From be40b07307ed36061b38b54dc6e45ce4d5081f98 Mon Sep 17 00:00:00 2001
From: Anas Abou Allaban <aabouallaban@pm.me>
Date: Wed, 1 Apr 2020 09:57:45 -0400
Subject: [PATCH 1/7] Add type declaration file for v0.7.0

Signed-off-by: Anas Abou Allaban <aabouallaban@pm.me>
---
 native_client/javascript/README.md     |  12 ++
 native_client/javascript/index.d.ts    | 198 +++++++++++++++++++++++++
 native_client/javascript/tsconfig.json |  18 +++
 3 files changed, 228 insertions(+)
 create mode 100644 native_client/javascript/index.d.ts
 create mode 100644 native_client/javascript/tsconfig.json

diff --git a/native_client/javascript/README.md b/native_client/javascript/README.md
index 89ebc594..2247cb02 100644
--- a/native_client/javascript/README.md
+++ b/native_client/javascript/README.md
@@ -1 +1,13 @@
 Full project description and documentation on GitHub: [https://github.com/mozilla/DeepSpeech](https://github.com/mozilla/DeepSpeech).
+
+## Generating TypeScript Type Definitions
+
+You can generate the TypeScript type declaration file using `dts-gen`.
+This requires a compiled/installed version of the DeepSpeech NodeJS client.
+
+To generate a new `index.d.ts` type declaration file, run:
+
+```sh
+npm install -g dts-gen
+dts-gen --module deepspeech --file index.d.ts
+```
diff --git a/native_client/javascript/index.d.ts b/native_client/javascript/index.d.ts
new file mode 100644
index 00000000..c944876d
--- /dev/null
+++ b/native_client/javascript/index.d.ts
@@ -0,0 +1,198 @@
+declare module 'deepspeech' {
+/**
+ * Stores text of an individual token, along with its timing information
+ */
+export interface TokenMetadata {
+    text: string;
+    timestep: number;
+    start_time: number;
+}
+
+/**
+ * A single transcript computed by the model, including a confidence value and
+ * the metadata for its constituent tokens.
+ */
+export interface CandidateTranscript {
+    tokens: TokenMetadata[];
+    confidence: number;
+}
+
+/**
+ * An array of CandidateTranscript objects computed by the model.
+ */
+export interface Metadata {
+    transcripts: CandidateTranscript[];
+}
+
+/**
+ * @class
+ * Provides an interface to a DeepSpeech stream. The constructor cannot be called
+ * directly, use :js:func:`Model.createStream`.
+ */
+export class Stream {}
+
+/**
+ * An object providing an interface to a trained DeepSpeech model.
+ *
+ * @param aModelPath The path to the frozen model graph.
+ *
+ * @throws on error
+ */
+export class Model {
+constructor(aModelPath: string)
+
+/**
+ * Get beam width value used by the model. If :js:func:Model.setBeamWidth was
+ * not called before, will return the default value loaded from the model file.
+ * 
+ * @return Beam width value used by the model.
+ */
+beamWidth(): number;
+
+/**
+ * Set beam width value used by the model.
+ * 
+ * @param The beam width used by the model. A larger beam width value generates better results at the cost of decoding time.
+ *
+ * @return Zero on success, non-zero on failure.
+ */
+setBeamWidth(aBeamWidth: number): number;
+
+/**
+ * Return the sample rate expected by the model.
+ *
+ * @return Sample rate.
+ */
+sampleRate(): number;
+
+/**
+ * Enable decoding using an external scorer.
+ *
+ * @param aScorerPath The path to the external scorer file.
+ *
+ * @return Zero on success, non-zero on failure (invalid arguments).
+ */
+enableExternalScorer(aScorerPath: string): number;
+
+/**
+ * Disable decoding using an external scorer.
+ *
+ * @return Zero on success, non-zero on failure (invalid arguments).
+ */
+disableExternalScorer(): number;
+
+/**
+ * Set hyperparameters alpha and beta of the external scorer.
+ *
+ * @param aLMAlpha The alpha hyperparameter of the CTC decoder. Language Model weight.
+ * @param aLMBeta The beta hyperparameter of the CTC decoder. Word insertion weight.
+ *
+ * @return Zero on success, non-zero on failure (invalid arguments).
+ */
+setScorerAlphaBeta(aLMAlpha: number, aLMBeta: number): number;
+
+/**
+ * Use the DeepSpeech model to perform Speech-To-Text.
+ *
+ * @param aBuffer A 16-bit, mono raw audio signal at the appropriate sample rate (matching what the model was trained on).
+ *
+ * @return The STT result. Returns undefined on error.
+ */
+stt(aBuffer: object): string;
+
+/**
+ * Use the DeepSpeech model to perform Speech-To-Text and output metadata
+ * about the results.
+ *
+ * @param aBuffer A 16-bit, mono raw audio signal at the appropriate sample rate (matching what the model was trained on).
+ * @param aNumResults Maximum number of candidate transcripts to return. Returned list might be smaller than this.
+ * Default value is 1 if not specified.
+ *
+ * @return :js:func:`Metadata` object containing multiple candidate transcripts. Each transcript has per-token metadata including timing information.
+ * The user is responsible for freeing Metadata by calling :js:func:`FreeMetadata`. Returns undefined on error.
+ */
+sttWithMetadata(aBuffer: object, aNumResults: number): Metadata;
+
+/**
+ * Create a new streaming inference state. One can then call :js:func:`Stream.feedAudioContent` and :js:func:`Stream.finishStream` on the returned stream object.
+ *
+ * @return a :js:func:`Stream` object that represents the streaming state.
+ *
+ * @throws on error
+ */
+createStream(): object;
+
+/**
+ * Feed audio samples to an ongoing streaming inference.
+ *
+ * @param aBuffer An array of 16-bit, mono raw audio samples at the
+ *                 appropriate sample rate (matching what the model was trained on).
+ */
+feedAudioContent(aBuffer: object): void;
+
+/**
+ * Compute the intermediate decoding of an ongoing streaming inference.
+ *
+ * @return The STT intermediate result.
+ */
+intermediateDecode(aSctx: object): string;
+
+/**
+ * Compute the intermediate decoding of an ongoing streaming inference, return results including metadata.
+ *
+ * @param aNumResults Maximum number of candidate transcripts to return. Returned list might be smaller than this. Default value is 1 if not specified.
+ *
+ * @return :js:func:`Metadata` object containing multiple candidate transcripts. Each transcript has per-token metadata including timing information. The user is responsible for freeing Metadata by calling :js:func:`FreeMetadata`. Returns undefined on error.
+ */
+intermediateDecodeWithMetadata (aNumResults: number): Metadata;
+
+/**
+ * Compute the final decoding of an ongoing streaming inference and return the result. Signals the end of an ongoing streaming inference.
+ *
+ * @return The STT result.
+ *
+ * This method will free the stream, it must not be used after this method is called.
+ */
+finishStream(): string;
+
+/**
+ * Compute the final decoding of an ongoing streaming inference and return the results including metadata. Signals the end of an ongoing streaming inference.
+ *
+ * @param aNumResults Maximum number of candidate transcripts to return. Returned list might be smaller than this. Default value is 1 if not specified.
+ *
+ * @return Outputs a :js:func:`Metadata` struct of individual letters along with their timing information. The user is responsible for freeing Metadata by calling :js:func:`FreeMetadata`.
+ *
+ * This method will free the stream, it must not be used after this method is called.
+ */
+finishStreamWithMetadata(aNumResults: number): Metadata;
+}
+
+/**
+ * Frees associated resources and destroys model object.
+ *
+ * @param model A model pointer returned by :js:func:`Model`
+ *
+ */
+export function FreeModel(model: Model): void;
+
+/**
+ * Free memory allocated for metadata information.
+ *
+ * @param metadata Object containing metadata as returned by :js:func:`Model.sttWithMetadata` or :js:func:`Model.finishStreamWithMetadata`
+ */
+export function FreeMetadata(metadata: Metadata): void;
+
+/**
+ * Destroy a streaming state without decoding the computed logits. This
+ * can be used if you no longer need the result of an ongoing streaming
+ * inference and don't want to perform a costly decode operation.
+ *
+ * @param stream A streaming state pointer returned by :js:func:`Model.createStream`.
+ */
+export function FreeStream(stream: object): void;
+
+/**
+ * Print version of this library and of the linked TensorFlow library on standard output.
+ */
+export function Version(): void;
+}
diff --git a/native_client/javascript/tsconfig.json b/native_client/javascript/tsconfig.json
new file mode 100644
index 00000000..a0ce2c4b
--- /dev/null
+++ b/native_client/javascript/tsconfig.json
@@ -0,0 +1,18 @@
+{
+    "compilerOptions": {
+        "baseUrl": ".",
+        "target": "es6",
+        "module": "commonjs",
+        "moduleResolution": "node",
+        "esModuleInterop": true,
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictFunctionTypes": true,
+        "strictNullChecks": true,
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true
+    },
+    "files": [
+        "index.d.ts",
+    ]
+}
\ No newline at end of file

From 510d71353f00ded50076cc242cf0a0858f225b66 Mon Sep 17 00:00:00 2001
From: Anas Abou Allaban <aabouallaban@pm.me>
Date: Wed, 1 Apr 2020 15:17:13 -0400
Subject: [PATCH 2/7] Update README

Signed-off-by: Anas Abou Allaban <aabouallaban@pm.me>
---
 native_client/javascript/README.md     | 16 ++++++++++++++++
 native_client/javascript/tsconfig.json |  2 +-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/native_client/javascript/README.md b/native_client/javascript/README.md
index 2247cb02..9c8cd861 100644
--- a/native_client/javascript/README.md
+++ b/native_client/javascript/README.md
@@ -11,3 +11,19 @@ To generate a new `index.d.ts` type declaration file, run:
 npm install -g dts-gen
 dts-gen --module deepspeech --file index.d.ts
 ```
+
+### Example usage
+
+```javascript
+/// index.ts
+import DeepSpeech from "deepspeech";
+
+let modelPath = '/path/to/model';
+let model = new DeepSpeech.Model(modelPath);
+model.setBeamWidth(1000);
+
+let audioBuffer = ...;
+model.sttWithMetadata(audioBuffer);
+
+FreeModel(model);
+```
diff --git a/native_client/javascript/tsconfig.json b/native_client/javascript/tsconfig.json
index a0ce2c4b..51b30f85 100644
--- a/native_client/javascript/tsconfig.json
+++ b/native_client/javascript/tsconfig.json
@@ -13,6 +13,6 @@
         "forceConsistentCasingInFileNames": true
     },
     "files": [
-        "index.d.ts",
+        "index.d.ts"
     ]
 }
\ No newline at end of file

From 567595aa5a08b91486d0be28d4f0d27d272f7b22 Mon Sep 17 00:00:00 2001
From: Alexandre Lissy <lissyx@lissyx.dyndns.org>
Date: Thu, 2 Apr 2020 14:45:45 +0200
Subject: [PATCH 3/7] Package and expose TypeScript for JS interface

---
 .gitignore                                    |  1 +
 native_client/javascript/Makefile             |  3 +-
 .../javascript/{client.js => client.ts}       | 69 +++++++++----------
 native_client/javascript/index.d.ts           |  2 -
 native_client/javascript/package.json.in      |  5 +-
 native_client/javascript/tsconfig.json        |  5 +-
 6 files changed, 42 insertions(+), 43 deletions(-)
 rename native_client/javascript/{client.js => client.ts} (59%)

diff --git a/.gitignore b/.gitignore
index fe04f7c8..464c21dd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -19,6 +19,7 @@
 /native_client/python/model_wrap.cpp
 /native_client/python/utils_wrap.cpp
 /native_client/javascript/build
+/native_client/javascript/client.js
 /native_client/javascript/deepspeech_wrap.cxx
 /doc/.build/
 /doc/xml-c/
diff --git a/native_client/javascript/Makefile b/native_client/javascript/Makefile
index 5c1db09a..e62c0659 100644
--- a/native_client/javascript/Makefile
+++ b/native_client/javascript/Makefile
@@ -42,7 +42,8 @@ node-wrapper: copy-deps build
 	$(NODE_BUILD_TOOL) $(NODE_PLATFORM_TARGET) $(NODE_RUNTIME) $(NODE_ABI_TARGET) $(NODE_DIST_URL) package $(NODE_BUILD_VERBOSE)
 
 npm-pack: clean package.json index.js
-	npm install node-pre-gyp@0.14.x
+	npm install --prefix=${NPM_ROOT} node-pre-gyp@0.14.x typescript@3.6.2 @types/argparse@1.0.38
+	${NPM_ROOT}/.bin/tsc --outDir dist/ client.ts || true
 	npm pack $(NODE_BUILD_VERBOSE)
 
 deepspeech_wrap.cxx: deepspeech.i
diff --git a/native_client/javascript/client.js b/native_client/javascript/client.ts
similarity index 59%
rename from native_client/javascript/client.js
rename to native_client/javascript/client.ts
index 16dd19e8..e6000fe5 100644
--- a/native_client/javascript/client.js
+++ b/native_client/javascript/client.ts
@@ -1,48 +1,42 @@
 #!/usr/bin/env node
-'use strict';
 
-const Fs = require('fs');
-const Sox = require('sox-stream');
-const Ds = require('./index.js');
-const argparse = require('argparse');
-const MemoryStream = require('memory-stream');
-const Wav = require('node-wav');
-const Duplex = require('stream').Duplex;
-const util = require('util');
+// This is required for process.versions.electron below
+/// <reference types="electron" />
 
-var VersionAction = function VersionAction(options) {
-  options = options || {};
-  options.nargs = 0;
-  argparse.Action.call(this, options);
-}
-util.inherits(VersionAction, argparse.Action);
+import Ds from "./index";
+import * as Fs from "fs";
+import Sox from "sox-stream";
+import * as argparse from "argparse";
 
-VersionAction.prototype.call = function(parser) {
-  console.log('DeepSpeech ' + Ds.Version());
-  let runtime = 'Node';
-  if (process.versions.electron) {
-    runtime = 'Electron';
+const MemoryStream = require("memory-stream");
+const Wav = require("node-wav");
+const Duplex = require("stream").Duplex;
+
+class VersionAction extends argparse.Action {
+  call(parser: argparse.ArgumentParser, namespace: argparse.Namespace, values: string | string[], optionString: string | null) {
+    console.log('DeepSpeech ' + Ds.Version());
+    let runtime = 'Node';
+    if (process.versions.electron) {
+      runtime = 'Electron';
+    }
+    console.error('Runtime: ' + runtime);
+    process.exit(0);
   }
-  console.error('Runtime: ' + runtime);
-  process.exit(0);
 }
 
-var parser = new argparse.ArgumentParser({addHelp: true, description: 'Running DeepSpeech inference.'});
+let parser = new argparse.ArgumentParser({addHelp: true, description: 'Running DeepSpeech inference.'});
 parser.addArgument(['--model'], {required: true, help: 'Path to the model (protocol buffer binary file)'});
 parser.addArgument(['--scorer'], {help: 'Path to the external scorer file'});
 parser.addArgument(['--audio'], {required: true, help: 'Path to the audio file to run (WAV format)'});
-parser.addArgument(['--beam_width'], {help: 'Beam width for the CTC decoder', type: 'int'});
-parser.addArgument(['--lm_alpha'], {help: 'Language model weight (lm_alpha). If not specified, use default from the scorer package.', type: 'float'});
-parser.addArgument(['--lm_beta'], {help: 'Word insertion bonus (lm_beta). If not specified, use default from the scorer package.', type: 'float'});
-parser.addArgument(['--version'], {action: VersionAction, help: 'Print version and exits'});
+parser.addArgument(['--version'], {action: VersionAction, nargs: 0, help: 'Print version and exits'});
 parser.addArgument(['--extended'], {action: 'storeTrue', help: 'Output string from extended metadata'});
-var args = parser.parseArgs();
+let args = parser.parseArgs();
 
-function totalTime(hrtimeValue) {
+function totalTime(hrtimeValue: number[]): string {
   return (hrtimeValue[0] + hrtimeValue[1] / 1000000000).toPrecision(4);
 }
 
-function candidateTranscriptToString(transcript) {
+function candidateTranscriptToString(transcript: Ds.CandidateTranscript): string {
   var retval = ""
   for (var i = 0; i < transcript.tokens.length; ++i) {
     retval += transcript.tokens[i].text;
@@ -52,7 +46,7 @@ function candidateTranscriptToString(transcript) {
 
 console.error('Loading model from file %s', args['model']);
 const model_load_start = process.hrtime();
-var model = new Ds.Model(args['model']);
+let model = new Ds.Model(args['model']);
 const model_load_end = process.hrtime(model_load_start);
 console.error('Loaded model in %ds.', totalTime(model_load_end));
 
@@ -60,7 +54,7 @@ if (args['beam_width']) {
   model.setBeamWidth(args['beam_width']);
 }
 
-var desired_sample_rate = model.sampleRate();
+let desired_sample_rate = model.sampleRate();
 
 if (args['scorer']) {
   console.error('Loading scorer from file %s', args['scorer']);
@@ -78,23 +72,24 @@ const buffer = Fs.readFileSync(args['audio']);
 const result = Wav.decode(buffer);
 
 if (result.sampleRate < desired_sample_rate) {
-  console.error('Warning: original sample rate (' + result.sampleRate + ') ' +
-                'is lower than ' + desired_sample_rate + 'Hz. ' +
-                'Up-sampling might produce erratic speech recognition.');
+  console.error(`Warning: original sample rate ( ${result.sampleRate})` +
+                `is lower than ${desired_sample_rate} Hz. ` +
+                `Up-sampling might produce erratic speech recognition.`);
 }
 
-function bufferToStream(buffer) {
+function bufferToStream(buffer: Buffer) {
   var stream = new Duplex();
   stream.push(buffer);
   stream.push(null);
   return stream;
 }
 
-var audioStream = new MemoryStream();
+let audioStream = new MemoryStream();
 bufferToStream(buffer).
   pipe(Sox({
     global: {
       'no-dither': true,
+      'replay-gain': 'off',
     },
     output: {
       bits: 16,
diff --git a/native_client/javascript/index.d.ts b/native_client/javascript/index.d.ts
index c944876d..50564a02 100644
--- a/native_client/javascript/index.d.ts
+++ b/native_client/javascript/index.d.ts
@@ -1,4 +1,3 @@
-declare module 'deepspeech' {
 /**
  * Stores text of an individual token, along with its timing information
  */
@@ -195,4 +194,3 @@ export function FreeStream(stream: object): void;
  * Print version of this library and of the linked TensorFlow library on standard output.
  */
 export function Version(): void;
-}
diff --git a/native_client/javascript/package.json.in b/native_client/javascript/package.json.in
index bd80f438..8e9215a4 100644
--- a/native_client/javascript/package.json.in
+++ b/native_client/javascript/package.json.in
@@ -2,7 +2,8 @@
     "name" : "$(PROJECT_NAME)",
     "version" : "$(PROJECT_VERSION)",
     "description" : "DeepSpeech NodeJS bindings",
-    "main" : "./index",
+    "main" : "./index.js",
+    "types": "./index.d.ts",
     "bin": {
        "deepspeech": "./client.js"
     },
@@ -13,6 +14,7 @@
        "README.md",
        "client.js",
        "index.js",
+       "index.d.ts",
        "lib/*"
     ],
     "bugs": {
@@ -37,6 +39,7 @@
       "node-wav": "0.0.2"
     },
     "devDependencies": {
+      "electron": "^1.7.9"
     },
     "scripts": {
         "test": "node index.js"
diff --git a/native_client/javascript/tsconfig.json b/native_client/javascript/tsconfig.json
index 51b30f85..f67afbbd 100644
--- a/native_client/javascript/tsconfig.json
+++ b/native_client/javascript/tsconfig.json
@@ -13,6 +13,7 @@
         "forceConsistentCasingInFileNames": true
     },
     "files": [
-        "index.d.ts"
+        "index.d.ts",
+        "client.ts"
     ]
-}
\ No newline at end of file
+}

From bf31b2e351b107fcbaafb0a05cdea7ebe515c190 Mon Sep 17 00:00:00 2001
From: Alexandre Lissy <lissyx@lissyx.dyndns.org>
Date: Mon, 6 Apr 2020 20:50:04 +0200
Subject: [PATCH 4/7] Expose Stream-related within Stream class

---
 native_client/javascript/index.d.ts | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/native_client/javascript/index.d.ts b/native_client/javascript/index.d.ts
index 50564a02..fe9ab459 100644
--- a/native_client/javascript/index.d.ts
+++ b/native_client/javascript/index.d.ts
@@ -23,13 +23,6 @@ export interface Metadata {
     transcripts: CandidateTranscript[];
 }
 
-/**
- * @class
- * Provides an interface to a DeepSpeech stream. The constructor cannot be called
- * directly, use :js:func:`Model.createStream`.
- */
-export class Stream {}
-
 /**
  * An object providing an interface to a trained DeepSpeech model.
  *
@@ -120,7 +113,14 @@ sttWithMetadata(aBuffer: object, aNumResults: number): Metadata;
  * @throws on error
  */
 createStream(): object;
+}
 
+/**
+ * @class
+ * Provides an interface to a DeepSpeech stream. The constructor cannot be called
+ * directly, use :js:func:`Model.createStream`.
+ */
+declare class Stream {
 /**
  * Feed audio samples to an ongoing streaming inference.
  *

From 3581bdf9fec8edb53e38b4e41fc35a049cc857b8 Mon Sep 17 00:00:00 2001
From: Alexandre Lissy <lissyx@lissyx.dyndns.org>
Date: Thu, 2 Apr 2020 15:51:42 +0200
Subject: [PATCH 5/7] Add TypeScript CI

---
 native_client/javascript/Makefile        | 38 +++++++++++++++++-------
 native_client/javascript/package.json.in |  6 +++-
 native_client/javascript/tsconfig.json   |  1 -
 taskcluster/tc-build-utils.sh            | 20 +++----------
 4 files changed, 36 insertions(+), 29 deletions(-)

diff --git a/native_client/javascript/Makefile b/native_client/javascript/Makefile
index e62c0659..0581d648 100644
--- a/native_client/javascript/Makefile
+++ b/native_client/javascript/Makefile
@@ -1,26 +1,37 @@
 NODE_BUILD_TOOL    ?= node-pre-gyp
 NODE_ABI_TARGET    ?= 
 NODE_BUILD_VERBOSE ?= --verbose
+NPM_TOOL           ?= npm
 PROJECT_NAME       ?= deepspeech
 PROJECT_VERSION    ?= $(shell cat ../../VERSION | tr -d '\n')
+NPM_ROOT           ?= $(shell npm root)
+
+NODE_MODULES_BIN   ?= $(NPM_ROOT)/.bin/
+ifeq ($(findstring _NT,$(OS)),_NT)
+# On Windows, we seem to need both in PATH for node-pre-gyp as well as tsc
+# they do not get installed the same way.
+NODE_MODULES_BIN   := $(shell cygpath -u $(NPM_ROOT)/.bin/):$(shell cygpath -u `dirname "$(NPM_ROOT)"`)
+endif
 
 include ../definitions.mk
 
-ifeq ($(TARGET),host-win)
+ifeq ($(findstring _NT,$(OS)),_NT)
 LIBS := '$(shell cygpath -w $(subst .lib,,$(LIBS)))'
 endif
 
+.PHONY: npm-dev
+
 default: build
 
 clean:
-	rm -f deepspeech_wrap.cxx package.json
+	rm -f deepspeech_wrap.cxx package.json package-lock.json
 	rm -rf ./build/
 
 clean-npm-pack:
-	rm -fr ./node_modules/
 	rm -fr ./deepspeech-*.tgz
 
 really-clean: clean clean-npm-pack
+	rm -fr ./node_modules/
 	rm -fr ./lib/
 
 package.json: package.json.in
@@ -29,22 +40,27 @@ package.json: package.json.in
 		-e 's/$$(PROJECT_VERSION)/$(PROJECT_VERSION)/' \
 		package.json.in > package.json && cat package.json
 
-configure: deepspeech_wrap.cxx package.json
-	$(NODE_BUILD_TOOL) configure $(NODE_BUILD_VERBOSE)
+npm-dev: package.json
+ifeq ($(findstring _NT,$(OS)),_NT)
+	# node-gyp@5.x behaves erratically with VS2015 and MSBuild.exe detection
+	$(NPM_TOOL) install node-gyp@4.x
+endif
+	$(NPM_TOOL) install --prefix=$(NPM_ROOT)/../ --ignore-scripts --force --verbose --production=false .
+
+configure: deepspeech_wrap.cxx package.json npm-dev
+	PATH="$(NODE_MODULES_BIN):${PATH}" $(NODE_BUILD_TOOL) configure $(NODE_BUILD_VERBOSE)
 
 build: configure deepspeech_wrap.cxx
-	AS=$(AS) CC=$(CC) CXX=$(CXX) LD=$(LD) CFLAGS="$(CFLAGS)" CXXFLAGS="$(CXXFLAGS)" LDFLAGS="$(RPATH_NODEJS) $(LDFLAGS)" LIBS=$(LIBS) $(NODE_BUILD_TOOL) $(NODE_PLATFORM_TARGET) $(NODE_RUNTIME) $(NODE_ABI_TARGET) $(NODE_DIST_URL) rebuild $(NODE_BUILD_VERBOSE)
+	PATH="$(NODE_MODULES_BIN):${PATH}" AS=$(AS) CC=$(CC) CXX=$(CXX) LD=$(LD) CFLAGS="$(CFLAGS)" CXXFLAGS="$(CXXFLAGS)" LDFLAGS="$(RPATH_NODEJS) $(LDFLAGS)" LIBS=$(LIBS) $(NODE_BUILD_TOOL) $(NODE_PLATFORM_TARGET) $(NODE_RUNTIME) $(NODE_ABI_TARGET) $(NODE_DIST_URL) --no-color rebuild $(NODE_BUILD_VERBOSE)
 
 copy-deps: build
 	$(call copy_missing_libs,lib/binding/*/*/*/deepspeech.node,lib/binding/*/*/)
 
 node-wrapper: copy-deps build
-	$(NODE_BUILD_TOOL) $(NODE_PLATFORM_TARGET) $(NODE_RUNTIME) $(NODE_ABI_TARGET) $(NODE_DIST_URL) package $(NODE_BUILD_VERBOSE)
+	PATH="$(NODE_MODULES_BIN):${PATH}" $(NODE_BUILD_TOOL) $(NODE_PLATFORM_TARGET) $(NODE_RUNTIME) $(NODE_ABI_TARGET) $(NODE_DIST_URL) --no-color package $(NODE_BUILD_VERBOSE)
 
-npm-pack: clean package.json index.js
-	npm install --prefix=${NPM_ROOT} node-pre-gyp@0.14.x typescript@3.6.2 @types/argparse@1.0.38
-	${NPM_ROOT}/.bin/tsc --outDir dist/ client.ts || true
-	npm pack $(NODE_BUILD_VERBOSE)
+npm-pack: clean package.json index.js npm-dev
+	PATH="$(NODE_MODULES_BIN):${PATH}" tsc && $(NPM_TOOL) pack $(NODE_BUILD_VERBOSE)
 
 deepspeech_wrap.cxx: deepspeech.i
 	swig -version
diff --git a/native_client/javascript/package.json.in b/native_client/javascript/package.json.in
index 8e9215a4..22c3363c 100644
--- a/native_client/javascript/package.json.in
+++ b/native_client/javascript/package.json.in
@@ -39,7 +39,11 @@
       "node-wav": "0.0.2"
     },
     "devDependencies": {
-      "electron": "^1.7.9"
+      "electron": "^1.7.9",
+      "node-gyp": "4.x - 5.x",
+      "typescript": "3.6.x",
+      "@types/argparse": "1.0.x",
+      "@types/node": "13.9.x"
     },
     "scripts": {
         "test": "node index.js"
diff --git a/native_client/javascript/tsconfig.json b/native_client/javascript/tsconfig.json
index f67afbbd..d67d7bce 100644
--- a/native_client/javascript/tsconfig.json
+++ b/native_client/javascript/tsconfig.json
@@ -9,7 +9,6 @@
         "noImplicitThis": true,
         "strictFunctionTypes": true,
         "strictNullChecks": true,
-        "noEmit": true,
         "forceConsistentCasingInFileNames": true
     },
     "files": [
diff --git a/taskcluster/tc-build-utils.sh b/taskcluster/tc-build-utils.sh
index 0a9b633b..26234a4f 100755
--- a/taskcluster/tc-build-utils.sh
+++ b/taskcluster/tc-build-utils.sh
@@ -105,16 +105,10 @@ do_deepspeech_nodejs_build()
   # Python 2.7 is required for node-pre-gyp, it is only required to force it on
   # Windows
   if [ "${OS}" = "${TC_MSYS_VERSION}" ]; then
-    NPM_ROOT=$(cygpath -u "$(npm root)")
-    PYTHON27=":/c/Python27"
-    # node-gyp@5.x behaves erratically with VS2015 and MSBuild.exe detection
-    npm install node-gyp@4.x node-pre-gyp
-  else
-    NPM_ROOT="$(npm root)"
-    npm install node-gyp@5.x node-pre-gyp
+    PYTHON27="/c/Python27"
   fi
 
-  export PATH="$NPM_ROOT/.bin/${PYTHON27}:$PATH"
+  export PATH="${PYTHON27}:$PATH"
 
   for node in ${SUPPORTED_NODEJS_VERSIONS}; do
     EXTRA_CFLAGS="${EXTRA_LOCAL_CFLAGS}" EXTRA_LDFLAGS="${EXTRA_LOCAL_LDFLAGS}" EXTRA_LIBS="${EXTRA_LOCAL_LIBS}" make -C native_client/javascript \
@@ -157,16 +151,10 @@ do_deepspeech_npm_package()
   # Python 2.7 is required for node-pre-gyp, it is only required to force it on
   # Windows
   if [ "${OS}" = "${TC_MSYS_VERSION}" ]; then
-    NPM_ROOT=$(cygpath -u "$(npm root)")
-    PYTHON27=":/c/Python27"
-    # node-gyp@5.x behaves erratically with VS2015 and MSBuild.exe detection
-    npm install node-gyp@4.x node-pre-gyp
-  else
-    NPM_ROOT="$(npm root)"
-    npm install node-gyp@5.x node-pre-gyp
+    PYTHON27="/c/Python27"
   fi
 
-  export PATH="$NPM_ROOT/.bin/$PYTHON27:$PATH"
+  export PATH="${NPM_BIN}${PYTHON27}:$PATH"
 
   all_tasks="$(curl -s https://community-tc.services.mozilla.com/api/queue/v1/task/${TASK_ID} | python -c 'import json; import sys; print(" ".join(json.loads(sys.stdin.read())["dependencies"]));')"
 

From 5723dba1804b512f892c5117fe57526d71edead0 Mon Sep 17 00:00:00 2001
From: Alexandre Lissy <lissyx@lissyx.dyndns.org>
Date: Mon, 6 Apr 2020 11:35:13 +0200
Subject: [PATCH 6/7] Update doc for TypeScript support

---
 doc/NodeJS-API.rst                 |  2 ++
 doc/NodeJS-Examples.rst            | 10 +++++-----
 doc/USING.rst                      |  4 +++-
 native_client/javascript/README.md | 17 +++--------------
 4 files changed, 13 insertions(+), 20 deletions(-)

diff --git a/doc/NodeJS-API.rst b/doc/NodeJS-API.rst
index b6170b5b..7593150c 100644
--- a/doc/NodeJS-API.rst
+++ b/doc/NodeJS-API.rst
@@ -1,6 +1,8 @@
 JavaScript (NodeJS / ElectronJS)
 ================================
 
+Support for TypeScript is :download:`provided in index.d.ts<../native_client/javascript/index.d.ts>`
+
 Model
 -----
 
diff --git a/doc/NodeJS-Examples.rst b/doc/NodeJS-Examples.rst
index 7fe4d3b4..83b37870 100644
--- a/doc/NodeJS-Examples.rst
+++ b/doc/NodeJS-Examples.rst
@@ -4,20 +4,20 @@ JavaScript API Usage example
 Creating a model instance and loading model
 -------------------------------------------
 
-.. literalinclude:: ../native_client/javascript/client.js
+.. literalinclude:: ../native_client/javascript/client.ts
    :language: javascript
    :linenos:
-   :lines: 56,69
+   :lines: 49,54
 
 Performing inference
 --------------------
 
-.. literalinclude:: ../native_client/javascript/client.js
+.. literalinclude:: ../native_client/javascript/client.ts
    :language: javascript
    :linenos:
-   :lines: 122
+   :lines: 114,118
 
 Full source code
 ----------------
 
-See :download:`Full source code<../native_client/javascript/client.js>`.
+See :download:`Full source code<../native_client/javascript/client.ts>`.
diff --git a/doc/USING.rst b/doc/USING.rst
index 55631fe8..2e357af1 100644
--- a/doc/USING.rst
+++ b/doc/USING.rst
@@ -125,6 +125,8 @@ Please note that as of now, we support:
  - Node.JS versions 4 to 13.
  - Electron.JS versions 1.6 to 7.1
 
+TypeScript support is also provided.
+
 Alternatively, if you're using Linux and have a supported NVIDIA GPU, you can install the GPU specific package as follows:
 
 .. code-block:: bash
@@ -133,7 +135,7 @@ Alternatively, if you're using Linux and have a supported NVIDIA GPU, you can in
 
 See the `release notes <https://github.com/mozilla/DeepSpeech/releases>`_ to find which GPUs are supported. Please ensure you have the required `CUDA dependency <#cuda-dependency>`_.
 
-See :github:`client.js <native_client/javascript/client.js>` for an example of how to use the bindings.
+See :github:`client.ts <native_client/javascript/client.ts>` for an example of how to use the bindings.
 
 Using the Command-Line client
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/native_client/javascript/README.md b/native_client/javascript/README.md
index 9c8cd861..267fbeba 100644
--- a/native_client/javascript/README.md
+++ b/native_client/javascript/README.md
@@ -5,7 +5,8 @@ Full project description and documentation on GitHub: [https://github.com/mozill
 You can generate the TypeScript type declaration file using `dts-gen`.
 This requires a compiled/installed version of the DeepSpeech NodeJS client.
 
-To generate a new `index.d.ts` type declaration file, run:
+Upon API change, it is required to generate a new `index.d.ts` type declaration
+file, you have to run:
 
 ```sh
 npm install -g dts-gen
@@ -14,16 +15,4 @@ dts-gen --module deepspeech --file index.d.ts
 
 ### Example usage
 
-```javascript
-/// index.ts
-import DeepSpeech from "deepspeech";
-
-let modelPath = '/path/to/model';
-let model = new DeepSpeech.Model(modelPath);
-model.setBeamWidth(1000);
-
-let audioBuffer = ...;
-model.sttWithMetadata(audioBuffer);
-
-FreeModel(model);
-```
+See `client.ts`

From 88ac227ebee8e8fdde93769ca5dab96076be9204 Mon Sep 17 00:00:00 2001
From: Alexandre Lissy <lissyx@lissyx.dyndns.org>
Date: Mon, 6 Apr 2020 11:46:20 +0200
Subject: [PATCH 7/7] Fix decoder doc not generated

---
 doc/index.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/doc/index.rst b/doc/index.rst
index a905d903..eee1977a 100644
--- a/doc/index.rst
+++ b/doc/index.rst
@@ -14,6 +14,8 @@ Welcome to DeepSpeech's documentation!
 
    TRAINING
 
+   Decoder
+
 .. toctree::
    :maxdepth: 2
    :caption: DeepSpeech Model