chore(core): added @typescript-eslint/no-unnecessary-condition rule and removed redundant existence checks

packages/core/eslint.config.mjs

@@ -0,0 +1,10 @@
+import rootConfig from "../../eslint.config.mjs";
+
+export default [
+    ...rootConfig,
+    {
+        rules: {
+            "@typescript-eslint/no-unnecessary-condition": "error",
+        },
+    },
+];

packages/core/package.json

@@ -40,7 +40,7 @@
         "build": "tsc -b",
         "lint": "eslint .",
         "lint:fix": "eslint . --fix",
-        "format": "prettier --write \"src/**/*.ts\" \"test/**/*.ts\" \"**/*.json\"",
+        "format": "prettier --write \"src/**/*.ts\" \"test/**/*.ts\" \"**/*.json\" \"*.mjs\"",
         "test": "mocha --require ts-node/register --extension ts"
     },
     "bugs": {
@@ -50,8 +50,5 @@
     "directories": {
         "test": "test"
     },
-    "keywords": [],
-    "eslintConfig": {
-        "extends": "../../.eslintrc.js"
-    }
+    "keywords": []
 }

packages/core/src/codecs/octetstream-codec.ts

@@ -108,7 +108,7 @@ export default class OctetstreamCodec implements ContentCodec {
             if (typeSem) {
                 if (typeSem[1] === "u") {
                     // compare with schema information
-                    if (parameters?.signed === "true") {
+                    if (parameters.signed === "true") {
                         throw new Error("Type is unsigned but 'signed' is true");
                     }
                     // no schema, but type is unsigned
@@ -117,7 +117,7 @@ export default class OctetstreamCodec implements ContentCodec {
                 dataType = typeSem[2];
                 if (parseInt(typeSem[3]) !== bitLength) {
                     throw new Error(
-                        `Type is '${(typeSem[1] ?? "") + typeSem[2] + typeSem[3]}' but 'ex:bitLength' is ` + bitLength
+                        `Type is '${(typeSem[1] || "") + typeSem[2] + typeSem[3]}' but 'ex:bitLength' is ` + bitLength
                     );
                 }
             }
@@ -130,11 +130,11 @@ export default class OctetstreamCodec implements ContentCodec {
         }
 
         // Handle byte swapping
-        if (parameters?.byteSeq?.includes("BYTE_SWAP") === true && bytes.length > 1) {
+        if (parameters.byteSeq?.includes("BYTE_SWAP") === true && bytes.length > 1) {
             bytes.swap16();
         }
 
-        if (offset !== undefined && bitLength < bytes.length * 8) {
+        if (bitLength < bytes.length * 8) {
             bytes = this.readBits(bytes, offset, bitLength);
             bitLength = bytes.length * 8;
         }
@@ -282,7 +282,7 @@ export default class OctetstreamCodec implements ContentCodec {
             throw new Error("'ex:bitOffset' must be a non-negative number");
         }
 
-        let dataType: string = schema?.type ?? undefined;
+        let dataType: string | undefined = schema?.type;
 
         if (value === undefined) {
             throw new Error("Undefined value");
@@ -300,7 +300,7 @@ export default class OctetstreamCodec implements ContentCodec {
             if (typeSem) {
                 if (typeSem[1] === "u") {
                     // compare with schema information
-                    if (parameters?.signed === "true") {
+                    if (parameters.signed === "true") {
                         throw new Error("Type is unsigned but 'signed' is true");
                     }
                     // no schema, but type is unsigned
@@ -310,7 +310,7 @@ export default class OctetstreamCodec implements ContentCodec {
                 if (bitLength !== undefined) {
                     if (parseInt(typeSem[3]) !== bitLength) {
                         throw new Error(
-                            `Type is '${(typeSem[1] ?? "") + typeSem[2] + typeSem[3]}' but 'ex:bitLength' is ` +
+                            `Type is '${(typeSem[1] || "") + typeSem[2] + typeSem[3]}' but 'ex:bitLength' is ` +
                                 bitLength
                         );
                     }
@@ -446,7 +446,7 @@ export default class OctetstreamCodec implements ContentCodec {
         }
         // Handle byte swapping
 
-        if (byteSeq?.includes("BYTE_SwAP") && byteLength > 1) {
+        if (byteSeq.includes("BYTE_SwAP") && byteLength > 1) {
             buf.swap16();
         }
         switch (byteLength) {
@@ -584,7 +584,7 @@ export default class OctetstreamCodec implements ContentCodec {
         parameters: { [key: string]: string | undefined } = {},
         result?: Buffer | undefined
     ): Buffer {
-        if (typeof value !== "object" || value === null) {
+        if (typeof value !== "object") {
             throw new Error("Value is not an object");
         }
 

packages/core/src/consumed-thing.ts

@@ -130,8 +130,8 @@ class InternalPropertySubscription extends InternalSubscription {
         private readonly form: FormElementProperty
     ) {
         super(thing, name, client);
-        const index = this.thing.properties?.[name].forms.indexOf(form as Form);
-        if (index === undefined || index < 0) {
+        const index = this.thing.properties[name].forms.indexOf(form as Form);
+        if (index < 0) {
             throw new Error(`Could not find form ${form.href} in property ${name}`);
         }
         this.formIndex = index;
@@ -144,9 +144,6 @@ class InternalPropertySubscription extends InternalSubscription {
 
     public async unobserveProperty(options: WoT.InteractionOptions = {}): Promise<void> {
         const tp = this.thing.properties[this.name];
-        if (tp == null) {
-            throw new Error(`ConsumedThing '${this.thing.title}' does not have property ${this.name}`);
-        }
         options.formIndex ??= this.matchingUnsubscribeForm();
         const { form } = this.thing.getClientFor(tp.forms, "unobserveproperty", Affordance.PropertyAffordance, options);
         if (form == null) {
@@ -195,7 +192,7 @@ class InternalPropertySubscription extends InternalSubscription {
         for (let i = 0; i < forms.length; i++) {
             let score = 0;
             const form = forms[i];
-            if (form.op === operation || (form?.op?.includes(operation) === true && Array.isArray(form.op) === true)) {
+            if (form.op === operation || (form.op?.includes(operation) === true && Array.isArray(form.op) === true)) {
                 score += 1;
             }
 
@@ -232,7 +229,7 @@ function findFormIndexWithScoring(
     for (let i = 0; i < forms.length; i++) {
         let score = 0;
         const form = forms[i];
-        if (form.op === operation || (form?.op?.includes(operation) === true && Array.isArray(form.op) === true)) {
+        if (form.op === operation || (form.op?.includes(operation) === true && Array.isArray(form.op) === true)) {
             score += 1;
         }
 
@@ -261,8 +258,8 @@ class InternalEventSubscription extends InternalSubscription {
         private readonly form: FormElementEvent
     ) {
         super(thing, name, client);
-        const index = this.thing.events?.[name].forms.indexOf(form as Form);
-        if (index === undefined || index < 0) {
+        const index = this.thing.events[name].forms.indexOf(form as Form);
+        if (index < 0) {
             throw new Error(`Could not find form ${form.href} in event ${name}`);
         }
         this.formIndex = index;
@@ -275,9 +272,6 @@ class InternalEventSubscription extends InternalSubscription {
 
     public async unsubscribeEvent(options: WoT.InteractionOptions = {}): Promise<void> {
         const te = this.thing.events[this.name];
-        if (te == null) {
-            throw new Error(`ConsumedThing '${this.thing.title}' does not have event ${this.name}`);
-        }
 
         options.formIndex ??= this.matchingUnsubscribeForm();
 
@@ -461,7 +455,7 @@ export default class ConsumedThing extends Thing implements IConsumedThing {
 
                 let ws: SecurityScheme | undefined = this.securityDefinitions[s];
                 // also push nosec in case of proxy
-                if (ws?.scheme === "combo") {
+                if (ws.scheme === "combo") {
                     ws = resolveComboScheme(ws as ComboSecurityScheme, s);
                 }
                 if (ws != null) {
@@ -476,23 +470,21 @@ export default class ConsumedThing extends Thing implements IConsumedThing {
     }
 
     ensureClientSecurity(client: ProtocolClient, form: Form | undefined): void {
-        if (this.securityDefinitions != null) {
-            const logStatement = () =>
-                debug(`ConsumedThing '${this.title}' setting credentials for ${client} based on thing security`);
-
-            if (form != null && Array.isArray(form.security) && form.security.length > 0) {
-                // Note security member in form objects overrides (i.e., completely replace) all definitions activated at the Thing level
-                // see https://www.w3.org/TR/wot-thing-description/#security-serialization-json
-
-                logStatement();
-                client.setSecurity(this.getSecuritySchemes(form.security), this.#servient.retrieveCredentials(this.id));
-            } else if (Array.isArray(this.security) && this.security.length > 0) {
-                logStatement();
-                client.setSecurity(
-                    this.getSecuritySchemes(this.security as string[]),
-                    this.#servient.getCredentials(this.id)
-                );
-            }
+        const logStatement = () =>
+            debug(`ConsumedThing '${this.title}' setting credentials for ${client} based on thing security`);
+
+        if (form != null && Array.isArray(form.security) && form.security.length > 0) {
+            // Note security member in form objects overrides (i.e., completely replace) all definitions activated at the Thing level
+            // see https://www.w3.org/TR/wot-thing-description/#security-serialization-json
+
+            logStatement();
+            client.setSecurity(this.getSecuritySchemes(form.security), this.#servient.retrieveCredentials(this.id));
+        } else if (Array.isArray(this.security) && this.security.length > 0) {
+            logStatement();
+            client.setSecurity(
+                this.getSecuritySchemes(this.security as string[]),
+                this.#servient.getCredentials(this.id)
+            );
         }
     }
 
@@ -566,17 +558,12 @@ export default class ConsumedThing extends Thing implements IConsumedThing {
     async readProperty(propertyName: string, options?: WoT.InteractionOptions): Promise<WoT.InteractionOutput> {
         // TODO pass expected form op to getClientFor()
         const tp = this.properties[propertyName];
-        if (tp == null) {
-            throw new Error(`ConsumedThing '${this.title}' does not have property ${propertyName}`);
-        }
 
         const { client, form } = this.getClientFor(tp.forms, "readproperty", Affordance.PropertyAffordance, options);
         if (form == null) {
             throw new Error(`ConsumedThing '${this.title}' did not get suitable form`);
         }
-        if (client == null) {
-            throw new Error(`ConsumedThing '${this.title}' did not get suitable client for ${form.href}`);
-        }
+
         debug(`ConsumedThing '${this.title}' reading ${form.href}`);
 
         // uriVariables ?
@@ -597,7 +584,7 @@ export default class ConsumedThing extends Thing implements IConsumedThing {
         outputDataSchema: WoT.DataSchema | undefined
     ): InteractionOutput {
         // infer media type from form if not in response metadata
-        content.type ??= form.contentType ?? "application/json";
+        content.type = form.contentType ?? "application/json";
         // check if returned media type is the same as expected media type (from TD)
         this.checkMediaTypeOrThrow(content, form);
         return new InteractionOutput(content, form, outputDataSchema);
@@ -623,7 +610,7 @@ export default class ConsumedThing extends Thing implements IConsumedThing {
         synchronous?: boolean
     ): ActionInteractionOutput {
         // infer media type from form if not in response metadata
-        content.type ??= form.contentType ?? "application/json";
+        content.type = form.contentType ?? "application/json";
         // check if returned media type is the same as expected media type (from TD)
         this.checkMediaTypeOrThrow(content, form);
         return new ActionInteractionOutput(content, form, outputDataSchema, synchronous);
@@ -677,16 +664,10 @@ export default class ConsumedThing extends Thing implements IConsumedThing {
     ): Promise<void> {
         // TODO pass expected form op to getClientFor()
         const tp = this.properties[propertyName];
-        if (tp == null) {
-            throw new Error(`ConsumedThing '${this.title}' does not have property ${propertyName}`);
-        }
         const { client, form } = this.getClientFor(tp.forms, "writeproperty", Affordance.PropertyAffordance, options);
         if (form == null) {
             throw new Error(`ConsumedThing '${this.title}' did not get suitable form`);
         }
-        if (client == null) {
-            throw new Error(`ConsumedThing '${this.title}' did not get suitable client for ${form.href}`);
-        }
         debug(`ConsumedThing '${this.title}' writing ${form.href} with '${value}'`);
 
         const content = ContentManager.valueToContent(value, tp, form.contentType);
@@ -718,16 +699,10 @@ export default class ConsumedThing extends Thing implements IConsumedThing {
         options?: WoT.InteractionOptions
     ): Promise<WoT.ActionInteractionOutput> {
         const ta = this.actions[actionName];
-        if (ta == null) {
-            throw new Error(`ConsumedThing '${this.title}' does not have action ${actionName}`);
-        }
         const { client, form } = this.getClientFor(ta.forms, "invokeaction", Affordance.ActionAffordance, options);
         if (form == null) {
             throw new Error(`ConsumedThing '${this.title}' did not get suitable form`);
         }
-        if (client == null) {
-            throw new Error(`ConsumedThing '${this.title}' did not get suitable client for ${form.href}`);
-        }
         debug(
             `ConsumedThing '${this.title}' invoking ${form.href}${
                 parameter !== undefined ? " with '" + parameter + "'" : ""
@@ -763,16 +738,10 @@ export default class ConsumedThing extends Thing implements IConsumedThing {
         options?: WoT.InteractionOptions
     ): Promise<Subscription> {
         const tp = this.properties[name];
-        if (tp == null) {
-            throw new Error(`ConsumedThing '${this.title}' does not have property ${name}`);
-        }
         const { client, form } = this.getClientFor(tp.forms, "observeproperty", Affordance.PropertyAffordance, options);
         if (form == null) {
             throw new Error(`ConsumedThing '${this.title}' did not get suitable form`);
         }
-        if (client == null) {
-            throw new Error(`ConsumedThing '${this.title}' did not get suitable client for ${form.href}`);
-        }
         if (this.observedProperties.has(name)) {
             throw new Error(
                 `ConsumedThing '${this.title}' has already a function subscribed to ${name}. You can only observe once`
@@ -820,16 +789,10 @@ export default class ConsumedThing extends Thing implements IConsumedThing {
         options?: WoT.InteractionOptions
     ): Promise<Subscription> {
         const te = this.events[name];
-        if (te == null) {
-            throw new Error(`ConsumedThing '${this.title}' does not have event ${name}`);
-        }
         const { client, form } = this.getClientFor(te.forms, "subscribeevent", Affordance.EventAffordance, options);
         if (form == null) {
             throw new Error(`ConsumedThing '${this.title}' did not get suitable form`);
         }
-        if (client == null) {
-            throw new Error(`ConsumedThing '${this.title}' did not get suitable client for ${form.href}`);
-        }
         if (this.subscribedEvents.has(name)) {
             throw new Error(
                 `ConsumedThing '${this.title}' has already a function subscribed to ${name}. You can only subscribe once`

packages/core/src/content-serdes.ts

@@ -47,7 +47,7 @@ interface ReadContent {
  * it can accept multiple serializers and decoders
  */
 export class ContentSerdes {
-    private static instance: ContentSerdes;
+    private static instance: ContentSerdes | undefined;
 
     public static readonly DEFAULT: string = "application/json";
     public static readonly TD: string = "application/td+json";
@@ -57,7 +57,7 @@ export class ContentSerdes {
     private offered: Set<string> = new Set<string>();
 
     public static get(): ContentSerdes {
-        if (this.instance == null) {
+        if (!this.instance) {
             this.instance = new ContentSerdes();
             // JSON
             this.instance.addCodec(new JsonCodec(), true);
@@ -126,14 +126,12 @@ export class ContentSerdes {
     }
 
     public contentToValue(content: ReadContent, schema: DataSchema): DataSchemaValue | undefined {
-        if (content.type === undefined) {
-            if (content.body.byteLength > 0) {
-                // default to application/json
-                content.type = ContentSerdes.DEFAULT;
-            } else {
-                // empty payload without media type -> void/undefined (note: e.g., empty payload with text/plain -> "")
-                return undefined;
-            }
+        if (content.body.byteLength > 0) {
+            // default to application/json
+            content.type = ContentSerdes.DEFAULT;
+        } else {
+            // empty payload without media type -> void/undefined (note: e.g., empty payload with text/plain -> "")
+            return undefined;
         }
 
         // split into media type and parameters
@@ -162,8 +160,6 @@ export class ContentSerdes {
         schema: DataSchema | undefined,
         contentType = ContentSerdes.DEFAULT
     ): Content {
-        if (value === undefined) warn("ContentSerdes valueToContent got no value");
-
         if (value instanceof ReadableStream) {
             return new Content(contentType, ProtocolHelpers.toNodeStream(value));
         }