From ee10c90a4f3aaf99c84ad532b4737748d6481d34 Mon Sep 17 00:00:00 2001
From: jspeis <jspeis@gmail.com>
Date: Thu, 8 Mar 2018 13:50:24 -0500
Subject: [PATCH] adds dynamic column name selection and groups results by
 geographic level

---
 src/api/index.js | 52 ++++++++++++++++++++++++++++++++++--------------
 1 file changed, 37 insertions(+), 15 deletions(-)

diff --git a/src/api/index.js b/src/api/index.js
index 5fd372b..2c9703a 100755
--- a/src/api/index.js
+++ b/src/api/index.js
@@ -1,9 +1,11 @@
 import {Router} from "express";
 
-import levels from "config/levels.json";
 import {version} from "package";
 import dbgeo from "dbgeo";
 
+const levels = require("config/acs_levels.json");
+
+
 function topofy(data, httpResult) {
   const precision = 5;
   const quantization = 100000;
@@ -23,13 +25,30 @@ const levelLookup = geoId => {
     "140": "tract",
     "050": "county",
     "040": "state",
+    "310": "msa",
     "160": "place",
     "860": "zip",
+    "795": "puma",
     "970": "school-district"
   };
   return levelMap[prefix];
 };
 
+
+const groupByLevel = dataArr => {
+  const result = {};
+  dataArr.forEach(row => {
+    const geoId = row.geoid;
+    const myPrefix = geoId.slice(0, 3);
+    const lvl = levelLookup(myPrefix);
+    if (!Object.keys(result).includes(lvl)) {
+      result[lvl] = [];
+    }
+    result[lvl].push(row);
+  });
+  return result;
+}
+
 export default ({db}) => {
   const api = new Router();
 
@@ -48,8 +67,8 @@ export default ({db}) => {
     }
 
     const targetTable = `${levels[level].schema}.${levels[level].table}`;
-
-    const qry = `SELECT * from ${targetTable} s1,
+    const cols = levels[level].columns.map(x => `s2."${x}"`).join(",") || "*";
+    const qry = `SELECT ${cols} from ${targetTable} s1,
               ${targetTable} s2
               WHERE ST_Touches(s1.geom, s2.geom)
               AND s1.geoid = $1;`;
@@ -131,29 +150,32 @@ export default ({db}) => {
     });
   });
 
-  api.get("/related", (req, httpResult) => {
-    const geoId = req.query.target;
-    // const gisCmd = req.params.op === "within" ? "ST_Within" : "ST_Intersects";
+  api.get("/related/:geoId", (req, httpResult) => {
+    const geoId = req.params.geoId || req.query.target;
     const level1 = levelLookup(geoId);
     const includeGeom = req.query.includeGeom ? ", s2.geom" : "";
-
     const targetTable1 = `${levels[level1].schema}.${levels[level1].table}`;
     const targetId1 = levels[level1].id;
+
     const queries = [];
 
     Object.keys(levels).forEach(level => {
-      const targetTable2 = `${levels[level].schema}.${levels[level].table}`;
-
-      const qry = `SELECT s2.geoid, s2.name ${includeGeom} from ${targetTable1} s1,
-                ${targetTable2} s2
-                WHERE (ST_Area(st_intersection(s2.geom, s1.geom)) / st_area(s1.geom)) > 0.001
-                AND s1.${targetId1} = $1`;
-      queries.push(qry);
+      if (level !== level1) {
+        const targetTable2 = `${levels[level].schema}.${levels[level].table}`;
+        const nameColumn2 = levels[level].nameColumn || "name";
+        const gidColumn2 = levels[level].geoColumn || "geoid";
+        const qry = `SELECT s2."${gidColumn2}", s2."${nameColumn2}" as name ${includeGeom} from ${targetTable1} s1,
+                  ${targetTable2} s2
+                  WHERE ST_Intersects(s2.geom, s1.geom)
+                  AND s1.${targetId1} = $1`;
+        queries.push(qry);
+      }
     });
 
     Promise.all(queries.map(q => db.query(q, geoId)))
       .then(values => values.reduce((acc, x) => [...acc, ...x], []))
-      .then(results => topofy(results, httpResult))
+      .then(groupByLevel)
+      .then(results => httpResult.json(results))
       .catch(error => {
         console.error("An error occured", error);
         httpResult.json({error});