Skip to content

.gama files deployment#

Flows management often incurs several tasks such as manual upload of UI templates and web assets plus java source files, and interaction with a REST API for the CRUD of flows themselves. Here, an alternative mechanism for deployment is described where several flows can be supplied alongside their assets and metadata in a single bundle for bulk processing at the server.

This mechanism may facilitate developers' work when multiple flows need to be manipulated. Also it can be used in the development of tools that may serve as IDEs for Agama.

What's in an .gama file?#

A .gama file is an atomic deployment unit. It is an archive containing the several flows to deploy on the server plus related files and some metadata. This archive has to be "presented" to an API endpoint which takes charge of its processing.

The below shows the structure of an extracted .gama file (recall it has to originally follow the ZIP format):

├── code/
├── lib/           
├── web/
├── project.json   
├── LICENSE        
└── README.md      
  • code directory holds Agama code. Every flow has to reside in a separate file with extension flow and with file name matching the qualified name of the flow in question
  • lib can contain Java/Groovy source files and jar files. These are used to agument the classpath as explained here
  • web is expected to hold all UI templates plus required web assets (stylesheets, images, etc.) of all flows in this bundle
  • project.json file contains metadata about this bundle, like display name, description, etc. More on this later
  • README.md file may contain extra documentation in markdown format

Notes:

  • Except for code and web directories, all elements in the archive structure are optional
  • A flow file in code may reside at the top level or at any level in a directory structure
  • jar files in lib are expected to be at top level only. Note these files are ignored in Cloud Native installations
  • java and groovy files in lib are expected to be placed in a directory hierarchy according to the Java packages they belong to
  • files in web must follow a directory structure that is consistent with respect to Basepath and RRF directives found in the included flows. Note except for templates, all files placed here will be publicly accessible via HTTP once the archive is deployed
  • The file extension gama is not mandatory, just a mere convention

Metadata#

project.json file is expected to contain metadata about the contents of the archive in JSON format. While these details don't have direct influence in the deployment process, data is saved for reference and can be later retrieved by the API for deployment listing purposes. This is an example:

{
  "projectName": "A name that will be associated to this deployment",
  "author": "A user handle that identifies you",
  "description": "Other relevant data can go here"
}

Sample file#

As an example assume you want to deploy these two flows:

Flow test
    Basepath "hello"

in = { name: "John" }
RRF "templates/index.ftlh" in

Log "Done!"
Finish "john_doe"
Flow com.foods.sweet
    Basepath "recipes/desserts"

...

choice = RRF "selection.ftl"
list = Call com.foods.RecipeUtils#retrieveIngredients choice.meal
...

Here is how the archive might look like:

├── code/
│   └── test.flow
│   └── com.foods.sweet.flow
├── web/
│   ├── hello/
|   |   └── templates/
│   |       └── index.ftlh
│   |           └── js/
│   |               └── font-awesome.js
|   └── recipes/
│       └── desserts/
│           └── selection.ftl
│           └── logo.png
├── lib/
│   └── com/
│       └── foods/
│           └── RecipeUtils.java
└── project.json

API endpoints#

Once a .gama file is built the deployment process follows. Here is a typical workflow:

  1. Send (POST) the archive contents to the deployment endpoint. Normally a 202 response should be obtained meaning a task has been queued for processing
  2. Poll (via GET) the status of the deployment. When the archive has been effectively deployed a status of 200 should be obtained. It may take up to 30 seconds for the process to complete once the archive is sent. This time may extend if there is another deployment in course
  3. Optionally supply configuration parameters for flows if needed. This is done via PUT to the /configs endpoint. The response of the previous step may contain descriptive/sample configurations that can be used as a guide
  4. Test the deployed flows and adjust the archive for any changes required
  5. Go to point 1 if needed
  6. If desired, a request can be sent to undeploy the flows (via DELETE)

The following tables summarize the available endpoints. All URLs are relative to /jans-config-api/api/v1. An OpenAPI document is also available here.

Endpoint -> /agama-deployment/list
Purpose Retrieve a list of deployments in the server. This is not a search, just a paged listing
Method GET
Query params start and count helps paginating results. start is 0-index based. Both params optional
Output Existing deployments (regardless they are thoroughly processed or still being deployed). They are listed and sorted by deployment date
Sample output {"start":...,"totalEntriesCount":...,"entriesCount":...,"entries":[ ... ]}
Status 200 (OK)
Endpoint -> /agama-deployment
Purpose Retrieve details of a single deployment by name
Method GET
Query params name - mandatory
Sample output The structure of a deployment is explained below
Status 200 (deployment task is finished), 204 (task still in course), 404 (project unknown), 400 (a param is missing)
Deployment structure Notes Example
dn Distinguished name jansId=123,ou=deployments,ou=agama,o=jans
id Identifier of deployment (generated automatically) 115276
createdAt Datetime (in UTC) of the instant the deployment task was created (POSTed) 2022-12-07T21:47:42
taskActive Boolean value indicating if the deployment task is being currently processed, ie. the .agama file is being scanned, flows analysed, etc. false
finishedAt Datetime (in UTC) representing the instant when the deployment task was finished, or null if it hasn't ended 2022-12-07T21:48:42
details Extra details, see below
Deployment details structure Notes Example
projectMetadata Includes author, type, description, and project's name - as supplied when the deployment task was created
error A general description of the error (if presented) when processing the task, otherwise null Archive missing web and/or code subdirectories
flowsError A mapping of the errors obtained per flow found in the archive. The keys correspond to qualified names. A null value indicates the flow was successfully added { "co.acme.example": "Syntax error on line 4", "io.jans.test": null }
Endpoint -> /agama-deployment
Purpose Add or replace an ADS project to the server
Method POST
Query params name (the project's name) - mandatory
Body The binary contents of a .gama file; example here. Ensure to use header Content-Type: application/zip
Output Textual explanation, e.g. A deployment task for project XXX has been queued. Use the GET endpoint to poll status
Status 202 (the task was created and scheduled for deployment), 409 (there is a task already for this project and it hasn't finished yet), 400 (a param is missing)
Endpoint -> /agama-deployment/configs
Purpose Retrieve the configurations associated to flows that belong to the project of interest. The project must have been already processed fully
Method GET
Query params name (the project's name) - mandatory
Output A JSON object whose properties are flow names and values correspond to configuration properties defined (JSON objects too)
Status 200 (successful response), 204 (this project is still in course of deployment), 404 (unknown project), 400 (a param is missing)
Endpoint -> /agama-deployment/configs
Purpose Set or replace the configurations associated to flows that belong to the project of interest. The project must have been already processed fully
Method PUT
Query params name (the project's name) - mandatory
Output A JSON object whose properties are flow names and values correspond to a boolean indicating the success of the update for the given flow
Status 200 (successful response), 204 (this project is still in course of deployment), 404 (unknown project), 400 (a param is missing)
Endpoint -> /agama-deployment
Purpose Undeploy an ADS project from the server. Entails removing flows and assets initally supplied
Method DELETE
Query params name (the project's name) - mandatory
Status 204 (scheduled for removal), 409 (the project is being deployed currently), 404 (unknown project), 400 (a param is missing)

Endpoints access#

API operations are protected by Oauth2 scopes this way:

  • GET: https://jans.io/oauth/config/agama.readonly
  • POST: https://jans.io/oauth/config/agama.write
  • DELETE: https://jans.io/oauth/config/agama.delete

Internals of deployment#

This section offers details on how the server deploys a .gama file. In summary five steps take place once the deployment task is picked up:

  1. Input payload validation
  2. Flows transpilation
  3. Transfer of libraries
  4. Transfer of assets and source files
  5. Task finalization

After the initial validation of structure takes place, the code directory is scanned for flow files and every flow is transpiled and added to the database if its transpilation was successful.

Next, jar files found are transferred to the server's custom libs directory - this only applies for VM-based installations.

Then a transfer of templates and assets from web directory followed by copying Groovy/Java sources (from lib) takes place. Finally the deployment task is marked as finalized and a status summary saved to database for later retrieval.

Notes:

  • Developers are required to restart the authentication server and possibly edit the server's XML descriptor for the classes in the jar files to be effectively picked up
  • Steps 3 and 4 are carried out only if all flows passed transpilation successfully
  • In Cloud Native environments only one node takes charge of processing a given deployment thoroughly. Other nodes will automatically sync with regards to the files of step 4.

The API also offers undeployment capabilities. Here is how it works:

  1. Directories holding templates and assets are removed
  2. Source files and jar files are removed, if any
  3. Flows are removed from database

The above applies only for the artifacts originally part of the deployment, of course. Again, nodes in Cloud Native installations will sync accordingly.


Last update: 2023-03-09
Created: 2023-01-20