Add README.md and some minor textual changes

README.md

@@ -0,0 +1,89 @@
+# Simple-Rate-Retriever
+
+Retrieves current rates of ticker symbols. Supports Microsoft Excel's web queries.
+
+## What is Simple-Rate-Retriever?
+
+Simple-Rate-Retriever is a standalone application for the retrieval of current rates of ticker symbols. It does get the
+rates from rate providers by forwarding requests and extracting rates. It does not store rates nor fetch rates other than
+a currently requested rate. Simple-Rate-Retriever supports Microsoft Excel's web queries. This allows it to act as a
+backend for Excel. It basically helps Excel to get current rates from the web.
+
+## Installation
+
+In order to run Simple-Rate-Retriever you need to do the following:
+
+1) Get and install Docker (e.g. "Docker Desktop" from www.docker.com)
+2) Get and install the base-image of [excel-web-query](https://github.com/spartusch/excel-web-query)
+3) Download the source code of simple-rate-retriever and run `./bin/run-container.sh`
+
+## How to use it
+
+There's an OpenAPI specification available for the endpoints provided by Simple-Rate-Retriever. This specification
+is available at `src/main/resources/static/openapi.yml` or during runtime at http://localhost:18091/openapi.yml.
+
+There is also a simple UI at http://localhost:18091/swagger-ui/index.html once Simple-Rate-Retriever is up and running.
+You can query current rates using this UI as well as download web queries  to let Microsoft Excel query and import the rates.
+
+The endpoints require you to provide: 
+- providerId: ID of the provider you'd like to use (e.g. coinmarket or stockexchange)
+- tickerSymbol: Symbol of which to retrieve the current rate of (e.g. BTC or IE00B4L5Y983)
+- currencyCode: Currency of the rate (e.g. USD or EUR)
+- locale: (Optional) The locale used for formatting, must be a language tag according to IETF BCP 47 (e.g. de-DE, defaults to en-US)
+
+### How to use web queries in Microsoft Excel
+
+- Download a web query using the appropriate endpoint (the one ending with `/iqy`)
+- Open Microsoft Excel, go to the "Data" menu, select "Get External Data" and "Run Web Query" / "Run Saved Query", select the web query file and import it
+- Microsoft Excel will now automatically import the current rate whenever it imports external data
+
+## Rate providers
+
+Simple-Rate-Retriever can support an arbitrary number of rate providers. You can query different providers by using their
+providerIds. You can also add new providers very easily.
+
+### Provider: CoinMarketCap
+
+ProviderId:
+`coinmarket`
+
+Example requests:
+- http://localhost:18091/rate/v1/coinmarket/BTC/USD (gets the current Bitcoin rate in USD)
+- http://localhost:18091/rate/v1/coinmarket/ETH/EUR?locale=de-DE (gets the current Ethereum rate in EUR with German formatting)
+
+One of the default providers is [CoinMarketCap](https://coinmarketcap.com/). CoinMarketCap provides rates for many cryptocurrencies.
+You do need to have an API key in order to use this provider though. You can get an API key from https://coinmarketcap.com/api/. There are
+paid plans for the keys but also a "basic plan" which is for free.  Let Simple-Rate-Provider know about your key once you have one.
+Do this by either providing the key in an environment variable  called `CMC_API_KEY` or by creating the file `bin/secrets.vars` with
+the following contents:
+```
+cmc_api_key=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+```
+`xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx` should be replaced with your API key for CoinMarketCap. Please note that the file `bin/secrets.vars`
+is only used when running a command from the `bin` directory, e.g. when running `./bin/run-container.sh`.
+
+### How to add a new provider
+
+Adding new providers is straightforward:
+- Implement the interface `com.github.spartusch.rateretriever.rate.v1.provider.RateProvider` or inherit from `AbstractTimedRateProvider`.
+  You can find the existing implementations at `src/main/kotlin/com/github/spartusch/rateretriever/rate/v1/provider`.
+- Add your new provider to the properties at `src/main/resources/application.yml` under `simple-rate-retriever.providers`and assign it
+  a providerId not yet used.
+- That's it. You can now use your new providerId in requests.
+
+## Monitoring
+
+Simple-Rate-Retriever supports [Prometheus](https://prometheus.io/) as well as [Spring Boot Admin](https://github.com/codecentric/spring-boot-admin)
+for monitoring. 
+
+### Prometheus
+
+An endpoint for Prometheus is provided at http://localhost:18091/actuator/prometheus.
+
+### Spring Boot Admin
+
+You can configure your Spring Boot Admin server in the file `bin/configuration.vars` before running `./bin/run-container.sh` or by setting
+the environment variable SPRING_BOOT_ADMIN_CLIENT_URL.
+By default, Simple-Rate-Retriever will try to find a Spring Boot Admin server at http://admin-server:8080 (when started
+using `./bin/run-container.sh`) or http://localhost:18000 (when started using `./bin/run.sh`).  These locations will work out-of-the-box
+when using the Spring Boot Admin server from https://github.com/spartusch/admin-server.

bin/run-container.sh

@@ -32,7 +32,7 @@ if [[ ! $(docker network ls | grep $project_group) ]];
     echo
 fi
 
-echo "=> Starting new container '$project_name' to be available at port $port ..."
+echo "=> Starting new container '$project_name' listening at port $port ..."
 docker run -p$port:8080 \
   -e CMC_API_KEY=$cmc_api_key \
   -e spring.boot.admin.client.url=$admin_server \

src/main/resources/banner.txt

@@ -8,7 +8,7 @@
                      | |
                      |_|
 
-Copyright (c) 2017-2020 Stefan Partusch
+Copyright (c) 2017-2021 Stefan Partusch
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

src/main/resources/static/openapi.yml

@@ -5,10 +5,10 @@ info:
 externalDocs:
   url: https://github.com/spartusch/simple-rate-retriever
 servers:
-  - url: 'http://localhost:8080'
-    description: Started directly (bin/run.sh, bootRun or IDE)
   - url: 'http://localhost:18091'
     description: Started using docker (bin/run-container.sh)
+  - url: 'http://localhost:8080'
+    description: Started directly (bin/run.sh, bootRun or IDE)
 tags:
   - name: Rate
     description: Provides current rates of ticker symbols
@@ -105,5 +105,4 @@ components:
       pattern: "[A-Z]{3}"
     Locale:
       type: string
-      pattern: "[a-z]{2}-[A-Z]{2}"
       default: "en-US"