feat: deduplicate locations on insert

plugins/catalog-backend/package.json

@@ -21,6 +21,7 @@
     "helmet": "^3.22.0",
     "knex": "^0.21.1",
     "morgan": "^1.10.0",
+    "sqlite3": "^4.2.0",
     "uuid": "^8.0.0",
     "winston": "^3.2.1",
     "yaml": "^1.9.2",

plugins/catalog-backend/src/catalog/DatabaseCatalog.test.ts

@@ -60,4 +60,20 @@ describe('DatabaseCatalog', () => {
       /Found no location/,
     );
   });
+
+  it('instead of adding second location with the same target, returns existing one', async () => {
+    // Prepare
+    const catalog = new DatabaseCatalog(database, logger);
+    const input = { type: 'a', target: 'b' };
+    const output1 = await catalog.addLocation(input);
+
+    // Try to insert the same location
+    const output2 = await catalog.addLocation(input);
+    const locations = await catalog.locations();
+
+    // Output is the same
+    expect(output2).toEqual(output1);
+    // Locations contain only one record
+    expect(locations).toEqual([output1]);
+  });
 });

plugins/catalog-backend/src/catalog/DatabaseCatalog.ts

@@ -53,7 +53,7 @@ export class DatabaseCatalog implements Catalog {
       name: descriptor.metadata.name,
     };
 
-    await this.database.transaction(async (tx) => {
+    await this.database.transaction(async tx => {
       // TODO(freben): Currently, several locations can compete for the same component
       const count = await tx('components')
         .where({ name: component.name })
@@ -74,7 +74,9 @@ export class DatabaseCatalog implements Catalog {
 
   // eslint-disable-next-line @typescript-eslint/no-unused-vars
   async component(name: string): Promise<Component> {
-    const items = await this.database('components').where({ name }).select();
+    const items = await this.database('components')
+      .where({ name })
+      .select();
     if (!items.length) {
       throw new NotFoundError(`Found no component with name ${name}`);
     }
@@ -82,6 +84,10 @@ export class DatabaseCatalog implements Catalog {
   }
 
   async addLocation(location: AddLocationRequest): Promise<Location> {
+    const existingLocation = await this.locationByTarget(location.target);
+    if (existingLocation) {
+      return existingLocation;
+    }
     const id = uuidv4();
     const { type, target } = location;
     await this.database('locations').insert({ id, type, target });
@@ -89,7 +95,9 @@ export class DatabaseCatalog implements Catalog {
   }
 
   async removeLocation(id: string): Promise<void> {
-    const result = await this.database('locations').where({ id }).del();
+    const result = await this.database('locations')
+      .where({ id })
+      .del();
 
     if (!result) {
       throw new NotFoundError(`Found no location with ID ${id}`);
@@ -97,13 +105,21 @@ export class DatabaseCatalog implements Catalog {
   }
 
   async location(id: string): Promise<Location> {
-    const items = await this.database('locations').where({ id }).select();
+    const items = await this.database('locations')
+      .where({ id })
+      .select();
     if (!items.length) {
       throw new NotFoundError(`Found no location with ID ${id}`);
     }
     return items[0];
   }
 
+  private async locationByTarget(
+    target: string,
+  ): Promise<Location | undefined> {
+    return (await this.locations()).find(l => l.target === target);
+  }
+
   async locations(): Promise<Location[]> {
     return await this.database('locations').select();
   }