components/translate/content/common/translate.mojom

// Copyright 2016 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

module translate.mojom;

import "mojo/public/mojom/base/file.mojom";
import "mojo/public/mojom/base/time.mojom";
import "mojo/public/mojom/base/string16.mojom";
import "url/mojom/url.mojom";

enum TranslateError {
  NONE,
  NETWORK,
  INITIALIZATION_ERROR,
  UNKNOWN_LANGUAGE,
  UNSUPPORTED_LANGUAGE,
  IDENTICAL_LANGUAGES,
  TRANSLATION_ERROR,
  TRANSLATION_TIMEOUT,
  UNEXPECTED_SCRIPT_ERROR,
  BAD_ORIGIN,
  SCRIPT_LOAD_ERROR,
  TRANSLATE_ERROR_MAX,
};

// This struct is populated a TranslateAgent to inform the browser about the
// result of the language detection model. Corresponds to
// LanguageDetectionDetails defined in language_detection_details.h.
struct LanguageDetectionDetails {
  // All the elements in this section are used for to make decisions related
  // to page translation.
  //
  // The URL corresponding to the main frame that had its language detected.
  // Used by the TranslateDriver to determine if the page is eligible for
  // translation.
  url.mojom.Url url;
  // The calculated language based on the language detection model's prediction
  // and reliability, content language, and the page language attribute. Used to
  // determine if the page should be considered for translation.
  string adopted_language;
  // Whether no translate was specified within HTML tag to prevent
  // initiating a translation for the corresponding page load. If true,
  // the page content should not be translated.
  bool has_notranslate;

  // All the elements below are used only for debugging and metrics purposes,
  // e.g., translate-internals.
  //
  // The time at which language the language detection was performed. Used only
  // for debugging.
  mojo_base.mojom.Time time;
  // The intended language of the audience of the content as specified by the
  // HTTP header. Used only for debugging.
  string content_language;
  // The language predicted by the model based on the text of the page. Used
  // only for debugging.
  string model_detected_language;
  // Whether the language prediction from the model is considered reliable
  // for use, i.e., if the model's score is above a set threshold. Used
  // only for debugging.
  bool is_model_reliable;
  // The language of the document specified by the HTML lang attribute.
  // Used only for debugging.
  string html_root_language;
  // The content of the page that language detection has be executed on.
  // Used only for debugging.
  mojo_base.mojom.String16 contents;
  // The relability score of the language prediction made by the detection
  // model, the units of the score depends on the model but generally higher is
  // better. Used only for debugging and metrics.
  float model_reliability_score;
  // The version of the language detection model used to predict
  // the language of the page. Used only for debugging.
  string detection_model_version;
};

// Handles language translation. This is used by the browser process to
// direct a renderer to detect the language details of a frame and translate
// the language of a frame (or revert a previous translation of the contents
// of a frame.
interface TranslateAgent {
  // Requests that the frame's language details be detected and returned to
  // the browser process. This includes the html root language, the content
  // language metadata, and whether the notranslate metadata is present.
  GetWebLanguageDetectionDetails()
        => (string content_meta_language, string html_root_lang,
          url.mojom.Url url, bool has_notranslate_meta);

  // Requests that the frame be translated from |source_lang| to
  // |target_lang|.
  //
  // If a Translate request is already in progress with a matching
  // |target_lang|, this request will respond with |cancelled| set
  // to |true|.
  //
  // If a Translate request is already in progress with a different
  // |target_lang|, that request will respond with |cancelled| set
  // to |true| and this request will proceed normally.
  //
  // If |cancelled| is |true| all other response values should be
  // ignored.
  TranslateFrame(string translate_script, string source_lang,
                 string target_lang)
      => (bool cancelled, string original_lang, string translated_lang,
          TranslateError error);

  // Requests that the frame be reverted to its original language with
  // no translation applied.
  RevertTranslation();
};

// Reports when page is ready for translation. This is used by the
// renderer of a main frame to report its detected language to the
// browser process and provides the translation interface back to itself.
interface ContentTranslateDriver {
  // Notification that a new page is ready to translate,
  // and the language for it has been determined.
  RegisterPage(pending_remote<TranslateAgent> translate_agent,
               LanguageDetectionDetails details, bool translation_critiera_met);

  // Request that the language detection model being loaded and returned
  // for use by the TranslateAgent.
  GetLanguageDetectionModel()
        => (mojo_base.mojom.File? model_file);

};