From 052f5581317f740aeda28af9902e8b0b822500a6 Mon Sep 17 00:00:00 2001
From: Stanislav Meduna <stano@meduna.org>
Date: Wed, 11 Jun 2025 12:14:02 +0200
Subject: [PATCH] Add support for custom request headers in online_image
 component (#8985)

---
 esphome/components/online_image/__init__.py      | 12 ++++++++++++
 esphome/components/online_image/online_image.cpp |  4 ++++
 esphome/components/online_image/online_image.h   |  7 +++++++
 tests/components/online_image/common.yaml        |  3 +++
 4 files changed, 26 insertions(+)

diff --git a/esphome/components/online_image/__init__.py b/esphome/components/online_image/__init__.py
index 7ef80ff92f..9380cf1b1b 100644
--- a/esphome/components/online_image/__init__.py
+++ b/esphome/components/online_image/__init__.py
@@ -2,6 +2,7 @@ import logging
 
 from esphome import automation
 import esphome.codegen as cg
+from esphome.components.const import CONF_REQUEST_HEADERS
 from esphome.components.http_request import CONF_HTTP_REQUEST_ID, HttpRequestComponent
 from esphome.components.image import (
     CONF_INVERT_ALPHA,
@@ -24,6 +25,7 @@ from esphome.const import (
     CONF_TYPE,
     CONF_URL,
 )
+from esphome.core import Lambda
 
 AUTO_LOAD = ["image"]
 DEPENDENCIES = ["display", "http_request"]
@@ -124,6 +126,9 @@ ONLINE_IMAGE_SCHEMA = (
             cv.GenerateID(CONF_HTTP_REQUEST_ID): cv.use_id(HttpRequestComponent),
             # Online Image specific options
             cv.Required(CONF_URL): cv.url,
+            cv.Optional(CONF_REQUEST_HEADERS): cv.All(
+                cv.Schema({cv.string: cv.templatable(cv.string)})
+            ),
             cv.Required(CONF_FORMAT): cv.one_of(*IMAGE_FORMATS, upper=True),
             cv.Optional(CONF_PLACEHOLDER): cv.use_id(Image_),
             cv.Optional(CONF_BUFFER_SIZE, default=65536): cv.int_range(256, 65536),
@@ -207,6 +212,13 @@ async def to_code(config):
     await cg.register_component(var, config)
     await cg.register_parented(var, config[CONF_HTTP_REQUEST_ID])
 
+    for key, value in config.get(CONF_REQUEST_HEADERS, {}).items():
+        if isinstance(value, Lambda):
+            template_ = await cg.templatable(value, [], cg.std_string)
+            cg.add(var.add_request_header(key, template_))
+        else:
+            cg.add(var.add_request_header(key, value))
+
     if placeholder_id := config.get(CONF_PLACEHOLDER):
         placeholder = await cg.get_variable(placeholder_id)
         cg.add(var.set_placeholder(placeholder))
diff --git a/esphome/components/online_image/online_image.cpp b/esphome/components/online_image/online_image.cpp
index 2b20b32772..8030bd0095 100644
--- a/esphome/components/online_image/online_image.cpp
+++ b/esphome/components/online_image/online_image.cpp
@@ -143,6 +143,10 @@ void OnlineImage::update() {
 
   headers.push_back(accept_header);
 
+  for (auto &header : this->request_headers_) {
+    headers.push_back(http_request::Header{header.first, header.second.value()});
+  }
+
   this->downloader_ = this->parent_->get(this->url_, headers, {ETAG_HEADER_NAME, LAST_MODIFIED_HEADER_NAME});
 
   if (this->downloader_ == nullptr) {
diff --git a/esphome/components/online_image/online_image.h b/esphome/components/online_image/online_image.h
index 920aee2796..6ed9c7956f 100644
--- a/esphome/components/online_image/online_image.h
+++ b/esphome/components/online_image/online_image.h
@@ -67,6 +67,11 @@ class OnlineImage : public PollingComponent,
     this->last_modified_ = "";
   }
 
+  /** Add the request header */
+  template<typename V> void add_request_header(const std::string &header, V value) {
+    this->request_headers_.push_back(std::pair<std::string, TemplatableValue<std::string> >(header, value));
+  }
+
   /**
    * @brief Set the image that needs to be shown as long as the downloaded image
    *  is not available.
@@ -153,6 +158,8 @@ class OnlineImage : public PollingComponent,
 
   std::string url_{""};
 
+  std::vector<std::pair<std::string, TemplatableValue<std::string> > > request_headers_;
+
   /** width requested on configuration, or 0 if non specified. */
   const int fixed_width_;
   /** height requested on configuration, or 0 if non specified. */
diff --git a/tests/components/online_image/common.yaml b/tests/components/online_image/common.yaml
index 25809930b5..422a24b540 100644
--- a/tests/components/online_image/common.yaml
+++ b/tests/components/online_image/common.yaml
@@ -11,6 +11,9 @@ online_image:
     format: PNG
     type: BINARY
     resize: 50x50
+    request_headers:
+      X-Test1: 'Test1'
+      X-Test2: !lambda 'static int x; return to_string(x++);'
     on_download_finished:
       lambda: |-
         if (cached) {