Add documentation for configuring Maven with a private repository for… (#704)

… SCIP-JAVA private-maven-repository-configuration-scip-java.mdx

- Added a new Markdown file detailing the steps to configure Maven to
use a private Nexus or Artifactory repository for SCIP-JAVA indexing.
- Includes guidance for single repository testing and automated
configuration across multiple repositories via Sourcegraph's Lua
inference script.
- Docs placed under the Code Navigation section to aid users in secure
dependency management for SCIP-JAVA.

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---------

Co-authored-by: Anton Sviridov <anton.sviridov@sourcegraph.com>
Co-authored-by: Maedah Batool <me@MaedahBatool.com>

Author: 3 people

docs/code-search/code-navigation/private-maven-repository-configuration.mdx

@@ -0,0 +1,94 @@
+# Configuring Maven to Use a Private Repository for Auto-Indexing
+
+Configuring Maven to use a private repository, such as Nexus or Artifactory, with Sourcegraph is essential when dependencies are retrieved from private repositories that require authentication (as opposed to public repositories such as Maven Central). This guide covers steps to set up Maven for [scip-java](https://sourcegraph.github.io/scip-java/) indexing with a private repository, ensuring secure and consistent dependency resolution.
+
+## Testing the Configuration on a Single Repository
+
+To test and validate the Maven configuration, modify a single repository’s auto-indexing settings to include a custom settings.xml file. Refer to (Maven's official docs)[https://maven.apache.org/settings.html#quick-overview] for an overview of how this file is used to configure Maven repositories and other settings.
+
+### Add Custom Index Job Configuration
+
+- Access the repository’s index settings in Sourcegraph and open the “Raw” configuration panel.
+- Insert the following configuration:
+
+     ```json
+     {
+       "steps": [],
+       "local_steps": [
+         "mkdir -p ~/.m2",
+         "echo '<settings xmlns=\"http://maven.apache.org/SETTINGS/1.0.0\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:schemaLocation=\"http://maven.apache.org/SETTINGS/1.0.0 https://maven.apache.org/xsd/settings-1.0.0.xsd\"> <servers> <server> <id>repo</id> <username>$ARTIFACTORY_USER</username> <password>$ARTIFACTORY_PASSWORD</password> </server> </servers> </settings>' > ~/.m2/settings.xml"
+       ],
+       "root": "",
+       "indexer": "sourcegraph/scip-java:latest",
+       "indexer_args": [
+         "scip-java",
+         "index",
+         "--build-tool=auto"
+       ],
+       "outfile": "index.scip",
+       "requestedEnvVars": [
+         "ARTIFACTORY_USER",
+         "ARTIFACTORY_PASSWORD"
+       ]
+     }
+     ```
+
+### Set Up Executor Secrets
+
+Before triggering the indexing process, make sure the environment variables `$ARTIFACTORY_USER` and `$ARTIFACTORY_PASSWORD` are created as [Executor Secrets](https://sourcegraph.com/docs/admin/executors/executor_secrets).
+
+### Trigger Indexing
+
+After configuring the repository, navigate to the "Precise Indexes" tab and click "Enqueue" to start indexing.
+
+## Automating the Configuration Across All Repositories
+
+After verifying the configuration on a single repository, you can automate the setup across all repositories by modifying the inference configuration using a Lua script.
+
+### Create or Update the Lua Script
+
+Navigate to `site-admin -> Code Graph -> Inference`, and replace or add the following Lua script for [scip-java](https://sourcegraph.github.io/scip-java/) indexing with Maven’s `settings.xml` setup:
+
+```lua
+local path = require("path")
+local pattern = require("sg.autoindex.patterns")
+local recognizer = require("sg.autoindex.recognizer")
+local patterns = require "internal_patterns"
+
+local new_steps = {
+    'mkdir -p ~/.m2',
+    [[echo "<?xml version=\"1.0\"?><settings xmlns=\"http://maven.apache.org/SETTINGS/1.0.0\"><servers><server><id>repo</id><username>$ARTIFACTORY_USER</username><password>$ARTIFACTORY_PASSWORD</password></server></servers></settings>" > ~/.m2/settings.xml]]
+}
+
+local new_requested_env_variables = {'ARTIFACTORY_USER', 'ARTIFACTORY_PASSWORD'}
+local java_indexer = require("sg.autoindex.indexes").get "java"
+
+local custom_java_recognizer = recognizer.new_path_recognizer {
+    patterns = {
+        pattern.new_path_basename("pom.xml"),
+        pattern.new_path_basename("build.gradle"),
+        pattern.new_path_basename("build.gradle.kts"),
+ },
+    generate = function(api, paths)
+        api:register({
+            local_steps = new_steps,
+            requested_envvars = new_requested_env_variables,
+            root = path.dirname(paths[1]),
+            outfile = "index.scip",
+            indexer = java_indexer,
+            indexer_args = { "scip-java", "index", "--build-tool=auto" }
+ })
+    end
+}
+
+return require("sg.autoindex.config").new({
+ ["custom.java"] = custom_java_recognizer,
+ ["sg.java"] = false
+})
+```
+
+### Verify the Configuration
+
+Once the Lua script is applied, you can verify that the configuration works by using the **"Preview results"** button in the Lua script editor under the "Inference Configuration" section. This will display the inferred index jobs for your repositories, showing details such as the root directory, indexer, indexer arguments, and environment variables used for each job.
+
+If everything is configured correctly, the dependencies will be pulled from the specified private repository without issues.