add support for pre_start and post_start scripts

README.md

@@ -225,13 +225,20 @@ name = "homepage"
 runs_on = ["docker1"]
 # It requires that the traefik stack on docker1 be deployed first
 depends_on = ["traefik"]
+# It has a pre-start script that should be run before the stack is started
+pre_start = ["./pre_start"]
+# It has a post-script that should be run after the stack is started
+post_start = ["./post_start"]
 ```
 
 The stacks are topologically sorted based on their dependencies and then
 started in that order.
 
 It is not possible to depend on stacks that are running on other hosts.
 
+`pre_start` and `post_start` scripts can be run to do any necessary setup such
+as creating network resources.
+
 ## Stopping and removing a Stack
 
 This is a two phase process:

src/deploy_file.rs

@@ -26,6 +26,14 @@ pub struct StackDeploy {
     #[serde(default)]
     pub secret_env: BTreeMap<String, String>,
 
+    /// List of scripts to run before starting the stack
+    #[serde(default)]
+    pub pre_start: Vec<String>,
+
+    /// List of scripts to run after starting the stack
+    #[serde(default)]
+    pub post_start: Vec<String>,
+
     // TODO: secret_file
     /// List of host names on which to run this service
     pub runs_on: Vec<String>,

src/main.rs

@@ -155,10 +155,47 @@ fn do_compose_up(db: &KeePassDB, path: &Path, deploy: &StackDeploy) -> anyhow::R
         "Cannot deploy {path:?} because of the errors above"
     );
 
+    if !&deploy.pre_start.is_empty() {
+        let mut cmd = std::process::Command::new(&deploy.pre_start[0]);
+        cmd.current_dir(
+            path.parent()
+                .ok_or_else(|| anyhow::anyhow!("path {path:?} has no parent!?"))?,
+        );
+        for script in &deploy.pre_start[1..] {
+            cmd.arg(script);
+        }
+        for (k, v) in deploy.secret_env.iter() {
+            db.resolve_value(&v).map(|v| cmd.env(k, v));
+        }
+        let status = cmd
+            .status()
+            .with_context(|| format!("failed to run pre_start script in directory of {path:?}"))?;
+        anyhow::ensure!(status.success(), "pre_script exit status is {status:?}");
+    }
+
     let status = cmd
         .status()
         .with_context(|| format!("failed to run docker compose up in directory of {path:?}"))?;
     anyhow::ensure!(status.success(), "exit status is {status:?}");
+
+    if !&deploy.post_start.is_empty() {
+        let mut cmd = std::process::Command::new(&deploy.pre_start[0]);
+        cmd.current_dir(
+            path.parent()
+                .ok_or_else(|| anyhow::anyhow!("path {path:?} has no parent!?"))?,
+        );
+        for script in &deploy.post_start[1..] {
+            cmd.arg(script);
+        }
+        for (k, v) in deploy.secret_env.iter() {
+            db.resolve_value(&v).map(|v| cmd.env(k, v));
+        }
+        let status = cmd
+            .status()
+            .with_context(|| format!("failed to run post_start script in directory of {path:?}"))?;
+        anyhow::ensure!(status.success(), "post_start exit status is {status:?}");
+    }
+
     Ok(())
 }