Allow including secondary output from libpostal

We add a new command-line flag allowing the user
to combine regular geocoder output with columns
from libpostal.

src/geocoders/libpostal.rs

@@ -9,7 +9,7 @@ use crate::{addresses::Address, Result};
 
 use super::{Geocoded, Geocoder};
 
-static COLUMN_NAMES: &[&str] = &[
+pub(crate) static COLUMN_NAMES: &[&str] = &[
     // From
     // https://github.com/OpenCageData/address-formatting/blob/master/conf/components.yaml.
     "archipelago",

src/geocoders/mod.rs

@@ -19,6 +19,7 @@ pub mod cache;
 pub mod invalid_record_skipper;
 pub mod libpostal;
 pub mod normalizer;
+pub mod paired;
 pub mod smarty;
 
 /// A `hyper` client shared between multiple workers.

src/geocoders/paired.rs

@@ -0,0 +1,65 @@
+//! Paired geocoder. Run two geocoders, return both.
+//!
+//! ¿Por qué no los dos?
+
+use async_trait::async_trait;
+
+use crate::geocoders::{Geocoded, Geocoder};
+use crate::{addresses::Address, Result};
+
+/// A geocoder that runs two geocoders and returns both results.
+pub struct Paired {
+    /// The first geocoder.
+    fst: Box<dyn Geocoder>,
+    /// The second geocoder.
+    snd: Box<dyn Geocoder>,
+    /// The column names output by this geocoder. Includes both sets
+    /// of column names.
+    column_names: Vec<String>,
+    /// The configuration key for this geocoder.
+    config_key: String,
+}
+
+impl Paired {
+    /// Create a new pair of geocoders.
+    pub fn new(fst: Box<dyn Geocoder>, snd: Box<dyn Geocoder>) -> Paired {
+        let column_names = fst
+            .column_names()
+            .iter()
+            .chain(snd.column_names())
+            .cloned()
+            .collect();
+        let config_key =
+            format!("{}+{}", fst.configuration_key(), snd.configuration_key());
+        Paired {
+            fst,
+            snd,
+            column_names,
+            config_key,
+        }
+    }
+}
+
+#[async_trait]
+impl Geocoder for Paired {
+    fn tag(&self) -> &str {
+        "pair"
+    }
+
+    fn configuration_key(&self) -> &str {
+        &self.config_key
+    }
+
+    fn column_names(&self) -> &[String] {
+        &self.column_names
+    }
+
+    async fn geocode_addresses(
+        &self,
+        addresses: &[Address],
+    ) -> Result<Vec<Option<Geocoded>>> {
+        let fst = self.fst.geocode_addresses(addresses).await?;
+        let snd = self.snd.geocode_addresses(addresses).await?;
+        Ok(fst.into_iter().chain(snd.into_iter()).collect())
+    }
+}

src/main.rs

@@ -33,7 +33,6 @@ mod pipeline;
 mod server;
 mod unpack_vec;
 
-use crate::addresses::AddressColumnSpec;
 use crate::geocoders::{
     cache::Cache, invalid_record_skipper::InvalidRecordSkipper, libpostal::LibPostal,
     normalizer::Normalizer, shared_http_client, smarty::Smarty, Geocoder,
@@ -42,6 +41,7 @@ use crate::geocoders::{
 use crate::key_value_stores::KeyValueStore;
 use crate::pipeline::{geocode_stdio, OnDuplicateColumns, CONCURRENCY, GEOCODE_SIZE};
 use crate::server::run_server;
+use crate::{addresses::AddressColumnSpec, geocoders::paired::Paired};
 
 #[cfg(all(feature = "jemallocator", not(target_env = "msvc")))]
 #[global_allocator]
@@ -143,6 +143,10 @@ struct Opt {
     #[arg(long = "normalize")]
     normalize: bool,
 
+    /// Include normalization-related columns.
+    #[arg(long = "include-normalizer-columns", requires = "normalize")]
+    include_normalizer_columns: bool,
+
     /// Limit the speed with which we access external geocoding APIs. Does not
     /// affect the cache or local geocoding.
     #[arg(long = "max-addresses-per-second")]
@@ -272,7 +276,11 @@ async fn main() -> Result<()> {
 
     // If we were asked, normalize addresses a bit first.
     if opt.normalize {
-        geocoder = Box::new(Normalizer::new(geocoder));
+        let normalizer = Normalizer::new(geocoder);
+        geocoder = Box::new(normalizer);
+        if opt.include_normalizer_columns {
+            geocoder = Box::new(Paired::new(geocoder, Box::new(LibPostal::new())));
+        }
     }
 
     // Decide which command to run.