enclave_build: start replacing shiplift with bollard

Introduce the image_exists private method utilizing Bollard to check whether
a docker image exists locally.

Signed-off-by: Erdem Meydanli <[email protected]>

enclave_build/src/docker.rs

@@ -3,6 +3,7 @@
 
 use crate::docker::DockerError::CredentialsError;
 use base64::{engine::general_purpose, Engine as _};
+use bollard::errors::Error;
 use futures::stream::StreamExt;
 use log::{debug, error, info};
 use serde_json::{json, Value};
@@ -33,6 +34,7 @@ pub enum DockerError {
 /// Struct exposing the Docker functionalities to the EIF builder
 pub struct DockerUtil {
     docker: Docker,
+    docker2: bollard::Docker,
     docker_image: String,
 }
 
@@ -50,6 +52,8 @@ impl DockerUtil {
             // if docker daemon address needs to be substituted.
             // By default it tries to connect to 'unix:///var/run/docker.sock'
             docker: Docker::new(),
+            docker2: bollard::Docker::connect_with_socket_defaults()
+                .expect("Failed to connect to Docker daemon"),
             docker_image,
         }
     }
@@ -155,23 +159,36 @@ impl DockerUtil {
         }
     }
 
+    async fn image_exists(&self) -> Result<bool, Error> {
+/*
+        self.docker
+            .images()
+            .get(&self.docker_image)
+            .inspect()
+            .await
+            .is_ok()
+*/
+        let result = self.docker2.inspect_image(&self.docker_image).await?;
+
+        let tag_matches = result
+            .repo_tags
+            .as_ref()
+            .unwrap()
+            .iter()
+            .any(|repo_tag| repo_tag == &self.docker_image);
+
+        Ok(tag_matches)
+    }
+
     /// Pull the image, with the tag provided in constructor, from the Docker registry
     pub fn pull_image(&self) -> Result<(), DockerError> {
         let act = async {
             // Check if the Docker image is locally available.
             // If available, early exit.
-            if self
-                .docker
-                .images()
-                .get(&self.docker_image)
-                .inspect()
-                .await
-                .is_ok()
-            {
+            if self.image_exists().await.is_ok() {
                 eprintln!("Using the locally available Docker image...");
                 return Ok(());
             }
-
             let mut pull_options_builder = PullOptions::builder();
             pull_options_builder.image(&self.docker_image);