microsoft/vscode-languagedetection
Publicmirrored fromhttps://github.com/microsoft/vscode-languagedetectionAvailable
lib/index.ts
214lines · modecode
| 1 | import { Rank, tensor, Tensor, io, setBackend, env } from '@tensorflow/tfjs-core'; |
| 2 | import { GraphModel, loadGraphModel } from '@tensorflow/tfjs-converter'; |
| 3 | import '@tensorflow/tfjs-backend-cpu'; |
| 4 | |
| 5 | export interface ModelResult { |
| 6 | languageId: string; |
| 7 | confidence: number; |
| 8 | } |
| 9 | |
| 10 | class InMemoryIOHandler implements io.IOHandler { |
| 11 | |
| 12 | constructor(private readonly modelJSON: io.ModelJSON, |
| 13 | private readonly weights: ArrayBuffer) { |
| 14 | } |
| 15 | |
| 16 | async load(): Promise<io.ModelArtifacts> { |
| 17 | // We do not allow both modelTopology and weightsManifest to be missing. |
| 18 | const modelTopology = this.modelJSON.modelTopology; |
| 19 | const weightsManifest = this.modelJSON.weightsManifest; |
| 20 | if (modelTopology === null && weightsManifest === null) { |
| 21 | throw new Error( |
| 22 | `The model contains neither model topology or manifest for weights.`); |
| 23 | } |
| 24 | |
| 25 | return this.getModelArtifactsForJSON( |
| 26 | this.modelJSON, (weightsManifest) => this.loadWeights(weightsManifest)); |
| 27 | } |
| 28 | |
| 29 | private async getModelArtifactsForJSON( |
| 30 | modelJSON: io.ModelJSON, |
| 31 | loadWeights: (weightsManifest: io.WeightsManifestConfig) => Promise<[ |
| 32 | /* weightSpecs */ io.WeightsManifestEntry[], /* weightData */ ArrayBuffer |
| 33 | ]>): Promise<io.ModelArtifacts> { |
| 34 | const modelArtifacts: io.ModelArtifacts = { |
| 35 | modelTopology: modelJSON.modelTopology, |
| 36 | format: modelJSON.format, |
| 37 | generatedBy: modelJSON.generatedBy, |
| 38 | convertedBy: modelJSON.convertedBy |
| 39 | }; |
| 40 | |
| 41 | if (modelJSON.trainingConfig !== null) { |
| 42 | modelArtifacts.trainingConfig = modelJSON.trainingConfig; |
| 43 | } |
| 44 | if (modelJSON.weightsManifest !== null) { |
| 45 | const [weightSpecs, weightData] = |
| 46 | await loadWeights(modelJSON.weightsManifest); |
| 47 | modelArtifacts.weightSpecs = weightSpecs; |
| 48 | modelArtifacts.weightData = weightData; |
| 49 | } |
| 50 | if (modelJSON.signature !== null) { |
| 51 | modelArtifacts.signature = modelJSON.signature; |
| 52 | } |
| 53 | if (modelJSON.userDefinedMetadata !== null) { |
| 54 | modelArtifacts.userDefinedMetadata = modelJSON.userDefinedMetadata; |
| 55 | } |
| 56 | if (modelJSON.modelInitializer !== null) { |
| 57 | modelArtifacts.modelInitializer = modelJSON.modelInitializer; |
| 58 | } |
| 59 | |
| 60 | return modelArtifacts; |
| 61 | } |
| 62 | |
| 63 | private async loadWeights(weightsManifest: io.WeightsManifestConfig): Promise<[io.WeightsManifestEntry[], ArrayBuffer]> { |
| 64 | const weightSpecs = []; |
| 65 | for (const entry of weightsManifest) { |
| 66 | weightSpecs.push(...entry.weights); |
| 67 | } |
| 68 | |
| 69 | return [weightSpecs, this.weights]; |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | export interface ModelOperationsOptions { |
| 74 | modelJsonLoaderFunc?: () => Promise<{ [key:string]: any }>; |
| 75 | weightsLoaderFunc?: () => Promise<ArrayBuffer>; |
| 76 | minContentSize?: number; |
| 77 | maxContentSize?: number; |
| 78 | normalizeNewline?: boolean; |
| 79 | } |
| 80 | |
| 81 | export class ModelOperations { |
| 82 | private static DEFAULT_MAX_CONTENT_SIZE = 100000; |
| 83 | private static DEFAULT_MIN_CONTENT_SIZE = 20; |
| 84 | |
| 85 | private static NODE_MODEL_JSON_FUNC: () => Promise<{ [key:string]: any }> = async () => { |
| 86 | const fs = await import('fs'); |
| 87 | const path = await import('path'); |
| 88 | |
| 89 | return new Promise<any>((resolve, reject) => { |
| 90 | fs.readFile(path.join(__dirname, '..', '..', 'model', 'model.json'), (err, data) => { |
| 91 | if(err) { |
| 92 | reject(err); |
| 93 | return; |
| 94 | } |
| 95 | resolve(JSON.parse(data.toString())); |
| 96 | }); |
| 97 | }); |
| 98 | } |
| 99 | |
| 100 | private static NODE_WEIGHTS_FUNC: () => Promise<ArrayBuffer> = async () => { |
| 101 | const fs = await import('fs'); |
| 102 | const path = await import('path'); |
| 103 | |
| 104 | return new Promise<ArrayBuffer>((resolve, reject) => { |
| 105 | fs.readFile(path.join(__dirname, '..', '..', 'model', 'group1-shard1of1.bin'), (err, data) => { |
| 106 | if(err) { |
| 107 | reject(err); |
| 108 | return; |
| 109 | } |
| 110 | resolve(data.buffer); |
| 111 | }); |
| 112 | }); |
| 113 | } |
| 114 | |
| 115 | private _model: GraphModel | undefined; |
| 116 | private _modelJson: io.ModelJSON | undefined; |
| 117 | private _weights: ArrayBuffer | undefined; |
| 118 | private readonly _minContentSize: number; |
| 119 | private readonly _maxContentSize: number; |
| 120 | private readonly _modelJsonLoaderFunc: () => Promise<{ [key:string]: any }>; |
| 121 | private readonly _weightsLoaderFunc: () => Promise<ArrayBuffer>; |
| 122 | private readonly _normalizeNewline: boolean; |
| 123 | |
| 124 | constructor(modelOptions?: ModelOperationsOptions) { |
| 125 | this._modelJsonLoaderFunc = modelOptions?.modelJsonLoaderFunc ?? ModelOperations.NODE_MODEL_JSON_FUNC; |
| 126 | this._weightsLoaderFunc = modelOptions?.weightsLoaderFunc ?? ModelOperations.NODE_WEIGHTS_FUNC; |
| 127 | this._minContentSize = modelOptions?.minContentSize ?? ModelOperations.DEFAULT_MIN_CONTENT_SIZE; |
| 128 | this._maxContentSize = modelOptions?.maxContentSize ?? ModelOperations.DEFAULT_MAX_CONTENT_SIZE; |
| 129 | this._normalizeNewline = modelOptions?.normalizeNewline ?? true; |
| 130 | } |
| 131 | |
| 132 | private async getModelJSON(): Promise<io.ModelJSON> { |
| 133 | if (this._modelJson) { |
| 134 | return this._modelJson; |
| 135 | } |
| 136 | |
| 137 | // TODO: validate model.json |
| 138 | this._modelJson = await this._modelJsonLoaderFunc() as io.ModelJSON; |
| 139 | return this._modelJson; |
| 140 | } |
| 141 | |
| 142 | private async getWeights() { |
| 143 | if (this._weights) { |
| 144 | return this._weights; |
| 145 | } |
| 146 | |
| 147 | // TODO: validate weights |
| 148 | this._weights = await this._weightsLoaderFunc(); |
| 149 | return this._weights; |
| 150 | } |
| 151 | |
| 152 | private async loadModel() { |
| 153 | if (this._model) { |
| 154 | return; |
| 155 | } |
| 156 | |
| 157 | env().set('IS_NODE', false); |
| 158 | if(!(await setBackend('cpu'))) { |
| 159 | throw new Error('Unable to set backend to CPU.'); |
| 160 | } |
| 161 | |
| 162 | const resolvedModelJSON = await this.getModelJSON(); |
| 163 | const resolvedWeights = await this.getWeights(); |
| 164 | this._model = await loadGraphModel(new InMemoryIOHandler(resolvedModelJSON, resolvedWeights)); |
| 165 | } |
| 166 | |
| 167 | public async runModel(content: string): Promise<Array<ModelResult>> { |
| 168 | if (!content || content.length < this._minContentSize) { |
| 169 | return []; |
| 170 | } |
| 171 | |
| 172 | await this.loadModel(); |
| 173 | |
| 174 | // larger files cause a "RangeError: Maximum call stack size exceeded" in tfjs. |
| 175 | // So grab the first X characters as that should be good enough for guessing. |
| 176 | if (content.length >= this._maxContentSize) { |
| 177 | content = content.substring(0, this._maxContentSize); |
| 178 | } |
| 179 | |
| 180 | if (this._normalizeNewline) { |
| 181 | content = content.replace(/\r\n/g, '\n'); |
| 182 | } |
| 183 | |
| 184 | // call out to the model |
| 185 | const predicted = await this._model!.executeAsync(tensor([content])); |
| 186 | const probabilitiesTensor: Tensor<Rank> = Array.isArray(predicted) ? predicted[0]! : predicted; |
| 187 | const languageTensor: Tensor<Rank> = Array.isArray(predicted) ? predicted[1]! : predicted; |
| 188 | const probabilities = probabilitiesTensor.dataSync() as Float32Array; |
| 189 | const langs: Array<string> = languageTensor.dataSync() as any; |
| 190 | |
| 191 | const objs: Array<ModelResult> = []; |
| 192 | for (let i = 0; i < langs.length; i++) { |
| 193 | objs.push({ |
| 194 | languageId: langs[i], |
| 195 | confidence: probabilities[i], |
| 196 | }); |
| 197 | } |
| 198 | |
| 199 | let maxIndex = 0; |
| 200 | for (let i = 0; i < probabilities.length; i++) { |
| 201 | if (probabilities[i] > probabilities[maxIndex]) { |
| 202 | maxIndex = i; |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | return objs.sort((a, b) => { |
| 207 | return b.confidence - a.confidence; |
| 208 | }); |
| 209 | } |
| 210 | |
| 211 | public dispose() { |
| 212 | this._model?.dispose(); |
| 213 | } |
| 214 | } |
| 215 | |