DomPDF remote images blocked/broken due to missing user agent

Similar problem with OVH hosting. It is required the user-agent. All the files exists and are accesible vía browser but DomPDF can't access them.

Drupal LOG:

Error generating document: 
Failed to generate PDF: 

file_get_contents(https://<DOMAIN>/sites/default/files/css/css_Swr_hRAtW0jSHWbyenAiqMecy20dpgniBv9v4K6Y6zY.css): Failed to open stream: HTTP request failed! HTTP/1.1 403 Forbidden , Unable to load css file https://<DOMAIN>/sites/default/files/css/css_Swr_hRAtW0jSHWbyenAiqMecy20dpgniBv9v4K6Y6zY.css,

file_get_contents(https://<DOMAIN>/sites/default/files/pdf_imagenes/Cabecera_PDF_SC_SUMADOS.png): Failed to open stream: HTTP request failed! HTTP/1.1 403 Forbidden , Image not found /sites/default/files/pdf_imagenes/Cabecera_PDF_SC_SUMADOS.png,

file_get_contents(https://<DOMAIN>/system/files/webform/<IMAGE_PATH>): Failed to open stream: HTTP request failed! HTTP/1.1 403 Forbidden , Image not found https://<DOMAIN>/system/files/webform/<IMAGE_PATH>

Hosting LOG:

CSS:

[Wed Mar 08 16:23:37 2023] [error] [client <IP_ADDRES>] ModSecurity: Access denied with code 403 (phase 2). Operator EQ matched 0 at REQUEST_HEADERS. [file "/usr/local/apache2/conf/modsecurity/base_rules/modsecurity_crs_21_protocol_anomalies.conf"] [line "65"] [id "960009"] [rev "2.1.1"] [msg "Request Missing a User Agent Header"] [severity "NOTICE"] [tag "PROTOCOL_VIOLATION/MISSING_HEADER_UA"] [tag "WASCTC/WASC-21"] [tag "OWASP_TOP_10/A7"] [tag "PCI/6.5.10"] [hostname "<DOMAIN>"] [uri "/sites/default/files/css/css_Swr_hRAtW0jSHWbyenAiqMecy20dpgniBv9v4K6Y6zY.css"] [unique_id "ZAioeYUtHj9div7cW2O1CgAAAEo"]

IMAGE:

[Wed Mar 08 16:23:37 2023] [error] [client <IP_ADDRES>] ModSecurity: Access denied with code 403 (phase 2). Operator EQ matched 0 at REQUEST_HEADERS. [file "/usr/local/apache2/conf/modsecurity/base_rules/modsecurity_crs_21_protocol_anomalies.conf"] [line "65"] [id "960009"] [rev "2.1.1"] [msg "Request Missing a User Agent Header"] [severity "NOTICE"] [tag "PROTOCOL_VIOLATION/MISSING_HEADER_UA"] [tag "WASCTC/WASC-21"] [tag "OWASP_TOP_10/A7"] [tag "PCI/6.5.10"] [hostname "<DOMAIN>"] [uri "/sites/default/files/pdf_imagenes/Cabecera_PDF_SC_SUMADOS.png"] [unique_id "ZAioeYUtHj9div7cW2O1CwAAAFQ"]

#3 ✨ DomPDF remote images blocked/broken due to missing user agent Needs work works for me :-)

left a comment on the MR

#3 MR worked great for me.
Did need to put in a user-agent in the new fields https://www.whatismybrowser.com/guides/the-latest-user-agent/chrome

Thanks for reviewing.

I don't think [error] Session has not been set is related to the update hook though as the documentation for hook_post_update_NAME states that a return value can be string|null:

string|null Optionally, hook_post_update_NAME() hooks may return a translated string that will be displayed to the user after the update has completed. If no message is returned, no message will be presented to the user.

This issue appears to cover the same/similar session error: https://www.drupal.org/project/entity_print/issues/3383187 🐛 Unexpected error with print engine PhpWkhtmlToPdf or DomPdf: Session has not been set Needs review