Speech Rule Engine
==================
[](https://travis-ci.org/zorkow/speech-rule-engine) [](https://david-dm.org/zorkow/speech-rule-engine) [](https://david-dm.org/zorkow/speech-rule-engine#info=devDependencies) [](https://coveralls.io/github/zorkow/speech-rule-engine?branch=master)
NodeJS version of the ChromeVox speech rule engine.
Forked from ChromeVox release 1.31.0
Speech rule engine (SRE) can translate XML expressions into speech strings according to rules that
can be specified in a syntax using Xpath expressions. It was originally designed for translation
of MathML and MathJax DOM elements for the ChromeVox screen reader.
Besides the rules originally designed for the use in ChromeVox, it also has an implemententation of the
full set of Mathspeak rules. In addition it contains a library for semantic interpretation and enrichment
of MathML expressions.
There are three ways of using this engine:
1. **Node Module:** Download via npm. This is the easiest way to use the speech
rule engine via its Api and is the preferred option if you just want to include
it in your project.
2. **Standalone Tool:** Download via github and build with make. This is useful
if you want to use the speech rule engine in batch mode or interactivley to add
your own code. Or simply run it with ```npx```, for example to get all SRE options anywhere without local installation run:
```npx speech-rule-engine -h```
3. **Browser Library:** This gives you the option of loading SRE in a browser and
use its full functionality on your webesites.
Node Module
-----------
Install as a node module using npm:
npm install speech-rule-engine
Then import into a running node or a source file using require:
require('speech-rule-engine');
### API #######
Current API functions are divided into three categories.
#### Methods that take a string containing a MathML expression:
| Method | Return Value |
| ---- | ---- |
| `toSpeech(mathml)` | Speech string for the MathML. |
| `toSemantic(mathml)` | XML representation of the semantic tree for the MathML. |
| `toJson(mathml)` | The semantic tree in JSON. This method only works in Node, not in browser mode. |
| `toDescription(mathml)` | The array of auditory description objects of the MathML expression. |
| `toEnriched(mathml)` | The semantically enriched MathML expression. |
**Note that in asynchronous operation mode for these methods to work correctly,
it is necessary to ensure that the Engine is ready for processing. See the
engineReady flag below.**
#### Methods that take an input filename and optionally an output filename:
If the output filename is not provided, output will be written to stdout.
| Method | Return Value |
| ---- | ---- |
| `file.toSpeech(input, output)` | Speech string for the MathML. |
| `file.toSemantic(input, output)` | XML representation of the semantic tree for the MathML. |
| `file.toJson(input, output)` | The semantic tree in JSON. This method only works in Node, not in browser mode. |
| `file.toDescription(input, output)` | The array of auditory description objects of the MathML expression. |
| `file.toEnriched(input, output)` | The semantically enriched MathML expression. |
#### A method for setting up and controlling the behaviour of the Speech Rule Engine:
It takes a feature vector (an object of option/value pairs) to parameterise the
Speech Rule Engine.
setupEngine(options);
Most common options are
| Option | Value |
| ---- | ---- |
| *domain* | Domain or subject area of speech rules (e.g., mathspeak, emacspeak).|
| *style* | Style of speech rules (e.g., brief).|
| *locale* | Language locale in 639-1. Currently available: en, es |
| *markup*| Set the markup: ```none```, ```ssml```, ```sable```, ```voicexml```, ```acss``` |
| *walker* | A walker to use for interactive exploration: ```None```, ```Syntax```, ```Semantic```, ```Table``` |
Observe that some speech rule domains only make sense with semantics switched on
or off and that not every domain implements every style. See also the
description of the command line parameters in the next section for more details.
Options for enriched MathML output:
| Option | Value |
| ---- | ---- |
| *speech* | Depth to which generated speech is stored in attributes during semantic enrichment. Values are ```none```, ```shallow```, ```deep```. Default is ```none```. |
| *structure* | If set, includes a `structure` attribute in the enriched MathML that summarises the structure of the semantic tree in form of an sexpression. |
Other options to give more fine grained control of the SRE that are useful during development are:
| Option | Value |
| ---- | ---- |
| *cache* | Boolean flag to switch expression caching during speech generation. Default is ```true```. |
| *strict* | Boolean flag indicating if only a directly matching rule should be used. I.e., no default rules are used in case a rule is not available for a particular domain, style, etc. Default is ```false```. |
| *mode* | The running mode for SRE: ```sync```, ```async```, ```http``` |
| *json* | URL where to pull the json speech rule files from. |
| *xpath* | URL where to pull an xpath library from. This is important for environments not supporting xpath, e.g., IE or Edge. |
Deprecated Options
| Option | Value |
| ---- | ---- |
| *semantics* | Boolean flag to switch **OFF** semantic interpretation. **Non-semantic rule sets are deprecated.** |
| *rules* | A list of rulesets to use by SRE. This allows to artificially restrict available speech rules, which can be useful for testing and during rule development. ***Always expects a list, even if only one rule set is supplied!*** |
|| **Note that setting rule sets is no longer useful with the new rule indexing structures.** |
#### Experimental methods for navigating math expressions:
For the following methods sre maintains an internal state, hence they are only
really useful when running in browser or in a Node REPL. Hence they are not
exposed via the command line interface.
| Method | Return Value |
| ---- | ---- |
| `walk(input)` | Speech string for the MathML. |
| `move(keycode)` | Speech string after the move. Keycodes are numerical strings representing cursor keys, space, enter, etc. |
#### Other API functions and flags #########
| Method | Return Value |
| ---- | ---- |
| `pprintXML(string)` | Returns pretty printed version of a serialised XML string. |
| `version` | Returns SRE's version number. |
| `engineReady()` | Returns flag indicating that the engine is ready for procssing (i.e., all necessary rule files have been loaded, the engine is done updating, etc.). **This is important in asynchronous settings.** |
Standalone Tool
---------------
Install dependencies either by running:
npm install
Or install them manually. SRE depends on the following libraries:
google-closure-compiler
google-closure-library
xmldom-sre
wicked-good-xpath
commander
xml-mapping
### Build #############
Depending on your setup you might need to adapt the NODEJS and NODE_MODULES
variable in the Makefile. Then simply run
make
This will make both the command line executable and the interactive load script.
### Run on command line ############
SRE can be run on the command line by providing a set of processing options and
either a list of input files or a inputting an XML expression manually.
bin/sre [options] infile1 infile2 infile3 ...
For example running
bin/sre -j -p resources/samples/sample1.xml resources/samples/sample2.xml
will return the semantic tree in JSON as well as the speech translation for the
expressions in the two sample files.
(Note, that `-p` is the default option if no processing options are given).
SRE also enables direct input from command line. For example, running
bin/sre -j -p
will wait for a complete XML expression to be input for translation. Similarly,
shell piping is allowed:
bin/sre -j -p < resources/samples/sample1.xml
Note, that when providing the `-o outfile` option output is saved into the given file.
However, when processing from file only the very last output is saved, while when
processing via pipes or command line input all output is saved.
### Run on command line (old) ############
__Note that the `-i` option is deprecated and will be removed in future releases.__
bin/sre -i infile -o outfile
As an example run
bin/sre -i resources/samples/sample1.xml -o sample1.txt
### Run interactively ############
Import into a running node process
require('./lib/sre4node.js');
Note, that this will import the full functionality of the speech rule engine in
the sre namespace and of the closure library in the goog namespace.
### Command Line Options ###########
The following is a list of command line options for the speech rule engine.
| Short | Long | Meaning |
| ----- | ---- | :------- |
| -i | --input [name] | Input file [name]. **This option is deprecated!** |
| -o | --output [name] | Output file [name].
||| If not given output is printed to stdout. |
| | |
| | |
| | |
| -d | --domain [name] | Domain or subject area [name]. |
||| This refers to a particular subject type of speech rules or subject area rules are defined for (e.g., mathspeak, physics). |
||| If no domain parameter is provided, domain default is used. |
| -t | --style [name] | Speech style [name]. |
||| Selects a particular speech style (e.g., brief). |
||| If no style parameter is provided, style default is used. |
| -c | --locale | Language locale in ISO 639-1. |
| -s | --semantics | Switch on semantics interpretation. |
||| **This option is deprecated.** |
||| Note, that some speech rule domains only make sense with semantics switched on or off. |
| -k | --markup [name] | Generate speech output with markup tags. Currently supported SSML, VoiceXML, Sable, ACSS (as sexpressions for Emacsspeak) |
| | |
| | |
| | |
| -p | --speech | Generate speech output (default). |
| -a | --audit | Generate auditory descriptions (JSON format). |
| -j | --json | Generate JSON of semantic tree. |
| -x | --xml | Generate XML of semantic tree. |
| | |
| | |
| | |
| -m | --mathml | Generate enriched MathML. |
| -g | --generate [depth] | Include generated speech in enriched MathML. Supported values: none, shallow, deep (default: none) |
| -r | --structure | Include structure attribute in enriched MathML. |
| | |
| | |
| | |
| -v | --verbose | Verbose mode. Print additional information, useful for debugging. |
| -l | --log [name] | Log file [name]. Verbose output is redirected to this file. |
||| If not given verbose output is printed to stdout. |
| -h | --help | Usage information and enumerates all available domains and styles. |
||| Note that not every style is implemented in every domain. |
| -V | --version | Outputs the version number |
Browser Library
---------------
SRE can be used as a browser ready library giving you the option of loading it
in a browser and use its full functionality on your webesites.
### Usage #############
Build SRE with
make browser
Then include the resulting file ``sre_browser.js`` in your website in a script tag
``` html
```
The full functionality is now available in the ``sre`` namespace. The most
important API functions are also available in ``SRE``.
### Configuration ####
In addition to programmatically configuring SRE using the ``setupEngine``
method, you can also include a configuration element in a website, that can take the same options as ``setupEngine``.
For example the configuration element
``` html
```
will cause SRE to load JSON files from rawgit and for IE or Edge it will also load Google's
[wicked good xpath library](https://github.com/google/wicked-good-xpath). In addition the speech rules are set to ``mathspeak`` in ``super brief`` style.
**Make sure the configuration element comes before the script tag loading SRE in your website!**
MathJax Library
---------------
make mathjax
generates a build specific for [MathJax](https://mathjax.org) in ``mathjax_sre.js``.
SRE can then be configured locally on webpages as described above.
Developers Notes
----------------
### Build Options
Other make targets useful during development are:
make test
Runs all the tests using Node's assert module. Output is pretty printed to stdout.
make lint
Runs the closure linter tool. To use this option, you need to install the node package
npm install closure-linter-wrapper
To automatically fix some of linting errors run:
make fixjsstyle
Note, that all JavaScript code in this repository is fully linted and compiles error free with respect to the strictest possible closure compiler settings, however, not using the ``newCheckTypes`` option.
When creating a pull request, please make sure that your code compiles and is fully linted.
### Node Package
The speech rule engine is published as a node package in fully compiled form, together with the JSON libraries for translating atomic expressions. All relevant files are in the lib subdirectory.
To publish the node package run
npm publish
This first builds the package by executing
make publish
This make command is also useful for local testing of the package.
### Documentation
To generate documentation from the [JSDOC](http://usejsdoc.org/), simply run
make docs
This will generate documentation for the source coude and test code in the directories ``docs/src`` and ``docs/tests``, respectively.