simplify Recipe API, add flow control checks to node API

src/core/Chef.mjs

@@ -39,12 +39,14 @@ class Chef {
     */
     async bake(input, recipeConfig, options) {
         log.debug("Chef baking");
-        const startTime = Date.now(),
+
-            recipe      = new Recipe(recipeConfig),
+        const startTime     = Date.now();
-            containsFc  = recipe.containsFlowControl(),
+        const recipe        = await Recipe.buildRecipe(recipeConfig);
-            notUTF8     = options && "treatAsUtf8" in options && !options.treatAsUtf8;
+        const containsFc    = recipe.state.containsFlowControl();
-        let error = false,
+        const notUTF8       = options && "treatAsUtf8" in options && !options.treatAsUtf8;
-            progress = 0;
+
+        let error = false;
+        let progress = 0;
 
         if (containsFc && isWorkerEnvironment()) self.setOption("attemptHighlight", false);
 
@@ -53,7 +55,7 @@ class Chef {
         this.dish.set(input, type);
 
         try {
-            progress = await recipe.execute(this.dish, progress);
+            progress = await recipe.execute(this.dish);
         } catch (err) {
             log.error(err);
             error = {
@@ -107,12 +109,12 @@ class Chef {
      * @param {Object[]} recipeConfig - The recipe configuration object
      * @returns {number} The time it took to run the silent bake in milliseconds.
     */
-    silentBake(recipeConfig) {
+    async silentBake(recipeConfig) {
         log.debug("Running silent bake");
 
-        const startTime = Date.now(),
+        const startTime = Date.now();
-            recipe = new Recipe(recipeConfig),
+        const recipe    = await Recipe.buildRecipe(recipeConfig);
-            dish = new Dish();
+        const dish      = new Dish();
 
         try {
             recipe.execute(dish);
@@ -134,8 +136,8 @@ class Chef {
      * @returns {Object}
      */
     async calculateHighlights(recipeConfig, direction, pos) {
-        const recipe = new Recipe(recipeConfig);
+        const recipe = await Recipe.buildRecipe(recipeConfig);
-        const highlights = await recipe.generateHighlightList();
+        const highlights = recipe.generateHighlightList();
 
         if (!highlights) return false;
 

src/core/Recipe.mjs

@@ -24,69 +24,18 @@ class Recipe  {
      *
      * @param {Object} recipeConfig
      */
-    constructor(recipeConfig) {
+    constructor(operations=[]) {
-        this.opList = [];
+        this.state = new RecipeState();
-
+        this.state.opList = operations;
-        if (recipeConfig) {
-            this._parseConfig(recipeConfig);
-        }
     }
 
-
-    /**
-     * Reads and parses the given config.
-     *
-     * @private
-     * @param {Object} recipeConfig
-     */
-    _parseConfig(recipeConfig) {
-        recipeConfig.forEach(c => {
-            this.opList.push({
-                name: c.op,
-                module: OperationConfig[c.op].module,
-                ingValues: c.args,
-                breakpoint: c.breakpoint,
-                disabled: c.disabled,
-            });
-        });
-    }
-
-
-    /**
-     * Populate elements of opList with operation instances.
-     * Dynamic import here removes top-level cyclic dependency issue.
-     *
-     * @private
-     */
-    async _hydrateOpList() {
-        if (!modules) {
-            // Using Webpack Magic Comments to force the dynamic import to be included in the main chunk
-            // https://webpack.js.org/api/module-methods/
-            modules = await import(/* webpackMode: "eager" */ "./config/modules/OpModules.mjs");
-            modules = modules.default;
-        }
-
-        this.opList = this.opList.map(o => {
-            if (o instanceof Operation) {
-                return o;
-            } else {
-                const op = new modules[o.module][o.name]();
-                op.ingValues = o.ingValues;
-                op.breakpoint = o.breakpoint;
-                op.disabled = o.disabled;
-                return op;
-            }
-        });
-    }
-
-
     /**
      * Returns the value of the Recipe as it should be displayed in a recipe config.
      *
      * @returns {Object[]}
      */
     get config() {
-        return this.opList.map(op => ({
+        return this.state.opList.map(op => ({
             op: op.name,
             args: op.ingValues,
         }));
@@ -99,7 +48,7 @@ class Recipe  {
      * @param {Operation} operation
      */
     addOperation(operation) {
-        this.opList.push(operation);
+        this.state.addOperation(operation);
     }
 
 
@@ -110,85 +59,31 @@ class Recipe  {
      */
     addOperations(operations) {
         operations.forEach(o => {
-            if (o instanceof Operation) {
+            this.state.addOperation(o);
-                this.opList.push(o);
-            } else {
-                this.opList.push({
-                    name: o.name,
-                    module: o.module,
-                    ingValues: o.args,
-                    breakpoint: o.breakpoint,
-                    disabled: o.disabled,
-                });
-            }
         });
     }
 
 
-    /**
-     * Set a breakpoint on a specified Operation.
-     *
-     * @param {number} position - The index of the Operation
-     * @param {boolean} value
-     */
-    setBreakpoint(position, value) {
-        try {
-            this.opList[position].breakpoint = value;
-        } catch (err) {
-            // Ignore index error
-        }
-    }
-
-
-    /**
-     * Remove breakpoints on all Operations in the Recipe up to the specified position. Used by Flow
-     * Control Fork operation.
-     *
-     * @param {number} pos
-     */
-    removeBreaksUpTo(pos) {
-        for (let i = 0; i < pos; i++) {
-            this.opList[i].breakpoint = false;
-        }
-    }
-
-
-    /**
-     * Returns true if there is a Flow Control Operation in this Recipe.
-     *
-     * @returns {boolean}
-     */
-    containsFlowControl() {
-        return this.opList.reduce((acc, curr) => {
-            return acc || curr.flowControl;
-        }, false);
-    }
-
-
     /**
      * Executes each operation in the recipe over the given Dish.
      *
      * @param {Dish} dish
-     * @param {number} [startFrom=0]
-     *     - The index of the Operation to start executing from
      * @param {number} [forkState={}]
      *     - If this is a forked recipe, the state of the recipe up to this point
      * @returns {number}
      *     - The final progress through the recipe
      */
-    async execute(dish, startFrom=0, forkState={}) {
+    async execute(dish, forkState={}) {
-        let op, input, output,
+        let op, input, output;
-            numJumps = 0,
+        this.state.dish = dish;
-            numRegisters = forkState.numRegisters || 0;
+        this.state.updateForkState(forkState);
+        this.lastRunOp = null;
 
-        if (startFrom === 0) this.lastRunOp = null;
+        log.debug(`[*] Executing recipe of ${this.state.opList.length} operations`);
 
-        await this._hydrateOpList();
+        while (this.state.progress < this.state.opList.length) {
-
+            const i = this.state.progress;
-        log.debug(`[*] Executing recipe of ${this.opList.length} operations, starting at ${startFrom}`);
+            op = this.state.currentOp;
-
-        for (let i = startFrom; i < this.opList.length; i++) {
-            op = this.opList[i];
             log.debug(`[${i}] ${op.name} ${JSON.stringify(op.ingValues)}`);
             if (op.disabled) {
                 log.debug("Operation is disabled, skipping");
@@ -200,32 +95,21 @@ class Recipe  {
             }
 
             try {
-                input = await dish.get(op.inputType);
+                input = await this.state.dish.get(op.inputType);
                 log.debug(`Executing operation '${op.name}'`);
 
                 if (isWorkerEnvironment()) {
-                    self.sendStatusMessage(`Baking... (${i+1}/${this.opList.length})`);
+                    self.sendStatusMessage(`Baking... (${i+1}/${this.state.opList.length})`);
-                    self.sendProgressMessage(i + 1, this.opList.length);
+                    self.sendProgressMessage(i + 1, this.state.opList.length);
                 }
 
                 if (op.flowControl) {
-                    // Package up the current state
+                    this.state = await op.run(this.state);
-                    let state = {
+                    this.state.progress++;
-                        "progress":     i,
-                        "dish":         dish,
-                        "opList":       this.opList,
-                        "numJumps":     numJumps,
-                        "numRegisters": numRegisters,
-                        "forkOffset":   forkState.forkOffset || 0
-                    };
-
-                    state = await op.run(state);
-                    i = state.progress;
-                    numJumps = state.numJumps;
-                    numRegisters = state.numRegisters;
                 } else {
                     output = await op.run(input, op.ingValues);
-                    dish.set(output, op.outputType);
+                    this.state.dish.set(output, op.outputType);
+                    this.state.progress++;
                 }
                 this.lastRunOp = op;
             } catch (err) {
@@ -234,11 +118,11 @@ class Recipe  {
                     (err.type && err.type === "OperationError")) {
                     // Cannot rely on `err instanceof OperationError` here as extending
                     // native types is not fully supported yet.
-                    dish.set(err.message, "string");
+                    this.state.dish.set(err.message, "string");
                     return i;
                 } else if (err instanceof DishError ||
                     (err.type && err.type === "DishError")) {
-                    dish.set(err.message, "string");
+                    this.state.dish.set(err.message, "string");
                     return i;
                 } else {
                     const e = typeof err == "string" ? { message: err } : err;
@@ -257,7 +141,7 @@ class Recipe  {
         }
 
         log.debug("Recipe complete");
-        return this.opList.length;
+        return this.state.opList.length;
     }
 
 
@@ -287,17 +171,6 @@ class Recipe  {
     }
 
 
-    /**
-     * Creates a Recipe from a given configuration string.
-     *
-     * @param {string} recipeStr
-     */
-    fromString(recipeStr) {
-        const recipeConfig = JSON.parse(recipeStr);
-        this._parseConfig(recipeConfig);
-    }
-
-
     /**
      * Generates a list of all the highlight functions assigned to operations in the recipe, if the
      * entire recipe supports highlighting.
@@ -307,13 +180,15 @@ class Recipe  {
      * @returns {function} highlights[].b
      * @returns {Object[]} highlights[].args
      */
-    async generateHighlightList() {
+    generateHighlightList() {
-        await this._hydrateOpList();
         const highlights = [];
-
+        while (this.state.progress < this.state.opList.length) {
-        for (let i = 0; i < this.opList.length; i++) {
+        // for (let i = 0; i < this.state.opList.length; i++) {
-            const op = this.opList[i];
+            const op = this.state.currentOp;
-            if (op.disabled) continue;
+            if (op.disabled) {
+                this.state.progress++;
+                continue;
+            }
 
             // If any breakpoints are set, do not attempt to highlight
             if (op.breakpoint) return false;
@@ -333,16 +208,120 @@ class Recipe  {
 
 
     /**
-     * Determines whether the previous operation has a different presentation type to its normal output.
+     * Build a recipe using a recipeConfig
      *
-     * @param {number} progress
+     * Hydrate the recipeConfig before using the hydrated operations
-     * @returns {boolean}
+     * in the Recipe constructor. This decouples the hydration of
+     * the operations from the Recipe logic.
+     *
+     * @param {recipeConfig} recipeConfig
      */
-    lastOpPresented(progress) {
+    static async buildRecipe(recipeConfig) {
-        if (progress < 1) return false;
+        const operations = [];
-        return this.opList[progress-1].presentType !== this.opList[progress-1].outputType;
+        recipeConfig.forEach(c => {
+            operations.push({
+                name: c.op,
+                module: OperationConfig[c.op].module,
+                ingValues: c.args,
+                breakpoint: c.breakpoint,
+                disabled: c.disabled,
+            });
+        });
+
+        if (!modules) {
+            // Using Webpack Magic Comments to force the dynamic import to be included in the main chunk
+            // https://webpack.js.org/api/module-methods/
+            modules = await import(/* webpackMode: "eager" */ "./config/modules/OpModules.mjs");
+            modules = modules.default;
+        }
+
+        const hydratedOperations = operations.map(o => {
+            if (o instanceof Operation) {
+                return o;
+            } else {
+                const op = new modules[o.module][o.name]();
+                op.ingValues = o.ingValues;
+                op.breakpoint = o.breakpoint;
+                op.disabled = o.disabled;
+                return op;
+            }
+        });
+
+        return new Recipe(hydratedOperations);
     }
 
 }
 
+
+/**
+ * Encapsulate the state of a Recipe
+ *
+ * Encapsulating the state makes it cleaner when passing the state
+ * between operations.
+ */
+class RecipeState {
+
+    /**
+     * initialise a RecipeState
+     */
+    constructor() {
+        this.dish = null;
+        this.opList = [];
+        this.progress = 0;
+        this.forkOffset = 0;
+        this.numRegisters = 0;
+        this.numJumps = 0;
+    }
+
+    /**
+     * get the next operation due to be run.
+     * @return {Operation}
+     */
+    get currentOp() {
+        return this.opList[this.progress];
+    }
+
+    /**
+     * add an operation to the end of RecipeState's opList
+     * @param {Operation} operation
+     */
+    addOperation(operation) {
+        this.opList.push(operation);
+    }
+
+    /**
+     * @returns {boolean} whether there's a flowControl operation in
+     * the RecipeState's opList
+     */
+    containsFlowControl() {
+        return this.opList.reduce((p, c) => {
+            return p || c.flowControl;
+        }, false);
+    }
+
+    /**
+     * Update the RecipeState with state from a fork. Used at the end
+     * of the Fork operation.
+     * @param {Object} forkState
+     */
+    updateForkState(forkState) {
+        if (forkState.progress || forkState.progress === 0) {
+            this.progress = forkState.progress;
+        }
+
+        if (forkState.numRegisters || forkState.numRegisters === 0) {
+            this.numRegisters = forkState.numRegisters;
+        }
+
+        if (forkState.numJumps || forkState.numJumps === 0) {
+            this.numJumps = forkState.numJumps;
+        }
+
+        if (forkState.forkOffset || forkState.forkOffset === 0) {
+            this.forkOffset = forkState.forkOffset;
+        }
+    }
+}
+
 export default Recipe;
+export { RecipeState };

src/core/lib/Magic.mjs

@@ -449,11 +449,11 @@ class Magic {
 
         if (isWorkerEnvironment()) self.loadRequiredModules(recipeConfig);
 
-        const recipe = new Recipe(recipeConfig);
+        const recipe = await Recipe.buildRecipe(recipeConfig);
         try {
             await recipe.execute(dish);
             // Return an empty buffer if the recipe did not run to completion
-            if (recipe.lastRunOp === recipe.opList[recipe.opList.length - 1]) {
+            if (recipe.lastRunOp === recipe.state.opList[recipe.state.opList.length - 1]) {
                 return await dish.get(Dish.ARRAY_BUFFER);
             } else {
                 return new ArrayBuffer();

src/core/operations/Fork.mjs

@@ -89,7 +89,7 @@ class Fork extends Operation {
         // Run recipe over each tranche
         for (i = 0; i < inputs.length; i++) {
             // Baseline ing values for each tranche so that registers are reset
-            recipe.opList.forEach((op, i) => {
+            recipe.state.opList.forEach((op, i) => {
                 op.ingValues = JSON.parse(JSON.stringify(ingValues[i]));
             });
 
@@ -97,7 +97,7 @@ class Fork extends Operation {
             dish.set(inputs[i], inputType);
 
             try {
-                progress = await recipe.execute(dish, 0, state);
+                progress = await recipe.execute(dish, state);
             } catch (err) {
                 if (!ignoreErrors) {
                     throw err;

src/core/operations/Magic.mjs

@@ -112,9 +112,9 @@ class Magic extends Operation {
         options.forEach(option => {
             // Construct recipe URL
             // Replace this Magic op with the generated recipe
-            const recipeConfig = currentRecipeConfig.slice(0, this.state.progress)
+            const recipeConfig = currentRecipeConfig.slice(0, this.state.progress - 1)
                     .concat(option.recipe)
-                    .concat(currentRecipeConfig.slice(this.state.progress + 1)),
+                    .concat(currentRecipeConfig.slice(this.state.progress)),
                 recipeURL = "recipe=" + Utils.encodeURIFragment(Utils.generatePrettyRecipe(recipeConfig));
 
             let language = "",

src/core/operations/Subsection.mjs

@@ -115,7 +115,7 @@ class Subsection extends Operation {
                 }
 
                 // Baseline ing values for each tranche so that registers are reset
-                recipe.opList.forEach((op, i) => {
+                recipe.state.opList.forEach((op, i) => {
                     op.ingValues = JSON.parse(JSON.stringify(ingValues[i]));
                 });
 
@@ -123,7 +123,7 @@ class Subsection extends Operation {
                 dish.set(matchStr, inputType);
 
                 try {
-                    progress = await recipe.execute(dish, 0, state);
+                    progress = await recipe.execute(dish, state);
                 } catch (err) {
                     if (!ignoreErrors) {
                         throw err;

src/node/api.mjs

@@ -192,6 +192,7 @@ export function _wrap(OpClass) {
         wrapped = async (input, args=null) => {
             const {transformedInput, transformedArgs} = prepareOp(opInstance, input, args);
             const result = await opInstance.run(transformedInput, transformedArgs);
+
             return new NodeDish({
                 value: result,
                 type: opInstance.outputType,

tests/node/tests/operations.mjs

@@ -1075,6 +1075,5 @@ ExifImageHeight: 57`);
         assert.equal(output, res.value);
     }),
 
-
 ]);
 

tests/operations/index.mjs

@@ -79,7 +79,6 @@ import "./tests/StrUtils.mjs";
 import "./tests/SymmetricDifference.mjs";
 import "./tests/TextEncodingBruteForce.mjs";
 import "./tests/TranslateDateTimeFormat.mjs";
-import "./tests/Magic.mjs";
 import "./tests/ParseTLV.mjs";
 import "./tests/Media.mjs";
 import "./tests/ToFromInsensitiveRegex.mjs";