From 7fa2e1aa0ccc49efac2933e83eca84a45bc53a62 Mon Sep 17 00:00:00 2001
From: sedum <sedum@oziosi.org>
Date: Fri, 13 Jan 2023 22:28:38 +0100
Subject: [PATCH 1/6] init api rate-limit on geolocation api routes

---
 package.json                         |  1 +
 server/api/controller/geolocation.js | 38 ++++++++++++++++++++++++++++
 server/api/index.js                  |  6 ++---
 yarn.lock                            |  7 +++--
 4 files changed, 47 insertions(+), 5 deletions(-)
 create mode 100644 server/api/controller/geolocation.js

diff --git a/package.json b/package.json
index e2c0d2fc..437e4b93 100644
--- a/package.json
+++ b/package.json
@@ -50,6 +50,7 @@
     "dompurify": "^2.4.1",
     "email-templates": "^10.0.1",
     "express": "^4.18.1",
+    "express-rate-limit": "^6.7.0",
     "http-signature": "^1.3.6",
     "https-proxy-agent": "^5.0.1",
     "ical.js": "^1.5.0",
diff --git a/server/api/controller/geolocation.js b/server/api/controller/geolocation.js
new file mode 100644
index 00000000..fd0aa220
--- /dev/null
+++ b/server/api/controller/geolocation.js
@@ -0,0 +1,38 @@
+const rateLimit = require('express-rate-limit');
+const log = require('../../log')
+let curReq
+
+const geolocationController = {
+  rateLimiter: rateLimit({
+    windowMs: 15 * 60 * 1000, // 15 minutes
+    max: 100, // Limit each IP to 100 requests per `window` (here, per 15 minutes)
+    standardHeaders: true, // Return rate limit info in the `RateLimit-*` headers
+    legacyHeaders: false, // Disable the `X-RateLimit-*` headers
+  }),
+
+  /** 
+   * Limit api usage
+   * From https://operations.osmfoundation.org/policies/nominatim/
+   * [Requirements] No heavy uses (an absolute maximum of 1 request per second).
+   * [Websites and Apps] Note that the usage limits above apply per website/application: the sum of traffic by all your users should not exceed the limits.
+   */
+  apiLimit (req, res, next) {
+    prevReq = curReq
+    curReq = Date.now()
+    deltaTime = (curReq - prevReq)
+
+    if (typeof prevReq === 'undefined' || deltaTime > 1000) {
+      geolocationController.rateLimiter(req, res, next)
+    } else {
+      log.warn('More than 1 request per second to geolocation api come from ' + req.ip)
+
+      setTimeout(() => {
+        geolocationController.rateLimiter(req, res, next)
+      }, 1000 - deltaTime)
+    }
+    
+  }
+  
+}
+
+module.exports = geolocationController
\ No newline at end of file
diff --git a/server/api/index.js b/server/api/index.js
index 49d0e61d..32e15198 100644
--- a/server/api/index.js
+++ b/server/api/index.js
@@ -19,6 +19,7 @@ const resourceController = require('./controller/resource')
 const oauthController = require('./controller/oauth')
 const announceController = require('./controller/announce')
 const pluginController = require('./controller/plugins')
+const geolocationController = require('./controller/geolocation')
 const helpers = require('../helpers')
 const storage = require('./storage')
 
@@ -65,7 +66,6 @@ module.exports = () => {
     api.get('/ping', (_req, res) => res.sendStatus(200))
     api.get('/user', isAuth, (req, res) => res.json(req.user))
   
-  
     api.post('/user/recover', userController.forgotPassword)
     api.post('/user/check_recover_code', userController.checkRecoverCode)
     api.post('/user/recover_password', userController.updatePasswordWithRecoverCode)
@@ -173,8 +173,8 @@ module.exports = () => {
     api.put('/place', isAdmin, placeController.updatePlace)
 
     // - GEOCODING
-    api.get('/placeOSM/Nominatim/:place_details', helpers.isGeocodingEnabled, placeController._nominatim)
-    api.get('/placeOSM/Photon/:place_details', helpers.isGeocodingEnabled, placeController._photon)
+    api.get('/placeOSM/Nominatim/:place_details', helpers.isGeocodingEnabled, geolocationController.apiLimit, placeController._nominatim)
+    api.get('/placeOSM/Photon/:place_details', helpers.isGeocodingEnabled, geolocationController.apiLimit, placeController._photon)
   
     // - TAGS
     api.get('/tags', isAdmin, tagController.getAll)
diff --git a/yarn.lock b/yarn.lock
index 7de9e8e5..2445ccf5 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -5160,6 +5160,11 @@ expect@^29.3.1:
     jest-message-util "^29.3.1"
     jest-util "^29.3.1"
 
+express-rate-limit@^6.7.0:
+  version "6.7.0"
+  resolved "https://registry.yarnpkg.com/express-rate-limit/-/express-rate-limit-6.7.0.tgz#6aa8a1bd63dfe79702267b3af1161a93afc1d3c2"
+  integrity sha512-vhwIdRoqcYB/72TK3tRZI+0ttS8Ytrk24GfmsxDXK9o9IhHNO5bXRiXQSExPQ4GbaE5tvIS7j1SGrxsuWs+sGA==
+
 express@^4.18.1:
   version "4.18.2"
   resolved "https://registry.yarnpkg.com/express/-/express-4.18.2.tgz#3fabe08296e930c796c19e3c516979386ba9fd59"
@@ -12636,10 +12641,8 @@ watchpack@^1.7.4:
   resolved "https://registry.yarnpkg.com/watchpack/-/watchpack-1.7.5.tgz#1267e6c55e0b9b5be44c2023aed5437a2c26c453"
   integrity sha512-9P3MWk6SrKjHsGkLT2KHXdQ/9SNkyoJbabxnKOoJepsvJjJG8uYTR3yTPxPQvNDI3w4Nz1xnE0TLHK4RIVe/MQ==
   dependencies:
-    chokidar "^3.4.1"
     graceful-fs "^4.1.2"
     neo-async "^2.5.0"
-    watchpack-chokidar2 "^2.0.1"
   optionalDependencies:
     chokidar "^3.4.1"
     watchpack-chokidar2 "^2.0.1"

From ebb3fcbd93b4b5290684c8805fc7a1f4a596af7b Mon Sep 17 00:00:00 2001
From: sedum <sedum@oziosi.org>
Date: Sat, 14 Jan 2023 14:53:51 +0100
Subject: [PATCH 2/6] geolocation api rate-limit: add a delay of at least 1s
 between requests

---
 server/api/controller/geolocation.js | 28 ++++++++++++++++++----------
 1 file changed, 18 insertions(+), 10 deletions(-)

diff --git a/server/api/controller/geolocation.js b/server/api/controller/geolocation.js
index fd0aa220..9ff07ead 100644
--- a/server/api/controller/geolocation.js
+++ b/server/api/controller/geolocation.js
@@ -1,6 +1,6 @@
 const rateLimit = require('express-rate-limit');
 const log = require('../../log')
-let curReq
+let d // departure time
 
 const geolocationController = {
   rateLimiter: rateLimit({
@@ -17,18 +17,26 @@ const geolocationController = {
    * [Websites and Apps] Note that the usage limits above apply per website/application: the sum of traffic by all your users should not exceed the limits.
    */
   apiLimit (req, res, next) {
-    prevReq = curReq
-    curReq = Date.now()
-    deltaTime = (curReq - prevReq)
+    let dprev = d // departure time of previous
+    let a = Date.now() // arrival time
 
-    if (typeof prevReq === 'undefined' || deltaTime > 1000) {
-      geolocationController.rateLimiter(req, res, next)
-    } else {
-      log.warn('More than 1 request per second to geolocation api come from ' + req.ip)
+    if (typeof dprev !== 'undefined') {
+      d = dprev + 1000
 
-      setTimeout(() => {
+      if (a > d) {
+        d = a + 10
         geolocationController.rateLimiter(req, res, next)
-      }, 1000 - deltaTime)
+      } else {
+        let wait = d - a
+        log.warn('More than 1 request per second to geolocation api. This from ' + req.ip)
+
+        setTimeout(() => {
+          geolocationController.rateLimiter(req, res, next)
+        }, wait)
+      }
+    } else {
+      d = a + 10 // add 10ms
+      geolocationController.rateLimiter(req, res, next)
     }
     
   }

From 6ee96fb07c1357cdeee4df3d3bfc3b53d221d7a9 Mon Sep 17 00:00:00 2001
From: sedum <sedum@oziosi.org>
Date: Thu, 19 Jan 2023 01:29:24 +0100
Subject: [PATCH 3/6] geolocation api rate-limit: improve the delay mechanism
 to be sure to don't hit provider more than 1 time/s, add memory-cache to save
 response data.

---
 package.json                         |   1 +
 server/api/controller/geolocation.js | 128 ++++++++++++++++++++++-----
 server/api/controller/place.js       |  44 +--------
 server/api/index.js                  |   4 +-
 yarn.lock                            |   5 ++
 5 files changed, 115 insertions(+), 67 deletions(-)

diff --git a/package.json b/package.json
index 437e4b93..7046e50a 100644
--- a/package.json
+++ b/package.json
@@ -62,6 +62,7 @@
     "linkifyjs": "4.0.2",
     "lodash": "^4.17.21",
     "mariadb": "^3.0.1",
+    "memory-cache": "^0.2.0",
     "microformat-node": "^2.0.1",
     "minify-css-string": "^1.0.0",
     "mkdirp": "^1.0.4",
diff --git a/server/api/controller/geolocation.js b/server/api/controller/geolocation.js
index 9ff07ead..0233e919 100644
--- a/server/api/controller/geolocation.js
+++ b/server/api/controller/geolocation.js
@@ -1,9 +1,18 @@
 const rateLimit = require('express-rate-limit');
 const log = require('../../log')
-let d // departure time
+const NOMINATIM_URL = 'https://nominatim.openstreetmap.org/search'
+const PHOTON_URL = 'https://photon.komoot.io/api/'
+const axios = require('axios')
+const { version } = require('../../../package.json')
+const cache = require('memory-cache');
+let d = 0 // departure time
+let h = 0 // hit geocoding provider time (aka Latency)
 
 const geolocationController = {
-  rateLimiter: rateLimit({
+  /**
+   * TODO: replace/merge with a general 'instance rate-limiter' or 'instance api-related rate-limiter' when this will be defined
+   */  
+  instanceApiRateLimiter: rateLimit({
     windowMs: 15 * 60 * 1000, // 15 minutes
     max: 100, // Limit each IP to 100 requests per `window` (here, per 15 minutes)
     standardHeaders: true, // Return rate limit info in the `RateLimit-*` headers
@@ -14,33 +23,108 @@ const geolocationController = {
    * Limit api usage
    * From https://operations.osmfoundation.org/policies/nominatim/
    * [Requirements] No heavy uses (an absolute maximum of 1 request per second).
-   * [Websites and Apps] Note that the usage limits above apply per website/application: the sum of traffic by all your users should not exceed the limits.
+   * [Websites and Apps] 
+   * - Note that the usage limits above apply per website/application: the sum of traffic by all your users should not exceed the limits.
+   * - If at all possible, set up a proxy and also enable caching of requests. 
    */
-  apiLimit (req, res, next) {
-    let dprev = d // departure time of previous
-    let a = Date.now() // arrival time
+  providerRateLimit (req, res, next) {
+    let a = Date.now(); // arrival time
+    let dprev = d
+    d = dprev + 1000 + h
 
-    if (typeof dprev !== 'undefined') {
-      d = dprev + 1000
+    console.log('a: ' + a)
+    console.log('dprev: ' + dprev)
+    console.log('d: ' + d)
 
-      if (a > d) {
-        d = a + 10
-        geolocationController.rateLimiter(req, res, next)
-      } else {
-        let wait = d - a
-        log.warn('More than 1 request per second to geolocation api. This from ' + req.ip)
-
-        setTimeout(() => {
-          geolocationController.rateLimiter(req, res, next)
-        }, wait)
+    // if the same request was already cached skip the delay mechanism
+    if (cache.get(req.params.place_details)) {
+      if (a < d) {
+        log.warn('More than 1 request per second to geolocation api. This from ' + req.ip + ' . The response data is served from memory-cache')
       }
+      // reset departure time because there is no need to ask provider
+      d = dprev
+      return next()
+    }
+
+    if (d === 0 || a > d) {
+      // no-queue or old-queue
+      console.log('No queue or Old queue')
+      // arrival time + 10ms estimated computing time
+      d = a + 10 
+      next()
     } else {
-      d = a + 10 // add 10ms
-      geolocationController.rateLimiter(req, res, next)
+      // fresh queue
+      console.log('Fresh queue')
+      let wait = d - a
+      console.log('Waiting '+ wait)
+      log.warn('More than 1 request per second to geolocation api. This from ' + req.ip + ' . Applying ToS padding before asking to provider. The response data is now cached.')
+      
+      setTimeout(() => {
+        next()
+      }, wait)
     }
     
-  }
-  
+  },
+
+  async _nominatim (req, res) {
+    const details = req.params.place_details
+    const countrycodes = res.locals.settings.geocoding_countrycodes || []
+    const geocoding_provider = res.locals.settings.geocoding_provider || NOMINATIM_URL
+    // ?limit=3&format=json&namedetails=1&addressdetails=1&q=
+
+    const ret = await axios.get(`${geocoding_provider}`, {
+      params: {
+        countrycodes: countrycodes.join(','),
+        q: details,
+        limit: 3,
+        format: 'json',
+        addressdetails: 1,
+        namedetails: 1,
+      },
+      headers: { 'User-Agent': `gancio ${version}` }
+    })
+
+    return res.json(ret.data)
+
+  },
+
+  async _photon (req, res) {
+    const details = req.params.place_details
+    const geocoding_provider = res.locals.settings.geocoding_provider || PHOTON_URL
+
+    if (cache.get(details)) { 
+      console.log('Retrieving data from cache')
+      const ret = {
+        data: await cache.get(details) 
+      }
+      return res.json(ret.data) 
+    } else {
+      let RTTstart = Date.now()
+
+      console.log('Asking Provider: ' + RTTstart)
+      const ret = await axios.get(`${geocoding_provider}`, {
+        params: {
+          q: details,
+          limit: 3,
+        },
+        headers: { 'User-Agent': `gancio ${version}` }
+      })
+
+      if (ret) { 
+        let RTTend = Date.now()
+        console.log('Response arrived: ' + RTTend)
+        // Save the hit time (aka Latency)
+        h = (RTTend - RTTstart) / 2
+        console.log('Saving latency h: ' + h)
+      }
+
+      console.log('Caching results')
+      cache.put(details, ret.data);
+      return res.json(ret.data)
+    }
+ 
+  },
+
 }
 
 module.exports = geolocationController
\ No newline at end of file
diff --git a/server/api/controller/place.js b/server/api/controller/place.js
index 8fd1aa3b..47f71b34 100644
--- a/server/api/controller/place.js
+++ b/server/api/controller/place.js
@@ -7,9 +7,6 @@ const { version } = require('../../../package.json')
 
 const log = require('../../log')
 const { Op, where, col, fn, cast } = require('sequelize')
-const NOMINATIM_URL = 'https://nominatim.openstreetmap.org/search'
-const PHOTON_URL = 'https://photon.komoot.io/api/'
-const axios = require('axios')
 
 module.exports = {
 
@@ -75,45 +72,6 @@ module.exports = {
 
     // TOFIX: don't know why limit does not work
     return res.json(places.slice(0, 10))
-  },
-
-  async _nominatim (req, res) {
-    const details = req.params.place_details
-    const countrycodes = res.locals.settings.geocoding_countrycodes || []
-    const geocoding_provider = res.locals.settings.geocoding_provider || NOMINATIM_URL
-    // ?limit=3&format=json&namedetails=1&addressdetails=1&q=
-
-    const ret = await axios.get(`${geocoding_provider}`, {
-      params: {
-        countrycodes: countrycodes.join(','),
-        q: details,
-        limit: 3,
-        format: 'json',
-        addressdetails: 1,
-        namedetails: 1,
-      },
-      headers: { 'User-Agent': `gancio ${version}` }
-    })
-
-    return res.json(ret.data)
-
-  },
-
-  async _photon (req, res) {
-    const details = req.params.place_details
-    const geocoding_provider = res.locals.settings.geocoding_provider || PHOTON_URL
-
-    const ret = await axios.get(`${geocoding_provider}`, {
-      params: {
-        q: details,
-        limit: 3,
-      },
-      headers: { 'User-Agent': `gancio ${version}` }
-    })
-
-    // console.log(ret)
-    return res.json(ret.data)
-
-  },
+  }
 
 }
diff --git a/server/api/index.js b/server/api/index.js
index 32e15198..a2cecb4f 100644
--- a/server/api/index.js
+++ b/server/api/index.js
@@ -173,8 +173,8 @@ module.exports = () => {
     api.put('/place', isAdmin, placeController.updatePlace)
 
     // - GEOCODING
-    api.get('/placeOSM/Nominatim/:place_details', helpers.isGeocodingEnabled, geolocationController.apiLimit, placeController._nominatim)
-    api.get('/placeOSM/Photon/:place_details', helpers.isGeocodingEnabled, geolocationController.apiLimit, placeController._photon)
+    api.get('/placeOSM/Nominatim/:place_details', helpers.isGeocodingEnabled, geolocationController.instanceApiRateLimiter, geolocationController.providerRateLimit, geolocationController._nominatim)
+    api.get('/placeOSM/Photon/:place_details', helpers.isGeocodingEnabled, geolocationController.instanceApiRateLimiter, geolocationController.providerRateLimit, geolocationController._photon)
   
     // - TAGS
     api.get('/tags', isAdmin, tagController.getAll)
diff --git a/yarn.lock b/yarn.lock
index 2445ccf5..a5d03c8d 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -7950,6 +7950,11 @@ memoizee@^0.4.15:
     next-tick "^1.1.0"
     timers-ext "^0.1.7"
 
+memory-cache@^0.2.0:
+  version "0.2.0"
+  resolved "https://registry.yarnpkg.com/memory-cache/-/memory-cache-0.2.0.tgz#7890b01d52c00c8ebc9d533e1f8eb17e3034871a"
+  integrity sha512-OcjA+jzjOYzKmKS6IQVALHLVz+rNTMPoJvCztFaZxwG14wtAW7VRZjwTQu06vKCYOxh4jVnik7ya0SXTB0W+xA==
+
 memory-fs@^0.4.1:
   version "0.4.1"
   resolved "https://registry.yarnpkg.com/memory-fs/-/memory-fs-0.4.1.tgz#3a9a20b8462523e447cfbc7e8bb80ed667bfc552"

From cc4bb69667ea9ab905532fd5856ac10e7312187e Mon Sep 17 00:00:00 2001
From: sedum <sedum@oziosi.org>
Date: Thu, 19 Jan 2023 12:06:23 +0100
Subject: [PATCH 4/6] geolocation api rate-limit: add per-provider prefix to
 cached response, refactor geocoding provider code

---
 server/api/controller/geocoding.js     | 135 +++++++++++++++++++++++++
 server/api/controller/geolocation.js   | 130 ------------------------
 server/api/index.js                    |   6 +-
 server/services/geocoding/nominatim.js |  23 +++++
 server/services/geocoding/photon.js    |  18 ++++
 5 files changed, 179 insertions(+), 133 deletions(-)
 create mode 100644 server/api/controller/geocoding.js
 delete mode 100644 server/api/controller/geolocation.js
 create mode 100644 server/services/geocoding/nominatim.js
 create mode 100644 server/services/geocoding/photon.js

diff --git a/server/api/controller/geocoding.js b/server/api/controller/geocoding.js
new file mode 100644
index 00000000..5e382640
--- /dev/null
+++ b/server/api/controller/geocoding.js
@@ -0,0 +1,135 @@
+const rateLimit = require('express-rate-limit');
+const log = require('../../log')
+const nominatim = require('../../services/geocoding/nominatim')
+const photon = require('../../services/geocoding/photon')
+const axios = require('axios')
+const { version } = require('../../../package.json')
+const cache = require('memory-cache');
+let d = 0 // departure time
+let h = 0 // hit geocoding provider time (aka Latency)
+
+const geocodingController = {
+  /**
+   * TODO: replace/merge with a general 'instance rate-limiter' or 'instance api-related rate-limiter' when this will be defined
+   */  
+  instanceApiRateLimiter: rateLimit({
+    windowMs: 15 * 60 * 1000, // 15 minutes
+    max: 100, // Limit each IP to 100 requests per `window` (here, per 15 minutes)
+    standardHeaders: true, // Return rate limit info in the `RateLimit-*` headers
+    legacyHeaders: false, // Disable the `X-RateLimit-*` headers
+  }),
+
+  /** 
+   * Limit provider api usage.
+   * From https://operations.osmfoundation.org/policies/nominatim/
+   * [Requirements] No heavy uses (an absolute maximum of 1 request per second).
+   * [Websites and Apps] 
+   * - Note that the usage limits above apply per website/application: the sum of traffic by all your users should not exceed the limits.
+   * - If at all possible, set up a proxy and also enable caching of requests. 
+   */
+  providerRateLimit (req, res, next, providerCommonName) {
+    let a = Date.now(); // arrival time
+    let dprev = d
+    d = dprev + 1000 + h
+
+    console.log('a: ' + a)
+    console.log('dprev: ' + dprev)
+    console.log('d: ' + d)
+
+    // if the same request was already cached skip the delay mechanism
+    if (cache.get(providerCommonName + '_' + req.params.place_details)) {
+      if (a < d) {
+        log.warn('More than 1 request per second to geocoding api. This from ' + req.ip + ' . The response data is served from memory-cache')
+      }
+      console.log('yet cached')
+      // reset departure time because there is no need to ask provider
+      d = dprev
+      return next()
+    }
+
+    if (d === 0 || a > d) {
+      // no-queue or old-queue
+      console.log('No queue or Old queue')
+      // arrival time + 10ms estimated computing time
+      d = a + 10 
+      next()
+    } else {
+      // fresh queue
+      console.log('Fresh queue')
+      let wait = d - a
+      console.log('Waiting '+ wait)
+      log.warn('More than 1 request per second to geocoding api. This from ' + req.ip + ' . Applying ToS padding before asking to provider. The response data is now cached.')
+      
+      setTimeout(() => {
+        next()
+      }, wait)
+    }
+    
+  },
+
+  async nominatimRateLimit(req, res, next) {
+    geocodingController.providerRateLimit(req, res, next, nominatim.commonName)
+  },
+
+  async photonRateLimit(req, res, next) {
+    geocodingController.providerRateLimit(req, res, next, photon.commonName)
+  },
+
+  async checkInCache (req, res, details, providerCommonName) {
+    if (cache.get(providerCommonName + '_' + details)) { 
+      const ret = await cache.get(providerCommonName + '_' + details) 
+      return ret
+    } else {
+      console.log('Not in cache')
+      return
+    }
+  },
+
+  async queryProvider(req, res, details, provider) {
+    let RTTstart = Date.now()
+    console.log('Asking Provider: ' + RTTstart)
+
+    const ret = await axios.get(`${provider.endpoint(req, res)}`, { 
+      params: provider.getParams(req, res),
+      headers: { 'User-Agent': `gancio ${version}` }
+    })
+
+    if (ret) {
+      let RTTend = Date.now()
+      console.log('Asking Provider: ' + RTTend)
+      // Save the hit time (aka Latency)
+      console.log('Saving latency h: ' + h)
+      h = (RTTend - RTTstart) / 2
+    }
+
+    // Cache the response data
+    cache.put(provider.commonName + '_' + details, ret.data, 1000 * 60 * 60 * 24);
+    console.log(cache.keys())
+    console.log(cache.exportJson())
+    return ret.data
+  },
+
+
+  async _nominatim (req, res) {
+    const details = req.params.place_details
+
+    const ret = await geocodingController.checkInCache(req, res, details, nominatim.commonName) ||
+      await geocodingController.queryProvider(req, res, details, nominatim)
+
+    return res.json(ret)
+
+  },
+
+  async _photon (req, res) {
+    const details = req.params.place_details
+
+    const ret = await geocodingController.checkInCache(req, res, details, photon.commonName) ||
+      await geocodingController.queryProvider(req, res, details, photon)
+
+    return res.json(ret)
+
+  },
+
+}
+
+module.exports = geocodingController
\ No newline at end of file
diff --git a/server/api/controller/geolocation.js b/server/api/controller/geolocation.js
deleted file mode 100644
index 0233e919..00000000
--- a/server/api/controller/geolocation.js
+++ /dev/null
@@ -1,130 +0,0 @@
-const rateLimit = require('express-rate-limit');
-const log = require('../../log')
-const NOMINATIM_URL = 'https://nominatim.openstreetmap.org/search'
-const PHOTON_URL = 'https://photon.komoot.io/api/'
-const axios = require('axios')
-const { version } = require('../../../package.json')
-const cache = require('memory-cache');
-let d = 0 // departure time
-let h = 0 // hit geocoding provider time (aka Latency)
-
-const geolocationController = {
-  /**
-   * TODO: replace/merge with a general 'instance rate-limiter' or 'instance api-related rate-limiter' when this will be defined
-   */  
-  instanceApiRateLimiter: rateLimit({
-    windowMs: 15 * 60 * 1000, // 15 minutes
-    max: 100, // Limit each IP to 100 requests per `window` (here, per 15 minutes)
-    standardHeaders: true, // Return rate limit info in the `RateLimit-*` headers
-    legacyHeaders: false, // Disable the `X-RateLimit-*` headers
-  }),
-
-  /** 
-   * Limit api usage
-   * From https://operations.osmfoundation.org/policies/nominatim/
-   * [Requirements] No heavy uses (an absolute maximum of 1 request per second).
-   * [Websites and Apps] 
-   * - Note that the usage limits above apply per website/application: the sum of traffic by all your users should not exceed the limits.
-   * - If at all possible, set up a proxy and also enable caching of requests. 
-   */
-  providerRateLimit (req, res, next) {
-    let a = Date.now(); // arrival time
-    let dprev = d
-    d = dprev + 1000 + h
-
-    console.log('a: ' + a)
-    console.log('dprev: ' + dprev)
-    console.log('d: ' + d)
-
-    // if the same request was already cached skip the delay mechanism
-    if (cache.get(req.params.place_details)) {
-      if (a < d) {
-        log.warn('More than 1 request per second to geolocation api. This from ' + req.ip + ' . The response data is served from memory-cache')
-      }
-      // reset departure time because there is no need to ask provider
-      d = dprev
-      return next()
-    }
-
-    if (d === 0 || a > d) {
-      // no-queue or old-queue
-      console.log('No queue or Old queue')
-      // arrival time + 10ms estimated computing time
-      d = a + 10 
-      next()
-    } else {
-      // fresh queue
-      console.log('Fresh queue')
-      let wait = d - a
-      console.log('Waiting '+ wait)
-      log.warn('More than 1 request per second to geolocation api. This from ' + req.ip + ' . Applying ToS padding before asking to provider. The response data is now cached.')
-      
-      setTimeout(() => {
-        next()
-      }, wait)
-    }
-    
-  },
-
-  async _nominatim (req, res) {
-    const details = req.params.place_details
-    const countrycodes = res.locals.settings.geocoding_countrycodes || []
-    const geocoding_provider = res.locals.settings.geocoding_provider || NOMINATIM_URL
-    // ?limit=3&format=json&namedetails=1&addressdetails=1&q=
-
-    const ret = await axios.get(`${geocoding_provider}`, {
-      params: {
-        countrycodes: countrycodes.join(','),
-        q: details,
-        limit: 3,
-        format: 'json',
-        addressdetails: 1,
-        namedetails: 1,
-      },
-      headers: { 'User-Agent': `gancio ${version}` }
-    })
-
-    return res.json(ret.data)
-
-  },
-
-  async _photon (req, res) {
-    const details = req.params.place_details
-    const geocoding_provider = res.locals.settings.geocoding_provider || PHOTON_URL
-
-    if (cache.get(details)) { 
-      console.log('Retrieving data from cache')
-      const ret = {
-        data: await cache.get(details) 
-      }
-      return res.json(ret.data) 
-    } else {
-      let RTTstart = Date.now()
-
-      console.log('Asking Provider: ' + RTTstart)
-      const ret = await axios.get(`${geocoding_provider}`, {
-        params: {
-          q: details,
-          limit: 3,
-        },
-        headers: { 'User-Agent': `gancio ${version}` }
-      })
-
-      if (ret) { 
-        let RTTend = Date.now()
-        console.log('Response arrived: ' + RTTend)
-        // Save the hit time (aka Latency)
-        h = (RTTend - RTTstart) / 2
-        console.log('Saving latency h: ' + h)
-      }
-
-      console.log('Caching results')
-      cache.put(details, ret.data);
-      return res.json(ret.data)
-    }
- 
-  },
-
-}
-
-module.exports = geolocationController
\ No newline at end of file
diff --git a/server/api/index.js b/server/api/index.js
index a2cecb4f..1dfae154 100644
--- a/server/api/index.js
+++ b/server/api/index.js
@@ -19,7 +19,7 @@ const resourceController = require('./controller/resource')
 const oauthController = require('./controller/oauth')
 const announceController = require('./controller/announce')
 const pluginController = require('./controller/plugins')
-const geolocationController = require('./controller/geolocation')
+const geocodingController = require('./controller/geocoding')
 const helpers = require('../helpers')
 const storage = require('./storage')
 
@@ -173,8 +173,8 @@ module.exports = () => {
     api.put('/place', isAdmin, placeController.updatePlace)
 
     // - GEOCODING
-    api.get('/placeOSM/Nominatim/:place_details', helpers.isGeocodingEnabled, geolocationController.instanceApiRateLimiter, geolocationController.providerRateLimit, geolocationController._nominatim)
-    api.get('/placeOSM/Photon/:place_details', helpers.isGeocodingEnabled, geolocationController.instanceApiRateLimiter, geolocationController.providerRateLimit, geolocationController._photon)
+    api.get('/placeOSM/Nominatim/:place_details', helpers.isGeocodingEnabled, geocodingController.instanceApiRateLimiter, geocodingController.nominatimRateLimit, geocodingController._nominatim)
+    api.get('/placeOSM/Photon/:place_details', helpers.isGeocodingEnabled, geocodingController.instanceApiRateLimiter, geocodingController.photonRateLimit, geocodingController._photon)
   
     // - TAGS
     api.get('/tags', isAdmin, tagController.getAll)
diff --git a/server/services/geocoding/nominatim.js b/server/services/geocoding/nominatim.js
new file mode 100644
index 00000000..8b55153a
--- /dev/null
+++ b/server/services/geocoding/nominatim.js
@@ -0,0 +1,23 @@
+
+module.exports = {
+  commonName: 'Nominatim',
+  DEFAULT_ENDPOINT: 'https://nominatim.openstreetmap.org/search',
+  endpoint: (req, res) => { 
+    return res.locals.settings.geocoding_provider || this.DEFAULT_ENDPOINT
+  },
+
+  getParams (req, res) {
+    const countrycodes = res.locals.settings.geocoding_countrycodes || []
+    const details = req.params.place_details
+
+    return {
+      countrycodes: countrycodes.join(','),
+      q: details,
+      limit: 3,
+      format: 'json',
+      addressdetails: 1,
+      namedetails: 1,
+    }
+  },
+
+}
\ No newline at end of file
diff --git a/server/services/geocoding/photon.js b/server/services/geocoding/photon.js
new file mode 100644
index 00000000..29a4dfda
--- /dev/null
+++ b/server/services/geocoding/photon.js
@@ -0,0 +1,18 @@
+
+module.exports = {
+  commonName: 'Photon',
+  DEFAULT_ENDPOINT: 'https://photon.komoot.io/api/',
+  endpoint: (req, res) => {
+    return res.locals.settings.geocoding_provider || this.DEFAULT_ENDPOINT
+  },
+
+  getParams (req, res) {
+    const details = req.params.place_details
+
+    return {
+      q: details,
+      limit: 3,
+    }
+  }
+
+}
\ No newline at end of file

From c50d369de9132b14da75a4a6312a5b9493c8cb7d Mon Sep 17 00:00:00 2001
From: sedum <sedum@oziosi.org>
Date: Thu, 19 Jan 2023 12:20:52 +0100
Subject: [PATCH 5/6] geolocation api rate-limit: commented debug messages

---
 server/api/controller/geocoding.js | 27 +++++++++++++--------------
 1 file changed, 13 insertions(+), 14 deletions(-)

diff --git a/server/api/controller/geocoding.js b/server/api/controller/geocoding.js
index 5e382640..c7b9fd9a 100644
--- a/server/api/controller/geocoding.js
+++ b/server/api/controller/geocoding.js
@@ -32,16 +32,15 @@ const geocodingController = {
     let dprev = d
     d = dprev + 1000 + h
 
-    console.log('a: ' + a)
-    console.log('dprev: ' + dprev)
-    console.log('d: ' + d)
+    // console.log('a: ' + a)
+    // console.log('dprev: ' + dprev)
+    // console.log('d: ' + d)
 
     // if the same request was already cached skip the delay mechanism
     if (cache.get(providerCommonName + '_' + req.params.place_details)) {
       if (a < d) {
-        log.warn('More than 1 request per second to geocoding api. This from ' + req.ip + ' . The response data is served from memory-cache')
+        log.warn('More than 1 request per second to geocoding api. This from ' + req.ip + ' . The response data is served from memory-cache.')
       }
-      console.log('yet cached')
       // reset departure time because there is no need to ask provider
       d = dprev
       return next()
@@ -49,15 +48,15 @@ const geocodingController = {
 
     if (d === 0 || a > d) {
       // no-queue or old-queue
-      console.log('No queue or Old queue')
+      // console.log('No queue or Old queue')
       // arrival time + 10ms estimated computing time
       d = a + 10 
       next()
     } else {
       // fresh queue
-      console.log('Fresh queue')
+      // console.log('Fresh queue')
       let wait = d - a
-      console.log('Waiting '+ wait)
+      // console.log('Waiting '+ wait)
       log.warn('More than 1 request per second to geocoding api. This from ' + req.ip + ' . Applying ToS padding before asking to provider. The response data is now cached.')
       
       setTimeout(() => {
@@ -80,14 +79,14 @@ const geocodingController = {
       const ret = await cache.get(providerCommonName + '_' + details) 
       return ret
     } else {
-      console.log('Not in cache')
+      // console.log('Not in cache')
       return
     }
   },
 
   async queryProvider(req, res, details, provider) {
     let RTTstart = Date.now()
-    console.log('Asking Provider: ' + RTTstart)
+    // console.log('Asking Provider: ' + RTTstart)
 
     const ret = await axios.get(`${provider.endpoint(req, res)}`, { 
       params: provider.getParams(req, res),
@@ -96,16 +95,16 @@ const geocodingController = {
 
     if (ret) {
       let RTTend = Date.now()
-      console.log('Asking Provider: ' + RTTend)
+      // console.log('Asking Provider: ' + RTTend)
       // Save the hit time (aka Latency)
-      console.log('Saving latency h: ' + h)
+      // console.log('Saving latency h: ' + h)
       h = (RTTend - RTTstart) / 2
     }
 
     // Cache the response data
     cache.put(provider.commonName + '_' + details, ret.data, 1000 * 60 * 60 * 24);
-    console.log(cache.keys())
-    console.log(cache.exportJson())
+    // console.log(cache.keys())
+    // console.log(cache.exportJson())
     return ret.data
   },
 

From ad3ace1e7e77a3c867b00a9c7363c11d1c651a83 Mon Sep 17 00:00:00 2001
From: sedum <sedum@oziosi.org>
Date: Sat, 21 Jan 2023 01:18:16 +0100
Subject: [PATCH 6/6] geolocation api rate-limit: split cache instance, one for
 each provider

---
 server/api/controller/geocoding.js     | 22 ++++++++++------------
 server/services/geocoding/nominatim.js | 11 ++++++++---
 server/services/geocoding/photon.js    | 11 ++++++++---
 3 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/server/api/controller/geocoding.js b/server/api/controller/geocoding.js
index c7b9fd9a..a86b1ca3 100644
--- a/server/api/controller/geocoding.js
+++ b/server/api/controller/geocoding.js
@@ -4,7 +4,6 @@ const nominatim = require('../../services/geocoding/nominatim')
 const photon = require('../../services/geocoding/photon')
 const axios = require('axios')
 const { version } = require('../../../package.json')
-const cache = require('memory-cache');
 let d = 0 // departure time
 let h = 0 // hit geocoding provider time (aka Latency)
 
@@ -27,7 +26,7 @@ const geocodingController = {
    * - Note that the usage limits above apply per website/application: the sum of traffic by all your users should not exceed the limits.
    * - If at all possible, set up a proxy and also enable caching of requests. 
    */
-  providerRateLimit (req, res, next, providerCommonName) {
+  providerRateLimit (req, res, next, providerCache) {
     let a = Date.now(); // arrival time
     let dprev = d
     d = dprev + 1000 + h
@@ -37,7 +36,7 @@ const geocodingController = {
     // console.log('d: ' + d)
 
     // if the same request was already cached skip the delay mechanism
-    if (cache.get(providerCommonName + '_' + req.params.place_details)) {
+    if (providerCache.get(req.params.place_details)) {
       if (a < d) {
         log.warn('More than 1 request per second to geocoding api. This from ' + req.ip + ' . The response data is served from memory-cache.')
       }
@@ -67,19 +66,18 @@ const geocodingController = {
   },
 
   async nominatimRateLimit(req, res, next) {
-    geocodingController.providerRateLimit(req, res, next, nominatim.commonName)
+    geocodingController.providerRateLimit(req, res, next, nominatim.cache)
   },
 
   async photonRateLimit(req, res, next) {
-    geocodingController.providerRateLimit(req, res, next, photon.commonName)
+    geocodingController.providerRateLimit(req, res, next, photon.cache)
   },
 
-  async checkInCache (req, res, details, providerCommonName) {
-    if (cache.get(providerCommonName + '_' + details)) { 
-      const ret = await cache.get(providerCommonName + '_' + details) 
+  async checkInCache (req, res, details, providerCache) {
+    const ret = await providerCache.get(details)
+    if (ret) {
       return ret
     } else {
-      // console.log('Not in cache')
       return
     }
   },
@@ -102,7 +100,7 @@ const geocodingController = {
     }
 
     // Cache the response data
-    cache.put(provider.commonName + '_' + details, ret.data, 1000 * 60 * 60 * 24);
+    provider.cache.put(details, ret.data, 1000 * 60 * 60 * 24);
     // console.log(cache.keys())
     // console.log(cache.exportJson())
     return ret.data
@@ -112,7 +110,7 @@ const geocodingController = {
   async _nominatim (req, res) {
     const details = req.params.place_details
 
-    const ret = await geocodingController.checkInCache(req, res, details, nominatim.commonName) ||
+    const ret = await geocodingController.checkInCache(req, res, details, nominatim.cache) ||
       await geocodingController.queryProvider(req, res, details, nominatim)
 
     return res.json(ret)
@@ -122,7 +120,7 @@ const geocodingController = {
   async _photon (req, res) {
     const details = req.params.place_details
 
-    const ret = await geocodingController.checkInCache(req, res, details, photon.commonName) ||
+    const ret = await geocodingController.checkInCache(req, res, details, photon.cache) ||
       await geocodingController.queryProvider(req, res, details, photon)
 
     return res.json(ret)
diff --git a/server/services/geocoding/nominatim.js b/server/services/geocoding/nominatim.js
index 8b55153a..9e8b09fd 100644
--- a/server/services/geocoding/nominatim.js
+++ b/server/services/geocoding/nominatim.js
@@ -1,10 +1,13 @@
+const cache = require('memory-cache')
+const providerCache = new cache.Cache()
 
-module.exports = {
+const nominatim = {
   commonName: 'Nominatim',
   DEFAULT_ENDPOINT: 'https://nominatim.openstreetmap.org/search',
   endpoint: (req, res) => { 
-    return res.locals.settings.geocoding_provider || this.DEFAULT_ENDPOINT
+    return res.locals.settings.geocoding_provider || nominatim.DEFAULT_ENDPOINT
   },
+  cache: providerCache,
 
   getParams (req, res) {
     const countrycodes = res.locals.settings.geocoding_countrycodes || []
@@ -20,4 +23,6 @@ module.exports = {
     }
   },
 
-}
\ No newline at end of file
+}
+
+module.exports = nominatim
\ No newline at end of file
diff --git a/server/services/geocoding/photon.js b/server/services/geocoding/photon.js
index 29a4dfda..4eced7db 100644
--- a/server/services/geocoding/photon.js
+++ b/server/services/geocoding/photon.js
@@ -1,10 +1,13 @@
+const cache = require('memory-cache')
+const providerCache = new cache.Cache()
 
-module.exports = {
+const photon = {
   commonName: 'Photon',
   DEFAULT_ENDPOINT: 'https://photon.komoot.io/api/',
   endpoint: (req, res) => {
-    return res.locals.settings.geocoding_provider || this.DEFAULT_ENDPOINT
+    return res.locals.settings.geocoding_provider || photon.DEFAULT_ENDPOINT
   },
+  cache: providerCache,
 
   getParams (req, res) {
     const details = req.params.place_details
@@ -15,4 +18,6 @@ module.exports = {
     }
   }
 
-}
\ No newline at end of file
+}
+
+module.exports = photon
\ No newline at end of file