{ "id": "OcAQrF91wzWH3rOw", "name": "Generate and Decode DIGIPIN", "tags": [], "nodes": [ { "id": "882aa556-8ea2-4582-8230-7b0e13ad2fd1", "name": "Respond to Webhook - Success", "type": "n8n-nodes-base.respondToWebhook", "position": [ 340, -140 ], "parameters": { "options": { "responseCode": 200 }, "respondWith": "json", "responseBody": "={\n \"status\": \"Success\",\n \"lat\": \"{{ $json.query.lat }}\",\n \"lon\": \"{{ $json.query.lon }}\",\n \"digipin\": \"{{ $json.digipin }}\"\n} " }, "typeVersion": 1.4 }, { "id": "368240b0-cecf-46e7-9509-bfcb1afe7610", "name": "Respond to Webhook - Error", "type": "n8n-nodes-base.respondToWebhook", "position": [ 340, 60 ], "parameters": { "options": { "responseCode": 422 }, "respondWith": "json", "responseBody": "={\n \"status\": \"Failed\",\n \"lat\": \"{{ $json.query.lat }}\",\n \"lon\": \"{{ $json.query.lon }}\",\n \"error\": \"{{ $json.error }}\"\n} " }, "typeVersion": 1.4 }, { "id": "b6c70cd6-3d5f-4215-989c-8a5e6a896564", "name": "Switch - Check for Success", "type": "n8n-nodes-base.switch", "position": [ 120, -40 ], "parameters": { "rules": { "values": [ { "outputKey": "digipin", "conditions": { "options": { "version": 2, "leftValue": "", "caseSensitive": true, "typeValidation": "strict" }, "combinator": "and", "conditions": [ { "id": "3656e246-523a-4611-b563-8e66ae078d67", "operator": { "type": "string", "operation": "exists", "singleValue": true }, "leftValue": "={{ $json.digipin }}", "rightValue": "" } ] }, "renameOutput": true }, { "conditions": { "options": { "version": 2, "leftValue": "", "caseSensitive": true, "typeValidation": "strict" }, "combinator": "and", "conditions": [ { "id": "9b5ef11d-7833-41c3-8611-56cf11df2dcc", "operator": { "type": "string", "operation": "exists", "singleValue": true }, "leftValue": "={{ $json.error }}", "rightValue": "" } ] } } ] }, "options": {} }, "typeVersion": 3.2 }, { "id": "3a7dc7a2-9d19-467c-b651-143187d852d9", "name": "DIGIPIN_Generation_Code", "type": "n8n-nodes-base.code", "position": [ -100, -40 ], "parameters": { "jsCode": "// --- DIGIPIN Generation Logic ---\n\n// Constants for DIGIPIN generation\nconst DIGIPIN_GRID = [\n ['F', 'C', '9', '8'],\n ['J', '3', '2', '7'],\n ['K', '4', '5', '6'],\n ['L', 'M', 'P', 'T']\n];\n\nconst BOUNDS = {\n minLat: 2.5,\n maxLat: 38.5,\n minLon: 63.5,\n maxLon: 99.5\n};\n\n/**\n * Encodes latitude and longitude into a DIGIPIN.\n * @param {number} lat The latitude.\n * @param {number} lon The longitude.\n * @returns {string} The generated DIGIPIN.\n * @throws {Error} If coordinates are out of bounds.\n */\nfunction generateDigiPin(lat, lon) {\n if (lat < BOUNDS.minLat || lat > BOUNDS.maxLat || lon < BOUNDS.minLon || lon > BOUNDS.maxLon) {\n throw new Error(`Coordinates (Lat: ${lat}, Lon: ${lon}) are out of the valid range.`);\n }\n\n let minLat = BOUNDS.minLat, maxLat = BOUNDS.maxLat;\n let minLon = BOUNDS.minLon, maxLon = BOUNDS.maxLon;\n let digiPin = '';\n\n for (let level = 1; level <= 10; level++) {\n const latDiv = (maxLat - minLat) / 4;\n const lonDiv = (maxLon - minLon) / 4;\n let row = 3 - Math.floor((lat - minLat) / latDiv);\n let col = Math.floor((lon - minLon) / lonDiv);\n row = Math.max(0, Math.min(row, 3));\n col = Math.max(0, Math.min(col, 3));\n digiPin += DIGIPIN_GRID[row][col];\n if (level === 3 || level === 6) {\n digiPin += '-';\n }\n maxLat = minLat + latDiv * (4 - row);\n minLat = minLat + latDiv * (3 - row);\n minLon = minLon + lonDiv * col;\n maxLon = minLon + lonDiv;\n }\n return digiPin;\n}\n\n\n// --- n8n Item Processing ---\n// Loop through each input item provided to the node.\nfor (const item of items) {\n try {\n // Get latitude and longitude from the input item's JSON data.\n // Assumes the previous node provides these fields.\n const lat = $input.first().json.query.lat;\n const lon = $input.first().json.query.lon;\n\n if (lat === undefined || lon === undefined) {\n throw new Error(\"Input item is missing 'latitude' or 'longitude' field.\");\n }\n\n // Generate the DIGIPIN.\n const digipinResult = generateDigiPin(lat, lon);\n\n // Add the result to a new field called 'digipin' in the item's JSON.\n item.json.digipin = digipinResult;\n\n } catch (error) {\n // If an error occurs, add an 'error' field to the item.\n // This helps with debugging in the n8n UI.\n item.json.error = error.message;\n }\n}\n\n// Return all the modified items to the next node in the workflow.\nreturn items;\n" }, "typeVersion": 2 }, { "id": "33aab4da-4b77-44fa-85c4-0ed165b416d3", "name": "DIGIPIN_Decode_Code", "type": "n8n-nodes-base.code", "position": [ -100, 420 ], "parameters": { "jsCode": "/**\n * Decodes a DIGIPIN into latitude and longitude coordinates.\n * @param {string} digiPin The DIGIPIN to decode.\n * @returns {{latitude: string, longitude: string}} An object containing the latitude and longitude,\n * each formatted to 6 decimal places.\n * @throws {Error} If the DIGIPIN is invalid or contains invalid characters.\n */\nconst DIGIPIN_GRID = [\n ['F', 'C', '9', '8'],\n ['J', '3', '2', '7'],\n ['K', '4', '5', '6'],\n ['L', 'M', 'P', 'T']\n];\n\n\nconst BOUNDS = {\n minLat: 2.5,\n maxLat: 38.5,\n minLon: 63.5,\n maxLon: 99.5\n};\nfunction getLatLngFromDigiPin(digiPin) {\n const pin = digiPin.replace(/-/g, ''); // Remove hyphens for processing\n if (pin.length !== 10) throw new Error('Invalid DIGIPIN: Must be 10 characters long after removing hyphens.');\n\n let minLat = BOUNDS.minLat;\n let maxLat = BOUNDS.maxLat;\n let minLon = BOUNDS.minLon;\n let maxLon = BOUNDS.minLon; // Corrected initial value here, should be BOUNDS.minLon\n\n // Recalculate maxLon for accurate initial bounds\n // Based on the original DIGIPIN generation, it should cover the whole range initially.\n maxLon = BOUNDS.maxLon;\n\n\n for (let i = 0; i < 10; i++) {\n const char = pin[i];\n let found = false;\n let ri = -1, ci = -1;\n\n for (let r = 0; r < 4; r++) {\n for (let c = 0; c < 4; c++) {\n if (DIGIPIN_GRID[r][c] === char) {\n ri = r;\n ci = c;\n found = true;\n break;\n }\n }\n if (found) break;\n }\n\n if (!found) throw new Error(`Invalid character '${char}' in DIGIPIN.`);\n\n const latDiv = (maxLat - minLat) / 4;\n const lonDiv = (maxLon - minLon) / 4;\n\n const lat1 = maxLat - latDiv * (ri + 1);\n const lat2 = maxLat - latDiv * ri;\n const lon1 = minLon + lonDiv * ci;\n const lon2 = minLon + lonDiv * (ci + 1);\n\n minLat = lat1;\n maxLat = lat2;\n minLon = lon1;\n maxLon = lon2;\n }\n\n const centerLat = (minLat + maxLat) / 2;\n const centerLon = (minLon + maxLon) / 2;\n\n return {\n latitude: centerLat.toFixed(6),\n longitude: centerLon.toFixed(6)\n };\n}\n\n\nconst MY_DIGIPIN = $input.first().json.query.digipin; // <--- REPLACE THIS with your desired DIGIPIN\n\n// Ensure there's at least one item to process, or create a dummy one\nlet outputItems = [];\nif (items.length === 0) {\n // If no items come into the node, create a blank one to attach results to\n outputItems.push({ json: {} });\n} else {\n // If items exist, clone them to add results\n outputItems = JSON.parse(JSON.stringify(items));\n}\n\nfor (const item of outputItems) {\n try {\n const digipinToProcess = MY_DIGIPIN;\n\n if (!digipinToProcess) {\n throw new Error(\"No DIGIPIN specified for processing.\");\n }\n\n // Decode the DIGIPIN\n const decodedCoords = getLatLngFromDigiPin(digipinToProcess);\n\n // Add the result to new fields in the item's JSON\n item.json.processedDigipin = digipinToProcess; // Optional: To see which digipin was processed\n item.json.decodedLatitude = decodedCoords.latitude;\n item.json.decodedLongitude = decodedCoords.longitude;\n\n } catch (error) {\n // If an error occurs, add an 'error' field to the item.\n item.json.error = error.message;\n }\n}\n\n// Return all the modified items to the next node in the workflow.\nreturn outputItems;" }, "typeVersion": 2 }, { "id": "6da5b090-caf7-4a8b-a254-a90ac9b97610", "name": "Encode_Webhook", "type": "n8n-nodes-base.webhook", "position": [ -320, -40 ], "parameters": { "path": "generate-digipin", "options": {}, "responseMode": "responseNode" }, "typeVersion": 2 }, { "id": "99a30d16-696a-4c2c-941d-7b66a6591d54", "name": "Decode_Webhook", "type": "n8n-nodes-base.webhook", "position": [ -320, 420 ], "parameters": { "path": "decode-digipin", "options": {}, "responseMode": "responseNode" }, "typeVersion": 2 }, { "id": "ab871baf-aae7-4060-83af-7794974dce18", "name": "Switch 2 - Check for Success1", "type": "n8n-nodes-base.switch", "position": [ 120, 420 ], "parameters": { "rules": { "values": [ { "outputKey": "coordinates", "conditions": { "options": { "version": 2, "leftValue": "", "caseSensitive": true, "typeValidation": "strict" }, "combinator": "and", "conditions": [ { "id": "3656e246-523a-4611-b563-8e66ae078d67", "operator": { "type": "string", "operation": "exists", "singleValue": true }, "leftValue": "={{ $json.decodedLatitude }}", "rightValue": "" } ] }, "renameOutput": true }, { "conditions": { "options": { "version": 2, "leftValue": "", "caseSensitive": true, "typeValidation": "strict" }, "combinator": "and", "conditions": [ { "id": "9b5ef11d-7833-41c3-8611-56cf11df2dcc", "operator": { "type": "string", "operation": "exists", "singleValue": true }, "leftValue": "={{ $json.error }}", "rightValue": "" } ] } } ] }, "options": {} }, "typeVersion": 3.2 }, { "id": "64409e6c-e4aa-41b2-abcf-a016e729ea37", "name": "Respond to Webhook - Success 2", "type": "n8n-nodes-base.respondToWebhook", "position": [ 340, 320 ], "parameters": { "options": { "responseCode": 200 }, "respondWith": "json", "responseBody": "={\n \"status\": \"Success\",\n \"digipin\": \"{{ $json.query.digipin }}\",\n \"lat\": \"{{ $json.decodedLatitude }}\",\n \"lon\": \"{{ $json.decodedLongitude }}\"\n} " }, "typeVersion": 1.4 }, { "id": "d37184ce-7060-4d06-b039-dd8572e7d3e8", "name": "Respond to Webhook - Error 2", "type": "n8n-nodes-base.respondToWebhook", "position": [ 340, 520 ], "parameters": { "options": { "responseCode": 422 }, "respondWith": "json", "responseBody": "={\n \"status\": \"Failed\",\n \"digipin\": \"{{ $json.query.digipin }}\",\n \"error\": \"{{ $json.error }}\"\n} " }, "typeVersion": 1.4 }, { "id": "8d745b4f-f993-4865-a96f-e3f1e28a0cc2", "name": "Sticky Note", "type": "n8n-nodes-base.stickyNote", "position": [ 660, 360 ], "parameters": { "color": 4, "width": 920, "height": 320, "content": "## Example usage \n\nGenerate a DIGIPIN:\n```\ncurl --request GET \\\n --url 'https://n8n.example.in/webhook/generate-digipin?lat=27.175063&lon=78.042169'\n```\n\nDecode a DIGIPIN:\n```\ncurl --request GET \\\n --url 'https://n8n.example.in/webhook/decode-digipin?digipin=32C-849-5CJ6'\n```" }, "typeVersion": 1 }, { "id": "3cb47a09-ce41-4d2d-a413-885510ebda96", "name": "Sticky Note1", "type": "n8n-nodes-base.stickyNote", "position": [ 660, -160 ], "parameters": { "width": 920, "height": 440, "content": "## DIGIPIN Generator and Decoder\n\nThis n8n workflow lets you **generate and decode DIGIPINs** using only JavaScript - no external APIs involved.\n\nDIGIPIN is India Post\u2019s geolocation code system that encodes latitude and longitude into a 10-character alphanumeric string, like `32C-849-5CJ6`. It helps simplify precise location sharing across India.\n\n### \ud83d\udd27 What it does\n- `/generate-digipin?lat=...&lon=...` \u2192 returns the DIGIPIN for given coordinates\n- `/decode-digipin?digipin=...` \u2192 returns the coordinates for a given DIGIPIN\n\nUseful for: check-in systems, last-mile delivery, digital address verification, or simple location sharing.\n\n### \u2699\ufe0f How to use\n- Add your own webhook URLs or run locally\n- Pass query parameters to trigger either route\n- Both encode/decode logic is handled inside Function nodes\n\nNo credentials, APIs, or setup required.\n" }, "typeVersion": 1 } ], "active": true, "settings": { "executionOrder": "v1" }, "versionId": "9226c009-d942-4f3c-b982-9f7dbb73d710", "connections": { "Decode_Webhook": { "main": [ [ { "node": "DIGIPIN_Decode_Code", "type": "main", "index": 0 } ] ] }, "Encode_Webhook": { "main": [ [ { "node": "DIGIPIN_Generation_Code", "type": "main", "index": 0 } ] ] }, "DIGIPIN_Decode_Code": { "main": [ [ { "node": "Switch 2 - Check for Success1", "type": "main", "index": 0 } ] ] }, "DIGIPIN_Generation_Code": { "main": [ [ { "node": "Switch - Check for Success", "type": "main", "index": 0 } ] ] }, "Switch - Check for Success": { "main": [ [ { "node": "Respond to Webhook - Success", "type": "main", "index": 0 } ], [ { "node": "Respond to Webhook - Error", "type": "main", "index": 0 } ] ] }, "Switch 2 - Check for Success1": { "main": [ [ { "node": "Respond to Webhook - Success 2", "type": "main", "index": 0 } ], [ { "node": "Respond to Webhook - Error 2", "type": "main", "index": 0 } ] ] } } }