api interop layer: geometry tests

api-interop-layer/data/alerts/geometry.js

@@ -0,0 +1,72 @@
+const unwindGeometryCollection = (geojson, parentIsCollection = false) => {
+  if (geojson.type === "GeometryCollection") {
+    const geometries = geojson.geometries.flatMap((geometry) =>
+      unwindGeometryCollection(geometry, true),
+    );
+    if (parentIsCollection) {
+      return geometries;
+    }
+
+    geojson.geometries = geometries;
+    return geojson;
+  }
+
+  return geojson;
+};
+
+export const generateAlertGeometry = async (db, rawAlert) => {
+  // if the alert already has geometry, nothing to do
+  if (rawAlert.geometry) {
+    return unwindGeometryCollection(rawAlert.geometry);
+  }
+
+  // if we have affected zones, generate a geometry from zones
+  const zones = rawAlert.properties.affectedZones;
+  if (Array.isArray(zones) && zones.length > 0) {
+    const sql = `
+      SELECT ST_ASGEOJSON(
+        ST_SIMPLIFY(
+          ST_SRID(
+            ST_COLLECT(shape),
+            0
+          ),
+          0.003
+        )
+      )
+        AS shape
+        FROM weathergov_geo_zones
+        WHERE id IN (${zones.map(() => "?").join(",")})`;
+    const [{ shape }] = await db.query(sql, zones);
+    if (shape) {
+      return unwindGeometryCollection(shape);
+    }
+  }
+
+  // if all geocodes are the same, generate a geometry from geocodes
+  const counties = rawAlert.properties.geocode?.SAME;
+  if (Array.isArray(counties) && counties.length > 0) {
+    const sql = `
+      SELECT ST_ASGEOJSON(
+        ST_SIMPLIFY(
+          ST_SRID(
+            ST_COLLECT(shape),
+            0
+          ),
+          0.003
+        )
+      )
+        AS shape
+        FROM weathergov_geo_counties
+        WHERE countyFips IN (${counties.map((c) => `'${c.slice(1)}'`).join(",")})`;
+    const [{ shape }] = await db.query(sql);
+
+    if (shape) {
+      return unwindGeometryCollection(shape);
+    }
+  }
+
+  // we cannot generate a geometry.
+  return null;
+}
+
+export default { generateAlertGeometry };

api-interop-layer/data/alerts/geometry.test.js

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+import sinon from "sinon";
+import { expect } from "chai";
+import * as mariadb from "mariadb";
+import { generateAlertGeometry } from "./geometry.js";
+
+describe("alert geometries", () => {
+  const sandbox = sinon.createSandbox();
+  const db = {
+    query: sandbox.stub(),
+    end: () => Promise.resolve(),
+  };
+
+  // Do this before everything, so it'll happen before any describe blocks run,
+  // otherwise the connection creation won't be stubbed when the script is first
+  // imported below.
+  before(() => {
+    mariadb.default.createConnection.resolves(db);
+  });
+
+  beforeEach(() => {
+    sandbox.resetBehavior();
+    sandbox.resetHistory();
+  });
+
+  it("returns an alert with a geometry as-is", async () => {
+    const rawAlert = {
+      geometry: "existing geometry",
+    };
+
+    const geometry = await generateAlertGeometry(db, rawAlert);
+    expect(geometry).to.equal("existing geometry");
+  });
+
+  it("autogenerates a geometry from affected zones", async () => {
+    const affectedZones = ["zone 1", "zone 2", "zone 3"];
+    const rawAlert = {
+      geometry: false,
+      properties: {
+        affectedZones,
+      },
+    };
+    const query = `SELECT ST_ASGEOJSON(
+        ST_SIMPLIFY(
+          ST_SRID(
+            ST_COLLECT(shape),
+            0
+          ),
+          0.003
+        )
+      )
+        AS shape
+        FROM weathergov_geo_zones
+        WHERE id IN (?,?,?)`;
+    db.query.withArgs(sinon.match(query), sinon.match.same(affectedZones))
+      .resolves([{ shape: { combined: "zones" } }]);
+
+    const geometry = await generateAlertGeometry(db, rawAlert);
+    expect(geometry).to.eql({ combined: "zones" });
+  });
+
+  it("autogenerates a geometry from same geocodes if no zones are present", async () => {
+    const rawAlert = {
+     geometry: false,
+      properties: {
+        geocode: {
+          // SAME code is FIPS code with a leading zero. The leading
+          // zero gets stripped out, so we need to include it here
+          // so we get what we expect later.
+          "SAME": ["0county 1", "0county 2", "0county 3"],
+        },
+      },
+    };
+    const query = `SELECT ST_ASGEOJSON(
+        ST_SIMPLIFY(
+          ST_SRID(
+            ST_COLLECT(shape),
+            0
+          ),
+          0.003
+        )
+      )
+        AS shape
+        FROM weathergov_geo_counties
+        WHERE countyFips IN ('county 1','county 2','county 3')`;
+    db.query.withArgs(sinon.match(query)).resolves([{ shape: { combined: "county" } }]);
+
+    const geometry = await generateAlertGeometry(db, rawAlert);
+    expect(geometry).to.eql({ combined: "county" });
+  });
+
+  it("returns null geometry if no zones or different geocodes are present", async () => {
+    const rawAlert = {
+      geometry: false,
+      properties: {},
+    };
+
+    const geometry = await generateAlertGeometry(db, rawAlert);
+    expect(geometry).to.be.null;
+  });
+});