Merge pull request #113 from ehn-dcc-development/feature/dob

[CertLogic] add operation for dealing with (partial) DOBs

certlogic/certlogic-js/CHANGELOG.md

@@ -1,10 +1,31 @@
 # Change log
 
+## 1.2.0
+
+* Add a `dccDateOfBirth` operation to convert date of birth (DOB) values in the EU DCC to a date.
+  Such DOBs may be “partial dates” of the form YYYY or YYYY-MM.
+  See [the specification](../specification/README.md#) for more details.
+
+* Changed desugaring of `"or"` (in the `misc` sub package) to align semantically with that of the `"and"` operation:
+  the first truthy operand is returned, or the last operand (which is then falsy).
+  This replaces the semantics where a desugared `"or"` always returned a boolean value, due to the use of [De Morgan's laws](https://en.wikipedia.org/wiki/De_Morgan%27s_laws).
+  (Also: an `"or"` with a single operand reduces to that operand.)
+
+* Build improvement: perform deduplication of (nested) dependencies.
+
+* Added the following to the `internals`:
+  * The concept of “boolsiness” (internally) by means of a type `Boolsiness` and a function `boolsiness`.
+  * A `CertlogicLiteral` type, and a corresponding type guard function.
+
+  These can be imported (until they're re-exported by `index.ts`) as `import { ... } from "certlogic-js/dist/internals"`.
+
+
 ## 1.1.2
 
 * Improve types in source of `renderAsCompactText`
 * (fix:) Really prevent emission of all source map files, not just for the `.d.ts`-files
-* Replace use of `Object.keys(...)` with equivalent use of `Object.entries(...)` - shorter code; maybe some performance improvement?
+* Replace use of `Object.keys(...)` with equivalent use of `Object.entries(...)`.
+  Advantage: shorter code, and maybe some performance improvement?
 
 
 ## 1.1.1

certlogic/certlogic-js/README.md

@@ -4,7 +4,7 @@
 It is a [specified](https://github.com/ehn-dcc-development/dgc-business-rules/blob/main/certlogic/specification/README.md) subset of [JsonLogic](https://jsonlogic.com/), extended with necessary custom operations - e.g. for working with dates.
 It's part of the efforts surrounding the [Digital COVID Certificate](https://ec.europa.eu/info/live-work-travel-eu/coronavirus-response/safe-covid-19-vaccines-europeans/eu-digital-covid-certificate_en), and as such serves as the basis for defining _interchangeable_ validation rules on top of the DCC.
 
-This NPM package consists of an implementation of CertLogic in JavaScript(/TypeScript) which is compatible with version **1.2.4** of [the specification](https://github.com/ehn-dcc-development/dgc-business-rules/tree/main/certlogic/specification/README.md).
+This NPM package consists of an implementation of CertLogic in JavaScript(/TypeScript) which is compatible with version **1.3.0** of [the specification](https://github.com/ehn-dcc-development/dgc-business-rules/tree/main/certlogic/specification/README.md).
 
 
 ## API

certlogic/certlogic-js/build.sh

@@ -4,6 +4,7 @@ set -e
 
 npm run clean
 npm install
+npm dedupe # also deduplicate dependencies
 npm test  # also builds the source
 
 # check for circular dependencies, and exit in case one's present:

certlogic/certlogic-js/package.json

@@ -1,6 +1,6 @@
 {
   "name": "certlogic-js",
-  "version": "1.1.2",
+  "version": "1.2.0",
   "description": "Implementation of CertLogic in TypeScript",
   "keywords": [
     "json",
@@ -44,10 +44,12 @@
   "devDependencies": {
     "@types/chai": "^4.3.0",
     "@types/mocha": "^9.1.0",
-    "@types/node": "^17.0.14",
+    "@types/node": "^17.0.17",
+    "@types/semver": "^7.3.9",
     "chai": "^4.3.6",
     "dpdm": "^3.8.0",
     "mocha": "^9.2.0",
+    "semver": "^7.3.5",
     "typescript": "^4.5.5"
   }
 }

certlogic/certlogic-js/src/evaluator.ts

@@ -1,10 +1,8 @@
 import { CertLogicExpression, TimeUnit, timeUnits } from "./typings"
 import {
-    access,
-    extractFromUVCI,
-    isFalsy,
+    access, boolsiness, dccDateOfBirth,
+    extractFromUVCI, isCertLogicLiteral,
     isInt,
-    isTruthy,
     plusTime
 } from "./internals"
 
@@ -28,13 +26,11 @@ const evaluateIf = (guard: CertLogicExpression, then: CertLogicExpression, else_
         throw new Error(`an if-operation must have an else (argument #3)`)
     }
     const evalGuard = evaluate(guard, data)
-    if (isTruthy(evalGuard)) {
-        return evaluate(then, data)
+    switch (boolsiness(evalGuard)) {
+        case true: return evaluate(then, data)
+        case false: return evaluate(else_, data)
+        case undefined: throw new Error(`if-guard evaluates to something neither truthy, nor falsy: ${evalGuard}`)
     }
-    if (isFalsy(evalGuard)) {
-        return evaluate(else_, data)
-    }
-    throw new Error(`if-guard evaluates to something neither truthy, nor falsy: ${evalGuard}`)
 }
 
 
@@ -111,13 +107,11 @@ const evaluateInfix = (operator: string, values: CertLogicExpression[], data: an
         }
         case "and": return values.reduce(
             (acc: any, current: CertLogicExpression) => {
-                if (isFalsy(acc)) {
-                    return acc
-                }
-                if (isTruthy(acc)) {
-                    return evaluate(current, data)
+                switch (boolsiness(acc)) {
+                    case false: return acc
+                    case true: return evaluate(current, data)
+                    case undefined: throw new Error(`all operands of an "and" operation must be either truthy or falsy`)
                 }
-                throw new Error(`all operands of an "and" operation must be either truthy or falsy`)
             },
             true
         )
@@ -146,13 +140,11 @@ const evaluateInfix = (operator: string, values: CertLogicExpression[], data: an
 
 const evaluateNot = (operand: CertLogicExpression, data: any): any => {
     const evalOperand = evaluate(operand, data)
-    if (isFalsy(evalOperand)) {
-        return true
-    }
-    if (isTruthy(evalOperand)) {
-        return false
+    switch (boolsiness(evalOperand)) {
+        case false: return true
+        case true: return false
+        case undefined: throw new Error(`operand of ! evaluates to something neither truthy, nor falsy: ${evalOperand}`)
     }
-    throw new Error(`operand of ! evaluates to something neither truthy, nor falsy: ${evalOperand}`)
 }
 
 
@@ -165,7 +157,7 @@ const evaluatePlusTime = (dateOperand: CertLogicExpression, amount: CertLogicExp
     }
     const dateTimeStr = evaluate(dateOperand, data)
     if (typeof dateTimeStr !== "string") {
-        throw new Error(`date argument of "plusTime" must be a string`)
+        throw new Error(`date argument (#1) of "plusTime" must be a string`)
     }
     return plusTime(dateTimeStr, amount, unit)
 }
@@ -200,8 +192,17 @@ const evaluateExtractFromUVCI = (operand: CertLogicExpression, index: number, da
 }
 
 
+const evaluateDccDateOfBirth = (operand: CertLogicExpression, data: any): Date => {
+    const evalOperand = evaluate(operand, data)
+    if (!(typeof evalOperand === "string")) {
+        throw new Error(`operand of "dccDateOfBirth" must be a string`)
+    }
+    return dccDateOfBirth(evalOperand)
+}
+
+
 export const evaluate = (expr: CertLogicExpression, data: any): any => {
-    if (typeof expr === "string" || isInt(expr) || typeof expr === "boolean") {
+    if (isCertLogicLiteral(expr)) {
         return expr
     }
     if (expr === null) {
@@ -241,6 +242,9 @@ export const evaluate = (expr: CertLogicExpression, data: any): any => {
         if (operator === "extractFromUVCI") {
             return evaluateExtractFromUVCI(values[0], values[1], data)
         }
+        if (operator === "dccDateOfBirth") {
+            return evaluateDccDateOfBirth(values[0], data)
+        }
         throw new Error(`unrecognised operator: "${operator}"`)
     }
     throw new Error(`invalid CertLogic expression: ${expr}`)

certlogic/certlogic-js/src/factories.ts

@@ -33,3 +33,6 @@ export const reduce_ = (operand: CertLogicExpression, lambda: CertLogicExpressio
 export const extractFromUVCI_ = (operand: CertLogicExpression, index: number): CertLogicOperation =>
     ({ "extractFromUVCI": [ operand, index ] })
 
+export const dccDateOfBirth_ = (operand: CertLogicExpression): CertLogicOperation =>
+    ({ "dccDateOfBirth": [ operand ] })
+