chunk_size_line_size/2 .. _http_message_helpers/0::chunk_size_line_size/2:

chunk_size_line_size/2 ^^^^^^^^^^^^^^^^^^^^^^^^^^

Parses a chunk-size line into its hexadecimal size, ignoring optional whitespace and chunk extensions.

| Compilation flags: | static

| Template: | chunk_size_line_size(LineBytes,Size) | Mode and number of proofs: | chunk_size_line_size(+list(integer),-integer) - one

---

Private predicates

(no local declarations; see entity ancestors if any)

Operators

(none)