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CONTRIBUTING.md

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+
+DEVELOPMENT
+-----------
+
+This reference server is built in GO, serving the protocol described in 
+https://github.com/ga4gh/task-execution-schemas (note, the repo is linked as a
+git submodule, so make sure to use `git clone --recursive`)
+
+The code structure is based on two binary programs
+
+1) tes-server: Provide client API endpoint, web UI, manages work queue.
+The client facing HTTP port (by default 8000) uses a GO web router to serve static HTML
+elements and proxy API requests to a GRPC endpoint, using the GRPC gateway code 
+(https://github.com/grpc-ecosystem/grpc-gateway)
+The GRPC endpoint (usually bound to port 9090) is based on the auto-generated GO 
+protoc GRPC server. It is bound to two services: the GA4GH Task Execution Service 
+and a internal service protocol that is used by the workers to access the work queue.
+
+2) tes-worker: A client that uses the internal service protocol to contact task 
+scheduler (on port 9090) and requests jobs. It is then responsible for obtaining the 
+required input files (thus it much have code and credentials to access object store),
+run the docker container with the provided arguments, and then copy the result files 
+out to the object store.
+
+Code Structure
+--------------
+
+Main function of taskserver program (client interface and scheduler)
+src/tes-server/
+
+Main function of worker program
+src/tes-worker/
+
+Code related to the worker, include file mapper, local and swift file system clients, docker interfaces and worker thread manager
+src/tes/worker/
+
+The compiled copy of the Task Execution Schema protobuf
+src/tes/ga4gh
+
+BoltDB based implementation of the TES api as well as the scheduler API.
+src/tes/server
+
+The compiled copy of the scheduler API protobuf
+src/tes/server/proto/
+
+Python driven unit/conformance tests
+tests
+
+HTML and angular app for web view
+share
+
+
+Rebuilding Proto code
+---------------------
+First install protoc extentions (GRPC and GRPC gateway builder programs)
+```
+make depends
+```
+Rebuild auto-generated code
+```
+make proto_build
+```
+
+
+Running Tests
+-------------
+The integration testing is done using Python scripts to drive client API requests.
+To run tests:
+```
+nosetests tests
+```
+
+