Hook up the range data to the API

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 2
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = false
+insert_final_newline = true
+
+[*.rs]
+indent_size = 4

Cargo.lock

@@ -75,6 +75,12 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "either"
+version = "1.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e78d4f1cc4ae33bbfc157ed5d5a5ef3bc29227303d595861deb238fcec4e9457"
+
 [[package]]
 name = "fnv"
 version = "1.0.7"
@@ -147,6 +153,9 @@ dependencies = [
 name = "geoip-api"
 version = "0.1.0"
 dependencies = [
+ "itertools",
+ "serde",
+ "serde_json",
  "tokio",
  "warp",
 ]
@@ -309,6 +318,15 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "itertools"
+version = "0.10.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a9a9d19fa1e79b6215ff29b9d6880b706147f16e9b1dbb1e4e5947b5b02bc5e3"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "itoa"
 version = "0.4.8"
@@ -630,6 +648,20 @@ name = "serde"
 version = "1.0.132"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8b9875c23cf305cd1fd7eb77234cbb705f21ea6a72c637a5c6db5fe4b8e7f008"
+dependencies = [
+ "serde_derive",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.132"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ecc0db5cb2556c0e558887d9bbdcf6ac4471e83ff66cf696e5419024d1606276"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
 
 [[package]]
 name = "serde_json"

Cargo.toml

@@ -5,5 +5,8 @@ edition = "2021"
 authors = ["charlotte ✨ <charlotte@lavender.software>"]
 
 [dependencies]
+itertools = "0.10.3"
+serde = { version = "1.0.132", features = ["derive"] }
+serde_json = "1.0.73"
 tokio = { version = "1.15.0", features = ["full"] }
 warp = "0.3.2"

README.md

@@ -0,0 +1,25 @@
+# geoip-api
+
+HTTP API for converting an IPv4 address to a country code.
+
+Uses the [`iptoasn.com`](https://iptoasn.com) dataset.
+
+## Setup
+
+Grab the latest `ip2asn-v4.tsv.gz` and extract it to `data/ip2asn-v4.tsv`.
+
+Then just use `cargo` as usual.
+
+## Usage
+
+```shell
+$ http GET 'http://127.0.0.1:8000/192.168.0.1'
+```
+
+```json
+{
+  "asn": 0,
+  "country_code": "None",
+  "asn_desc": "Not routed"
+}
+```

data/.gitignore

@@ -0,0 +1,2 @@
+*
+!.gitignore

src/main.rs

@@ -1,7 +1,85 @@
-use warp::Filter;
+use itertools::Itertools;
+use serde::Serialize;
+use std::{net::Ipv4Addr, sync::Arc};
+
+use warp::{http::StatusCode, reply, Filter};
+
+use serde_json::json;
+
+const IP2ASN_DATA: &str = include_str!("../data/ip2asn-v4.tsv");
+
+#[derive(Serialize)]
+struct RangeRecord {
+    #[serde(skip)]
+    ip_start: Ipv4Addr,
+    #[serde(skip)]
+    ip_end: Ipv4Addr,
+    asn: u64,
+    country_code: &'static str,
+    asn_description: &'static str,
+}
+
+fn parse_ranges() -> Vec<RangeRecord> {
+    let mut ranges = Vec::with_capacity(IP2ASN_DATA.lines().count());
+
+    IP2ASN_DATA
+        .lines()
+        .filter(|s| !s.is_empty())
+        .map(|l| {
+            l.splitn(5, '\t')
+                .next_tuple::<(&str, &str, &str, &str, &str)>()
+                .unwrap()
+        })
+        .for_each(|(ip_start, ip_end, asn, country_code, asn_description)| {
+            ranges.push(RangeRecord {
+                ip_start: ip_start.parse().unwrap(),
+                ip_end: ip_end.parse().unwrap(),
+                asn: asn.parse().unwrap(),
+                country_code,
+                asn_description,
+            })
+        });
+
+    ranges
+}
+
+type RangeData = Arc<Vec<RangeRecord>>;
+fn with_ranges(
+    ranges: RangeData,
+) -> impl Filter<Extract = (RangeData,), Error = std::convert::Infallible> + Clone {
+    warp::any().map(move || ranges.clone())
+}
+
+fn get_range_data(ip: String, ranges: RangeData) -> impl warp::Reply {
+    if let Ok(ipv4) = ip.parse::<Ipv4Addr>() {
+        for range in ranges.iter() {
+            if (range.ip_start..=range.ip_end).contains(&ipv4) {
+                return reply::with_status(reply::json(&range), StatusCode::OK);
+            }
+        }
+
+        reply::with_status(
+            reply::json(&json!({ "error": "range not found" })),
+            StatusCode::NOT_FOUND,
+        )
+    } else {
+        reply::with_status(
+            reply::json(&json!({ "error": "invalid ipv4 address" })),
+            StatusCode::BAD_REQUEST,
+        )
+    }
+}
 
 #[tokio::main]
 async fn main() {
-    let hello = warp::any().map(|| "Hello!".to_string());
-    warp::serve(hello).bind(([127, 0, 0, 1], 8000)).await;
+    eprintln!("[i] Parsing IP ASN data...");
+    let ranges: RangeData = Arc::new(parse_ranges());
+    eprintln!("[i] Done!");
+
+    let get_ip_data = warp::path!(String)
+        .and(with_ranges(ranges.clone()))
+        .map(get_range_data);
+
+    println!("\nListening on http://127.0.0.1:8000 ...");
+    warp::serve(get_ip_data).bind(([127, 0, 0, 1], 8000)).await;
 }