Parse an SAP OData V2 XML atom:Feed

This is a work in progress!

The crate is designed to work in conjunction with the source code generated from the crate parse-sap-odata.

Crate parse-sap-odata is invoked by a Rust build script to parse an OData XML metadata file and generates the Rust structs and enums needed to consume the entity set data described by that metadata.

This crate parse-sap-atom-feed then makes use of the structs and enums generated above and allows your business app to consume the XML returned when requesting entity sets from this OData service.

Changes in V0.2

The main change in version 0.2 is to adopt quick-xml's @-prefixed attribute syntax introduced in 0.27 and higher.

Example Usage

You want to develop a Rust application that can consume the entity set data exposed by an SAP OData V2 service.

For the purposes of instruction, let's say you're working with a custom OData service that displays services ordered either by functional location or by date:

Rust Application	zcustom-service-orders
OData Service URL	https://my-sap-server.my-domain.com/sap/opu/odata/sap
OData Service Name	ZCUSTOM_SERVICE_ORDERS_SRV
OData Schema Name	ZCUSTOM_SERVICE_ORDERS
Entity Names	SERVICE_ORDERS_BY_FLOC SERVICE_ORDERS_BY_DATE
Entity Type	ZServiceOrder

The general approach to consuming such a service is as follows:

1. Create a new Rust binary application cargo new zcustom-service-orders
2. cd zcustom-service-orders
3. Edit Cargo.toml to include at least the following dependencies

   [build-dependencies]
   parse-sap-odata = "1.1"
   
   [dependencies]
   chrono = { version = "0.4", features = ["serde"]}
   parse-sap-atom-feed = "0.1"
   rust_decimal = "1.30"
   serde = { version = "1.0", features = ["derive"] }
   uuid = { version = "1.4", features = ["serde"]}

4. mkdir odata
5. Display your service's metadata. E.G. https://my-sap-server.my-domain.com/sap/opu/odata/sap/ZCUSTOM_SERVICE_ORDERS_SRV/$metadata
6. Save the metadata as the file zcustom_service_orders.xml in the odata directory
7. Create a build.rs file in same directory as Cargo.toml and add at least the following:

   use parse_sap_odata::parser::gen_src;
   
   fn main() {
       gen_src("zcustom_service_orders", "ZCUSTOM_SERVICE_ORDERS");
   }

8. In src/main.rs include at least:

   use parse_sap_atom_feed::{
       Feed,
       xml::sanitise_xml,
       str::{self, FromStr},
   };
   
   include!(concat!(env!("OUT_DIR"), "/zcustom_service_orders.rs"));
   
   use zcustom_service_orders::*;
   
   fn main() {
      let raw_xml: String = /* Whatever code is needed to fetch the entity set data as a raw XML string */;
   
      // You might need to sanitise the raw XML string before attempting to parse it
      let clean_xml = sanitise_xml(raw_xml);
   
      let srv_orders_by_floc = Feed::<ZServiceOrder>::from_str(&clean_xml);
   }