Configure CloudFront proxy for Tilegarden

common.yml

@@ -17,6 +17,7 @@ services:
       - PFB_AWS_BATCH_TILEMAKER_JOB_QUEUE_NAME
       - PFB_AWS_BATCH_TILEMAKER_JOB_DEFINITION_NAME_REVISION
       - PFB_AWS_BATCH_TILEMAKER_JOB_DEFINITION_NAME
+      - PFB_TILEGARDEN_ROOT=http://localhost:9400
     volumes:
       - $HOME/.aws:/root/.aws:ro
 

deployment/README.md

@@ -9,6 +9,7 @@ Amazon Web Services deployment is driven by [Terraform](https://terraform.io/) a
 * [AWS Credentials](#aws-credentials)
 * [Terraform](#terraform)
 * [AWS Batch](#aws-batch)
+* [Tilegarden](#tilegarden)
 
 ## AWS Credentials
 
@@ -82,3 +83,88 @@ Click 'Create queue' again and follow the same steps to create a second queue na
 Once the unmanaged compute environment has a 'VALID' status, navigate to [EC2 Container Service](https://console.aws.amazon.com/ecs/home?region=us-east-1) and copy the full name of the newly created ECS Cluster into the `batch_ecs_cluster_name` tfvar for the appropriate environment.
 
 Congratulations, the necessary resources for your environment are ready. The ECS instance configuration and autoscaling group attached to the compute environment are managed by Terraform.
+
+## Tilegarden
+
+We serve map tiles using [Tilegarden](https://github.com/azavea/tilegarden), a
+serverless tile generator that runs on AWS Lambda. Portions of Tilegarden
+are deployed separately from the Terraform stack because Tilegarden
+is tightly coupled with [Claudia](https://claudiajs.com/), an opinionated
+deployment tool for publishing Node code as Lambda functions. The main
+components of Tilegarden that are deployed this way include a Lambda function
+and an API Gateway.
+
+CI will deploy updates to existing Tilegarden instances automatically, but there are
+a few extra steps you'll need to take in order to stand up an entirely new
+instance of Tilegarden. Because Terraform expects a Tilegarden instance to
+exist before it creates infrastructure, **it's best to finish these steps before
+you deploy a new stack with Terraform**.
+
+### 1. Create a remote state bucket for Claudia
+
+Remote state for Claudia should exist in the same S3 bucket as Terraform remote
+state. For staging, this bucket should be something like `staging-pfb-config-us-east-1`.
+In that bucket, create a new folder (that is, an object prefix) for
+Tilegarden remote state called `tilegarden/`.
+
+### 2. Configure environment variables for your function
+
+Tilegarden uses an `.env` file in order to pass environment variables into
+the Lambda function. Copy over the example file to create a new one:
+
+```
+$ cp ./src/tilegarden/.env.example ./src/tilegarden/.env
+```
+
+The three required variables are `AWS_PROFILE`, `PROJECT_NAME`, and
+`LAMBDA_REGION`. Other optional variables can be uncommented and edited to
+reflect your configuration. If you need Tilegarden to access a database, for
+example, you'll likely want to set `LAMBDA_SUBNETS` and `LAMBDA_SECURITY_GROUPS` to point
+to the relevant resources in your VPC.
+
+If you have any additional environment variables (like database connection
+strings) that you need access to in your function, add them to `./src/tilegarden/.env`
+and they will be passed in during deployment.
+
+### 3. Deploy a new Tilegarden instance with Claudia
+
+Before deploying your instance, `touch` a file that Claudia can use to save
+deployment metadata:
+
+```
+$ touch ./src/tilegarden/claudia.json
+```
+
+Next, use the Tilegarden Node scripts in the VM to deploy a new Tilegarden instance:
+
+```
+vagrant@pfb-network-connectivity:/vagrant$ docker-compose \
+                                             -f docker-compose.yml \
+                                             -f docker-compose.test.yml \
+                                             run --rm --entrypoint yarn \
+                                             tilegarden deploy-new
+```
+
+### 4. Update remote state for Claudia and Terraform
+
+Once the deployment has completed, upload your `.env` file and Claudia metadata
+file to the remote state bucket so that CI can update Tilegarden automatically:
+
+```
+$ aws s3 cp ./src/tilegarden/.env s3://<remote-state-bucket>/tilegarden/.env
+$ aws s3 cp ./src/tilegarden/claudia.json s3://<remote-state-bucket>/tilegarden/claudia.json
+```
+
+In addition, edit the remote Terraform variables in `terraform.tfvars` for your
+deployment to point to the domain name for the new API Gateway that Claudia has created.
+The variable for the API Gateway should look something like this:
+
+```hcl
+# Tilegarden
+tilegarden_api_gateway_domain_name = "<api.id>.execute-api.<lambda.region>.amazonaws.com"
+```
+
+You can locate this domain name in the Lambda console, or you can construct it
+by using the `api.id` and `lambda.region` values stored in the `claudia.json` file
+that Claudia created during deployment to format the example string in the
+code block above.

deployment/terraform/app.tf

@@ -152,6 +152,7 @@ data "template_file" "pfb_app_https_ecs_task" {
     batch_analysis_job_definition_name_revision  = "${var.batch_analysis_job_definition_name_revision}"
     batch_tilemaker_job_queue_name               = "${var.batch_tilemaker_job_queue_name}"
     batch_tilemaker_job_definition_name_revision = "${var.batch_tilemaker_job_definition_name_revision}"
+    tilegarden_root                              = "https://${aws_cloudfront_distribution.tilegarden.domain_name}"
   }
 }
 
@@ -197,6 +198,7 @@ data "template_file" "pfb_app_async_queue_ecs_task" {
     batch_analysis_job_definition_name_revision  = "${var.batch_analysis_job_definition_name_revision}"
     batch_tilemaker_job_queue_name               = "${var.batch_tilemaker_job_queue_name}"
     batch_tilemaker_job_definition_name_revision = "${var.batch_tilemaker_job_definition_name_revision}"
+    tilegarden_root                              = "https://${aws_cloudfront_distribution.tilegarden.domain_name}"
   }
 }
 
@@ -235,6 +237,7 @@ data "template_file" "pfb_app_management_ecs_task" {
     batch_analysis_job_definition_name_revision  = "${var.batch_analysis_job_definition_name_revision}"
     batch_tilemaker_job_queue_name               = "${var.batch_tilemaker_job_queue_name}"
     batch_tilemaker_job_definition_name_revision = "${var.batch_tilemaker_job_definition_name_revision}"
+    tilegarden_root                              = "https://${aws_cloudfront_distribution.tilegarden.domain_name}"
   }
 }
 

deployment/terraform/cdn.tf

@@ -0,0 +1,54 @@
+resource "aws_cloudfront_distribution" "tilegarden" {
+  origin {
+    custom_origin_config {
+      http_port              = 80
+      https_port             = 443
+      origin_protocol_policy = "https-only"
+      origin_ssl_protocols   = ["TLSv1.2", "TLSv1.1", "TLSv1"]
+    }
+
+    domain_name = "${var.tilegarden_api_gateway_domain_name}"
+    origin_path = "/latest"
+    origin_id   = "tilegardenOrigin${title(var.environment)}EastId"
+
+    custom_header {
+      name  = "Accept"
+      value = "image/png"
+    }
+  }
+
+  price_class     = "PriceClass_100"
+  enabled         = true
+  is_ipv6_enabled = true
+  comment         = "${var.project} (${var.environment})"
+
+  default_cache_behavior {
+    allowed_methods  = ["GET", "HEAD", "OPTIONS"]
+    cached_methods   = ["GET", "HEAD"]
+    target_origin_id = "tilegardenOrigin${title(var.environment)}EastId"
+
+    forwarded_values {
+      query_string = true
+
+      cookies {
+        forward = "none"
+      }
+    }
+
+    viewer_protocol_policy = "redirect-to-https"
+    min_ttl                = 0
+    default_ttl            = "300"               # Five minutes
+    max_ttl                = "86400"             # One day
+  }
+
+  restrictions {
+    "geo_restriction" {
+      restriction_type = "none"
+    }
+  }
+
+  viewer_certificate {
+    cloudfront_default_certificate = true
+    minimum_protocol_version       = "TLSv1"
+  }
+}

deployment/terraform/task-definitions/app.json

@@ -94,6 +94,10 @@
       {
         "name": "PFB_AWS_BATCH_TILEMAKER_JOB_DEFINITION_NAME_REVISION",
         "value": "${batch_tilemaker_job_definition_name_revision}"
+      },
+      {
+        "name": "PFB_TILEGARDEN_ROOT",
+        "value": "${tilegarden_root}"
       }
     ],
     "logConfiguration": {

deployment/terraform/task-definitions/django-q.json

@@ -77,6 +77,10 @@
         {
           "name": "PFB_AWS_BATCH_TILEMAKER_JOB_DEFINITION_NAME_REVISION",
           "value": "${batch_tilemaker_job_definition_name_revision}"
+        },
+        {
+            "name": "PFB_TILEGARDEN_ROOT",
+            "value": "${tilegarden_root}"
         }
       ],
       "logConfiguration": {

deployment/terraform/task-definitions/management.json

@@ -76,6 +76,10 @@
       {
         "name": "PFB_AWS_BATCH_TILEMAKER_JOB_DEFINITION_NAME_REVISION",
         "value": "${batch_tilemaker_job_definition_name_revision}"
+      },
+      {
+        "name": "PFB_TILEGARDEN_ROOT",
+        "value": "${tilegarden_root}"
       }
     ],
     "logConfiguration": {

deployment/terraform/variables.tf

@@ -157,3 +157,5 @@ variable "aws_cloudwatch_logs_policy_arn" {
 variable "pfb_app_alb_ingress_cidr_block" {
   type = "list"
 }
+
+variable "tilegarden_api_gateway_domain_name" {}

src/django/pfb_network_connectivity/settings.py

@@ -347,6 +347,6 @@
 PFB_ANALYSIS_PRESIGNED_URL_EXPIRES = 3600
 
 # Root URL for tile server.
-# TODO (probably with issue #595): this is the development answer. For staging/production
-#      we'll have to supply the URL of the actual deployed CloudFront distribution.
-TILEGARDEN_ROOT = 'http://localhost:9400'
+TILEGARDEN_ROOT = os.getenv('PFB_TILEGARDEN_ROOT')
+if not TILEGARDEN_ROOT:
+    raise ImproperlyConfigured('env.PFB_TILEGARDEN_ROOT is required')