Add DB interface module for talking to the DB directly

Signed-off-by: Matthias Beyer <mail@beyermatthias.de>

2 files changed, 112 insertions, 0 deletions

diff --git a/src/db/interface.rs b/src/db/interface.rs
new file mode 100644
index 0000000..65a46ad
--- /dev/null
+++ b/src/db/interface.rs
@@ -0,0 +1,110 @@
+use std::path::PathBuf;
+
+use clap_v3 as clap;
+use clap::ArgMatches;
+use anyhow::anyhow;
+use anyhow::Context;
+use anyhow::Error;
+use anyhow::Result;
+
+use crate::config::Configuration;
+use crate::db::DbConnectionConfig;
+
+pub fn interface(db_connection_config: DbConnectionConfig, matches: &ArgMatches, config: &Configuration) -> Result<()> {
+    match matches.subcommand() {
+        ("cli", Some(matches))        => cli(db_connection_config, matches, config),
+        (other, _) => return Err(anyhow!("Unknown subcommand: {}", other)),
+    }
+}
+
+fn cli(db_connection_config: DbConnectionConfig, matches: &ArgMatches, config: &Configuration) -> Result<()> {
+    use std::process::Command;
+
+    trait PgCliCommand {
+        fn run_for_uri(&self, dbcc: DbConnectionConfig)  -> Result<()>;
+    }
+
+    struct Psql(PathBuf);
+    impl PgCliCommand for Psql {
+        fn run_for_uri(&self, dbcc: DbConnectionConfig)  -> Result<()> {
+            Command::new(&self.0)
+                .arg(format!("--dbname={}", dbcc.database_name()))
+                .arg(format!("--host={}", dbcc.database_host()))
+                .arg(format!("--port={}", dbcc.database_port()))
+                .arg(format!("--username={}", dbcc.database_user()))
+                .stdin(std::process::Stdio::inherit())
+                .stdout(std::process::Stdio::inherit())
+                .stderr(std::process::Stdio::inherit())
+                .output()
+                .map_err(Error::from)
+                .and_then(|out| {
+                    if out.status.success() {
+                        info!("pgcli exited successfully");
+                        Ok(())
+                    } else {
+                        Err(anyhow!("gpcli did not exit successfully"))
+                            .with_context(|| {
+                                match String::from_utf8(out.stderr) {
+                                    Ok(log) => anyhow!("{}", log),
+                                    Err(e)  => anyhow!("Cannot parse log into valid UTF-8: {}", e),
+                                }
+                            })
+                            .map_err(Error::from)
+                    }
+                })
+        }
+    }
+
+    struct PgCli(PathBuf);
+    impl PgCliCommand for PgCli {
+        fn run_for_uri(&self, dbcc: DbConnectionConfig)  -> Result<()> {
+            Command::new(&self.0)
+                .arg("--host")
+                .arg(dbcc.database_host())
+                .arg("--port")
+                .arg(dbcc.database_port())
+                .arg("--username")
+                .arg(dbcc.database_user())
+                .arg(dbcc.database_name())
+                .stdin(std::process::Stdio::inherit())
+                .stdout(std::process::Stdio::inherit())
+                .stderr(std::process::Stdio::inherit())
+                .output()
+                .map_err(Error::from)
+                .and_then(|out| {
+                    if out.status.success() {
+                        info!("pgcli exited successfully");
+                        Ok(())
+                    } else {
+                        Err(anyhow!("gpcli did not exit successfully"))
+                            .with_context(|| {
+                                match String::from_utf8(out.stderr) {
+                                    Ok(log) => anyhow!("{}", log),
+                                    Err(e)  => anyhow!("Cannot parse log into valid UTF-8: {}", e),
+                                }
+                            })
+                            .map_err(Error::from)
+                    }
+                })
+
+        }
+    }
+
+
+    matches.value_of("tool")
+        .map(|s| vec![s])
+        .unwrap_or_else(|| vec!["psql", "pgcli"])
+        .into_iter()
+        .filter_map(|s| which::which(&s).ok().map(|path| (path, s)))
+        .map(|(path, s)| {
+            match s {
+                "psql"  => Ok(Box::new(Psql(path)) as Box<dyn PgCliCommand>),
+                "pgcli" => Ok(Box::new(PgCli(path)) as Box<dyn PgCliCommand>),
+                prog    => Err(anyhow!("Unsupported pg CLI program: {}", prog)),
+            }
+        })
+        .next()
+        .transpose()?
+        .ok_or_else(|| anyhow!("No Program found"))?
+        .run_for_uri(db_connection_config)
+}
diff --git a/src/db/mod.rs b/src/db/mod.rs
index 95074cb..322d168 100644
--- a/src/db/mod.rs
+++ b/src/db/mod.rs
@@ -4,3 +4,5 @@ pub use connection::*;
 mod cli;
 pub use cli::*;
 
+mod interface;
+pub use interface::*;