Make it possible to propagate correlation ID across processessh-extract-context-from-env

Previously, gitlab-shell did not pass a context through the application.
Correlation IDs were generated down the call stack, since we don't pass
the context around from the start execution.

This has several potential downsides:

1. It's easier for programming mistakes to be made in future which lead
to multiple correlation IDs being generated for a single request.
2. Correlation IDs cannot be passed in from upstream requests
3. Other advantages of context passing, such as distributed tracing is
not possible.

This commit changes the behavior:

1. Extract the correlation ID from the environment at the start of
the application.
2. If no correlation ID exists, generate a random one.
3. Pass the correlation ID to the GitLabNet API requests.

This change also enables other clients of GitLabNet (e.g. Gitaly) to
pass along the correlation ID in the internal API requests
(https://gitlab.com/gitlab-org/gitaly/-/issues/2725).

Fixes https://gitlab.com/gitlab-org/gitlab-shell/-/issues/474

1 files changed, 11 insertions, 10 deletions

diff --git a/client/client_test.go b/client/client_test.go
index e92093a..e0650b2 100644
--- a/client/client_test.go
+++ b/client/client_test.go
@@ -1,6 +1,7 @@
 package client
 
 import (
+	"context"
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
@@ -78,7 +79,7 @@ func TestClients(t *testing.T) {
 func testSuccessfulGet(t *testing.T, client *GitlabNetClient) {
 	t.Run("Successful get", func(t *testing.T) {
 		hook := testhelper.SetupLogger()
-		response, err := client.Get("/hello")
+		response, err := client.Get(context.Background(), "/hello")
 		require.NoError(t, err)
 		require.NotNil(t, response)
 
@@ -104,7 +105,7 @@ func testSuccessfulPost(t *testing.T, client *GitlabNetClient) {
 		hook := testhelper.SetupLogger()
 		data := map[string]string{"key": "value"}
 
-		response, err := client.Post("/post_endpoint", data)
+		response, err := client.Post(context.Background(), "/post_endpoint", data)
 		require.NoError(t, err)
 		require.NotNil(t, response)
 
@@ -128,7 +129,7 @@ func testSuccessfulPost(t *testing.T, client *GitlabNetClient) {
 func testMissing(t *testing.T, client *GitlabNetClient) {
 	t.Run("Missing error for GET", func(t *testing.T) {
 		hook := testhelper.SetupLogger()
-		response, err := client.Get("/missing")
+		response, err := client.Get(context.Background(), "/missing")
 		assert.EqualError(t, err, "Internal API error (404)")
 		assert.Nil(t, response)
 
@@ -144,7 +145,7 @@ func testMissing(t *testing.T, client *GitlabNetClient) {
 
 	t.Run("Missing error for POST", func(t *testing.T) {
 		hook := testhelper.SetupLogger()
-		response, err := client.Post("/missing", map[string]string{})
+		response, err := client.Post(context.Background(), "/missing", map[string]string{})
 		assert.EqualError(t, err, "Internal API error (404)")
 		assert.Nil(t, response)
 
@@ -161,13 +162,13 @@ func testMissing(t *testing.T, client *GitlabNetClient) {
 
 func testErrorMessage(t *testing.T, client *GitlabNetClient) {
 	t.Run("Error with message for GET", func(t *testing.T) {
-		response, err := client.Get("/error")
+		response, err := client.Get(context.Background(), "/error")
 		assert.EqualError(t, err, "Don't do that")
 		assert.Nil(t, response)
 	})
 
 	t.Run("Error with message for POST", func(t *testing.T) {
-		response, err := client.Post("/error", map[string]string{})
+		response, err := client.Post(context.Background(), "/error", map[string]string{})
 		assert.EqualError(t, err, "Don't do that")
 		assert.Nil(t, response)
 	})
@@ -177,7 +178,7 @@ func testBrokenRequest(t *testing.T, client *GitlabNetClient) {
 	t.Run("Broken request for GET", func(t *testing.T) {
 		hook := testhelper.SetupLogger()
 
-		response, err := client.Get("/broken")
+		response, err := client.Get(context.Background(), "/broken")
 		assert.EqualError(t, err, "Internal API unreachable")
 		assert.Nil(t, response)
 
@@ -194,7 +195,7 @@ func testBrokenRequest(t *testing.T, client *GitlabNetClient) {
 	t.Run("Broken request for POST", func(t *testing.T) {
 		hook := testhelper.SetupLogger()
 
-		response, err := client.Post("/broken", map[string]string{})
+		response, err := client.Post(context.Background(), "/broken", map[string]string{})
 		assert.EqualError(t, err, "Internal API unreachable")
 		assert.Nil(t, response)
 
@@ -211,7 +212,7 @@ func testBrokenRequest(t *testing.T, client *GitlabNetClient) {
 
 func testAuthenticationHeader(t *testing.T, client *GitlabNetClient) {
 	t.Run("Authentication headers for GET", func(t *testing.T) {
-		response, err := client.Get("/auth")
+		response, err := client.Get(context.Background(), "/auth")
 		require.NoError(t, err)
 		require.NotNil(t, response)
 
@@ -226,7 +227,7 @@ func testAuthenticationHeader(t *testing.T, client *GitlabNetClient) {
 	})
 
 	t.Run("Authentication headers for POST", func(t *testing.T) {
-		response, err := client.Post("/auth", map[string]string{})
+		response, err := client.Post(context.Background(), "/auth", map[string]string{})
 		require.NoError(t, err)
 		require.NotNil(t, response)